The burden of disease and injury in Australia - 2003

The Australian Institute of Health and Welfare is Australia’s national health and welfare statistics and information agency. The Institute’s mission is better health and wellbeing for Australians through better health and welfare statistics and information.

Please note that as with all statistical reports there is the potential for minor revisions of data in this report over its life. Please refer to the online version at <www.aihw.gov.au/bod>.

1School of Population Health, University of Queensland, Brisbane

2Australian Institute of Health and Welfare, Canberra

AIHW cat. no. PHE 82

Stephen Begg1, Theo Vos1, Bridget Barker1,

Chris Stevenson2, Lucy Stanley1 and Alan D Lopez1

May 2007

© Australian Institute of Health and Welfare 2007

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ISBN 978 1 74024 648 4

Suggested citation

Begg S, Vos T, Barker B, Stevenson C, Stanley L, Lopez AD, 2007. The burden of disease and injury

in Australia 2003. PHE 82. Canberra: AIHW.

Australian Institute of Health and Welfare

Board Chair

Hon. Peter Collins, AM, QC

Director

Penny Allbon

Any enquiries about or comments on this publication should be directed to:

John Goss

Australian Institute of Health and Welfare

GPO Box 570

Canberra ACT 2601

Phone: (02) 6244 1151

Email: burdenofdisease@aihw.gov.au

Published by the Australian Institute of Health and Welfare

PPrriinntteedd bbyy Canprint Communications

v

Foreword

Exactly a decade ago, the results of the first Global Burden of Disease (GBD) Study were

published by Harvard University on behalf of the World Health Organization and the World

Bank. These organisations and several countries then became interested in applying the GBD

approach to better inform health policy, leading to a series of country studies on all

continents. Probably the most technically competent and comprehensive of these were the

Australian studies, led by Colin Mathers, for Australia as a whole, and Theo Vos for the state

of Victoria. These analyses were based around 1996 data and have been widely used to

inform priority setting and health policy debates in Australia.

As a result of these initial studies, governments across Australia have become interested in

using the burden of disease framework to help quantify health needs. There have also been

advances in methods over the past ten years and greater interest among the health policy

community in information about the burden of disease in population subgroups. This has all

stimulated the need for a revised Australian burden of disease and injury study to update

and extend the initial efforts.

This report responds to that need. Some of the world’s leading researchers in burden of

disease studies, with extensive experience in national applications of the methods, have

joined the University of Queensland to create the great focus of expertise reflected in this

study. Building on the analytical framework of previous studies, the report includes a

number of important extensions of the framework that are highly relevant for policy. They

include disease projections, small area analyses and state-level burden of disease results.

Also, better methods around comorbidity and risk factor assessment have much improved

the scientific basis of the findings reported here.

This comprehensive study will undoubtedly meet the need for detailed information about

the burden of disease and injury in Australia and its jurisdictions, about the principal causes

of that burden, and how it is changing. But it alone is not enough. With rising pressure on

health budgets, governments will increasingly rely not only on information about the burden

of disease and injury, but also on cost-effective ways of reducing that burden. This study is a

critical and fundamental step in that policy process and we expect it to be used widely to

help improve the health of all Australians.

Alan Lopez Penny Allbon

Professor of Medical Statistics and Director

Population Health, Australian Institute of Health and Welfare

The University of Queensland

vii

Contents

Foreword .............................................................................................................................................. v

Executive summary ..............................................................................................................................1

Introduction ...................................................................................................................................1

Key findings ...................................................................................................................................2

Total burden of disease and injury.......................................................................................2

Health risks ..............................................................................................................................5

Differentials in burden across Australia..............................................................................6

Trends—past, present and future.........................................................................................7

Key implications.....................................................................................................................8

1 Introduction...................................................................................................................................9

1.1 Purpose....................................................................................................................................9

1.2 Background.............................................................................................................................9

1.3 Summary measures of population health .........................................................................10

1.4 Disability-Adjusted Life Years ............................................................................................11

1.5 Burden of disease analysis in Australia.............................................................................12

1.6 Burden in Aboriginal and Torres Strait Islander peoples ...............................................13

1.7 Structure of report.................................................................................................................13

2 Methodological developments .................................................................................................15

2.1 Social value choices...............................................................................................................15

2.2 Causal attribution .................................................................................................................17

Categorising deaths ..............................................................................................................18

Redistributing non-specific causes of death......................................................................19

Alternative categories...........................................................................................................25

2.3 Comorbidity and health.......................................................................................................25

2.4 Risks to health........................................................................................................................27

Explicit ‘counterfactuals’......................................................................................................28

Joint risk attribution..............................................................................................................29

2.5 Past, present and future burden .........................................................................................30

Mortality trends and projections ........................................................................................32

Incidence and case-fatality...................................................................................................32

Non-fatal conditions .............................................................................................................33

2.6 Differentials in burden ..........................................................................................................34

Categorising geographic areas ............................................................................................34

Estimating burden for subpopulations..............................................................................35

Subpopulation comparisons in this report........................................................................36

viii

3 Burden of disease and injury in Australia .............................................................................37

3.1 Disability-adjusted life years...............................................................................................37

3.2 Years of life lost .....................................................................................................................40

3.3 Years lost due to disability...................................................................................................43

Incident YLD..........................................................................................................................43

Prevalent YLD .......................................................................................................................46

3.4 Age and sex patterns ............................................................................................................47

Children aged 0–14 years.....................................................................................................47

Older children and adults aged 15–44 years.....................................................................49

Adults aged 45–64 years ......................................................................................................50

Adults aged 65–74 years ......................................................................................................51

Older people aged 75 years and over.................................................................................53

3.5 Specific disease and injury categories ................................................................................54

Cancers ..................................................................................................................................55

Cardiovascular disease.........................................................................................................58

Mental disorders ...................................................................................................................59

Neurological and sense disorders.......................................................................................62

Chronic respiratory diseases ...............................................................................................64

Injuries ...................................................................................................................................65

Diabetes .................................................................................................................................67

Musculoskeletal diseases .....................................................................................................69

Alternative categories for selected conditions ..................................................................71

4 Risks to health in Australia.......................................................................................................72

4.1 Overview...............................................................................................................................72

4.2 Combined effect of 14 selected risks to health..................................................................73

4.3 Individual contribution of 14 selected risks to health......................................................76

Tobacco..................................................................................................................................76

High blood pressure .............................................................................................................77

High body mass ....................................................................................................................79

Physical inactivity .................................................................................................................81

High blood cholesterol .........................................................................................................83

Alcohol...................................................................................................................................84

Low fruit and vegetable consumption...............................................................................87

Illicit drugs .............................................................................................................................88

Occupational exposures and hazards ................................................................................90

Intimate partner violence.....................................................................................................92

Child sexual abuse ................................................................................................................93

Urban air pollution ...............................................................................................................95

ix

Unsafe sex ..............................................................................................................................98

Osteoporosis ..........................................................................................................................99

5 Differentials in burden of disease and injury across Australia .......................................101

5.1 Overview.............................................................................................................................101

5.2 Health-adjusted life expectancy........................................................................................102

5.3 State and territory differentials .........................................................................................105

5.4 Differentials by socioeconomic status..............................................................................108

5.5 Differentials by remoteness ...............................................................................................111

6 Past, present and future burden of disease and injury in Australia ...............................114

6.1 Overview..............................................................................................................................114

6.2 Health-adjusted life expectancy.........................................................................................115

6.3 Burden .................................................................................................................................122

7 Discussion and conclusions ....................................................................................................129

7.1 Potential applications .........................................................................................................129

7.2 Policy implications..............................................................................................................130

7.3 Precision of estimates .........................................................................................................131

Fatal burden.........................................................................................................................131

Non-fatal burden.................................................................................................................131

7.4 Access to data ......................................................................................................................134

7.5 Future directions .................................................................................................................134

Appendix 1: Methods for estimating disability burden ...........................................................137

1A Infectious and parasitic diseases........................................................................................138

Tuberculosis........................................................................................................................138

Sexually transmitted diseases (excluding HIV/AIDS)..................................................138

HIV/AIDS...........................................................................................................................138

Diarrhoeal diseases .............................................................................................................139

Childhood immunisable diseases.....................................................................................139

Pertussis...............................................................................................................................139

Tetanus ................................................................................................................................139

Measles ................................................................................................................................140

Rubella.................................................................................................................................140

Haemophilus influenzae type b.............................................................................................140

Meningitis ............................................................................................................................140

Septicaemia ..........................................................................................................................141

Arbovirus infections ...........................................................................................................141

Hepatitis ...............................................................................................................................141

Malaria.................................................................................................................................143

Trachoma.............................................................................................................................143

ix

Unsafe sex ..............................................................................................................................98

Osteoporosis ..........................................................................................................................99

5 Differentials in burden of disease and injury across Australia .......................................101

5.1 Overview.............................................................................................................................101

5.2 Health-adjusted life expectancy........................................................................................102

5.3 State and territory differentials .........................................................................................105

5.4 Differentials by socioeconomic status..............................................................................108

5.5 Differentials by remoteness ...............................................................................................111

6 Past, present and future burden of disease and injury in Australia ...............................114

6.1 Overview..............................................................................................................................114

6.2 Health-adjusted life expectancy.........................................................................................115

6.3 Burden .................................................................................................................................122

7 Discussion and conclusions ....................................................................................................129

7.1 Potential applications .........................................................................................................129

7.2 Policy implications..............................................................................................................130

7.3 Precision of estimates .........................................................................................................131

Fatal burden.........................................................................................................................131

Non-fatal burden.................................................................................................................131

7.4 Access to data ......................................................................................................................134

7.5 Future directions .................................................................................................................134

Appendix 1: Methods for estimating disability burden ...........................................................137

1A Infectious and parasitic diseases........................................................................................138

Tuberculosis........................................................................................................................138

Sexually transmitted diseases (excluding HIV/AIDS)..................................................138

HIV/AIDS...........................................................................................................................138

Diarrhoeal diseases .............................................................................................................139

Childhood immunisable diseases.....................................................................................139

Pertussis...............................................................................................................................139

Tetanus ................................................................................................................................139

Measles ................................................................................................................................140

Rubella.................................................................................................................................140

Haemophilus influenzae type b.............................................................................................140

Meningitis ............................................................................................................................140

Septicaemia ..........................................................................................................................141

Arbovirus infections ...........................................................................................................141

Hepatitis ...............................................................................................................................141

Malaria.................................................................................................................................143

Trachoma.............................................................................................................................143

x

1B Acute respiratory infections ................................................................................................144

Lower respiratory tract infections ....................................................................................144

Upper respiratory tract infections ....................................................................................144

Otitis media..........................................................................................................................145

1C Maternal conditions .............................................................................................................145

1D Neonatal causes....................................................................................................................146

Birth trauma and asphyxia ................................................................................................146

Low birth weight.................................................................................................................146

Neonatal infections .............................................................................................................147

Other conditions arising in the perinatal period ............................................................147

1E Nutritional deficiencies........................................................................................................147

Iron deficiency anaemia .....................................................................................................147

2F Malignant neoplasms ...........................................................................................................147

Disease incidence data........................................................................................................148

Cure rate and mean survival time ....................................................................................148

Long-term sequelae of cancer............................................................................................149

2G Other neoplasms ..................................................................................................................150

2H Diabetes ................................................................................................................................150

Diabetes cases ......................................................................................................................150

Retinopathy.........................................................................................................................151

Cataract and glaucoma.......................................................................................................151

Renal failure........................................................................................................................152

Neuropathy.........................................................................................................................152

Peripheral vascular disease ...............................................................................................152

Amputation and diabetic foot ...........................................................................................152

Ischaemic heart disease and stroke ..................................................................................153

2I Endocrine and metabolic disorders.....................................................................................153

Haemolytic anaemia...........................................................................................................153

Other non-deficiency anaemia ..........................................................................................153

Cystic fibrosis ......................................................................................................................153

Haemophilia ........................................................................................................................154

2J Mental disorders ....................................................................................................................154

Depression & anxiety, substance abuse (excluding heroin and stimulant

dependence), borderline personality disorder and bipolar disorder ..........................154

Heroin dependence and harmful use...............................................................................156

Stimulant dependence........................................................................................................156

Psychotic disorders .............................................................................................................157

Eating disorders ..................................................................................................................158

Childhood disorders...........................................................................................................158

xi

2K Nervous system and sense organ disorders.....................................................................159

Dementia ..............................................................................................................................159

Epilepsy ...............................................................................................................................159

Parkinson’s disease.............................................................................................................159

Motor neurone disease .......................................................................................................160

Multiple sclerosis ................................................................................................................160

Huntington’s chorea ...........................................................................................................161

Muscular dystrophy ...........................................................................................................161

Vision loss ............................................................................................................................161

Hearing loss .........................................................................................................................162

Intellectual disability ..........................................................................................................162

Migraine ...............................................................................................................................163

2L Cardiovascular disease ........................................................................................................163

Ischaemic heart disease ......................................................................................................163

Heart diseases resulting in heart failure ..........................................................................164

Stroke ...................................................................................................................................165

Other cardiovascular disease ............................................................................................166

2M Chronic respiratory diseases..............................................................................................167

Chronic obstructive pulmonary disease ..........................................................................167

Asthma.................................................................................................................................167

2N Diseases of the digestive system........................................................................................168

Peptic ulcer disease.............................................................................................................168

Cirrhosis of the liver ...........................................................................................................168

Inflammatory bowel disease .............................................................................................168

Other diseases of the digestive system............................................................................169

2O Genitourinary diseases........................................................................................................169

Nephritis & nephrosis ........................................................................................................169

Benign prostatic hypertrophy ...........................................................................................169

Urinary incontinence ..........................................................................................................170

Infertility..............................................................................................................................170

Other genitourinary diseases ............................................................................................171

2P Skin diseases.........................................................................................................................171

Eczema, acne and psoriasis................................................................................................171

Other skin diseases .............................................................................................................171

2Q Musculoskeletal diseases ....................................................................................................172

Rheumatoid arthritis ..........................................................................................................172

Osteoarthritis .......................................................................................................................172

Back pain ..............................................................................................................................173

xii

Slipped disc..........................................................................................................................173

Occupational overuse syndrome ......................................................................................173

Gout......................................................................................................................................174

Other musculoskeletal disorders ......................................................................................174

2R Congenital anomalies...........................................................................................................175

Congenital heart disease ....................................................................................................175

Digestive system malformations.......................................................................................175

Renal agenesis .....................................................................................................................175

Other urogenital tract malformations ..............................................................................175

Other congenital anomalies...............................................................................................176

2S Oral conditions ......................................................................................................................176

Caries ...................................................................................................................................176

Edentulism..........................................................................................................................177

Periodontal disease .............................................................................................................178

Pulpitis.................................................................................................................................178

2Z Chronic fatigue syndrome...................................................................................................178

3 Injuries .....................................................................................................................................179

Appendix 2: Methods for attributing risk ...................................................................................180

Estimating population attributable fractions .........................................................................180

Choice of theoretical minimum................................................................................................181

Estimating attributable burden ................................................................................................181

Tobacco................................................................................................................................182

High blood pressure ...........................................................................................................182

High body mass ..................................................................................................................183

Physical inactivity ...............................................................................................................183

High blood cholesterol .......................................................................................................184

Alcohol.................................................................................................................................184

Low fruit and vegetable consumption.............................................................................185

Illicit drugs ...........................................................................................................................185

Occupational exposures and hazards ..............................................................................186

Child sexual abuse and intimate partner violence .........................................................187

Urban air pollution .............................................................................................................188

Unsafe sex ............................................................................................................................191

Osteoporosis ........................................................................................................................191

Annex tables .....................................................................................................................................201

Acknowledgments...........................................................................................................................285

Advisory committee ..................................................................................................................285

Expert advisors ...........................................................................................................................286

xiii

Abbreviations and symbols............................................................................................................288

References.........................................................................................................................................291

List of tables .....................................................................................................................................315

List of figures ...................................................................................................................................319

1

Executive summary

Introduction

This report is the first complete assessment of the health of Australians to be released in the new millennium. 

The findings in this report -

(i)        identify the extent and distribution of health problems in Australia, and

(ii)       quantify the contribution of key health risk factors to these problems

Levels of death and disability from a comprehensive set of diseases, injuries and risks to health are combined to measure the total health ‘burden’.

This report is the second of this type in Australia, the first having been released in 1999.  It expands the scope of that previous report and also presents for the first time:

•         the differentials of health burden across areas and population groups in Australia

•         the joint contribution of key health risks—including combined lifestyle, physiological, social and environmental factors—on health

•         an analysis of past trends of health burden and the likely health of Australians in 20 years from now should those trends continue.

The findings of this report describe the health loss due to disease and injury that is not ameliorated by current treatment, rehabilitative and preventive efforts of the health system and society generally. Thus they represent the ‘unmet’ challenges of the health system and are best interpreted as opportunities for health gain.

By providing a comprehensive database of all relevant epidemiological and burden parameters through time, the report will benefit health policy development and research in relation to -

  1. preventive and curative health interventions,

  2. health care expenditure projections, and

  3. further assessments of health burden in the period before the next major update.

The study upon which the report is based was funded by the Australian Government Department of Health and Ageing. A report specifically examining the burden of disease and injury in Aboriginal and Torres Strait Islander people will be published separately.

2

Key findings

Total burden of disease and injury

The key measure used in this report to measure the total burden of disease and injury is the ‘disability-adjusted life year’ (DALY). It describes the amount of time lost due to both fatal and non-fatal events, that is, years of life lost due to premature death coupled with years of ‘healthy’ life lost due to disability.

Cancer

Cardiovascular

Neuro- Mental

logical

Chronic

respiratory

Injuries

Diabetes

Musculoskeletal

Other

19%

18%

12% 13%

7%

7%

5%

4%

14%

Total

Injuries

Diabetes

Cardiovascular

Chronic respiratory

Cancer

Mental

Neurological

Musculoskeletal

52%

70%

54%

53%

53%

53%

47%

47%

42%

48%

30%

46%

47%

47%

47%

53%

53%

58%

Males Females

Total

Cancer

Cardiovascular

Injuries

Chronic respiratory

Diabetes

Neurological

Musculoskeletal

Mental

49%

82%

78%

76%

38%

22%

17%

7%

7%

51%

18%

22%

24%

62%

78%

83%

93%

93%

Fatal Non-fatal

Burden (DALYs) by broad cause group expressed as: (a) proportions of total, (b) proportions

by sex, and (c) proportions due to fatal and non-fatal outcomes, Australia, 2003

• In 2003, more than 2.63 million years of ‘healthy’ life (that is, DALYs) were lost due to the burden of disease and injury in Australia.

• Cancers (19%) and cardiovascular disease (18%) were the leading causes of the burden of disease and injury in Australia in 2003, accounting for 37% of the total burden.

Four-fifths of that burden was from premature deaths. For the first time, cancer has overtaken cardiovascular disease as the greatest cause of burden in Australia.

• Lung, colorectal and breast cancer were the leading specific causes of the burden of cancer.

• Ischaemic heart disease, stroke, and peripheral vascular disease were the leading specific causes of cardiovascular burden.

• Mental disorders and neurological & sense disorders were the next largest contributors, together accounting for a further 25% of the total health burden. Less than one-fifth of that burden was from premature deaths.

• Anxiety & depression, alcohol abuse, and personality disorders dominated the burden of mental disorders.

• Dementia, adult-onset hearing loss, and vision loss were the leading causes of burden due to neurological & sense disorders.

• Anxiety & depression also carries a risk of ischaemic heart disease and suicide, increasing the total burden due to the combined category of anxiety & depression from 7.3% to 8.2%.

• Diabetes also carries a risk of ischaemic heart disease and stroke, increasing the total burden of diabetes from 5.5% to 8.3%, and making it the fourth largest contributor to overall burden after cancer, CVD and mental disorders.

• The eight national health priority conditions—asthma, cancer, cardiovascular disease, diabetes mellitus, injuries, mental health, arthritis and musculoskeletal conditions, and dementia—accounted for 72.8% of the total burden in 2003.

• Distribution of the burden between the sexes was roughly equal except for injuries (70% of the burden in males) and musculoskeletal (58% of the burden in females).

• The five leading specific causes of burden in men were ischaemic heart disease (11.1%), Type 2 diabetes (5.2%), anxiety & depression (4.8%), lung cancer (4.0%) and stroke (3.9%).

• The five leading specific causes of burden in women were anxiety & depression (10.0%), ischaemic heart disease (8.9%), stroke (5.1%), Type 2 diabetes (4.9%) and dementia (4.8%).

• Disability from all diseases and injuries resulted in a loss of 1.5% of healthy time lived by children, increasing with age to 14.7% in those aged 65 to 69 years, to 41.5% in the very aged.

Fatal burden

• ‘Life expectancy’ estimates the average years of life that a person can expect to live given current risks of mortality. In 2003 in Australia, life expectancy at birth was 80.7 years (78.3 years for males and 83.2 years for females).

• Fatal burden—measured in years of life lost (YLL)—accounted for 49% of the total burden of disease and injury in Australia in 2003.

• Cancers (32.0%), cardiovascular disease (29.0%) and injuries (11.0%) were responsible for almost three-quarters of the fatal burden.

• Males experienced 55% of total fatal burden. The five leading specific causes of mortality burden among men were ischaemic heart disease (18.2%), lung cancer (7.3%), suicide & self-inflicted injury (5.4%), stroke (5.1%) and colorectal cancer (3.9%).

• Females experienced 45% of total fatal burden. The five leading specific causes of mortality burden among women were ischaemic heart disease (15.7%), stroke (8.5%), breast cancer (7.0%), lung cancer (5.5%) and colorectal cancer (4.2%).

Non-fatal burden

• ‘Health adjusted life expectancy’ (HALE) estimates the average years of equivalent ‘healthy life’ that a person can expect to live. In 2003 in Australia, the average HALE was 72.9 years (70.6 years for males and 75.2 years for females), with 9.7% of life expectancy at birth lost due to disability.

• Non-fatal burden—measured in years of ‘healthy’ life lost due to disability (YLD)—accounted for 51% of the total burden of disease and injury in Australia in 2003.

4

• Mental disorders (24%) and neurological & sense disorders (19%) contributed most to non-fatal burden.

• The five leading specific causes of non-fatal burden among men were anxiety & depression (10.0%), Type 2 diabetes (8.5%), adult-onset hearing loss (6.5%), asthma (4.2%) and dementia (3.9%).

• The five leading specific causes of non-fatal burden among women were anxiety & depression (18.1%), Type 2 diabetes (7.2%), dementia (6.4%), asthma (4.5%) and ischaemic heart disease (3.3%).

Age patterns and total burden

Distribution of population and burden (DALYs) by five broad age groups, Australia, 2003

Age group Population(a)

Per cent of total DALYs

Per cent of total

0–14 years 3,979,410 20.0 221,536 8.4

15–44 years 8,622,610 43.4 633,260 24.1

45–64 years 4,733,808 23.8 681,566 25.9

65–74 years 1,349,949 6.8 428,904 16.3

75 years and over 1,195,692 6.0 667,504 25.4

Total 19,881,469 100.0 2,632,770 100.0

(a) Estimated resident population figures as at 30 June 2003 (ABS cat. no. 3201.0).

• Adults aged 45 to 64 years comprised 23.8% of the population in 2003 and experienced the largest proportion (25.9%) of disease and injury burden across key age groups.

Cancer (28%), cardiovascular disease (16%) and neurological disorders (10%) accounted for more than half the total burden in this age group. Almost half of the burden was due to mortality.

• Adults aged over 75 years comprised 6.0% of the population but experienced the second highest proportion of burden (25.4%). Cardiovascular disease (34%) and cancer (19%) accounted for more than half of the burden. Overall, 68% of the burden was due to mortality.

• Adults aged 15 to 44 years represented the largest age group (43.4% of the population) and experienced 24.1% of the burden. Mental disorders (36%) and injuries (17%) accounted for more than half of the total burden in this age group. Mortality contributed 29% to the burden in this age group.

• Children aged 0-14 years comprised 20.0% of the population and experienced 8.4% of the total burden of disease and injury (DALY) in Australia in 2003. Twenty-three per cent of this burden was due to mental disorders, 18% to chronic respiratory disorders, and 16% to neonatal conditions. About one-quarter of the burden was due to mortality.

• Mental disorders (24%) and neurological & sense disorders (19%) contributed most to non-fatal burden.

• The five leading specific causes of non-fatal burden among men were anxiety & depression (10.0%), Type 2 diabetes (8.5%), adult-onset hearing loss (6.5%), asthma (4.2%) and dementia (3.9%).

• The five leading specific causes of non-fatal burden among women were anxiety & depression (18.1%), Type 2 diabetes (7.2%), dementia (6.4%), asthma (4.5%) and ischaemic heart disease (3.3%).

Age patterns and total burden

Distribution of population and burden (DALYs) by five broad age groups, Australia, 2003

Age group Population(a)

Per cent

of total DALYs

Per cent

of total

0–14 years 3,979,410 20.0 221,536 8.4

15–44 years 8,622,610 43.4 633,260 24.1

45–64 years 4,733,808 23.8 681,566 25.9

65–74 years 1,349,949 6.8 428,904 16.3

75 years and over 1,195,692 6.0 667,504 25.4

Total 19,881,469 100.0 2,632,770 100.0

(a) Estimated resident population figures as at 30 June 2003 (ABS cat. no. 3201.0).

• Adults aged 45 to 64 years comprised 23.8% of the population in 2003 and experienced the largest proportion (25.9%) of disease and injury burden across key age groups.

Cancer (28%), cardiovascular disease (16%) and neurological disorders (10%) accounted for more than half the total burden in this age group. Almost half of the burden was due to mortality.

• Adults aged over 75 years comprised 6.0% of the population but experienced the second highest proportion of burden (25.4%). Cardiovascular disease (34%) and cancer (19%)

accounted for more than half of the burden. Overall, 68% of the burden was due to mortality.

• Adults aged 15 to 44 years represented the largest age group (43.4% of the population) and experienced 24.1% of the burden. Mental disorders (36%) and injuries (17%) accounted for more than half of the total burden in this age group. Mortality contributed 29% to the burden in this age group.

• Children aged 0-14 years comprised 20.0% of the population and experienced 8.4% of the total burden of disease and injury (DALY) in Australia in 2003. Twenty-three per cent of  his burden was due to mental disorders, 18% to chronic respiratory disorders, and 16% to neonatal conditions. About one-quarter of the burden was due to mortality.

5

Health risks

Individual and joint burden (DALYs) attributable to 14 selected risk factors by broad cause group,

Australia, 2003

Broad cause group

Cancer CVD Mental

Neurological

Injury Diabetes Other

All

causes

Total burden (‘000) 499.4 473.8 350.5 312.8 185.1 143.8 667.4 2,632.8

Attributable burden (%)(a)

Tobacco 20.1 9.7 — –0.6 0.5 — 8.9 7.8

High blood pressure — 42.1 — — — — — 7.6

High body mass 3.9 19.5 — — — 54.7 1.1 7.5

Physical inactivity 5.6 23.7 — — — 23.7 >–0.1 6.6

High blood cholesterol — 34.5 — — — — — 6.2

Alcohol

Harmful effects 3.1 0.9 9.7 — 18.1 — <0.1 3.3

Beneficial effects — –5.6 — — — — >–0.1 –1.0

Net effects 3.1 –4.7 9.7 — 18.1 — <0.1 2.3

Low fruit & vegetable

consumption 2.0 9.6 — — — — >–0.1 2.1

Illicit drugs — <0.1 8.0 — 3.6 — 2.5 2.0

Occupational exposures &

hazards 3.1 0.4 — 0.8 4.7 — 3.4 2.0

Intimate partner violence 0.5 0.3 5.5 0.1 2.5 — 0.2 1.1

Child sexual abuse <0.1 <0.1 5.8 — 1.4 — <0.1 0.9

Urban air pollution 0.8 2.7 — — — — 0.4 0.7

Unsafe sex 1.0 — — — — — 1.4 0.6

Osteoporosis — — — — 2.4 — — 0.2

Joint effect(b) 32.9 69.3 26.9 0.2 31.7 60.1 17.2 32.2

(a) Attributable burden within each column is expressed as a percentage of total burden for that column.

(b) Figures for joint effects are not column totals. See Section 4.1 for further details.

Findings on the amount of burden in 2003 that was attributable to current and past exposures to risks to health considered the following:

• Lifestyle behaviours (tobacco smoking, physical inactivity, alcohol consumption, low fruit and vegetable consumption, use of illicit drugs, and unsafe sex)

• Physiological states (high body mass, high blood pressure, high cholesterol, and osteoporosis)

• Social and environmental factors (occupational exposures and hazards, intimate partner violence, child sexual abuse, and urban air pollution).

The 14 risks together explained 32.2% of the total burden of disease and injury in Australia in 2003.

• Tobacco was responsible for the greatest disease burden in Australia (7.8% of total burden), followed by high blood pressure (7.6%), high body mass (7.5%), physical +inactivity (6.6%), and high blood cholesterol (6.2%).

6

• The five leading risks in males in 2003 were tobacco (9.6%), high blood pressure (7.8%), high body mass (7.7%), high blood cholesterol (6.6%) and physical inactivity (6.4%).

• Among women the leading risks were high blood pressure (7.3%), high body mass (7.3%), physical inactivity (6.8%), high blood cholesterol (5.8%) and tobacco (5.8%).

This report sets out for the first time the combined or ‘joint’ effect of these risks on health, accounting for the fact that many risks share complex causal pathways. It is difficult to quantify the exact contribution of each risk to the combined totals, but the proportion of totalburden that is ‘explained’ by multiple risks within each disease and injury category can be reported with sufficient accuracy.

• Ten risks were associated with cancer and together explained 32.9% of the cancer burden. The majority was explained by tobacco but also included the effect of physical inactivity, high body mass, and alcohol consumption.

• Twelve risks were associated with cardiovascular disease and together explained 69.3% of the disease burden; for ischaemic heart disease this figure was 85.2%. High blood pressure and high blood cholesterol were the largest contributors.

• Three risks were associated with neurological and sensory disorders and together explained 0.2% of the burden from these disorders. This reflects a lack of knowledge about causation in this group.

• Two risks were associated with Type 2 diabetes and together explained 60.1% of the total burden. High body mass was by far the largest contributor (54.7%) followed by physical inactivity (23.7%).

• The burden associated with harmful alcohol consumption (3.2%) was partially offset by the cardiovascular disease prevented by safe levels of alcohol consumption (–0.9%). This protective factor only becomes apparent after 45 years of age, whereas the harmful effects of alcohol are apparent at all ages.

Differentials in burden across Australia

• This report shows for the first time that there are differentials across Australia in the proportion of life expectancy lost due to disability. There was a strong socioeconomic gradient in this measure, and differentials with respect to remoteness were also apparent but not as large.

• Health-adjusted life expectancy (HALE) in 2003 in Australia was 72.9 years (70.6 for males and 75.2 for females), with an average 9.7% of life expectancy at birth lost due to disability.

• Across states and territories, the proportion of life expectancy lost due to disability ranged from 7.7% in the ACT to 10.6% in South Australia. The NT had almost twice the rate of total burden of the ACT due to a higher rate of burden for most causes, but particularly cardiovascular disease, diabetes, and injury.

• Across socioeconomic quintiles, the proportion of life expectancy lost due to disability ranged from 8.7% in the highest quintile to 10.6% in the lowest. The 31.7% greater burden for the most disadvantaged population compared to the highest was due to higher rates of burden for most causes, but particularly mental disorders and cardiovascular disease.

7

Health-adjusted life expectancy (HALE) and life expectancy at birth lost due to disability by area and sex, Australia, 2003

Health-adjusted life expectancy (HALE) (years)

At birth At age 60

Life expectancy at birth lost due to disability (%)

Area Males Females Persons Males Females Persons Males Females Persons

Jurisdiction

NSW 70.5 75.3 72.9 17.1 20.6 18.9 9.8 9.5 9.6

Vic 71.1 75.4 73.2 17.5 20.8 19.2 9.6 9.4 9.5

Qld 70.5 75.3 72.8 17.0 20.4 18.7 10.1 9.7 9.9

WA 71.5 75.6 73.5 17.5 20.6 19.1 9.6 9.6 9.6

SA 69.3 74.2 71.7 16.4 20.0 18.3 10.8 10.5 10.6

Tas 68.8 73.7 71.3 16.3 19.7 18.1 10.2 9.8 10.0

NT 65.8 70.2 67.7 12.6 15.1 13.6 10.0 10.6 10.3

ACT 73.9 77.8 75.9 18.9 21.9 20.5 7.8 7.5 7.7

Socioeconomic quintile

Low 68.7 73.8 71.2 16.1 19.7 17.9 10.7 10.4 10.6

Moderately

low 69.5 74.6 72.0 16.4 20.1 18.2 10.2 9.9 10.1

Average 69.9 74.6 72.2 16.6 20.1 18.4 10.0 9.8 9.9

Moderately

high 71.4 75.9 73.6 17.6 20.8 19.3 9.7 9.1 9.4

High 73.8 77.2 75.5 19.2 21.9 20.6 8.7 8.7 8.7

Remoteness

Major cities 71.3 75.6 73.5 17.5 20.8 19.2 9.6 9.4 9.5

Regional 69.6 74.5 72.0 16.5 20.1 18.3 10.3 9.8 10.1

Remote 67.3 72.3 69.5 15.4 18.5 16.8 10.8 11.3 11.0

Australia 70.6 75.2 72.9 17.1 20.5 18.9 9.8 9.6 9.7

• Based on remoteness, the proportion of life expectancy lost due to disability ranged from

9.5% in major cities to 11.0% in remote areas. The 26.5% greater burden for remote areas

compared to major cities reflected a higher burden per person from most causes but

particularly injuries.

Trends—past, present and future

This report presents an analysis of health trends over a 30-year period, based on the past decade and projected trends of health burden if these trends continued over the next 20 years.

• The average years of ‘healthy life’ a person can expect to live (HALE) will grow at a slower rate than life expectancy over the next 20 years. If past trends in morbidity and mortality continue, HALE will increase 0.22% annually and life expectancy 0.24% annually. This is partly because declines in mortality will be accompanied by a somewhat smaller decline in time that is lost to disability.

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• The rate of disability will actually decline in most age groups, except for those 80 years and over, where it is expected to increase and thereby offset some of the gains for younger age groups. The growing rate of disability in the oldest age group mostly comes from expected increases in diabetes and neurological conditions.

Key implications

Key implications of the report’s findings include:

• Ageing of Australia’s population will result in increasing numbers of people with disability from diseases more common in older ages such as dementia, Parkinson’s disease, hearing and vision loss, and osteoarthritis. This will increase demand for services in the home, community care, residential aged care and palliative care sectors.

• Cardiovascular disease has been overtaken by cancer as the major cause of burden in Australia. This has been largely as a result of programs which have reduced smoking and facilitated the use of therapies to lower cholesterol and blood pressure levels, as well as better treatment of existing cardiovascular disease.  It is likely that additional gains could be made through increasing the coverage of these interventions.

• Cancer is expected to retain its share of total health burden. Age-standardised rates of death and disability are expected to fall, but cancer will remain the largest contributor to the health burden in 20 years time.

• There is likely to be strong growth in the burden of diabetes over the next 20 years, mostly as a direct consequence of increasing levels of obesity. The disability consequences of increasing obesity will be magnified as fatality rates for people with diabetes continue to decline. This increased survival will mean an increase in the risk of people developing other largely non-fatal but disabling consequences of diabetes such as renal failure and vision loss.

• Australia is likely to benefit from further efforts towards expanding the range of effective prevention and treatment strategies for all causes of burden, while recognising that the returns for these efforts can take time to be realised. Only in recent years, for example, have smoking-related cancers started to decline as the result of several decades of successful tobacco control programs.

9

1 Introduction

1.1 Purpose

The study upon which this report is based is the first complete assessment of the health of Australians in the new millennium and the second study in this country with comparable objectives. The original study, the results of which continue to be used widely in policy and research environments, was conducted by the Australian Institute of Health and Welfare (AIHW: Mathers et al. 1999) and provided a comprehensive overview of disease and injury burden for the year 1996. Increasing demand for a contemporary picture of health status in Australia led, in 2003, to an Australian Government-funded collaboration between the University of Queensland and the Australian Institute of Health and Welfare (AIHW), the aim of which was to update and expand the original work.

The objectives of this collaboration were to report on the following:

• full burden of disease and injury results for the year 2003 by age group, sex and cause

• projections of disease and injury burden 20 years into the future

• improved models for attributing disease and injury burdens to risk factors

• sub-national estimates of burden for state and territory jurisdictions, socioeconomic quintiles, remoteness categories and small areas

• the burden of disease and injury in Aboriginal and Torres Strait Islander populations.

This report presents the main findings of this collaboration and meets the above objectives, except the last which is covered in a separate report.

1.2 Background

Changes in demography and technology are placing increasing pressure on the health

budgets of developed countries around the world. Mortality and fertility rates have

decreased consistently over recent decades, resulting in increases in life expectancy and the

proportion of total population alive at old and very old ages (AIHW 2006). In addition,

developments in knowledge and medical technology are contributing to a growing demand

for health services and, in many cases, to higher costs of providing these services. In

Australia and elsewhere, these factors have brought into focus the need for more rigorous

debate about how health systems can achieve their dual objectives of maximising health

gains for given levels of expenditure and maintaining fair and equitable access to health

services.

Improving the evidence base that informs this debate is critical if health systems are to be

meaningfully held to account. Such an agenda requires contributions from a number of

areas, including:

• detailed assessments of the size and impact of health problems in a population,

including information on the causes of loss of health in the population (in terms of both

diseases and injury, and risk factors or broader determinants)

10

• information on inequalities in health status, health determinants, and access to and use

of health services (including prevention and treatment services)

• information on health expenditure and health infrastructure (a national system of health

accounts) detailing the availability of resources for health improvement and the current

use of these resources

• information on the cost-effectiveness of available technologies and strategies for

improving health

• information on current levels of investment in health research and development, and on

the opportunities for investment with the greatest likelihood of developing new or

improved interventions that best remedy major health problems.

This report contributes to the development of such an agenda in Australia by providing a

detailed and internally consistent assessment of the incidence, prevalence, duration,

mortality and burden for an exhaustive and mutually exclusive set of major diseases and

injuries experienced in this country. The burden from these causes is quantified for various

subpopulations, risks to health and points in time using a summary measure of population

health that combines both fatal and non-fatal health outcomes, and includes comorbidity

adjustments to account for individuals who simultaneously experience multiple conditions.

This assessment provides an unprecedented level of detail on the magnitude and

distribution of health problems in contemporary Australia. Although solutions to these

problems are not addressed explicitly in the following chapters, the analyses described

encompass a methodology that is increasingly being used in Australia and elsewhere to

assess health outcomes both for descriptive purposes and in comparative analyses of the

costs and effectiveness of particular health interventions. The report can be regarded,

therefore, as an important foundation for further work on improving health system

performance in Australia.

1.3 Summary measures of population health

Summary measures of population health are measures that combine information on

mortality and non-fatal health outcomes into a single number to represent one or more

dimensions of health at a population level (Field & Gold 1998). In the past 15 years, there has

been a marked increase in interest in the development, calculation and use of summary

measures. The range of potential applications includes:

• comparing health conditions or overall health status between two populations or the

same population over time

• quantifying health inequalities

• ensuring that non-fatal health outcomes receive appropriate policy attention

• measuring the magnitude of different health problems using a common currency

• analysing the benefits of health interventions for use in cost-effectiveness studies

• providing information to help set priorities for health planning, public health programs,

research and development, and professional training (Murray et al. 1999b).

Most summary measures fall into one of two broad groups: health ‘expectancies’ and health

‘gaps’. Both groups use time (either lived in health states or lost through premature death

and illness) as the unifying ‘currency’ for combining the impact of mortality and non-fatal

health outcomes. Another common feature is the requirement for explicit or implicit choices

11

in their application: mortality-based indicators, for example, exclude considerations

regarding non-fatal loss of health; indicators of potential years of life lost ignore deaths

beyond an arbitrary age (for example 65 years); and indicators of disability-free life

expectancy do not place any positive value on years lived with disability.

Health ‘gap’ measures, in particular, quantify the gap between a population’s actual health

status and some ‘ideal’ or reference status. The most widely known example of such a

measure, and the one used in this report, is the disability-adjusted life year or DALY.

Another measure commonly used in economic evaluations but not in population health

status assessments is the Quality Adjusted Life Year (QALY).

1.4 Disability-Adjusted Life Years

The DALY was first developed to provide information to support health policy and priority

setting at a global level. The concept was developed as part of a comprehensive assessment

of global health for the year 1990 in what became known as the Global Burden of Disease or

GBD study (Murray & Lopez 1996a, 1996b; World Bank 1993). It has since become

synonymous with ‘burden of disease’ and the terms tend to be used interchangeably.

The DALY was originally intended to:

• allow estimates of health effects to be mapped to causes, either in terms of disease and

injury, or risk factors and broader social determinants

• provide a common measure for estimating population health effects and

cost-effectiveness of interventions

• use common values and health standards for all regions of the world

• provide a common measure for fatal and non-fatal health outcomes.

In this way, the DALY extends the concept of potential years of life lost due to premature

death (PYLL) by including equivalent years of ‘healthy’ life lost by virtue of being in states of

poor health or disability. A DALY for a disease or health condition is calculated as the sum

of the years of life lost due to premature mortality (YLL) in the population and the

equivalent ‘healthy’ years lost due to disability (YLD) for incident cases of the health

condition:

DALY = YLL + YLD

where YLL = number of deaths x standard life expectancy at age of death and

YLD = incidence x duration x severity weight.

The loss of healthy life due to health conditions (YLD) requires estimation of the incidence of

the disabling health condition (disease or injury) in the specified time period. For each new

case, the number of years of healthy life lost is obtained by multiplying the average duration

of the condition (to remission or death) by a severity weight that quantifies the equivalent

loss of healthy years of life due to living with the health condition or its sequelae. The YLD is

as an incidence-based measure, therefore, which captures the future health consequences of

new cases of disease and injury that occur in the baseline year (2003 in this study). Such a

measure, when combined with YLL, enables the full ‘health loss’ of different diseases and

injuries to be compared and has most application in planning.

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Alternatively, health loss can be measured by counting it at the age it is lived. This is the

‘prevalent burden’ or prevalent years lost due to disability (PYLD) and is calculated thus:

PYLD = prevalence x severity weight

Prevalent burden is useful from a service utilisation or expenditure perspective and

measures the amount of disability (but not the fatal burden) being experienced in a

population at a point in time.

From the perspective of the International Classification of Functioning, Disability and Health

(ICF) (see <www3.who.int/icf/icftemplate.cfm>) the YLD measures the impact of a health

condition on an individual’s functioning, now and into the future. Functioning includes the

functional and structural integrity of the human body as well as activities undertaken by

people and participation in life situations.

Interpreting the DALY

The DALY methodology provides a way to link information on disease causes and occurrence to

information on both short-term and long-term health outcomes, including activity limitations and

restrictions in participation in usual roles, and death. The burden of disease methodology is designed

to inform health policy about the prevention and treatment (cure or reduction in severity) of adverse

health outcomes. It is not designed to inform policy for the provision of social support or welfare

services for people with long-term disability.

When using the DALY for the first time, Murray and Lopez sought to make explicit the value

choices that they had to make in their application of a summary measure at a global level.

For example, they chose to use the same life expectancy ‘ideal’ standard for all population

subgroups across the globe, whether or not their current life expectancy was lower than that

of other groups. They also excluded all non-health characteristics (such as race,

socioeconomic status or occupation), apart from age and sex, from consideration in

calculating lost years of healthy life. Most importantly, they used the same severity weight

for everyone living a year in a specified health state. These and other aspects of the DALY

are described in further detail in Chapter 2.

1.5 Burden of disease analysis in Australia

Since its introduction, burden of disease analysis has been applied in an increasing number

of international and national settings; for example, it was used for a period by the World

Health Organization (WHO) to inform global health planning (WHO 2002). Burden of

disease analysis has a particularly strong history in Australia. The first study by the AIHW

assessed the burden of disease and injury in Australia for the year 1996 (AIHW: Mathers et

al. 1999). Starting in June 1998, the first study was partly funded by the then Commonwealth

Department of Health and Aged Care and was conducted in parallel with a state-level

analysis for Victoria by the Victorian Department of Human Services (DHS 1999a, 1999b).

Both project teams worked together closely on methods and analyses.

This work represented the first attempt to carry out a systematic and comprehensive analysis

of over 170 disease and injury categories in this country. It also substantially extended the

13

international work on burden of disease in many areas, as shown by the fact that a number

of its methodological advancements were subsequently picked up in the GBD 2000 work at

WHO (Mathers et al. 2004). Since then, burden of disease analysis has been undertaken in

most jurisdictions throughout Australia, at varying levels of detail. The update of the

Victorian Burden of Disease study for the year 2001 (DHS 2005) deserves special mention as

a number of disability models and data sources were shared between the researchers

working on that project and those working on the present study.

This study was conducted in close consultation with relevant jurisdictional stakeholders, and

the national and jurisdictional estimates in this report are intended to complement existing

estimates from individual State and Territory based burden of disease studies. Because of

somewhat different estimating methods and data sources, the jurisdictional estimates in this

report may differ somewhat from State and Territory based estimates. This does not mean

that one estimate is more correct than the other, but reflects the uncertainties inherent in any

analysis which attempts to estimate burden for over 170 conditions.

1.6 Burden in Aboriginal and Torres Strait Islander

peoples

Findings about Aboriginal and Torres Strait Islander peoples are not covered in this report,

the primary focus of which is on the health status of Australians as a whole. This is not a

problem for most of the comparisons presented, although special caution should be taken

when interpreting the results of Chapter 5 on health differentials, particularly the estimates

for remote areas and the Northern Territory. The higher proportion of Indigenous people in

these areas explains most of the greater health loss in these areas compared with those where

the proportion of Indigenous people is lower. However, the contribution of Indigenous

populations to this loss has not been quantified in this report. Readers seeking to know such

comparisons are referred to the companion report on the burden of disease and injury in

Aboriginal and Torres Strait Islander peoples.

1.7 Structure of report

Details of the specific methodological developments of this study are presented in Chapter 2.

Chapter 3 provides an overview of the total burden of disease and injury in Australia, by

cause, age and sex. Chapter 4 provides estimates of the burden of disease and injury

attributable to selected risk factors in Australia. Chapter 5 shows how the burden of disease

and injury across Australia varies according to where people live and their socioeconomic

status. Chapter 6 presents the past, present and projected burden of disease and injury in

Australia and Chapter 7 provides a general discussion of the major findings.

Technical notes on the methods used for estimating non-fatal health outcomes and

attributing risk are presented in Appendixes 1 and 2, respectively. Annex table 1 summarises

the disease and injury categories used and their respective International Classification of

Diseases codes. Annex table 2 summarises the primary data sources used to construct the

core set of results. Tabulations of the core results are included in Annex tables 3 to 9. More

detailed tabulations of the core results are available in Annex tables 10 to 25, which are

available on the web at <www.aihw.gov.au/bod>.

14

Readers should note that every attempt was made to identify the best available information

in the preparation of this report, and to consult as widely as possible on decisions about

methods, assumptions and data sources. For some aspects of the study, however, it was not

possible with the resources available to go beyond simple models and assumptions about

some key parameters. For many disease models, not all required information was available

and analyses drew on information from overseas or expert opinion. In the projections work,

trends in disease occurrence were nonexistent for many conditions. The results presented in

the following chapters, therefore, represent a complex synthesis of information, judgment

and, in some cases, even speculation. It is hoped that further improvements over time in

methods, models and data will result in increasing accuracy and certainty in estimates of

burden of disease and injury in Australia. The authors at the University of Queensland and

the Australian Institute of Health and Welfare welcome suggestions for such improvements.

15

2 Methodological developments

This chapter discusses the key methodological considerations that underpin the findings

presented throughout the report. Readers who are only interested in these findings can skip

to chapters 3 through 7 and return to this chapter at a later time. Those wishing to

understand the ways in which the methodological challenges were resolved are encouraged

to read on. The chapter begins by outlining some solutions to various methodological issues

that are unavoidable in the application of the burden of disease and injury framework,

including social value choices, causal attribution and comorbidity. It concludes with a

description of the specific methods that were adopted to derive the findings on risks to

health, burden across time and differentials in burden.

2.1 Social value choices

The burden of disease and injury framework encompasses some obviously normative

characteristics (that is, it incorporates certain value judgments about how things ought to be).

This is because its main measure (the disability-adjusted life year or DALY) comprises only a

selection of all possible parameters that could be used to characterise health, and the

numerical weighting given to each parameter implies a judgment about its relative

importance to the total measure. These judgments have come to be known collectively as

‘social value choices’. While the implications of certain choices over others are important and

sometimes contested, as reflected by the growing literature in this area (Anand & Hanson

1997; Reidpath et al. 2003; Williams 1999), such considerations are beyond the scope of this

chapter. The purpose here is to provide a brief discussion of the key choice that differs from

the previous study. Readers are referred elsewhere for a more in-depth discussion on the

merits of the other social value choices (Murray et al. 2002).

As mentioned in the previous chapter, the DALY is a health gap measure that requires an

ideal against which to quantify the gap between current patterns of mortality and a

counterfactual scenario in which all mortality is averted until very old age. The steering

committee of the previous Australian Burden of Disease and Injury Study requested that

projected life expectancy, based on a cohort life table (which takes into account past trends in

mortality) for Australia, be used to define the mortality ‘gap’ for the purposes of calculating

the years of life lost due to premature mortality (YLL). Until then, the standard that had been

used in all burden of disease studies was based on the Coale and Demeny West level 26

model life table (Coale & Guo 1989), chosen after observing the highest life expectancy

recorded for any nation (82.5 years for women in Japan at the time). It was then assumed

that the minimum male–female ‘biological’ difference in survival potential was in the order

of 2.5 years, but because there was no male schedule with a life expectancy of 80 years, the

standard for males was based on the Coale and Demeny West level 25 schedule for females

(Murray & Lopez 1996a).

The cohort life tables for Australia used in the 1996 study and the standard life tables used in

other studies are very similar, and the substitution of one for the other would have had little

effect on the final results. This is particularly true for discounted YLL, where the small

differences in time lost would have been even further reduced by a time discount rate of 3%,

although some differences were observable if undiscounted YLL were compared. For the

current study, however, the situation is complicated by the fact that life expectancy in

16

Australia has changed since 1996 (an increase of 0.25 years and 0.3 years per annum for

females and males, respectively). If the projected cohort life expectancy were to be used

again, the mortality gap would be somewhat different because the projected cohort life

expectancy based on changes in mortality rates to 2003 would be different from the old

cohort life expectancy, which was based on changes in mortality rates to 1996. While the

difference is not great, it does not aid comparisons to have a standard that is continually

changing. Thus the current advisory committee has recommended a return to the

internationally recognised standard used in most other burden of disease studies.

It is worth noting here that the life table for a population that actually achieves the ‘ideal

standard’ (that is, no mortality until age 82.5 in females and 80 in males) would be very

different from the standard life table. It is best to view the choice of the standard life table,

therefore, as a weighting for age at death, without reference to the properties of the life table

used to derive these weights.

All other social value choices remain as they were in the previous study (Table 2.1): uniform

age weights and a discount rate of 3% were applied, and a combination of disability weights

from the original GBD study (Murray & Lopez 1996a) and the Disability Weights for

Diseases in the Netherlands study (Stouthard et al. 1997) were used. For some health states,

there was no equivalent in either the Dutch or GBD set of weights, or the weights that appear

in the published material seemed implausible. In these instances, the weights that were

specifically derived for the previous Australian studies were applied. Unfortunately, a study

to determine local weights for the range of health states most relevant to Australia was not

able to be done. The complete list of weights is available at <www.aihw.gov.au/bod>.

Table 2.1: Social value choices used in the calculation of DALYs, 1996 study and present study

Choice 1996 study Present study

Mortality counterfactual Projected life expectancy based on

cohort life tables for Australia in 1996

International standard first reported in Murray &

Lopez 1996a

Age weighting Uniform Uniform

Discount rate 3% 3%

Source of disability

weights

Murray & Lopez 1996a,

Stouthard et al. 1997 and locally derived

Murray & Lopez 1996a,

Stouthard et al. 1997 and locally derived

17

Box 2.1: Interpreting a disability weight

To place a value on the time lived in non-fatal health states, health state weights are used to formalise

and quantify social preferences for different states of health. Depending on how these weights are

derived, they are referred to as disability weights, quality-adjusted life year (QALY) weights, health

state valuations, health state preferences or health state utilities. QALY weights are measured as a

number on a scale of 0 – 1, where 0 is assigned to a state comparable to death and 1 is assigned to a

state of ideal health. This assignment for the DALY (where 0 = perfect health and 1 = death) is the

complement to 1, compared to that used for the QALY, because the QALY measures equivalent

healthy years lived, whereas the DALY measures loss of health.

Although the disability weights used in DALY calculations quantify societal preferences for different

health states, the weights do not represent the lived experience of any disability or health state, or

imply any societal value for the person in a disability or health state. Rather, they quantify societal

preferences for health states in relation to the societal ideal of good health. Thus, a weight for

paraplegia of 0.57 does not mean that a person in this health state is ‘half-dead’, that they experience

their life as halfway between life and death, or that society values them less as a person compared

with ‘healthy’ people. It means that, on average, society judges a year with blindness (weight 0.43) to

be preferable to a year with paraplegia (weight 0.57), and a year with paraplegia to be preferable to a

year with unremitting unipolar major depression (weight 0.76). It also means that, on average,

society would prefer a person to have a year in good health followed by death than a year with

paraplegia followed by death. Society would also prefer to restore a person with paraplegia to good

health rather than restore a person’s sight if the costs of cure are the same for the two interventions.

2.2 Causal attribution

There are two traditions for causal attribution of health outcomes or states: categorical

attribution and counterfactual analysis (Mathers et al. 2001). In categorical attribution, an

event such as death is attributed to a single cause (such as a disease or risk factor) or group

of causes according to a defined set of rules, such as the International Classification of

Disease (ICD) system for attributing causes of death (WHO 1992). In counterfactual analysis,

the contribution of one or a group of risk factors to disease or mortality is estimated by

comparing the current or future disease burden with the levels that would be expected under

some alternative hypothetical scenario (referred to as the counterfactual). This study uses

both approaches: categorical attribution for attributing burden to diseases and injuries,

which is discussed below, and counterfactual analysis for attributing burden to more distal

risks to health, which is discussed in a subsequent section.

Estimates of burden are typically attributed to a comprehensive set of disease and injury

‘entities’ (for example ischaemic heart disease or falls). These entities represent the smallest

unit of disaggregation in the analysis and are referred to in this report as ‘specific causes’ or

‘conditions’. Each entity is mutually exclusive and belongs to one of a number of ‘broad

cause groups’, most of which correspond to chapter-level headings of the ICD (for example

cardiovascular disease or intentional injuries). Each broad cause group, in turn, belongs to

one of three broad clusters:

• Group I: Communicable, maternal, neonatal and nutritional conditions

• Group II: Non-communicable diseases

• Group III: Injuries.

18

Annex Table 1 defines the classifications used in this study in terms of ICD-10 codes, most of

which are consistent with the classifications used by WHO in the GBD2000 project (Mathers

et al. 2004). A comparison of the ICD-10 list and the one based on ICD-9 used in the

previous study is available at <www.aihw.gov.au/bod>.

Categorising deaths

The ICD has its origins in the preparation of mortality statistics, and standard death statistics

use the categorical approach to causal attribution. While any number of conditions may be

recorded on a death certificate, the ICD allows for only one to be selected for primary

tabulation purposes. This single cause is referred to as the ‘underlying cause of death’ and is

intended to represent the condition, event or circumstances without the occurrence of which

the person would not have died. The concept of underlying cause has been central to

mortality coding and comparable international mortality reporting over the 100-year period

that the ICD has been used for such purposes.

Box 2.2: Death registration in Australia

Registration of deaths in Australia is the responsibility of the state and territory Registrars of Births,

Deaths and Marriages. Information on the cause of death is supplied by the medical practitioner

certifying the death or a coroner. Other information about the deceased is supplied by a relative or

other person acquainted with the deceased or by an official of the institution where the death

occurred. Registration of death is a legal requirement in Australia, and compliance is almost

complete. The information is provided by the Registrars to the Health and Vitals Unit at the

Queensland office of the Australian Bureau of Statistics (ABS) for coding and compilation into

national statistics. The ABS began automated coding of death certificates using software known as

the Mortality Medical Data System (MMDS) in 1997 and has made available multiple causes of

death data coded in ICD-10 for all years since that time. Before 1997, only underlying cause of death

data are available. The MMDS was developed by the National Center for Health Statistics in the

United States of America to facilitate the coding of all causes of death reported on death certificates,

and the designation of the underlying cause of death according to ICD criteria.

The availability of an unambiguous set of rules, such as can be found in the ICD, does not

alter the fact that the accuracy of the information to which these rules are applied is

dependent on several factors: the availability and quality of the clinical evidence at the time

of certification; the thoroughness and diligence with which physicians and coroners record

this information on the death certificate; and the quality of the system used to transcribe

information from death certificates and translate this information to ICD codes. Australia is

regarded as having a high-quality system of registration by international standards and this

is reflected by one measure of quality, the proportion of total deaths coded to non-specific

underlying causes of death. The small amount of non-specific coding that does occur is

confined mainly to the ill-defined sections of the cardiovascular disease, cancer and injury

chapters, with only a very small proportion of deaths being coded to the general signs and

symptoms chapter. However, with the exception of a few studies on sensitivity and

specificity in relation to specific conditions, relatively little is known about the frequency

with which Australian doctors attribute the correct underlying cause to the majority of

deaths. It is likely that accuracy varies with the location of the death (for example in an

19

institutional setting versus at home), but the assumption that inaccuracies tend to cancel each

other out at the population level is largely speculative and is an area deserving of further

research.

While this study largely followed the ICD concept of ‘underlying cause’ in the categorisation

of deaths, in some cases deaths were reallocated to more specific or different categories to

ensure consistency with the estimates for years lost due to disability (YLD). For example, the

proportion of liver cancer and liver cirrhosis mortality that is attributable to hepatitis was

redistributed to the hepatitis B and hepatitis C categories in the core results. Similarly, data

on the underlying cause of renal failure from the Australia and New Zealand Dialysis and

Transplant Registry (ANZDATA) was used to redistribute renal failure deaths to nephritis &

nephrosis, diabetes mellitus, injuries, congenital conditions, cancers and infectious diseases.

It is important to note that for many conditions there is a difference between the number of

deaths attributed to the disease and amount of excess mortality that occurs in prevalent cases

of the disease. This is often due to comorbidity and the fact that diseases may cluster in

people exposed to the same risk factors that also affect the risk of dying from other causes.

Examples of this are schizophrenia, where part of the excess risk is due to the high

prevalence of smoking and diseases associated with the usually lower socioeconomic status

of people with chronic and severe mental disease; and cardiovascular disease, where the

main lifestyle risk factors also increase the risk of dying from diabetes and some cancers.

For the overall cause of death structure presented in this report, recorded underlying causes

of death were used, subject to the redistribution algorithms discussed below. In the disease

modelling discussed in Appendix 1, however, best available estimates of excess mortality

were used in order to derive the most accurate estimates of disease duration.

Redistributing non-specific causes of death

In keeping with established ‘burden of disease’ methods, attempts were made to remove

possible distortions to the reported overall cause of death structure by reallocating deaths

with certain codes known to be problematic to valid and specific underlying causes of death.

The rationale for not taking reported causes of death at face value is that policy objectives are

best served by information that is corrected for possible sources of systematic bias. By world

standards, the extent of distortions in cause of death information in Australia is small

(around 6–10%, depending on what codes are included in this definition). In some areas,

however, there are obvious anomalies that require specific attention.

Murray and Lopez (1996a) were the first to provide convincing evidence that a significant

and varying proportion of ischaemic heart disease deaths are coded in many countries to

ill-defined codes such as heart failure. They argued that this, in part, helps to explain the

French paradox in which mortality from ischaemic heart disease in France is comparatively

low despite high levels of exposure in the French population to risks known to be associated

with this disease. In fact, many ischaemic heart disease deaths are most probably being

coded to heart failure or other equally non-specific cardiovascular causes. Policy is better

served by correcting this misclassification error.

Various redistribution algorithms to correct non-specific cause of death coding have been

developed in response to these considerations throughout the world. In the previous

Australian Burden of Disease and Injury Study, for example, a number of decisions were

made about what to do with problem coding based on local considerations regarding the

cause of death collection system at the time. One of the guiding principles of the present

20

study was not to change past decisions such as these unnecessarily, unless there were

compelling reasons to do so, such as new evidence.

In the period since the completion of the previous study, the vital registration system in

Australia has changed in two significant respects. First, the ABS moved from the coding of

mortality using version 9 of the ICD to version 10 in 1997. Second, at the same time, the ABS

implemented automated coding of mortality statistics using software developed in the

United States. The use of this system allows multiple cause of death coding (that is, coding of

the underlying cause of death as well as all other associated causes recorded on the death

certificate by the certifying medical practitioner), significantly enhancing the amount of

information on official mortality files (see Box 2.2). To facilitate an assessment of the impact

of these changes, the ABS retained the old system of coding for a period of two years, thus

providing an invaluable resource for researchers trying to assemble comparable data on

causes of death in Australia over time.

The availability of this additional information has allowed known problematic codes to be

examined in much greater detail than has been possible in the past. It has also allowed the

identification of some areas where possible new coding anomalies are emerging. The most

glaring of these is the much greater number of deaths being coded to pneumonia under the

new system. In the seven years to 1997, there were around 1,700 deaths from this condition

annually. With the advent of automated coding, this number has risen to around 3,300

deaths annually. Such dramatic shifts are not due to changes in underlying disease

frequency, but are rather an artefact of a greater preference under the new system to code

deaths to this category (manual coders, on the other hand, were probably more likely to

attribute an underlying chronic condition). Rather than correcting for this large

discontinuity, which would then need to be repeated in the future to ensure comparability,

the coding for these deaths was left unchanged. This explains the rapid rise in lower

respiratory tract infections from 1993 to 2003 described in Chapter 6.

The other area where a discontinuity of this magnitude is apparent is the greater

preponderance under the new system to code deaths due to external causes to ‘exposure to

unspecified factor’ (ICD-10 code X59). Analysis of the dual-coded data revealed that the

majority of these deaths in the elderly were in fact coded to ‘falls’ under the old system. In

this instance, an additional allocation algorithm was applied whereby deaths coded to this

category (around 0.6% of all deaths) were reallocated to ‘falls’ if they also had a ‘fracture’

code in the multiple cause of death data (AIHW: Cripps & Carman 2001). This approach was

also used for ‘unspecified septicaemia’ (ICD-10 code A419), whereby deaths in this category

(again, around 0.6% of all deaths) were reallocated to ‘nephritis & nephrosis’ if they also had

an ‘acute renal failure’ code (ICD-10 code N17).

Another area where the new system may be in error is in the assigning of inappropriate

underlying causes where another code would have been more informative. For example, in

the 7-year period to 2003, 548 deaths were coded to tobacco dependence as an underlying

cause. Likewise, 885 deaths were coded to obesity and 2,072 to hypercholesterolaemia and

dyslipidaemia over the same period. These codes are most appropriately regarded as risk

factors for more specific underlying disease processes and preferably should not be used in

primary underlying cause of death tabulations. The number of deaths coded to these

categories is likely to substantially underestimate the true mortality attributable to these

risks (which is estimated in this report using very different methods, as discussed in

Appendix 2). Deaths coded to tobacco dependence were therefore redistributed across lower

respiratory tract infections, mouth and oropharynx cancers, lung cancer, ischaemic heart

disease, stroke, other cardiovascular disease, chronic obstructive pulmonary disease (COPD)

21

and other chronic respiratory diseases based on a probability analysis of multiple-cause

information over the period 1997 to 2003. Obesity was allocated to ‘other endocrine &

metabolic disorders’ and the other two codes (about 300 deaths per year) to ‘ill-defined

cardiovascular disease’, which was ultimately reapportioned to specific cardiovascular

diseases (largely ischaemic heart disease).

The probability approach using multiple causes of death information was also applied to two

other categories: ‘ill-defined nutritional’ (ICD-10 codes E64 and E639) and ‘essential

hypertension’ (ICD-10 code I10). The first (representing 0.1% of all deaths) was redistributed

across lower respiratory tract infections, other endocrine & metabolic disorders, dementia,

other chronic respiratory diseases, and nephritis & nephrosis. The second (accounting for

0.2% of all deaths) was redistributed across all specific cardiovascular diseases.

Useful though it is, multiple cause of death information provides no new insights about

three known problematic areas: ill-defined cancer, ill-defined injury and ill-defined

non-injury deaths. It turns out that these deaths are assigned non-specific codes precisely

because there is very little other information of relevance either on the death certificate or

through coronial investigations (in the case of external causes) to make a more accurate

determination. In the previous study these causes were allocated to specific cause groupings

on a pro-rata basis on the assumption that the proportional distribution within these

groupings reflected the most likely probabilities for causal attribution to a specific cause.

There is no new evidence to alter these decisions. These causes and the cause groupings to

which they were proportionately redistributed are listed in Table 2.2.

Table 2.2: Ill-defined causes of death and specific cause groupings to which they were allocated on

a pro rata basis

Ill-defined cause(a) Per cent of all causes Specific cause groupings(a)

Ill-defined malignant neoplasms(b) 1.92 All specific cancer sites

Uterus cancer—unspecified(b) 0.04 Cervix cancer

Corpus uteri cancer

Other anaemias 0.06 Haemolytic anaemia

Other non-deficiency anaemia

Ill-defined non-injuries (i.e. diseases)(a) 0.39 All specific non-injury causes

Ill-defined unintentional accidents (no

fracture)(b) 0.11 All specific unintentional injury causes

(a) Refer to Annex Table 1 for the ICD-10 codes that correspond to these cause categories.

(b) Denotes a redistribution decision derived from the previous Australian Burden of Disease and Injury Study.

Based on an assessment of cause of death statistics in Australia over a 25-year period,

including the seven years of multiple causes of death information to 2003, a number of

redistribution decisions were retained from the previous study, largely because there was no

compelling reason to do otherwise. The list of these causes and the corresponding specific

causes to which they are proportionately redistributed is outlined in Table 2.3.

22

Table 2.3: Ill-defined causes of death and percentage allocation to specific causes

Allocation to specific causes (%)(a)

Ill-defined cause(a)

Deaths in ill-defined

causes as % of all causes

Chlamydia

Other STD

Hepatitis B

Hepatitis C

Birth trauma & asphyxia

Low birth weight

Neonatal infections

Other perinatal

Type 1 diabetes

Type 2 diabetes

Nephritis & nephrosis

Peptic ulcer disease

Cirrhosis of the liver

Ischaemic heart disease

Inflammatory heart disease

Hypertensive heart disease

Other cardiovascular disease

Suicide &self-inflicted

injuries

Homicide & violence

Road traffic accidents

Poisoning

Falls

Fires/burns/scalds

Drowning

Other unintentional injuries

Pelvic inflammatory disease(b) 0.01 60 40 — — — — — — — — — — — — — — — — — — — — — — —

Hepatitis sequelae(b) 0.07 — — 50 50 — — — — — — — — — — — — — — — — — — — — —

Neonatal deaths coded to

maternal condition(c) 0.26 — — — — 16 56 6.6 21 — — — — — — — — — — — — — — — — —

Unspecified diabetes mellitus(b) 1.32

Males 0–14 years — — — — — — — — 100 — — — — — — — — — — — — — — — —

Males 15–24 years — — — — — — — — 89 11 — — — — — — — — — — — — — — —

Males 25–34 years — — — — — — — — 79 21 — — — — — — — — — — — — — — —

Males 35–44 years — — — — — — — — 33 67 — — — — — — — — — — — — — — —

Males 45–54 years — — — — — — — — 9.8 90 — — — — — — — — — — — — — — —

Males 55–64 years — — — — — — — — 5.5 95 — — — — — — — — — — — — — — —

Males 65+ years — — — — — — — — 2.8 97 — — — — — — — — — — — — — — —

Females 0–14 years — — — — — — — — 100 — — — — — — — — — — — — — — — —

Females 15–24 years — — — — — — — — 75 25 — — — — — — — — — — — — — — —

Females 25–34 years — — — — — — — — 56 45 — — — — — — — — — — — — — — —

Females 35–44 years — — — — — — — — 42 58 — — — — — — — — — — — — — — —

Females 45–54 years — — — — — — — — 16 84 — — — — — — — — — — — — — — —

(continued)

23

Table 2.3 (continued): Ill-defined causes of death and percentage allocation to specific causes

Allocation to specific causes (%)(a)

Ill-defined cause(a)

Deaths in ill-defined

causes as % of all causes

Chlamydia

Other STD

Hepatitis B

Hepatitis C

Birth trauma & asphyxia

Low birth weight

Neonatal infections

Other perinatal

Type 1 diabetes

Type 2 diabetes

Nephritis & nephrosis

Peptic ulcer disease

Cirrhosis of the liver

Ischaemic heart disease

Inflammatory heart disease

Hypertensive heart disease

Other cardiovascular disease

Suicide & self-inflicted

injuries

Homicide & violence

Road traffic accidents

Poisoning

Falls

Fires/burns/scalds

Drowning

Other unintentional injuries

Females 55–64 years — — — — — — — — 8.1 92 — — — — — — — — — — — — — — —

Females 65+ years — — — — — — — — 4.7 95 — — — — — — — — — — — — — — —

Hypertensive heart and renal

disease(b) 0.10 — — — — — — — — — — 50 — — — — 50 — — — — — — — — —

Heart failure(b) 2.10

Persons 0–4 years — — — — — — — — — — — — — — — — 100 — — — — — — — —

Persons 5–29 years — — — — — — — — — — — — — — 75 — 25 — — — — — — — —

Persons 30–44 years — — — — — — — — — — — — — 70 25 5 — — — — — — — — —

Persons 45–59 years — — — — — — — — — — — — — 70 5 25 — — — — — — — — —

Persons 60+ years — — — — — — — — — — — — — 60 10 30 — — — — — — — — —

Ill-defined cardiovascular

conditions(b) 0.94

Persons 0–59 years — — — — — — — — — — — — — 75 — — 25 — — — — — — — —

Persons 60+ years — — — — — — — — — — — — — 80 — — 20 — — — — — — — —

Gastric haemorrhage(b) 0.24 — — — — — — — — — — — 50 50 — — — — — — — — — — — —

Road traffic accidents—intent

undetermined(b) 0.00

Persons 0–14 years — — — — — — — — — — — — — — — — — — 100 — — — — — —

(continued)

24

Table 2.3 (continued): Ill-defined causes of death and percentage allocation to specific causes

Allocation to specific causes (%)(a)

Ill-defined cause(a)

Deaths in ill-defined

causes as % of all causes

Chlamydia

Other STD

Hepatitis B

Hepatitis C

Birth trauma & asphyxia

Low birth weight

Neonatal infections

Other perinatal

Type 1 diabetes

Type 2 diabetes

Nephritis & nephrosis

Peptic ulcer disease

Cirrhosis of the liver

Ischaemic heart disease

Inflammatory heart disease

Hypertensive heart disease

Other cardiovascular disease

Suicide & self-inflicted

injuries

Homicide & violence

Road traffic accidents

Poisoning

Falls

Fires/burns/scalds

Drowning

Other unintentional injuries

Persons 15+ years — — — — — — — — — — — — — — — — — 90 — 10 — — — — —

Falls—intent undetermined(b) 0.01

Persons 0–14 years — — — — — — — — — — — — — — — — — — 100 — — — — — —

Persons 15+ years — — — — — — — — — — — — — — — — — 90 — — 10 — — — —

Poisoning—intent 0.04

Persons 0–14 years — — — — — — — — — — — — — — — — — — 100 — — — — — —

Persons 15+ years — — — — — — — — — — — — — — — — — 90 — — — 10 — — —

Burns—intent undetermined(b) 0.00

Persons 0–14 years — — — — — — — — — — — — — — — — — — 100 — — — — — —

Persons 15+ years — — — — — — — — — — — — — — — — — 90 — — — — 10 — —

Drowning—intent 0.01

Persons 0–14 years — — — — — — — — — — — — — — — — — — 100 — — — — — —

Persons 15+ years — — — — — — — — — — — — — — — — — 90 — — — — — 10 —

Other accidents—intent 0.00

Persons 0–14 years — — — — — — — — — — — — — — — — — — 100 — — — — — —

Persons 15+ years — — — — — — — — — — — — — — — — — 90 — — — — — — 10

(a) Refer to Annex Table 1 for the ICD-10 codes that correspond to these cause categories.

(b) Denotes a redistribution decision derived from the previous Australian Burden of Disease and Injury Study

(c) Denotes neonatal deaths coded to maternal conditions (ICD-10 codes P00–P02) and subsequently redistributed back to neonatal causes based on an analysis of dual-coded data.

25

Alternative categories

In order to present the burden for mutually exclusive categories, decisions had to be made

on how to classify sometimes closely linked conditions while still adhering to ICD rules.

Chapter 3, however, presents alternative calculations of the burden (Table 3.20) due to

certain disease entities that otherwise are split across a number of categories in the main

disease and injury tabulations. The three entities are intellectual disability, renal failure and

vision disorders, although other groupings are also possible (for example heart failure).

Underlying causes of intellectual disability are various and include Down syndrome, central

nervous system defects, birth trauma, low birth weight, infection, injury, brain tumours,

chromosomal causes, epilepsy and autism. Renal failure can be attributed to diabetes, some

cancers, congenital conditions and injury.

Alternative calculations are also presented for diabetes and depression & anxiety because

these conditions are themselves risk factors for other causes of disability. The alternative

estimate for diabetes includes the proportion of burden from ischaemic heart disease and

stroke that is due to this disease. Likewise, for depression & anxiety the proportions of

ischaemic heart disease and suicide caused by this condition are attributed. A new approach

in this study, also, is that suicide is attributed to a range of mental and substance use

disorders rather than to depression alone. These alternative calculations appear under the

relevant disease or injury group subheading.

2.3 Comorbidity and health

It is not uncommon for two or more conditions to occur simultaneously in a person, either by

chance or because the conditions are related to each other. This is referred to as

‘comorbidity’. Independent comorbidity is the situation where the probability of having two

or more conditions simultaneously equals the product of the probabilities for having each of

the conditions. Dependent comorbidity, on the other hand, refers to the situation where the

probability of having two or more diseases is greater than the product of the probabilities for

each disease, reflecting common causal pathways (for example common risk factors causing

both diabetes and heart disease) and also that one disease may increase the risk of another.

Both types of comorbidity are problematic for burden of disease estimation because the

available disability weights are almost exclusively derived for a condition as it exists

independently from other conditions. Little attention has been directed towards estimating

weights for comorbid (or coexisting) conditions due to the enormity of the task. The severity

of health states associated with two or more conditions in combination may not simply be

the sum of the disability weights for each of the conditions. In many cases it is likely to be

less than the sum, but in some cases there may be exacerbating effects on health of having

the combined set of conditions. For example, the experience of symptomatic grade 2

osteoarthritis of the hip and severe vision loss together is probably not as disabling as the

addition of the two weights for these health states (0.14 and 0.43, respectively). The

experience of the latter with profound deafness, however, may be equal to or even more

disabling than the summation approach would suggest.

In contrast to the GBD 1990 study, an attempt was made in the original Australian studies to

accommodate this phenomenon by adjusting the disability weights for the 21 most common

non-fatal conditions of older age (for example hearing loss, osteoarthritis, heart conditions,

and diabetes). A multiplicative model was used to estimate weights for comorbid conditions,

26

and the change in total weight deducted from the weight for the milder of the conditions (see

Box 2.3). Mental health problems are less prevalent at older ages, apart from dementia, and

no attempt was made to adjust for mental–physical comorbidities, although comorbidity

between mental disorders was accounted for.

A key assumption in the implementation of this adjustment procedure was that the

prevalence of a set of comorbid conditions is equal to the product of the individual

prevalences of these conditions. In other words, dependent comorbidity was not considered.

More recent work as part of the GBD 2000 study, however, suggests that dependence is

important and has a non-trivial impact on final results (Mathers et al. 2006). As a result, it

was decided to incorporate the empirical evidence, limited though it is, on disease

dependence into the overall corrections for comorbidity.

Box 2.3: Combining disability weights

The simplest approach to estimating the disability weight for the combined conditions 1 and 2 is to

assume that the health state valuations (1 – disability weight) are multiplicative, so that the

combined weight is more severe than the weight for either condition on its own but less than if they

were simply added together, and remains bounded by 0 and 1. The disability weight for the combined

conditions 1 and 2 is given by:

DW1+2 = 1 (1 DW1)Χ (1 DW2 )

This formula can be generalised to deal with more than two causes as follows:

= − Π( )

i

total i DW 1 1 DW

where Π denotes the product operator.

In the original Australian studies, this method was used to derive a composite weight for comorbid

conditions. In the case of two conditions, the weight for the most severe condition remained

unchanged, while the weight for the milder condition was deemed to be the balance of the composite

weight minus the weight for the more severe condition. For example, if a person has symptomatic

grade 2 osteoarthritis of the hip or knee (0.14) and severe vision loss (0.43), the composite weight for

both conditions is 0.51 and the adjusted weight for the osteoarthritis is 0.08.

In the current study the disability weights are proportionately reduced for each comorbid state.

The approach taken in this study was to determine the numbers of people for every

combination of causes of ill-health measured by the major Australian health surveys and in

the National Hospital Morbidity Database. While none of these data sources contained

information on every cause of interest, each overlapped in the causes they did provide

information on, at least to some degree. This allowed comorbidity to be simulated across the

full range of causes by deriving conditional probabilities on causes common to two or more

surveys and generating an artificial cohort of people based on these probabilities. The

assumption was that the correlations observed in self-report surveys and hospital diagnoses

are reasonable proxies for the co-occurrence of disability in these samples, even though these

data sources may not accurately reflect the actual levels of disease at the population level.

Unlike the previous study, this study did not incorporate a severity hierarchy of the

disability weights by causes. Instead, a proportional downward adjustment was made to the

disability weight of each coexisting cause. The proportion used to deflate individual

27

disability weights was the total adjusted disability weight divided by the total unadjusted

disability weight for each cause and all possible combinations. A further consideration that

has not been explicitly addressed in previous work is that when a disability weight changes

with advancing age (due to comorbidity corrections or for some other reason), incident YLD

should be calculated to incorporate these changes. In other words, if the duration of a

condition is 20 years, incident YLD should be calculated using the disability weight that is

relevant to each age above the age of incidence until the 20-year duration has been reached,

rather than using the weight at the age of incidence for the whole 20-year period. This

correction was implemented in the present study.

2.4 Risks to health

Reliable and comparable assessments of the impact on population of exposure to health risks

are fundamental to prevention and health promotion activities. Until relatively recently,

health risk assessment has been conducted in the context of the methodological traditions of

individual risk factors, with little regard to achieving consistency between these traditions

when combining results. In the original Australian study, for example, the criteria for

evaluating the scientific evidence on prevalence, causality and hazard size varied greatly

among the 10 health risks assessed, resulting in lack of comparability between the estimated

population health impacts of these risks.

Techniques for attributing outcomes to health risks have advanced considerably in recent

times, particularly through the contribution of the Comparative Risk Assessment (CRA)

project. This was a large-scale effort by international panels of experts under the direction of

the World Health Organization (WHO) to collect the most up-to-date information on the

prevalence of exposure to health risks and the relationship between these exposures and

health outcomes. WHO dedicated its 2002 World Health Report to describing the results of

this effort (WHO 2002), and subsequently published a two-volume book containing detailed

information on each of the 22 health risks covered by the project (Ezzati et al. 2004a, 2004b).

The key advances of the CRA approach over previous attempts to attribute burden to health

risks are:

1. A consistent theoretical framework that uses the ‘hypothetical minimum’ as the

counterfactual against which burden due to a risk is calculated.

2. Inclusion of continuous risk variables that previously were categorical in nature, that is,

taking into account the full range of risk from elevated blood pressure, serum cholesterol,

body mass index (BMI) or inadequate fruit and vegetable intake rather than defining

thresholds for hypertension, hypercholesterolaemia, underweight/obesity and low fruit

and vegetable consumption.

3. A more systematic review of the international literature on the impact of risk factors on

health outcomes, including estimates of relative risk for a unit of increase in continuous

risk factors.

4. A theoretical framework and provisional methods for estimating the joint effects of

multiple risks to health.

28

Explicit ‘counterfactuals’

Estimating the health risks associated with exposure to a particular hazard in a population is

typically undertaken with reference to an alternative or ‘counterfactual’ distribution of

exposure (for example exposed versus not exposed). While different counterfactual

distributions may be used for different purposes (Murray and Lopez (1999) identify at least

four of potential interest), an important contribution of the CRA project was to seek

consistency in the definition and use of this distribution across each of the 22 risks analysed.

In burden of disease and injury studies, the counterfactual of greatest relevance to the

question ‘How much of this health outcome is due to that exposure?’ is the ‘theoretical

minimum’ risk distribution. This is defined as the distribution of exposure that would yield

the lowest possible risk in a population (for example zero tobacco use) and is useful for

determining how much of current burden is due to past exposure to a particular hazard (the

light grey area of Figure 2.1). This is distinct from intervention analyses, which are typically

interested in how much future burden could realistically be avoided by shifting current

exposure through the implementation of a particular intervention (various scenarios

depicted in the dark grey area of Figure 2.1).

Figure 2.1: Conceptual model for health risk assessment which identifies unavoidable burden

due to past exposures (light grey), avoidable burden due to current and future exposure (dark

grey) and burden unrelated to risk (mid-grey at bottom).

c

d

Unavoidable

Disease Burden

Time

T

0

Past Future T

0%

25%

50%

75%

100%

(Theoretical

minimum)

a

b

Exposure reduction

at T

0

29

While simple enough to operationalise in the context of hazards for which absence of

exposure is indeed the lowest possible risk, the concept of ‘no exposure’ is problematic when

lack of exposure is not meaningful, as is the case for blood pressure, cholesterol and body

mass. Before the CRA project, this issue was avoided by the categorisation of these hazards

into normal and abnormal (for example hypercholesterolaemia, hypertension, overweight or

obesity). Although relevant from a clinical management perspective, this approach is likely

to underestimate the population-level attributable burden; even though the elevation in risk

at levels of exposure below these cut-points may be small, the large numbers of people at

these levels contribute substantially to total population-level risk. The approach advocated

by the CRA researchers was to respect the continuous nature of these hazards by assessing

risk across the full distribution of exposure experienced by a population. This meant

defining ‘theoretical minimum’ distributions even for hazards for which lack of exposure is

not meaningful, which they did by drawing on evidence from very low-risk populations in

the literature (Ezzati et al. 2003).

Joint risk attribution

Another area where the CRA project made an important contribution was the joint

attribution of risks. Health risk assessment before this project typically provided information

about burden attributable to a hazard in isolation from other hazards. The difficulty with this

approach is that if several analyses are added together it can appear as if more than 100% of

total burden for any one disease or injury is being accounted for by the hazards in

combination. This is not an error in the individual risk attribution method itself but rather it

is an issue of interpretation. Individual risk attribution analyses should not be added

together, although this can be a difficult message to convey, particularly when they are

presented together.

Estimating the joint effects of multiple risks is complex in practice for several reasons. First,

some of the effects of the more distal factors (for example physical inactivity) are mediated

through more proximal factors (for example via high BMI and from BMI via high blood

pressure). Estimating the joint effects of more distal and proximal factors requires knowledge

of independent hazards of the distal ones and the amount of risk mediated through proximal

risk factors. Second, the hazard due to a risk factor may depend on the presence of other risk

factors (effect modification). Third, there may be correlation between exposures to various

risk factors, because they are affected by the same distal factors and social dynamics.

The approach used to estimate joint population attributable fractions (PAFs) in this study is

based on methods developed for the CRA, in which the assumption is made that health risks

are biologically independent and uncorrelated. This is, of course, an over-simplification, as

some risks are not biologically independent (for example physical inactivity and BMI), and

various exposures are highly correlated (for example smokers also tend to be drinkers).

However, it allows the joint PAF for n number of risks to be expressed as:

joint PAF 1 (1 )

1

i

n

i

= − Π − PAF

=

where PAFi is the PAF of individual risk factors.

The second term in the right-hand side of this equation (that is, the product of all [1 – PAFi]

terms) is the fraction of burden not attributable to any of the n risk factors. One minus this

term is the fraction attributable to the combined effects of the n risk factors.

30

For instance, inadequate intake of fruit and vegetables and high BMI increase the risk of

colon cancer. Assuming there is no dependence or correlation between these two risks, if the

PAF for fruit and vegetable intake is 0.20 and the PAF for BMI is 0.10, the burden attributable

to the two risks equals 1 – ( 1 – 0.2) x ( 1 – 0.1 ) = 1 – 0.8 x 0.9 = 0.28.

Epidemiological studies on the effects of high BMI, physical inactivity, and low fruit and

vegetable consumption on cardiovascular disease risk have illustrated some attenuation of

the effects after adjustment for more proximal factors (for example blood pressure or

cholesterol) (Berlin & Colditz 1990; Blair et al. 2001; Eaton 1992; Gaziano et al. 1995; Jarrett et

al. 1982; Jousilahti et al. 1999; Khaw & Barrett-Connor 1987; Liu & Manson 2001; Manson et

al. 1990; Rosengren et al. 1999; Tate et al. 1998). This attenuation confirms that some of the

hazard of the more distal factors operates by increasing levels of risk in factors closer in the

causal pathway to the disease. The attenuation varies among studies but is consistently less

than one-half of the excess risk (that is, RR - 1) of the more distal factors. An upper bound of

50% is used in this study as the proportion of the excess risk from BMI, physical activity and

fruit and vegetable intake that is mediated through proximal factors that are themselves

among the risks being analysed. For example, if the relative risk of BMI for diabetes is 4 for a

particular level of BMI exposure, for the joint effects calculation a relative risk of (4 – 1) x 0.5

+ 1 = 2.5 is used to calculate the PAF that eventually feeds into the equation on the previous

page. Joint risk factor estimates for cardiovascular disease are not very sensitive even to large

variations in this assumption of attenuation (Ezzati et al. 2004a).

The burden attributable to both child sexual assault and intimate partner violence is

estimated in this study for the first time. Evidence suggests that girls who experience child

sexual abuse are more likely than non-abused girls to experience intimate partner violence

(Mouzos & Makkai 2004). In the joint effects analysis for these exposures, the burden due to

child sexual abuse and intimate partner violence is calculated as the sum of the PAFs for

exposure to child sexual abuse only, exposure to intimate partner violence only, and the

combined state of exposure to both risks.

2.5 Past, present and future burden

Forecasts about the future play an important role in shaping public policy. For example, an

important consequence of economic development has been improvements in health,

particularly among the elderly. Better health, in turn, has led to greater economic

development and more people surviving to old age. Together with decreasing fertility, this

has contributed to ‘population ageing’.

There is increasing analysis being undertaken in relation to the long-term sustainability of

public finances in the context of these widespread demographic trends across the developed

world. Under the Charter of Budget Honesty Act 1998, the Australian Government is

required to prepare an Intergenerational Report (IGR) that assesses the long-term

sustainability of current Government policies over the next 40 years, and to take account of

the financial implications of demographic change. The first IGR was released on 14 May 2002

as part of the 2002–03 Federal Budget (Budget Paper No. 5) and considered future health care

costs based on expected demographic trends and projected Australian Government

expenditure on health services, represented as a proportion of gross domestic product

(GDP), for the period 2002 to 2041.

Likely trends in disease occurrence were not explicitly accounted for in the IGR as the

analytical projections were based on historical trends in major health expenditure program

31

groupings (medical benefits, pharmaceutical benefits and hospitals) at selected ages. It is

optimistic to assume that simply because underlying changes in disease occurrence were

embedded within the historical data on expenditure that they are therefore plausibly

reflected in these analyses. An analysis that explicitly takes account of changes in both

disease occurrence and per unit expenditure at the level of individual diseases is likely to

provide much firmer ground upon which to base estimates of future health expenditure.

Common to both approaches, of course, is the assumption that the rate of change in policy

responses to emerging problems in the future is consistent with the rate observed in the

historical period upon which the projections are based (that is, ‘business as usual’). If these

dynamics change, expectations with regard to the future will consequently change.

One objective of the present study was to address the need for comprehensive health

projections in Australia by analysing the most likely changes in burden of disease and injury

to the year 2023. The past is a good (but far from perfect) predictor of the future and an

important by-product of such work is a comprehensive analysis of past trends in disease

occurrence. To pre-empt the inevitable requests for information on the past, this part of the

study was extended to include ‘back-casting’ of disease burden as well. This has the logical

appeal of ensuring consistency between estimates of past, present and future disease burden.

More importantly, it may limit the potential for misinterpretation should people compare

these current and future burden estimates with results based on alternative methods. The

inevitable comparison that people will make between the results presented in this report and

those of the previous Australian Burden of Disease and Injury Study should be regarded in

this light.

Australia has an excellent vital registration system by international standards and, with few

exceptions (for example pneumonia), observable trends in vital events over time are

arguably the most reliable and consistently recorded information on changes in the

frequency of diseases and injuries that result in death. Previous work (Barendregt et al. 2003)

has shown that the complete epidemiology of a disease is ultimately a function of only three

parameters: incidence (the hazard of getting the disease), remission (the ‘hazard’ of being

cured from having the disease) and case-fatality (the hazard of dying as a consequence of

having the disease). For most chronic diseases, cause-specific mortality is influenced by only

two of these—incidence and case-fatality—with remission having little if any role. It follows,

therefore, that any epidemiological parameter of interest for a chronic disease can be

‘back-cast’ from a point in time for which the complete epidemiology of that disease is

known simply by making assumptions about the relative contribution of incidence and casefatality

to the observed changes in mortality.

This idea also applies to projections, providing one is willing to make predictions about

cause-specific mortality into the future. Since it has already been argued that cause-specific

mortality is a reliable and consistently recorded source of information on changes in disease

frequency in many cases, cause-specific mortality is a sound starting point for projecting the

epidemiology of a disease. Other approaches that are based on predicting incidence from

risk factors may have more intuitive appeal but are more tenuous as they involve multiple

assumptions about disease–exposure relationships and future exposure trajectories.

The methods used in this study involved a number of separate analytical or computational

steps. A brief outline of the overall approach is presented below. More complete details are

provided in subsequent sections of the report as indicated.

1. Baseline models for over 170 diseases and injuries for Australia in 2003 were developed

as part of the core set of analyses for the present study. Appendix 1 discusses each of

these models in detail.

32

2. Trends in observed cause-specific mortality over the period 1979 to 2003 were analysed

and projected into the future using a combination of regression techniques.

3. For mostly fatal conditions, each baseline disease model was extrapolated backwards and

forwards in time based on assumptions about the relative contribution of incidence and

case-fatality to changes in mortality. Baseline models for mostly non-fatal conditions

were extrapolated based on assumptions about changes in incidence only. The complete

epidemiology of each was then estimated separately in a fully dynamic model that

accounted for changes in all-cause mortality as well as changes in incidence and

case-fatality (where appropriate) so that incidence, prevalence and duration by age, sex

and cause was described over the past as well as into the future.

4. Absolute numbers of incident and prevalent cases were derived by applying the rates

from the above analyses to the ABS ‘Series 8’ projection series population estimates (ABS

2003d). This series assumes a high net overseas migration of 125,000 annually, constant

improvements in life expectancy (low mortality assumption), and a total fertility rate

declining to 1.6 by 2011 and then remaining constant.

Incident and prevalent YLD for each disease were calculated for non-baseline periods by

applying durations and extrapolated numbers of incident and prevalent cases from the

dynamic model to disability weights that were corrected for probabilities of comorbidity in

2003. Years of life lost (YLL) for non-baseline periods were calculated directly from observed

deaths in the past and projected deaths into the future.

Mortality trends and projections

Observed all-cause mortality rates for the period 1979 to 2003 were extrapolated into the

future using simple log-linear Poisson regression. Cause-specific mortality data for the same

period were then collapsed into 51 clinically meaningful conditions, or groups of conditions.

Multinomial logistic regression was used to model changes in the contribution of each group

as a proportion of all-cause mortality, with changes in absolute levels of all-cause mortality

expressed as the natural log of the rate per unit of population. These models were used to

predict the future cause-specific structure of mortality based on projected all-cause mortality

rates. Separate analyses were done for each age group and sex.

Among the causes analysed, cardiovascular disease, cancers, chronic obstructive pulmonary

disease (COPD), diabetes, alcohol-related conditions, road traffic accidents, falls, suicide and

homicide showed significant mortality trends. The apparent trend in dementia mortality was

ignored because: (a) there has been a shift in coding practices with more deaths being

attributed to dementia; (b) the prevalence data from international epidemiological studies

showed no clear change over time; (c) the case-fatality was unlikely to have changed much

over time as there are no effective life-saving interventions.

Incidence and case-fatality

Mortality trends for cancers, COPD, diabetes, alcohol-related conditions, road traffic

accidents, falls, suicide and homicide were assumed to be fully due to changes in incidence.

Incidence trends for these causes were therefore adjusted to reflect changes in mortality over

the projection period, with case-fatality being held constant. Findings from Unal et al. (2004)

suggest that 58% of the drop in cardiovascular mortality observed in England and Wales was

due to a drop in incidence and the remaining 42% due to a reduction in case-fatality. The

33

same proportions were assumed to apply in this study to all cardiovascular disease over the

projection period.

Changes in the diagnostic criteria for Type 2 diabetes in surveys and a paucity of

representative survey data meant that there was no direct measurement of trends of Type 2

diabetes in Australia from which to project the incidence of this disease. Body mass index

(BMI, defined as body weight in kilograms divided by the square of height in metres),

overwhelmingly the main risk factor for Type 2 diabetes, however, has been measured

consistently at various points over recent time. The approach taken in this study, therefore,

was to translate historical trends in BMI into expected changes in diabetes incidence

following the risk attribution methods described in the WHO Comparative Risk Assessment

project.

Haby and colleagues (2006) analysed trends in BMI using data from five measurement

surveys: the three National Heart Foundation Risk Factor Prevalence studies in the 1980s, the

National Nutrition Survey of 1995 and the AusDiab study in 1999 and 2000. Projected mean

BMI by age group and sex was derived from Haby and colleagues’ regression model of the

mean of log-transformed BMI values on age, birth cohort and sex. Similar techniques were

applied to the standard deviations of BMI values so as to fully describe the expected change

in the distribution of this risk into the future (a change which can be characterised as a

broadening of the distribution in the tail towards the highest BMI values rather than at the

other end of the distribution with low values).

The population-level risk of diabetes is simply the area under the curve represented by the

distribution of BMI multiplied by the relevant relative risk of developing diabetes at each

level of BMI. This is easiest to derive using integration techniques. Proportional changes in

the size of this area over time represent changes in the incidence of diabetes resulting from

changes in BMI. Ni Mhurchu and colleagues (2006) undertook a meta-analysis of results

from the Asia-Pacific Cohort Study collaboration and report the relative risk of developing

diabetes for each unit increase in BMI by age and sex. Using these relative risks and the

predicted BMI distributions derived above, changes in the incidence of diabetes were

estimated over the projection period. For consistency with CRA methods, a theoretical

minimum distribution of BMI (mean of 21 and standard deviation of 1) was incorporated

into the calculations, below which no excess risk of diabetes was assumed.

Information on trends in case-fatality rates amongst people with diabetes is scarce. In the

absence of such information, an assumption was made that at least half the mortality in these

people is due to vascular causes and is subject to the same factors that influence

cardiovascular disease mortality more generally. Changes in case-fatality for diabetes,

therefore, were assumed to reflect half the trends in case-fatality for cardiovascular disease,

which were estimated to be decreasing over the projection period. The combined effect of

increasing BMI and decreasing case-fatality was a considerable increase in the incidence of

Type 2 diabetes, and an even greater increase in future prevalence.

Non-fatal conditions

Mortality trend data are not relevant for conditions that are largely non-fatal. These include

mental, sense organ and musculoskeletal disorders. The only mental health survey in

Australia was carried out in 1997 and hence there are no trend data. Internationally there is

no clear evidence of trends due to a paucity of mental health survey data collected using

comparable diagnostic tools and criteria. Therefore no trends were assumed. Similarly, no

34

disease trends were applied to hearing loss (only one community survey), and the various

causes of vision loss and musculoskeletal disorders (no evidence for trends).

2.6 Differentials in burden

The high demand for information on health differentials, both between and within

populations, is one measure of the obvious public policy implications of such information.

For example, knowing that the gap in life expectancy at birth between Aboriginal and Torres

Strait Islander Australians and other Australians is demonstrably very large is a sound basis

for new initiatives to improve Indigenous health. One of the aims of the original study was

to develop estimates of disease burden for different groups within the Australian

population. To this end, the final report presented preliminary analyses of inequalities in

disease burden by level of socioeconomic disadvantage, although it was not possible to

complete a comprehensive analysis of non-fatal burden within the time available. An

objective of the current project was to extend these analyses by providing a more complete

picture of disease burden for a much greater range of subgroups within the Australian

population.

The methods used in this study build on the first comprehensive attempt to describe ‘small

area’ variability in health status across Victoria (DHS 2006), and are in the methodological

tradition of describing differences in health across population subgroups. Murray and

colleagues (1999a) differentiate this from descriptions of ‘health inequalities’, a term they

reserve for analysis of the variation in health status across individuals in a population

(analogous to analyses of income inequality, which measure the distribution of income at the

level of individuals). While health inequalities are sometimes regarded as synonymous with

subgroup differences in health in the literature, analyses of the latter are based on subgroup

averages and as such can mask the true extent of inequalities between individuals.

Categorising geographic areas

The most disaggregated geographic information on place of usual residence for most

Australian health data is the Statistical Local Area (SLA), and this geographic entity is used

as the unit of analysis for this component of the study. For various reasons, SLA names and

boundaries are revised over time, the most substantial revision occurring as a result of local

government amalgamations in the early 1990s. To achieve geographic consistency, all data,

regardless of year, were analysed in terms of ASGC definitions for the year 2001 (ASGC, or

Australian Standard Geographical Classification, being the reference used to define SLAs)

(ABS 2001a). Data defined in terms of SLAs fragmented as a result of boundary revisions

were reapportioned using information from the 2001 Census on the proportion of each old

SLA population residing in each current SLA after the redrawing of the boundaries. Irregular

coding in data arising from such revisions was resolved on a case-by-case basis using historic

documentation provided by the ABS. Estimated mid-year resident population figures for

each SLA by year (1999 to 2003), 5-year age groups (0, 5…85+) and sex were obtained from

the ABS.

The ASGC 2001 provides for the classification of SLAs in terms of both socioeconomic status

and remoteness. Socioeconomic status can be determined from one of four socioeconomic

indexes for areas (SEIFA indexes) developed by the ABS from the 2001 Census using

principal component methods on attributes such as low income, low educational attainment,

35

high levels of public sector housing, high unemployment, and jobs in relatively unskilled

occupations (ABS 2001b). This study uses the index of disadvantage that is functionally

equivalent to the Index of Relative Socioeconomic Disadvantage derived from the 1996

Census. This index is estimated at a collector-district level to be normally distributed at a

national level, and can be population-weighted to derive values for ASGC 2001 SLAs.

Socioeconomic quintiles were derived by ranking SLAs in order of disadvantage index then

grouping them into five categories such that each category contains approximately 20% of

the total Australian population.

Remoteness can be determined from the Accessibility/Remoteness Index of Australia

(ARIA+) developed by the Australian Government Department of Heath and Ageing and

the National Centre for Social Applications of Geographic Information Systems (GISCA), and

subsequently incorporated into ASGC 2001 (ABS 2001a). ARIA+ is a continuous varying

index with values ranging from 0 (high accessibility) to 15 (high remoteness), and is based on

road distance measurements from 11,879 populated localities to the nearest service centre.

Index values for each locality have been interpolated to a 1 km grid so that all areas of

Australia have an index value and scores for larger areas such as SLAs can be derived. Each

SLA was classified into one of three groups based on the following standard cut-points as

defined in ASGC 2001: Major cities (0–0.20), Regional (>0.20–5.92) and Remote (>5.92).

Estimating burden for subpopulations

One category of information readily available for disaggregating national estimates of

burden to subpopulations is data on observed variations in event frequency for any

aggregation from the level of the SLA and above. This includes the National Mortality

dataset, the National Hospital Morbidity Database and the National Cancer Statistics

Clearing House dataset. The other category comprises information that can be tabulated by

state or territory jurisdiction, disadvantage quintile or remoteness category, but cannot be

disaggregated below these strata. Most surveys (for example the National Health Survey, the

Survey on Disability, Ageing and Carers, the National Survey of Mental Health and

Wellbeing, and the Australian Diabetes Obesity and Lifestyle Study (AusDiab)) and

published data tabulations fit this description. The primary objective with either category

was to derive relativities between whatever level of disaggregation was possible, and to

ensure that these relativities were as accurate as possible and not simply an artefact of small

numbers. Of less concern was the absolute level of disease occurrence being reported,

because these would be constrained by national estimates.

The adopted strategy was intended to ensure consistency in the use of the available

information and to ensure sufficient numbers at each level of the analysis. First, all sources

were assessed for whether they could provide simple state/territory jurisdiction proportions

(preferably by sex, but not necessarily by age) for any condition in the study’s list of diseases

and injuries. Most sources could provide this information. Next, they were assessed for

plausibility as a valid proxy for variability in disease occurrence across a 15-cell matrix

comprising five SEIFA categories and three remoteness categories. Not as many sources

could provide this information and, of these, a few could provide information on only one

dimension (that is, either SEIFA or remoteness, but not both). Age-standardised rates were

then calculated for each cell of observed data, and these were divided by the crude rate for

the whole matrix to derive 15 cell-specific standardised rate ratios. In matrices with only one

dimension, ratios for the observed dimension were held constant across the missing

dimension.

36

This estimation process means that the estimates of deaths of cancer cases in a particular SLA

are not the same as the actual deaths or cancer cases in that SLA, but are synthetic estimates

which reflect the rates of deaths and cancer in SLAs of similar type.

Having determined possible sources for two pieces of information (state/territory

proportions and matrices of rate ratios), an assessment was made for each disease and injury

category as to whether there was agreement between sources (if there were more than one)

and which information seemed sufficiently robust in terms of underlying numbers. For

conditions with a predominantly fatal burden, preference was given to information derived

from mortality data. For other conditions, preference was given to the data source upon

which the national disability model was based.

Each condition was then assigned a single source to be used to derive the proportion of

national incidence cases that would be expected to occur in each state and territory. If no

source could be identified, the number of incident cases was unconstrained at this step in the

disaggregation. The implied jurisdiction-specific rate (or national rate where jurisdiction

numbers were unconstrained) was then distributed to subpopulations within the jurisdiction

using one of the matrices of rate ratios derived in the previous step. If no matrix was

available, rates were held constant across subpopulations within jurisdictions. Derived

incident cases were then rescaled to be consistent with jurisdiction totals where applicable,

and ultimately national totals. Deaths were treated in the same way as incident cases.

The final step was to derive prevalent cases and duration for each condition and its sequelae

for each subpopulation within jurisdictions. An automated implementation of the equations

underlying DisMod (an epidemiological modelling software package) was applied to

subpopulation-specific incidence rates and national assumptions regarding remission and

case-fatality to derive these parameters. In order to derive accurate durations, one of 15 sets

of all-cause mortality rates was used according to the SEIFA and remoteness category of the

subpopulation. All subpopulation-specific prevalent cases and YLD (both incident and

prevalent) were then rescaled to be consistent with national totals.

Subpopulation comparisons in this report

This report is limited to the following subpopulation comparisons:

1. state and territory jurisdictions

2. remoteness categories

3. socioeconomic quintiles.

While the analyses were aimed at disaggregating national burden estimates to the level of

the SLA, there was no intention to disseminate results at this level of detail. In addition to the

potential privacy considerations of the data providers, the release of such information may

be misleading given the methods used. Rather, the authors and various jurisdictional

stakeholders are working to regroup the data into meaningful aggregations of SLAs for

specific health policy and planning purposes.

37

3 Burden of disease and injury in

Australia

This chapter discusses the burden of disease and injury in Australia in 2003 by fatal and nonfatal

burden, sex, age and leading broad cause group. The numbers presented in this chapter

should not be compared with those presented in the previous report (AIHW: Mathers et al.

1999) due to substantially different methods for many of the disability models. Readers who

are interested in gaining an understanding of changes in burden over time are referred to

Chapter 6 which discusses trends in population health over a 30-year period.

3.1 Disability-adjusted life years

Cancer, cardiovascular disease and mental disorders were the leading causes of total burden

of disease and injury in Australia in 2003 (Figure 3.1). Cancer and cardiovascular disease

accounted for 37% of the total burden; for both causes, four-fifths of this burden was from

mortality. Mental disorders and neurological & sense disorders were the next largest

contributors, together accounting for a further quarter of the total burden. The contribution

of mortality to the burden from these two groups was small, highlighting the importance of

including non-fatal health outcomes in population health measurement.

Overall, half the total burden (49%) was due to mortality and the distribution between the

sexes was roughly equal for most causes, with injuries (70% of the burden in males) and

musculoskeletal disorders (58% of the burden in females) the exceptions.

Cancer

Cardiovascular

Neuro- Mental

logical

Chronic

respiratory

Injuries

Diabetes

Musculoskeletal

Other

19%

18%

12% 13%

7%

7%

5%

4%

14%

Total

Injuries

Diabetes

Cardiovascular

Chronic respiratory

Cancer

Mental

Neurological

Musculoskeletal

52%

70%

54%

53%

53%

53%

47%

47%

42%

48%

30%

46%

47%

47%

47%

53%

53%

58%

Males Females

Total

Cancer

Cardiovascular

Injuries

Chronic respiratory

Diabetes

Neurological

Musculoskeletal

Mental

49%

82%

78%

76%

38%

22%

17%

7%

7%

51%

18%

22%

24%

62%

78%

83%

93%

93%

Fatal Non-fatal

Figure 3.1: Burden (DALYs) by broad cause group expressed as: (a) proportions of total,

(b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes, Australia,

2003

38

Total burden in absolute terms increased at a relatively constant rate until age 75 (Figure

3.2b), while the burden per head of population continued to rise exponentially, with small

but significant peaks in childhood and early adulthood (Figure 3.2a). Injuries in males and

mental disorders were the main cause groups until middle age and accounted for the

majority of total burden in early adulthood, after which cancer, cardiovascular disease and

neurological & sense disorders were more prominent. The contribution from cancer peaked

at age 70 then declined, leaving cardiovascular disease as the major cause of burden in the

elderly (Figure 3.2b).

0

500

1,000

Rate 1,000

0 20 40 60 80 100

Age

Males

Females

0

100

200

300

(thousands)

0 20 40 60 80 100

Age

Other

Musculoskeletal

Diabetes

Injuries

Chronic respiratory

Neurological

Mental

Cardiovascular

Cancer

Figure 3.2: Burden (DALYs) by age expressed as: (a) rates by sex, and (b) numbers by broad cause

group, Australia, 2003

The burden due to specific disease and injury categories reflected the more general picture at

the broad cause group level. Ischaemic heart disease was the largest single cause in males,

accounting for 11.1% of the total male burden (Table 3.1). For females, anxiety & depression

was the leading cause, accounting for 10.0% of the total female burden. Ischaemic heart

disease, stroke, Type 2 diabetes and dementia were the next four leading causes of DALYs in

females. In males, Type 2 diabetes, anxiety & depression, lung cancer and stroke were the

next four leading causes.

Seven health areas have been identified by the Commonwealth, state and territory

governments for priority attention as National Health Priority Areas: asthma, cancer,

cardiovascular disease, diabetes mellitus, injuries, mental health, and arthritis and

musculoskeletal conditions. In addition, dementia is an Australian Government health

priority. In 2003, these eight health groupings accounted for 72.8% of the total burden, 17 of

the 20 leading conditions for males and 15 of the 20 leading conditions for females.

per Number

39

Table 3.1: Leading causes of burden (DALYs) by sex, Australia, 2003

Rank Males DALYs

Per

cent of

total Females DALYs

Per cent

of total

1 Ischaemic heart disease 151,107 11.1 Anxiety & depression 126,464 10.0

2 Type 2 diabetes 71,176 5.2 Ischaemic heart disease 112,390 8.9

3 Anxiety & depression 65,321 4.8 Stroke 65,166 5.1

4 Lung cancer 55,028 4.0 Type 2 diabetes 61,763 4.9

5 Stroke 53,296 3.9 Dementia 60,747 4.8

6 COPD 49,201 3.6 Breast cancer 60,520 4.8

7 Adult-onset hearing loss 42,653 3.1 COPD 37,550 3.0

8 Suicide & self-inflicted injuries 38,717 2.8 Lung cancer 33,876 2.7

9 Prostate cancer 36,547 2.7 Asthma 33,828 2.7

10 Colorectal cancer 34,643 2.5 Colorectal cancer 28,962 2.3

11 Dementia 33,653 2.5 Adult-onset hearing loss 22,200 1.8

12 Road traffic accidents 31,028 2.3 Osteoarthritis 20,083 1.6

13 Asthma 29,271 2.1 Personality disorders 16,339 1.3

14 Alcohol abuse 27,225 2.0 Migraine 15,875 1.3

15 Personality disorders 16,248 1.2 Back pain 15,188 1.2

16 Schizophrenia 14,785 1.1 Lower respiratory tract infections 14,233 1.1

17 Osteoarthritis 14,495 1.1 Falls 13,269 1.0

18 Back pain 14,470 1.1 Parkinson’s disease 13,189 1.0

19 Melanoma 13,734 1.0 Schizophrenia 12,717 1.0

20 Parkinson’s disease 13,664 1.0 Rheumatoid arthritis 12,062 1.0

Table 3.2 compares burden by broad cause groups in 2003 with total health system

expenditures in 2000–01. This table is included to illustrate a misunderstanding about the

relationship between health expenditure and health outcomes. It is sometimes argued, for

example, that the proportion of total expenditure that is committed to a particular health

problem should be commensurate in some way to its contribution to total burden. This is not

necessarily the case.

Burden estimates describe the health problems that remain in a population in spite of all

currently implemented prevention and treatment strategies. Large expenditure for a cause

with a small burden is money well spent if that expenditure reflects an efficient health

service response to what otherwise would have been a much larger problem. Oral

conditions, for example, account for only 0.9% of total burden but consume 6.7% of total

expenditure ($3.4 billion). This commitment of resources may well represent a good

investment if it keeps the burden from oral conditions at low levels and that without it, the

burden would be much higher. If, on the other hand, some of this expenditure is not

impacting on the burden, because it is being directed towards cosmetic or ineffective

services, for example, or there are inefficiencies in the delivery of oral health services, then

the conclusion may be less sanguine.

The real test of whether an investment has been worthwhile depends on the change in

burden resulting from the expenditure as well as the opportunity cost of that expenditure to

investments in other areas of the health sector. Exploring this requires information on the

40

effectiveness and costs associated with all current prevention and treatment strategies. Such

analyses are beyond the scope of this report.

The proportion of burden for a particular health problem vis-a-vis expenditure, therefore, is

more appropriately used as one argument amongst others for prioritising research into the

development of new treatment and preventive interventions, and into assessing the

effectiveness of these interventions. It should not be used to prioritise existing treatment and

preventive activities.

Table 3.2: Burden (DALYs) in 2003 and expenditure in 2000–01 by broad cause group, Australia

DALYs in 2003 Expenditure in 2000–01(a)

Cause No. (thousands) Per cent $ (millions) Per cent

Neoplasms(b) 510.3 19.4 2,918 5.8

Cardiovascular disease 473.8 18.0 5,479 10.9

Mental disorders 350.5 13.3 3,741 7.5

Neurological & sense disorders 312.8 11.9 4,942 9.9

Respiratory disease(c) 222.2 8.4 3,742 7.5

Injuries 185.1 7.0 4,013 8.0

Diabetes mellitus 143.8 5.5 812 1.6

Musculoskeletal diseases 105.5 4.0 4,634 9.2

Genitourinary diseases 65.2 2.5 2,076 4.1

Diseases of the digestive system 58.0 2.2 2,811 5.6

Infectious & parasitic diseases 44.7 1.7 1,224 2.4

Neonatal causes 34.6 1.3 358 0.7

Congenital anomalies 33.2 1.3 221 0.4

Endocrine & metabolic disorders 28.6 1.1 1,587 3.2

Oral conditions 24.5 0.9 3,372 6.7

Skin diseases 20.3 0.8 1,370 2.7

Maternal conditions 2.2 0.1 1,315 2.6

Other(d) 17.5 0.7 5,530 11.0

All causes 2,632.8 100.0 50,146 100.0

(a) Total health system expenditures from AIHW 2005c.

(b) Includes cancers (malignant neoplasms) and other (non-malignant) neoplasms.

(c) Includes chronic respiratory disease and acute respiratory infections.

(d) Includes ‘Signs, symptoms and ill-defined conditions’ which includes expenditure on diagnostic and other services for signs, symptoms and

ill-defined conditions where the cause of the problem is unknown and includes ‘other contact with the health system’ such as fertility control,

reproduction and development, elective plastic surgery, general prevention, screening and health examination; and treatment and aftercare

for unspecified disease.

3.2 Years of life lost

Years of life lost (YLL), or fatal burden, accounted for 49% of the total burden of disease and

injury in Australia in 2003 (Figure 3.1c). Cancers, cardiovascular disease and injuries were

responsible for almost three-quarters of this burden (Figure 3.3a). Since the 1996 study,

cancer has overtaken cardiovascular disease as the greatest cause of fatal burden as

41

cardiovascular mortality has declined much more than cancer mortality over the past three

to four decades. Males experienced 55% of the total fatal burden.

Cancer

Cardiovascular

Injuries

Chronic

respiratory

Neurological

Diabetes

Other

32%

29%

11%

6%

4%

3%

16%

Total

Injuries

Diabetes

Chronic respiratory

Cardiovascular

Cancer

Neurological

55%

72%

56%

54%

54%

53%

45%

45%

28%

44%

46%

46%

47%

55%

Males Females

Figure 3.3: Fatal burden (YLL) expressed as: (a) proportion by broad cause group, and

(b) proportion by sex for each broad cause group, Australia, 2003

As with total burden, fatal burden increased in absolute terms at a relatively constant rate

until age 75 (Figure 3.4b), while the burden per head of population continued to increase

exponentially, with small but important peaks in childhood and, in males, early adulthood

(Figure 3.4a). Injury was the main cause of fatal burden until age 35 and accounted for the

majority of fatal burden in early life, after which cancer and cardiovascular disease were

more prominent. The contribution from cancer peaked at age 70 then declined, leaving

cardiovascular disease as the major cause of fatal burden in the elderly (Figure 3.4b).

42

0

200

400

600

0 20 40 60 80 100

Age

Males

Females

0

50

100

150

Number (0 20 40 60 80 100

Age

Other

Chronic respiratory

Injuries

Cardiovascular

Cancer

Figure 3.4: Fatal burden (YLL) by age expressed as: (a) rates by sex, and (b) numbers by broad

cause group, Australia, 2003

Again, the fatal burden due to specific disease and injury categories reflected the more

general picture at the broad cause group level. Ischaemic heart disease was the disease

contributing most to YLL in both males and females. Stroke was the second largest disease

causing YLL in females, followed by breast cancer and lung cancer. In males, lung cancer

ranked second, followed by suicide & self-inflicted injuries, stroke, and colorectal cancer

(Table 3.3).

Rate per 1,000

thousands)

43

Table 3.3: Leading causes of mortality burden (YLL) by sex, Australia, 2003

Rank Males YLL

Per cent

of total Females YLL

Per cent

of total

1 Ischaemic heart disease 128,991 18.2 Ischaemic heart disease 89,152 15.7

2 Lung cancer 51,505 7.3 Stroke 48,548 8.5

3 Suicide & self-inflicted injuries 38,434 5.4 Breast cancer 40,080 7.0

4 Stroke 36,152 5.1 Lung cancer 31,551 5.5

5 Colorectal cancer 27,997 3.9 Colorectal cancer 23,735 4.2

6 Road traffic accidents 26,674 3.8 COPD 21,025 3.7

7 COPD 26,183 3.7 Dementia 16,009 2.8

8 Prostate cancer 23,175 3.3 Lower respiratory tract infections 12,309 2.2

9 Type 2 diabetes 15,273 2.2 Type 2 diabetes 11,751 2.1

10 Hepatitis 12,524 1.8 Pancreas cancer 10,984 1.9

11 Alcohol abuse 11,449 1.6 Ovary cancer 10,946 1.9

12 Lower respiratory tract infections 11,221 1.6 Suicide & self-inflicted injuries 10,945 1.9

13 Pancreas cancer 11,136 1.6 Road traffic accidents 9,678 1.7

14 Brain cancer 10,718 1.5 Nephritis & nephrosis 9,521 1.7

15 Lymphoma 10,474 1.5 Lymphoma 8,324 1.5

16 Melanoma 10,108 1.4 Brain cancer 7,809 1.4

17 Leukaemia 10,039 1.4 Leukaemia 7,468 1.3

18 Oesophagus cancer 9,427 1.3 Hepatitis 6,534 1.1

19 Nephritis & nephrosis 9,336 1.3 Falls 5,845 1.0

20 Stomach cancer 8,209 1.2 Stomach cancer 5,609 1.0

3.3 Years lost due to disability

Years lost due to disability (YLD), or non-fatal burden, are typically calculated from

incidence cases in a base year and as such are to be interpreted as the number of healthy

years lost due to disability that will accrue into the future from new cases of disease and

injury in that base year. Incident non-fatal burden is added to fatal burden (YLL) to derive

total burden (DALYs). An alternative way of calculating non-fatal burden uses prevalent

cases as the basis. Prevalent non-fatal burden (PYLD) is to be interpreted as the number of

healthy years lost due to disability currently experienced by a population. This cannot be

added to fatal burden to derive total burden in the same way as incident non-fatal burden.

Both methods of calculating non-fatal burden are presented below. For all the other sections

of this report, references to non-fatal burden reflect incident non-fatal burden unless

otherwise specified.

Incident YLD

Incident non-fatal burden accounted for 51% of the total burden of disease and injury in

Australia in 2003 (Figure 3.1c). Mental, neurological and sense disorders contributed most,

44

together accounting for 43% of this burden (Figure 3.5a). While cancer, cardiovascular

disease and injuries contributed 72% to the total fatal burden (Figure 3.3a), these causes did

not make a similar contribution to incident non-fatal burden. Incident non-fatal burden was

distributed equally between the sexes (Figure 3.5b).

Mental

Neurological

Chronic

respiratory

Diabetes

Cardiovascular

Musculoskeletal

Other

24%

19%

8% 9%

8%

7%

25%

Total

Diabetes

Chronic respiratory

Cardiovascular

Neurological

Mental

Musculoskeletal

48%

53%

52%

51%

47%

45%

42%

52%

47%

48%

49%

53%

55%

58%

Males Females

Figure 3.5: Non-fatal burden (YLD) expressed as: (a) proportion by broad cause group, and

(b) proportion by sex for each broad cause group, Australia, 2003

Incident non-fatal burden increased rapidly in absolute terms until early adulthood then

levelled out, while the rate per head of population continued increasing, but at a slower rate

than for fatal burden (Figure 3.6). Mental disorders were the main causes of incident nonfatal

burden until middle age and accounted for the majority of fatal burden in early life,

after which neurological & sense disorders were more prominent, accounting for the

majority of non-fatal burden in the elderly. Chronic respiratory conditions accounted for a

small but consistent proportion of incident non-fatal burden, with peaks in childhood due to

asthma and at older ages from chronic obstructive pulmonary disease (Figure 3.6).

45

Figure 3.6: Incident non-fatal burden (YLD) by age expressed as: (a) rates by sex, and (b) numbers

by broad cause group, Australia, 2003

Anxiety & depression and Type 2 diabetes were the leading causes of incident non-fatal

burden in males and females (Table 3.4). Dementia was the third leading cause in females,

followed by asthma and ischaemic heart disease. In males, adult-onset hearing loss ranked

third, followed by asthma. Mental disorders accounted for six of the 20 leading causes of

incident non-fatal burden in males and three in females.

0

100

200

Rate per 1,000

0 20 40 60 80 100

Age

Males

Females

0

50

100

150

Number (thousands)

0 20 40 60 80 100

Age

Other

Diabetes

Chronic respiratory

Neurological

Mental

46

Table 3.4: Leading causes of incident non-fatal burden (YLD) by sex, Australia, 2003

Rank Males YLD

Per cent

of total Females YLD

Per cent

of total

1 Anxiety & depression 65,208 10.0 Anxiety & depression 126,244 18.1

2 Type 2 diabetes 55,903 8.5 Type 2 diabetes 50,012 7.2

3 Adult-onset hearing loss 42,653 6.5 Dementia 44,738 6.4

4 Asthma 27,649 4.2 Asthma 31,405 4.5

5 Dementia 25,558 3.9 Ischaemic heart disease 23,238 3.3

6 COPD 23,018 3.5 Adult-onset hearing loss 22,200 3.2

7 Ischaemic heart disease 22,116 3.4 Breast cancer 20,440 2.9

8 Stroke 17,144 2.6 Osteoarthritis 19,775 2.8

9 Personality disorders 16,248 2.5 Stroke 16,619 2.4

10 Alcohol abuse 15,775 2.4 COPD 16,525 2.4

11 Schizophrenia 14,673 2.2 Personality disorders 16,339 2.3

12 Osteoarthritis 14,429 2.2 Migraine 15,868 2.3

13 Back pain 14,355 2.2 Back pain 15,129 2.2

14 Prostate cancer 13,372 2.0 Schizophrenia 12,577 1.8

15 Autism spectrum disorders 11,702 1.8 Rheumatoid arthritis 10,918 1.6

16 Parkinson’s disease 10,623 1.6 Parkinson’s disease 10,534 1.5

17 Refractive errors 8,241 1.3 Refractive errors 10,520 1.5

18 Peripheral vascular disease 7,965 1.2 Infertility 8,076 1.2

19 Heroin or polydrug abuse 7,498 1.1 Falls 7,424 1.1

20 Benign prostatic hypertrophy 7,378 1.1 Macular degeneration 7,259 1.0

Prevalent YLD

Figure 3.7 illustrates the prevalent non-fatal burden by age. The difference between

prevalent and incident non-fatal burden is most apparent for childhood conditions, such as

asthma and congenital disorders, and for chronic mental disorders, the incidence of which

peaks in childhood and early adulthood. Incident non-fatal burden at these life stages is

much larger compared to prevalent non-fatal burden because most incident cases of chronic

conditions at young ages are expected to remain prevalent cases at older ages. This explains

the shift to the right in the picture of prevalent non-fatal burden (Figure 3.7) compared to

incident non-fatal burden (Figure 3.6).

The rate of prevalent burden was lowest in children between 1 and 4 years of age (15 PYLD

per thousand) and increased to 147 in people aged 65 to 69 years and then to 415 per

thousand in people over the age of 95. In other words, disability from all diseases and

injuries resulted in a loss of 1.5% of healthy time lived by young children, increasing with

age to 14.7% in those 65 to 69 years and 41.5% in the very old.

47

Figure 3.7: Prevalent non-fatal burden (PYLD) by age expressed as: (a) rates by sex, and

(b) numbers by broad cause group, Australia, 2003

3.4 Age and sex patterns

In this section, the size and composition of burden is reported by five broad age groups

(Table 3.5).

Table 3.5: Distribution of population and burden (DALYs) by five broad age groups, Australia,

2003

Age group Population (a)

Per cent

of total DALYs

Per cent

of total

0–14 years 3,979,410 20.0 221,536 8.4

15–44 years 8,622,610 43.4 633,260 24.1

45–64 years 4,733,808 23.8 681,566 25.9

65–74 years 1,349,949 6.8 428,904 16.3

75 years and over 1,195,692 6.0 667,504 25.4

Total 19,881,469 100.0 2,632,770 100.0

(a) Estimated resident population figures as at 30 June 2003 (ABS cat. no. 3201.0).

Children aged 0–14 years

Children aged 0–14 years comprised 20.0% of the total population and experienced 8.4% of

the total burden of disease and injury in Australia in 2003 (Table 3.5). Twenty-three per cent

of this burden was due to mental disorders (that is anxiety & depression, attention-deficit

hyperactivity disorder and autism spectrum disorders), 18% due to chronic respiratory

conditions (mostly asthma) and 16% due to neonatal conditions. Less than a quarter of the

0

200

400

Rate per 1,000

0 20 40 60 80 100

Age

Males

Females

0

50

100

150

Number (thousands)

0 20 40 60 80 100

Age

Other

Cardiovascular

Chronic respiratory

Neurological

Mental

48

burden was due to mortality (Figure 3.8). Males experienced 56% of the burden in this age

group.

Mental

Chronic

respiratory

Neonatal

Congenital

Injuries

Neurological

Other

23%

18%

16%

12%

7%

7%

18%

Total

Chronic respiratory

Congenital

Mental

Injuries

Neurological

Neonatal

56%

58%

58%

57%

57%

57%

55%

44%

42%

42%

43%

43%

43%

45%

Males Females

Total

Neonatal

Injuries

Congenital

Neurological

Chronic respiratory

Mental

24%

55%

50%

41%

17%

3%

0%

76%

45%

50%

59%

83%

97%

100%

Fatal Non-fatal

Figure 3.8: Burden (DALYs) in 0–14 year olds by broad cause group expressed as: (a) proportions

of total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes, Australia,

2003

Asthma was the leading cause of burden for both males and females (Table 3.6). This was

followed by autism spectrum disorders, anxiety & depression, and low birth weight in

males. In females, anxiety & depression, low birth weight and birth trauma & asphyxia were

the next leading causes. The leading 10 causes of burden accounted for 58.7% of the total

burden in this age group.

Table 3.6: Leading causes of DALYs in 0–14 year olds by sex, Australia, 2003

Rank Males DALYs

Per cent

of total Females DALYs

Per cent

of total

1 Asthma 21,953 17.6 Asthma 16,490 17.0

2 Autism spectrum disorders 11,703 9.4 Anxiety & depression 15,507 16.0

3 Anxiety & depression 9,554 7.7 Low birth weight 7,142 7.4

4 Low birth weight 8,281 6.6 Birth trauma & asphyxia 4,221 4.4

5

Attention-deficit hyperactivity

disorder 7,082 5.7

Attention-deficit hyperactivity

disorder 2,840 2.9

6 Birth trauma and asphyxia 5,086 4.1 Epilepsy 2,446 2.5

7 Congenital heart disease 3,434 2.8 Congenital heart disease 2,202 2.3

8 Epilepsy 3,249 2.6 Autism spectrum disorders 2,056 2.1

9 Neonatal infections 2,156 1.7 Otitis media 1,377 1.4

10 Road traffic accidents 1,991 1.6 Road traffic accidents 1,336 1.4

49

Older children and adults aged 15–44 years

Older children and adults aged 15–44 years comprised 43.4% of the total population and

experienced 24.1% of the total burden of disease and injury in Australia in 2003 (Table 3.5).

Over a third of the total burden in this age group was attributable to mental disorders, and

another 17% was due to injuries (Figure 3.9). There were considerable sex differences in this

age group, with females experiencing a greater share of the burden from neurological

disorders, chronic respiratory diseases, cancers and mental disorders than males. Males, on

the other hand, experienced more than three-quarters of the injury burden, partly because of

their greater inclination for risk taking. Overall, 29% of the burden in this age group was due

to mortality.

Mental

Cancer Injuries

Neurological

Cardiovascular

Chronic

respiratory

Other

36%

7% 17%

7%

5%

5%

23%

Total

Injuries

Cardiovascular

Mental

Cancer

Chronic respiratory

Neurological

51%

78%

64%

45%

43%

43%

41%

49%

22%

36%

55%

57%

57%

59%

Males Females

Total

Injuries

Cancer

Cardiovascular

Neurological

Chronic respiratory

Mental

29%

80%

77%

63%

16%

10%

4%

71%

20%

23%

37%

84%

90%

96%

Fatal Non-fatal

Figure 3.9: Burden (DALYs) in 15–44 year olds by broad cause group expressed as: (a) proportions

of total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes, Australia,

2003

Anxiety & depression was by far the leading single cause of burden in both males and

females, followed by suicide & self-inflicted injuries and road traffic accidents in males, and

migraine and Type 2 diabetes in females (Table 3.7). Mental disorders made up half of the

top 10 leading causes of burden in males and three of the top 10 leading causes of burden in

females. The leading 10 ranked conditions accounted for 54.8% of the burden in this age

group.

50

Table 3.7: Leading causes of DALYs in 15–44 year olds by sex, Australia, 2003

Rank Males DALYs

Per cent

of total Females DALYs

Per cent

of total

1 Anxiety & depression 42,237 13.0 Anxiety & depression 84,717 27.4

2 Suicide & self-inflicted injuries 27,592 8.5 Migraine 14,105 4.6

3 Road traffic accidents 22,845 7.1 Type 2 diabetes 12,487 4.0

4 Schizophrenia 14,376 4.4 Asthma 11,311 3.7

5 Alcohol abuse 13,953 4.3 Schizophrenia 11,064 3.6

6 Type 2 diabetes 12,868 4.0 Personality disorders 9,389 3.0

7 Heroin abuse 11,882 3.7 Breast cancer 9,068 2.9

8 Personality disorders 10,526 3.2 Infertility 8,057 2.6

9 Ischaemic heart disease 9,750 3.0 Suicide & self-inflicted injuries 7,174 2.3

10 COPD 6,840 2.1 Road traffic accidents 6,751 2.2

Adults aged 45–64 years

Adults aged 45–64 years comprised 23.8% of the total population and experienced 25.9% of

the total burden of disease and injury in Australia in 2003 (Table 3.5). Cancer, cardiovascular

disease and neurological disorders accounted for more than half of the total burden in this

age group. Males experienced a greater share of the burden than females for all causes except

mental disorders and musculoskeletal disorders (Figure 3.10). Overall, 49% of the burden in

this age group was due to mortality.

Cancer

Cardiovascular

Neurological

Mental

Diabetes

Musculoskeletal

Other

28%

16%

10%

9%

8%

6%

21%

Total

Cardiovascular

Diabetes

Neurological

Cancer

Mental

Musculoskeletal

56%

68%

60%

59%

51%

44%

44%

44%

32%

40%

41%

49%

56%

56%

Males Females

Total

Cancer

Cardiovascular

Mental

Diabetes

Neurological

Musculoskeletal

49%

81%

69%

14%

14%

13%

4%

51%

19%

31%

86%

86%

87%

96%

Fatal Non-fatal

Figure 3.10: Burden (DALYs) in 45–64 year olds by broad cause group expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and

non-fatal outcomes, Australia, 2003

51

Ischaemic heart disease was the leading cause of burden in males, followed by Type 2

diabetes and lung cancer (Table 3.8). In females, the top three causes were breast cancer,

anxiety & depression and Type 2 diabetes. The top 10 conditions accounted for 52.0% of total

burden in this age group.

Table 3.8: Leading causes of DALYs in 45–64 year olds by sex, Australia, 2003

Rank Males DALYs

Per cent

of total Females DALYs

Per cent

of total

1 Ischaemic heart disease 47,782 12.5 Breast cancer 32,012 10.7

2 Type 2 diabetes 32,741 8.6 Anxiety & depression 25,744 8.6

3 Lung cancer 20,861 5.5 Type 2 diabetes 22,299 7.5

4 Adult-onset hearing loss 20,847 5.5 Ischaemic heart disease 17,489 5.8

5 COPD 15,389 4.0 Lung cancer 13,475 4.5

6 Colorectal cancer 14,130 3.7 Adult-onset hearing loss 10,576 3.5

7 Stroke 13,800 3.6 COPD 10,422 3.5

8 Anxiety & depression 11,757 3.1 Colorectal cancer 9,808 3.3

9 Alcohol abuse 10,077 2.6 Stroke 9,693 3.2

10 Prostate cancer 8,953 2.3 Back pain 6,620 2.2

Adults aged 65–74 years

Adults aged 65–74 years comprised 6.8% of the total population and experienced 16.3% of

the total burden of disease and injury in Australia in 2003 (Table 3.5). Cancer and

cardiovascular disease accounted for over half of the total burden in this age group (Figure

3.11). Females experienced a greater share of the burden than males from musculoskeletal

conditions, while the reverse was true for all other broad cause groups. Overall, 60% of the

burden in this age group was due to mortality.

52

Total

Cardiovascular

Cancer

Chronic respiratory

Diabetes

Neurological

Musculoskeletal

57%

61%

59%

56%

56%

52%

42%

43%

39%

41%

44%

44%

48%

58%

Males Females

Total

Cancer

Cardiovascular

Chronic respiratory

Diabetes

Neurological

60%

83%

76%

61%

35%

40%

17%

24%

39%

65%

Fatal Non-fatal

Figure 3.11: Burden (DALYs) in 65–74 year olds by broad cause group expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and

non-fatal outcomes, Australia, 2003

Ischaemic heart disease, lung cancer and Type 2 diabetes were the leading causes of burden

in males, together accounting for 29% of total male burden (Table 3.9). In females, ischaemic

heart disease, Type 2 diabetes and breast cancer were the leading causes, accounting for 23%

of total burden. The top 10 conditions accounted for 56.3% of total burden in this age group.

Table 3.9: Leading causes of DALYs in 65–74 year olds by sex, Australia, 2003

Rank Males DALYs

Per cent

of total Females DALYs

Per cent

of total

1 Ischaemic heart disease 37,860 15.5 Ischaemic heart disease 21,052 11.4

2 Lung cancer 19,258 7.9 Type 2 diabetes 11,517 6.2

3 Type 2 diabetes 14,203 5.8 Breast cancer 10,445 5.7

4 Prostate cancer 11,950 4.9 Dementia 10,236 5.5

5 Adult-onset hearing loss 11,920 4.9 Lung cancer 9,937 5.4

6 COPD 11,693 4.8 Stroke 9,635 5.2

7 Stroke 10,938 4.5 COPD 8,855 4.8

8 Colorectal cancer 10,531 4.3 Colorectal cancer 7,513 4.1

9 Dementia 7,872 3.2 Osteoarthritis 6,088 3.3

10 Parkinson’s disease 3,958 1.6 Adult-onset hearing loss 5,834 3.2

Cancer

Cardiovascular

Neurological

Chronic

respiratory

Diabetes

Musculoskeletal

Other

31%

15% 23%

7%

6%

5%

14% Musculoskeletal

13%

9%

87%

91%

53

Older people aged 75 years and over

Older people aged 75 years and over comprised 6.0% of the total population and experienced

25.4% of the total burden of disease and injury in Australia in 2003 (Table 3.5).

Cardiovascular disease and cancer accounted for over half of the total burden in this age

group (Figure 3.12). Females experienced a greater share of the burden than males overall

and for all broad cause groups except chronic respiratory diseases and cancer. Overall, 68%

of the burden in this age group was due to mortality.

Cardiovascular

Cancer

Neurological

Chronic

respiratory

Diabetes

Genitourinary

Other

34%

19%

18%

7%

4% 3%

14% Total

Cancer

Chronic respiratory

Genitourinary

Diabetes

Cardiovascular

Neurological

43%

52%

51%

48%

42%

41%

38%

57%

48%

49%

52%

58%

59%

62%

Males Females

Total

Cancer

Cardiovascular

Genitourinary

Chronic respiratory

Diabetes

Neurological

68%

86%

86%

82%

70%

45%

23%

32%

14%

14%

18%

30%

55%

77%

Fatal Non-fatal

Figure 3.12: Burden (DALYs) in those aged 75 years and over by broad cause group expressed

as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and nonfatal

outcomes, Australia, 2003

Ischaemic heart disease, stroke and dementia were the leading causes of burden in males,

together accounting for 34% of total male burden (Table 3.10). In females, ischaemic heart

disease, dementia and stroke were the leading causes, accounting for 42% of total burden.

The top 10 conditions account for 60.9% of the total burden in this age group.

54

Table 3.10: Leading causes of DALYs in those aged 75 years and over by sex, Australia, 2003

Rank Males DALYs

Per cent

of total Females DALYs

Per cent

of total

1 Ischaemic heart disease 55,680 19.3 Ischaemic heart disease 70,853 18.7

2 Stroke 21,834 7.5 Dementia 46,984 12.4

3 Dementia 21,095 7.3 Stroke 39,830 10.5

4 Prostate cancer 15,484 5.4 Type 2 diabetes 15,330 4.1

5 COPD 14,900 5.2 COPD 13,318 3.5

6 Lung cancer 13,533 4.7 Colorectal cancer 9,703 2.6

7 Type 2 diabetes 11,262 3.9 Lower respiratory tract infections 9,137 2.4

8 Colorectal cancer 8,442 2.9 Lung cancer 9,059 2.4

9 Adult-onset hearing loss 7,052 2.4 Breast cancer 8,995 2.4

10 Lower respiratory tract infections 6,395 2.2 Falls 7,814 2.1

3.5 Specific disease and injury categories

This section presents burden by 22 broad cause groupings (Table 3.11) and discusses the

eight largest of these in greater detail. The section ends with a short discussion on three

conditions (renal failure, vision loss and intellectual disability), the burden from which in the

previous sections is split across multiple subheadings depending on aetiology. However,

from a health service planning perspective there is value in presenting the aggregates for

these conditions.

55

Table 3.11: Burden (YLD, YLL and DALYs) by broad cause group, Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Cancers 87,463 6.5 411,953 32.2 499,416 19.0

Cardiovascular disease 104,429 7.7 369,365 28.9 473,794 18.0

Mental disorders 327,391 24.2 23,154 1.8 350,545 13.3

Neurological & sense disorders 258,638 19.1 54,127 4.2 312,766 11.9

Chronic respiratory diseases 115,398 8.5 71,339 5.6 186,737 7.1

Diabetes mellitus 111,536 8.2 32,295 2.5 143,831 5.5

Unintentional injuries 41,263 3.0 84,599 6.6 125,862 4.8

Musculoskeletal diseases 98,481 7.3 7,027 0.5 105,508 4.0

Genitourinary diseases 41,161 3.0 24,087 1.9 65,249 2.5

Intentional injuries 3,139 0.2 56,050 4.4 59,189 2.2

Diseases of the digestive system 30,246 2.2 27,710 2.2 57,957 2.2

Infectious & parasitic diseases 14,021 1.0 30,665 2.4 44,685 1.7

Acute respiratory infections 11,752 0.9 23,750 1.9 35,502 1.3

Neonatal causes 15,584 1.2 18,974 1.5 34,558 1.3

Congenital anomalies 16,331 1.2 16,897 1.3 33,228 1.3

Endocrine & metabolic disorders 14,968 1.1 13,598 1.1 28,565 1.1

Oral conditions 24,406 1.8 102 0.0 24,507 0.9

Skin diseases 18,130 1.3 2,173 0.2 20,302 0.8

Ill-defined conditions 8,781 0.6 2,536 0.2 11,317 0.4

Non-malignant neoplasms 3,209 0.2 7,694 0.6 10,903 0.4

Nutritional deficiencies 5,739 0.4 458 0.0 6,197 0.2

Maternal conditions 1,926 0.1 226 0.0 2,152 0.1

Total burden 1,353,992 100.0 1,278,778 100.0 2,632,770 100.0

Cancers

Cancer was responsible for 19.0% of the total burden of disease and injury in Australia in

2003 (Table 3.11), with lung, colorectal, breast and prostate cancer accounting for half of this

burden (Figure 3.13). Apart from the sex-specific cancers (that is, breast, cervical and uterine

cancers in females and prostate cancer in males), there were considerable sex differences in

the experience of cancer burden, with males having a greater share of the burden from

melanoma, colorectal cancer, lymphomas and lung cancer than females. The difference in

lung cancer between males and females was largely due to the higher prevalence of smoking

in males than females two or more decades ago. More than four-fifths of the total cancer

burden was due to mortality.

56

Total

Prostate cancer

Lung cancer

Lymphoma

Colorectal cancer

Pancreas cancer

Breast cancer

53%

100%

62%

56%

54%

50%

0%

47%

0%

38%

44%

46%

50%

100%

Males Females

Total

Pancreas cancer

Lung cancer

Lymphoma

Colorectal cancer

Breast cancer

Prostate cancer

82%

98%

93%

84%

81%

66%

63%

18%

2%

7%

16%

19%

34%

37%

Fatal Non-fatal

Figure 3.13: Cancer burden (DALYs) by specific cause expressed as: (a) proportions of

total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes,

Australia, 2003

Total cancer burden, both in absolute terms and when expressed as a rate per head of

population, increased exponentially until age 75, then declined (Figure 3.14). The

contribution from lung cancer was greatest at this age after which it declined in proportion

to other cancers. In males, the contribution from prostate cancer increased until old age,

whereas in females the contribution from breast cancer increased until age 60, then declined

in proportion to other cancers. The contribution from colorectal cancer was important across

all ages.

Lung

cancer

Colorectal

cancer

Breast

cancer

Prostate

Pancreas cancer

cancer

Lymphoma

Other

18%

13%

12%

4% 5% 7%

41%

57

0

50

100

150

0 20 40 60 80 100

Age

Males

Females

Figure 3.14: Cancer burden (DALYs) by age expressed as: (a) rates by sex, and (b) numbers by

specific cause, Australia, 2003

Lung cancer was the fourth leading cause of overall burden in males, while prostate and

colorectal cancers were the ninth and tenth, respectively. Breast cancer was the sixth leading

cause of overall burden in females, while lung cancer and colorectal cancer were eighth and

tenth, respectively (Table 3.1). Although cancer of the cervix was not a leading cause of death

in females, it is a cancer priority area because it is one of the few cancers where precancerous

lesions can and have been cost-effectively detected and treated through an

organised screening program. Moreover, a vaccine against human papilloma virus has

become available that has the potential to further reduce the burden of cervical cancer over

time. This illustrates that burden information should be used with other evidence to

determine health service priorities.

Table 3.12: Cancer burden (YLD, YLL and DALYs) by specific cause, Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Lung cancer 5,848 0.4 83,056 6.5 88,904 3.4

Colorectal cancer 11,873 0.9 51,732 4.0 63,605 2.4

Breast cancer 20,440 1.5 40,214 3.1 60,654 2.3

Prostate cancer 13,372 1.0 23,175 1.8 36,547 1.4

Pancreas cancer 561 0.0 22,119 1.7 22,680 0.9

Lymphoma 3,465 0.3 18,798 1.5 22,263 0.8

Other 31,905 2.4 172,859 13.5 204,763 7.8

Total cancer burden 87,463 6.5 411,953 32.2 499,416 19.0

Rate per 1,000

0

20

40

60

Number (thousands)

0 20 40 60 80 100

Age

Other

Lymphoma

Pancreas cancer

Prostate cancer

Breast cancer

Colorectal cancer

Lung cancer

58

Cardiovascular disease

Cardiovascular disease were responsible for 18.0% the total burden of disease and injury in

Australia in 2003 (Table 3.11), with ischaemic heart disease and stroke accounting for over

four-fifths of this burden (Figure 3.15). These diseases were also in the five leading causes of

overall burden (Table 3.1). The contribution from ischaemic heart disease was greater in

males than in females, while the reverse was the case for stroke. Nearly four-fifths of total

cardiovascular burden was due to mortality.

Ischaemic

heart

disease

Stroke

Peripheral

vascular

Other

56%

25%

4%

15% Total

IHD

Peripheral vascular

Stroke

53%

57%

57%

45%

47%

43%

43%

55%

Males Females

Total

IHD

Stroke

Peripheral vascular

78%

83%

71%

31%

22%

17%

29%

69%

Fatal Non-fatal

Figure 3.15: Cardiovascular burden (DALYs) by specific cause expressed as: (a) proportions

of total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes,

Australia, 2003

In contrast to cancer, the total cardiovascular burden per head of population continued

increasing until old age. This resulted in a larger proportion of the absolute burden at older

ages than for cancer (Figure 3.16). Ischaemic heart disease dominated across all ages.

59

0

200

400

Rate 1,000

0 20 40 60 80 100

Age

Males

Females

Figure 3.16: Cardiovascular burden (DALYs) by age expressed as: (a) rates by sex, and

(b) numbers by specific cause, Australia, 2003

Table 3.13: Cardiovascular burden (YLD, YLL and DALYs) by specific cause, Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Ischaemic heart disease 45,354 3.3 218,143 17.1 263,497 10.0

Stroke 33,763 2.5 84,699 6.6 118,462 4.5

Peripheral vascular disease 12,888 1.0 5,718 0.4 18,606 0.7

Inflammatory heart disease 3,689 0.3 12,215 1.0 15,904 0.6

Aortic aneurysm 209 0.0 11,129 0.9 11,338 0.4

Hypertensive heart disease 678 0.1 8,303 0.6 8,982 0.3

Other 7,848 0.6 29,157 2.3 37,005 1.4

Total cardiovascular burden 104,429 7.7 369,365 28.9 473,794 18.0

Mental disorders

Mental disorders were responsible for 13.3% of the total burden of disease and injury in

Australia in 2003 (Table 3.11), with anxiety & depression, alcohol abuse and personality

disorders accounting for almost three-quarters of this burden (Figure 3.17). There were

marked sex differences in the mental illness burden for particular disorders. The burden

from anxiety & depression was twice as high for females as for males. Conversely, the

burden from substance abuse was more than three times as high in males as in females.

Eating disorders occurred mainly in females. Autism spectrum disorders were much more

common in males, with females having just 15% of the total burden from these conditions.

per Number (thousands)

0

50

100

0 20 40 60 80 100

Age

Other

Inflammatory heart disease

Peripheral vascular disease

Stroke

Ischaemic heart disease

60

Seven per cent of the burden from mental disorders was due to mortality, most of which was

accounted for by fatal outcomes associated with substance abuse.

Heroin

dependence

Total

Autism

Alcohol dependence

Heroin dependence

Schizophrenia

Personality disorders

Anxiety & depression

47%

85%

80%

74%

54%

50%

34%

53%

15%

20%

26%

46%

50%

66%

Males Females

Total

Alcohol dependence

Heroin dependence

Schizophrenia

Autism

Anxiety & depression

Personality disorders

7%

42%

39%

1%

1%

0%

0%

93%

58%

61%

99%

99%

100%

100%

Fatal Non-fatal

Figure 3.17: Mental disorder burden (DALYs) by specific cause expressed as: (a) proportions of

total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes, Australia,

2003

The burden from mental disorders both in absolute terms and when expressed as a rate per

head of population was greater in early adulthood than at other ages (Figure 3.18). This was

partly due to the peak in new cases of chronic mental illnesses at this life stage, the burden of

which was experienced throughout adult life. Anxiety & depression contributed most until

age 60, after which the contribution from alcohol abuse and personality disorders was more

prominent.

Anxiety &

depression

Alcohol

dependence

Personality

disorders

Schizophrenia

Heroin

dependence

Autism

Other

55%

10%

9%

8%

5%

4%

10%

61

0

20

0 20 40 60 80 100

Age

Males

Females

thousands)

Figure 3.18: Mental disorder burden (DALYs) by age expressed as: (a) rates by sex, and

(b) numbers by specific cause, Australia, 2003

In males, anxiety & depression was the third leading cause of overall male burden, while

alcohol abuse was the fourteenth. In females, anxiety & depression was the leading cause of

overall female burden, while isolated personality disorders was the thirteenth (Table 3.1).

Anxiety & depression also carries with it an increased risk of ischaemic heart disease and

suicide. When this risk was accounted for, the burden attributable to anxiety & depression

increased from 7.3% to 8.2% of total burden (Table 3.14). The contribution of other mental

disorders to the burden of suicide follows in the section on injuries.

Table 3.14: Mental disorder burden (YLD, YLL and DALYs) by specific cause, Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Anxiety & depression 191,452 14.1 334 0.0 191,786 7.3

Alcohol abuse 19,861 1.5 14,255 1.1 34,116 1.3

Personality disorders 32,587 2.4 — 0.0 32,587 1.2

Schizophrenia 27,250 2.0 252 0.0 27,502 1.0

Heroin or polydrug abuse 10,287 0.8 6,552 0.5 16,839 0.6

Autism spectrum disorders 13,756 1.0 110 0.0 13,866 0.5

Other 32,198 2.4 1,652 0.1 33,850 1.3

Total mental disorder burden 327,391 24.2 23,154 1.8 350,545 13.3

Ischaemic heart disease attributable to

anxiety & depression 1,399 0.1% 5,689 0.4% 7,088 0.3%

Suicide attributable to anxiety & depression 200 0.0% 16,708 1.3% 16,908 0.6%

Total burden attributable to anxiety &

depression 193,051 14.3% 22,731 1.8% 215,783 8.2%

40

Rate per 1,000

0

50

Number (0 20 40 60 80 100

Age

Other

Schizophrenia

Personality disorders

Alcohol dependence

Anxiety & depression

62

Neurological and sense disorders

Neurological & sense disorders were responsible for 11.9% of the total burden of disease and

injury in Australia in 2003 (Table 3.11), with dementia, adult-onset hearing loss and vision

loss accounting for two-thirds of this burden (Figure 3.19). There were marked sex

differentials in the attribution of the neurological & sense disorder burden to particular

conditions. Females contributed three times as much to migraine and twice as much to

dementia than males. Conversely, the burden from hearing loss was twice as high in males

as in females. The greater preponderance of burden from dementia and vision disorders in

females was largely due to higher life expectancy in females than males. Only 17% of the

burden from neurological & sense disorders was due to mortality.

Total

Hearing loss

Epilepsy

Parkinson's disease

Vision loss

Dementia

Migraine

47%

66%

57%

51%

43%

36%

27%

53%

34%

43%

49%

57%

64%

73%

Males Females

Total

Epilepsy

Dementia

Parkinson's disease

Migraine

Vision loss

Hearing loss

17%

42%

26%

21%

0%

0%

0%

83%

58%

74%

79%

100%

100%

100%

Fatal Non-fatal

Figure 3.19: Neurological & sense disorder burden (DALYs) by specific cause expressed

as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and

non-fatal outcomes, Australia, 2003

The burden from neurological & sense disorders, both in absolute terms and when expressed

as a rate per head of population, increased with age, with a small but important peak in early

adulthood due to the contribution of migraine (Figure 3.20). The contribution from dementia

increased from middle age to more than half the burden in the elderly and was more

pronounced in females than in males. Conversely, the contribution from hearing loss

decreased with age and was more pronounced in males than in females. Vision loss made a

smaller but important contribution across all ages.

Dementia

Adult-onset

hearing

loss

Vision

loss

Parkinson's

disease

Migraine

Epilepsy

Other

30%

15% 21%

9%

7%

5%

13%

63

0

50

100

150

0 20 40 60 80 100

Age

Males

Females

Figure 3.20: Neurological & sense disorder burden (DALYs) by age expressed as: (a) rates by sex,

and (b) numbers by specific cause, Australia, 2003

Adult-onset hearing loss, dementia and Parkinson’s disease were the seventh, eleventh and

twentieth leading causes of overall male burden. In females, dementia was ranked the fifth

leading cause of overall female burden, with hearing loss, migraine and Parkinson’s disease

ranked eleventh, fourteenth and eighteenth (Table 3.1).

Table 3.15: Neurological & sense disorder burden (YLD, YLL and DALYs) by specific cause,

Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Dementia 70,296 5.2 24,103 1.9 94,399 3.6

Adult-onset hearing loss 64,853 4.8 0 0.0 64,853 2.5

Vision loss 47,865 3.5 9 0.0 47,875 1.8

Parkinson’s disease 21,157 1.6 5,695 0.4 26,852 1.0

Migraine 21,841 1.6 7 0.0 21,848 0.8

Epilepsy 8,601 0.6 6,220 0.5 14,821 0.6

Other 24,025 1.8 18,092 1.4 42,118 1.6

Total neurological & sense

disorder burden 258,638 19.1 54,127 4.2 312,766 11.9

Rate per 1,000

0

20

40

Number (thousands)

0 20 40 60 80 100

Age

Other

Migraine

Parkinson's disease

Vision loss

Adult-onset hearing loss

Dementia

64

Chronic respiratory diseases

Chronic respiratory diseases were responsible for 7.1% of total burden of disease and injury

in Australia in 2003 (Table 3.11), with chronic obstructive pulmonary disease and asthma

accounting for 46% and 34% of this burden, respectively (Figure 3.21). Males had a greater

share of chronic obstructive pulmonary disease burden than females because of the greater

prevalence of smoking in males 20 to 30 years ago. Fifty-four per cent of the burden from

chronic obstructive pulmonary disease was due to mortality, whereas only 6% of the asthma

burden was due to mortality.

Total

COPD

Asthma

53%

57%

46%

47%

43%

54%

Males Females

Total

COPD

Asthma

38%

54%

6%

62%

46%

94%

Fatal Non-fatal

Figure 3.21: Chronic respiratory disease burden (DALYs) by specific cause expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and nonfatal

outcomes, Australia, 2003

The burden from chronic respiratory diseases per head of population in both sexes was

higher in childhood than in middle age, after which it increased exponentially (Figure 3.22).

This was due to the high incidence of asthma in childhood, particularly in boys, and then

remission as the body matures. Chronic obstructive pulmonary disease, largely from

smoking, was the leading cause of chronic respiratory disease burden from middle age

onwards.

COPD

Asthma

Other

46%

34%

20%

65

0

20

40

60

Rate 1,000

0 20 40 60 80 100

Age

Males

Females

Figure 3.22: Chronic respiratory disease burden (DALYs) by age expressed as: (a) rates by sex,

and (b) numbers by specific cause, Australia, 2003

Chronic obstructive pulmonary disease was the sixth leading cause of overall male burden,

with asthma at thirteenth. In females, these conditions were ranked seventh and ninth in the

leading causes of overall female burden, respectively (Table 3.1).

Table 3.16: Chronic respiratory disease burden (YLD, YLL and DALYs) by specific cause,

Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

COPD 39,543 2.9 47,208 3.7 86,751 3.3

Asthma 59,054 4.4 4,045 0.3 63,100 2.4

Other 16,801 1.2 20,086 1.6 36,887 1.4

Total chronic respiratory disease

burden 115,398 8.5 71,339 5.6 186,737 7.1

Injuries

Injuries were responsible for 7.0% of the total burden of disease and injury in Australia in

2003 (Table 3.11), with suicide & self-inflicted injuries, road traffic accidents and falls

accounting for nearly two-thirds of this burden (Figure 3.23). The burden in males was

greater than females for most causes of injury. Males accounted for 73% of the burden due to

road traffic accidents and 78% for suicide & self-inflicted injuries. The burden from falls, on

the other hand, was equally distributed amongst males and females. Seventy-six per cent of

the overall injury burden was due to mortality.

per 0

10

20

30

Number (thousands)

0 20 40 60 80 100

Age

Other

Asthma

COPD

66

Total

Suicide & self-inflicted

Road traffic accidents

Homicide & violence

Poisoning

Falls

70%

78%

73%

71%

57%

50%

30%

22%

27%

29%

43%

50%

Males Females

Total

Suicide & self-inflicted

Poisoning

Road traffic accidents

Homicide & violence

Falls

76%

99%

97%

86%

72%

47%

24%

1%

3%

14%

28%

53%

Fatal Non-fatal

Figure 3.23: Injury burden (DALYs) by specific cause expressed as: (a) proportions of total,

(b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes, Australia,

2003

The injury burden in males was greater in early adulthood than at other ages, both in

absolute terms and when expressed as a rate per head of population (Figure 3.24). For

females, the absolute burden was greatest in the very young, while the rate increased with

age from a third of the male rate at early adulthood to similar levels at old age. The peak in

absolute burden in early adulthood was due to the high mortality from road traffic accidents

and suicide at this life stage. The distribution of injury burden by cause was similar between

males and females at all ages.

In males, suicide & self-inflicted injuries and road traffic accidents were the eighth and

twelfth leading cause of overall male burden. In females, only falls were in the 20 leading

causes of overall female burden at seventeenth (Table 3.1).

0

10

20

30

Rate 1,000

0 20 40 60 80 100

Age

Males

Females

Figure 3.24: Injury burden (DALYs) by age expressed as: (a) rates by sex, and (b) numbers by

specific cause, Australia, 2003

per Suicide &

self-inflicted

Road

traffic

Falls accidents

Poisoning

Homicide &

violence

Other

27%

23%

14%

7%

5%

24%

0

10

20

Number (thousands)

0 20 40 60 80 100

Age

Other

Homicide & violence

Poisoning

Falls

Road traffic accidents

Suicide & self-inflicted

67

Suicide & self-inflicted injuries were responsible for 27% of the total injury burden in

Australia in 2003 (Figure 3.23), with anxiety & depression and alcohol abuse accounting for

nearly three-quarters of this burden (Figure 3.25). The burden in males was greater than in

females for all major causes of suicide & self-inflicted injury.

Anxiety &

depression

Alcohol

dependence

Bipolar

disorder

Schizophrenia

Personality

disorders

Heroin

dependence

Other

48%

25%

6%

5%

4%

4%

9% Total

Heroin dependence

Bipolar disorder

Schizophrenia

Personality disorders

Alcohol dependence

Anxiety & depression

78%

92%

91%

87%

84%

78%

73%

22%

8%

9%

13%

16%

22%

27%

Males Females

Total

Schizophrenia

Heroin dependence

Bipolar disorder

Personality disorders

Anxiety & depression

Alcohol dependence

99%

99%

99%

99%

99%

99%

99%

1%

1%

1%

1%

1%

1%

1%

Fatal Non-fatal

Figure 3.25: Suicide burden (DALYs) by specific cause expressed as: (a) proportions of total,

(b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes, Australia, 2003

Table 3.17: Injury burden (YLD, YLL and DALYs) by specific cause, Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Suicide & self-inflicted injuries 537 0.0 49,379 3.9 49,916 1.9

Road traffic accidents 6,073 0.4 36,352 2.8 42,425 1.6

Falls 13,995 1.0 12,391 1.0 26,386 1.0

Poisoning 326 0.0 11,720 0.9 12,046 0.5

Homicide & violence 2,597 0.2 6,624 0.5 9,221 0.4

Other transport accidents 2,873 0.2 5,728 0.4 8,601 0.3

Other 18,001 1.3 18,454 1.4 36,454 1.4

Total injury burden 44,402 3.3 140,648 11.0 185,050 7.0

Diabetes

Diabetes was responsible for 5.5% of the total burden of disease and injury in Australia in

2003 (Table 3.11), with Type 2 diabetes accounting for 92% of this burden. Eighty-five per

cent of the total diabetes burden was due to diabetes per se (that is, the experience of being

diabetic regardless of complications), with the remainder being due to complications such as

68

neuropathy, peripheral vascular disease (PVD), and diabetic foot (Figure 3.26). Twenty-two

per cent of the total diabetes burden was due to mortality.

Figure 3.26: Diabetes burden (DALYs) by specific cause expressed as: (a) proportions of

total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes

The risk of burden from diabetes in both sexes increased linearly until age 85 then declined

(Figure 3.27). The contribution from diabetes per se dominated at all ages. Diabetes ranked

second and fourth in the 20 leading causes of burden for males and females, respectively

(Table 3.1).

Figure 3.27: Diabetes burden (DALYs) by age expressed as: (a) rates by sex, and (b) numbers by

specific cause, Australia, 2003

Diabetes

per se

Neuropathy

PVD

Diabetic

foot Other

85%

5%

4%3%4% Total

Diabetic foot

Diabetes per se

Neuropathy

PVD

54%

67%

54%

52%

49%

46%

33%

46%

48%

51%

Males Females

Total

Diabetes per se

Neuropathy

PVD

Diabetic foot

22%

27%

0%

0%

0%

78%

73%

100%

100%

100%

Fatal Non-fatal

0

50

100

150

Rate per 1,000

0 20 40 60 80 100

Age

Males

Females

0

50

100

Number (thousands)

0 20 40 60 80 100

Age

Other

Diabetic foot

PVD

Neuropathy

Diabetes per se

69

Diabetes also carries with it an increased risk of ischaemic heart disease and stroke. When

this risk was accounted for, the burden attributable to diabetes increased to 8.3% of total

burden (Table 3.18).

Table 3.18: Diabetes burden (YLD, YLL and DALYs) by specific cause, Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Diabetes per se 89,252 6.6 32,295 2.5 121,547 4.6

Neuropathy 6,500 0.5 — 0.0 6,500 0.2

Peripheral vascular disease 5,917 0.4 — 0.0 5,917 0.2

Diabetic foot 3,672 0.3 — 0.0 3,672 0.1

Amputation 2,455 0.2 — 0.0 2,455 0.1

Retinopathy 1,258 0.1 — 0.0 1,258 0.0

Other(a) 2,483 0.2 — 0.0 2,483 0.1

Total diabetes burden 111,536 8.2 32,295 2.5 143,831 5.5

Ischaemic heart disease

attributable to diabetes 8,494 0.6 45,948 3.6 54,442 2.1

Stroke attributable to diabetes 3,985 0.3 16,260 1.3 20,245 0.8

Total burden attributable to

diabetes 124,015 9.2 94,503 7.4 218,518 8.3

(a) Includes renal failure.

Musculoskeletal diseases

Musculoskeletal diseases were responsible for 4.0% of the total burden of burden and injury

in Australia in 2003 (Table 3.11), with osteoarthritis, back pain and rheumatoid arthritis

accounting for over three-quarters of this burden (Figure 3.28). Only 7% of the

musculoskeletal burden was due to mortality. The sex difference evident in the burden due

to osteoarthritis and rheumatoid arthritis was mainly a result of the higher female life

expectancy, which in turn allowed for more incident cases of this disease. The lack of a

plausible physiological or occupational explanation for the large sex difference in burden

from occupational overuse syndrome (OOS) provides support to the notion that this

syndrome is not a single entity.

The risk of burden from musculoskeletal diseases in both sexes increased until age 80 then

declined (Figure 3.29). The contribution of back pain was relatively constant until age 70 then

declined in proportion to the contribution from osteoarthritis.

Osteoarthritis and back pain conditions ranked seventeenth and eighteenth in the 20 leading

causes of burden for males, and twelfth and fifteenth for females (Table 3.1).

70

Osteoarthritis

Back pain

Rheumatoid

arthritis

Slipped

disc

Occupational

overuse

syndrome

Other

33%

28%

16%

6%

5%

13% Total

Slipped disc

Back pain

Osteoarthritis

Rheumatoid arthritis

OOS

42%

56%

49%

42%

28%

14%

58%

44%

51%

58%

72%

86%

Males Females

Total

Rheumatoid arthritis

Osteoarthritis

Back pain

Slipped disc

OOS

7%

10%

1%

1%

1%

0%

93%

90%

99%

99%

99%

100%

Fatal Non-fatal

Figure 3.28: Musculoskeletal disease burden (DALYs) by specific cause expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and

non-fatal outcomes, Australia, 2003

0

10

20

Rate 1,000

0 20 40 60 80 100

Age

Males

Females

0

5

10

15

(0 20 40 60 80 100

Age

Other

Occupational overuse syndrome

Slipped disc

Rheumatoid arthritis

Back pain

Osteoarthritis

Figure 3.29: Musculoskeletal disease burden (DALYs) by age expressed as: (a) rates by sex, and

(b) numbers by specific cause, Australia, 2003

per Number thousands)

71

Table 3.19: Musculoskeletal disease burden (YLD, YLL and DALYs) by specific cause, Australia,

2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Osteoarthritis 34,204 2.5 374 0.0 34,578 1.3

Back pain 29,484 2.2 173 0.0 29,658 1.1

Rheumatoid arthritis 15,215 1.1 1,626 0.1 16,841 0.6

Slipped disc 6,089 0.4 31 0.0 6,120 0.2

Occupational overuse syndrome 4,953 0.4 — 0.0 4,953 0.2

Gout 1,813 0.1 175 0.0 1,988 0.1

Other 6,722 0.5 4,647 0.4 11,369 0.4

Total musculoskeletal disease

burden 98,481 7.3 7,027 0.5 105,508 4.0

Alternative categories for selected conditions

The burden from intellectual disability, renal failure and vision disorders was attributed to

multiple underlying causes in the primary listing of diseases and injuries and is therefore not

discussed explicitly in the above sections. The burden from intellectual disability, apart from

congenital conditions (for example Down syndrome), was divided among epilepsy, autism

spectrum disorders, infectious diseases, injuries, and perinatal conditions. The burden from

renal failure was divided among diabetic nephropathy, the injury category of medical

misadventure (analgesic nephropathy), and congenital conditions (dysplasia, polycystic

kidneys). The burden from total vision loss was divided among diabetic retinopathy,

glaucoma, cataract, refraction errors, age-related macular degeneration and other causes of

vision loss. The total burden from intellectual disability, renal failure and total vision loss

after re-aggregation was 1.7%, 2.6% and 2.1%, respectively (Table 3.20).

Table 3.20: Aggregated burden (YLD, YLL and DALYs) for selected conditions, Australia, 2003

Cause YLD

Per cent

of total YLL

Per cent

of total DALYs

Per cent

of total

Intellectual disability 20,999 1.6 23,189 1.8 44,187 1.7

Renal failure 3,809 0.3 64,912 5.1 68,721 2.6

Total vision loss 50,671 3.7 4,868 0.4 55,539 2.1

72

4 Risks to health in Australia

4.1 Overview

This chapter discusses the contribution of a number of health risks to the burden of disease

and injury in Australia for 2003. The analyses are not meant to be comprehensive since

choices had to be made about which risks to include on the basis of the availability of the

following:

1. Good evidence of a causal association between the exposure to the risk and the health

outcomes

2. Current estimates from reputable epidemiological studies of the relative risk involved

3. Reliable estimates of exposure in the Australian population to the health risk.

The outcome of these considerations was a set of 14 selected health risks as outlined in Table

4.1. Several important dietary factors were considered for inclusion (for example sodium and

saturated fat) as part of these deliberations, but were ultimately excluded due to inadequate

data on exposure. With the exception of low fruit and vegetable consumption, therefore, the

impact of ‘poor diet’ is measured indirectly through the assessments for high body mass,

blood cholesterol and blood pressure. Similarly, lack of data on prevalence and outcome

prevented estimation of the burden of intimate partner violence in males.

Table 4.1: Fourteen selected risks to health discussed in this report

Lifestyle behaviours Physiological states Social and environmental factors

1. Tobacco 7. High body mass 11. Urban air pollution

2. Alcohol 8. High blood pressure 12. Intimate partner violence

3. Physical inactivity 9. High blood cholesterol 13. Child sexual abuse

4. Illicit drugs 10. Osteoporosis 14. Occupational exposures & hazards

5. Low fruit and vegetable consumption

6. Unsafe sex

It is important to remember several points when interpreting the results in the following

sections.

Firstly, health risks tend to cluster around ‘high risk’ individuals who experience more than

one exposure (for example smokers tend to be drinkers). This combination of exposures may

produce higher or lower levels of overall risk as a result of complex interaction effects. The

analyses presented in this chapter do not explicitly account for these interactions, except to

the extent to which confounding was controlled for in the studies from which the exposure–

outcome relationships were derived.

Secondly, the causal paths between a number of related health risks and their eventual

health outcomes can be complicated. For example, physical inactivity can lead to obesity,

which can cause hypertension or high blood cholesterol, which can ultimately lead to

cardiovascular disease. Most of the analyses presented in this chapter only measure the effect

of a risk independent of the other exposures and irrespective of the risk’s place in a causal

73

path. The important implication here is that such analyses are not additive. Using the

example above, the burden attributable to physical inactivity is estimated to be 23.7% of total

cardiovascular disease burden, while that for high body mass, high blood cholesterol and

high blood pressure was 19.5%, 34.5% and 42.1% of cardiovascular disease, respectively

(Table 4.2). The burden attributable to these health risks in combination, however, is not the

sum of burden from each risk (that is, the combined burden is not 119.9%). This is because

the combined effect of these risks has to be expressly calculated rather than derived from the

addition of their individual effects. Ignoring shared causal paths in this example leads to

obvious over-estimation of the combined effect.

To illustrate the total ‘explanatory’ power of the 14 risk factors, the chapter begins with an

analysis that accounts for many of the overlaps between risks that share causal paths. This is

done using the ‘joint effects’ method developed for the WHO Comparative Risk Assessment

project (Ezzati et al. 2004b). Sensitivity analyses indicate that overall results based on this

approach are relatively robust to the underlying assumptions; apportioning the combined

overall risk back to each contributing risk factor is more difficult, however, and is much

more sensitive to assumptions. Therefore, only the former analyses are presented in this

report. Further details on the methods used for estimating joint effects are provided in

Chapter 2.

4.2 Combined effect of 14 selected risks to health

The 14 selected risk factors presented in this chapter together explained 32.2% of the total

burden of disease and injury in Australia in 2003 (Table 4.2). These risk factors explained

35.1% and 29.1% of the total burden in males and females respectively (Table 4.3). This

indicates that there is considerable potential to further reduce burden in Australia through

interventions that target these health risks, each of which contribute to more than one health

outcome. Additional evidence on the (cost-) effectiveness of such interventions may guide

the setting of health service priorities to meet this objective.

Key findings about broad cause groups were:

• Ten of the risks were associated with cancer and together explained 32.9% of the total

burden from this cause. The majority was explained by tobacco. The contributions of the

other risk factors (physical inactivity, high body mass, alcohol, occupational exposure,

low fruit and vegetable consumption, air pollution and unsafe sex (through the link

between the human papilloma virus and cancer of the cervix)) were comparatively much

smaller.

• Twelve of the risks were associated with cardiovascular disease and together explained

69.3% of the burden from this group of causes; for ischaemic heart disease, this figure

was 85.2%. High blood pressure and high blood cholesterol were the largest

contributors, followed by physical inactivity, high body mass, tobacco, and low fruit and

vegetable consumption. The very low prevalence of smoking in elderly Australians, who

are most affected by cardiovascular disease, explains the relatively small contribution of

tobacco to this disease.

• Four of the risks were associated with mental disorders and together explained 26.9% of

the burden from this cause. Alcohol and illicit drugs contributed in roughly equal

proportions. Intimate partner violence and child sexual abuse contributed less but were

the only risks implicated in the large burden from anxiety and depression.

74

• Three of the risks were associated with neurological and sense disorders, and together

explained only 0.2% of the burden from these disorders. This reflects lack of knowledge

about causation in this group. Ultraviolet light, causing cataract, is probably the most

obvious omitted risk factor in this disease category but the burden of cataract is small

because surgical treatment is widely available.

• Seven of the risks were associated with injury and together explained 31.7% of the

burden from this cause. Alcohol was by far the largest contributor, followed by

occupational exposures and hazards, illicit drugs, intimate partner violence,

osteoporosis, child sexual abuse, and tobacco.

• Two of the risks were associated with Type 2 diabetes (including the proportion of

cardiovascular disease caused by diabetes) and together explained 60.1% of the burden

from this cause. High body mass was by far the largest contributor to this disease.

Table 4.2: Individual and joint burden (DALYs) attributable to 14 selected risk factors by broad

cause group, Australia, 2003

Broad cause group

Cancer CVD Mental

Neurological

Injury Diabetes Other

All

causes

Total burden (‘000) 499.4 473.8 350.5 312.8 185.1 143.8 667.4 2,632.8

Attributable burden (%)(a)

Tobacco 20.1 9.7 — –0.6 0.5 — 8.9 7.8

High blood pressure — 42.1 — — — — — 7.6

High body mass 3.9 19.5 — — — 54.7 1.1 7.5

Physical inactivity 5.6 23.7 — — — 23.7 >–0.1 6.6

High blood cholesterol — 34.5 — — — — — 6.2

Alcohol

Harmful effects 3.1 0.9 9.7 — 18.1 — <0.1 3.3

Beneficial effects — –5.6 — — — — >–0.1 –1.0

Net effects 3.1 –4.7 9.7 — 18.1 — <0.1 2.3

Low fruit & vegetable

consumption 2.0 9.6 — — — — >–0.1 2.1

Illicit drugs — <0.1 8.0 — 3.6 — 2.5 2.0

Occupational exposures &

hazards 3.1 0.4 — 0.8 4.7 — 3.4 2.0

Intimate partner violence 0.5 0.3 5.5 0.1 2.5 — 0.2 1.1

Child sexual abuse <0.1 <0.1 5.8 — 1.4 — <0.1 0.9

Urban air pollution 0.8 2.7 — — — — 0.4 0.7

Unsafe sex 1.0 — — — — — 1.4 0.6

Osteoporosis — — — — 2.4 — — 0.2

Joint effect(b) 32.9 69.3 26.9 0.2 31.7 60.1 17.2 32.2

(a) Attributable burden within each column is expressed as a percentage of total burden for that column.

(b) Figures for joint effects are not column totals. See Section 4.1 for further details.

The 14 selected risk factors presented in this chapter had a differential impact on health in

terms of both sex and age (Table 4.3). In the 0–44 year-old age group, alcohol and illicit drugs

75

were the leading causes of burden in males, mental disorders (alcohol abuse, and heroin and

polydrug abuse) and injuries (suicide and self-inflicted injuries, and road traffic accidents)

being the predominant health outcomes from these risks. In this age group, 23.6% of total

male burden and 17.9% of total female burden was explained by the 14 risks in combination.

In females, intimate partner violence and child sexual abuse were the leading causes in this

age group, anxiety and depression and suicide and self-inflicted injuries being the

predominant health outcomes from these risks.

In the 45–64 year-old age group, high body mass and tobacco were the leading causes in both

sexes, Type 2 diabetes, ischaemic heart disease, stroke, lung cancer and chronic obstructive

pulmonary disease (COPD) being the predominant health outcomes from these risks. The

proportion of total burden in this age group that is explained by the 14 risks in combination

was 43.8% in males and 33.6% in females.

In the 65 years and over age group, high blood pressure was the leading cause in both sexes,

followed by tobacco in males and high blood cholesterol in females. The predominant health

outcomes from both high blood pressure and high blood cholesterol are ischaemic heart

disease and stroke. For tobacco, the predominant health outcomes are lung cancer and

COPD. The proportion of total burden in this age group that is explained by the 14 risks in

combination was 38.4% and 34.8% in males and females, respectively.

Table 4.3: Individual and joint burden (DALYs) attributable to 14 selected risk factors by sex and

age group, Australia, 2003

Males Females

0–44 45–64 65+ All ages 0–44 45–64 65+ All ages

Total burden (’000) 448.8 382.5 533.4 1,364.6 406.0 299.1 563.0 1,268.2

Attributable burden (%)(a)

Tobacco 1.9 14.7 12.5 9.6 1.1 8.7 7.6 5.8

High blood pressure 0.8 7.8 13.8 7.8 <0.1 4.0 14.2 7.3

High body mass 3.3 13.3 7.5 7.7 2.6 12.1 8.1 7.3

Physical inactivity 1.8 9.0 8.5 6.4 1.9 8.4 9.6 6.8

High blood cholesterol 1.9 9.6 8.3 6.6 0.7 5.1 9.9 5.8

Alcohol

Harmful effects 8.1 5.5 1.8 4.9 2.2 2.4 0.8 1.6

Beneficial effects –0.3 –1.5 –1.5 –1.1 –0.2 –0.9 –1.5 –0.9

Net effects 7.8 4.0 0.3 3.8 2.0 1.4 –0.6 0.7

Low fruit & vegetable

consumption 0.8 4.1 3.3 2.7 0.3 1.7 2.2 1.5

Illicit drugs 5.7 1.9 0.6 2.7 2.4 1.1 0.4 1.2

Occupational exposures &

hazards 2.7 4.2 1.4 2.6 1.6 2.4 0.4 1.3

Intimate partner violence — — — — 4.8 2.8 0.3 2.3

Child sexual abuse 0.6 0.3 <0.1 0.3 3.4 1.7 <0.1 1.5

Urban air pollution 0.2 0.9 1.2 0.8 0.1 0.6 1.2 0.7

Unsafe sex 0.8 0.4 0.2 0.5 1.0 0.9 0.4 0.7

Osteoporosis — <0.1 0.2 <0.1 — <0.1 0.6 0.3

Joint effect(b) 23.6 43.8 38.4 35.1 17.9 33.6 34.8 29.1

(a) Attributable burden within each column is expressed as a percentage of total burden for that column.

(b) Figures for joint effects are not column totals. See Section 4.1 for further details.

76

4.3 Individual contribution of 14 selected risks to

health

Tobacco

Tobacco was responsible for 7.8% of the total burden of disease and injury in Australia in

2003 (Table 4.4), with lung cancer, COPD and ischaemic heart disease accounting for more

than three-quarters of this burden (Figure 4.1). Of the 14 risk factors examined, tobacco was

responsible for the largest amount of burden across all ages in males (Table 4.3). Almost

two-thirds of the burden from tobacco was experienced by males due to the higher

prevalence 20 to 30 years ago of smoking in males compared with females. More than threequarters

of the burden from tobacco was due to mortality (Figure 4.1). Because of the long

lag time between smoking and many of its ill effects on health, the health benefits of recent

favourable trends in smoking prevalence will not be fully realised until many years in the

future.

The rate of burden from tobacco per head of population increased with age until 75 and the

absolute burden was concentrated between the ages of 55 and 75. The contribution from lung

cancer dominated at most ages but was overtaken by contributions from COPD and

ischaemic heart disease in the elderly (Figure 4.2).

Table 4.4: Deaths and burden (DALYs) attributable to tobacco by specific cause, Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Lung cancer 6,309 4.8 72,213 2.7

COPD 4,175 3.2 54,492 2.1

Ischaemic heart disease 1,962 1.5 31,435 1.2

Stroke 577 0.4 11,812 0.4

Oesophagus cancer 572 0.4 6,248 0.2

Other 1,916 1.4 28,588 1.1

Total attributable 15,511 11.7 204,788 7.8

77

Total

IHD

Oesophagus cancer

Lung cancer

Stroke

COPD

64%

73%

71%

65%

61%

58%

36%

27%

29%

35%

39%

42%

Males Females

Total

Oesophagus cancer

Lung cancer

IHD

COPD

Stroke

78%

94%

93%

80%

62%

57%

22%

6%

7%

20%

38%

43%

Fatal Non-fatal

Figure 4.1: Burden (DALYs) attributable to tobacco by specific cause expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and

non-fatal outcomes, Australia, 2003

0

20

40

60

Rate per 1,000

0 20 40 60 80 100

Age

Males

Females

Number thousands)

Figure 4.2: Burden (DALYs) attributable to tobacco by age expressed as: (a) rates by sex, and

(b) numbers by specific cause, Australia, 2003

High blood pressure

High blood pressure was responsible for 7.6% of the total burden of disease and injury in

Australia in 2003 (Table 4.5), with ischaemic heart disease and stroke accounting for 93% of

Lung

cancer

COPD

Ischaemic

heart

disease

Stroke

Oesophagus

cancer

Other

35%

27%

15%

6% 3%

14%

0

10

20

30

(0 20 40 60 80 100

Age

Other

Oesophagus cancer

Stroke

Ischaemic heart disease

COPD

Lung cancer

78

this burden (Figure 4.3). Of the 14 risk factors examined, high blood pressure was

responsible for the greatest amount of burden in the 65 years or over age group in both sexes

(Table 4.3). Overall, the burden from high blood pressure was somewhat greater in males

and 81% was due to mortality.

The rate of burden from high blood pressure per head of population increased with age and

the absolute burden was concentrated around old age (Figure 4.4). The contributions from

ischaemic heart disease and stroke dominated across all ages.

Table 4.5: Deaths and burden (DALYs) attributable to high blood pressure by specific cause,

Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Ischaemic heart disease 14,089 10.7 125,461 4.8

Stroke 6,603 5.0 59,962 2.3

Other 1,812 1.4 13,893 0.5

Total attributable 22,504 17.0 199,315 7.6

Ischaemic

heart

disease

Stroke

Other

63%

30%

7% Total

IHD

Stroke

54%

58%

47%

46%

42%

53%

Males Females

Total

IHD

Stroke

81%

83%

76%

19%

17%

24%

Fatal Non-fatal

Figure 4.3: Burden (DALYs) attributable to high blood pressure by specific cause expressed as: (a)

proportions of total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal outcomes,

Australia, 2003

79

Rate 1,000

Figure 4.4: Burden (DALYs) attributable to high blood pressure by age expressed as: (a) rates by

sex, and (b) numbers by specific cause, Australia, 2003

High body mass

The body mass index (BMI) is a measure of weight in kilograms over height in metres

squared and is typically categorised into under weight (BMI<20), normal weight

(20􀂔BMI<25), over weight (25􀂔BMI<30) and obese (BMI􀂕30). Rather than use these

categories, the health effects of ‘high body mass’ in the following analyses were estimated

using new methods in which BMI is measured on a continuous scale and risk is assessed

against a minimum counterfactual distribution with a mean of 21 and a SD of 1 (see

Appendix 2). This means that risk is attributed to all people in the population with a BMI of

greater than 21, with the degree of risk increasing exponentially above this value. The

consequence of this approach is that some of the attributable risk from high body mass

comes from the large proportion of the population that is not over weight or obese in the

conventional sense, but whose risk of disease is elevated, at least to some degree.

High body mass was responsible for 7.5%of the total burden of disease and injury in

Australia in 2003 (Table 4.6), with Type 2 diabetes and ischaemic heart disease (IHD)

accounting for almost three-quarters of this burden (Figure 4.5). Of the 14 risk factors

examined, high body mass accounted for the greatest amount of burden in the 45–64 year

age group in females (Table 4.3). The burden from high body mass was greater in males due

to the higher incidence of Type 2 diabetes itself and the associated cardiovascular

complications. Half of the burden from high body mass was due to mortality (Figure 4.5).

The rate of burden from high body mass per head of population increased with age; the

absolute burden was concentrated between the ages of 55 and 75. The contributions from

Type 2 diabetes and ischaemic heart disease dominate across all ages (Figure 4.6).

0

100

200

per 0 20 40 60 80 100

Age

Males

Females

0

20

40

Number (thousands)

0 20 40 60 80 100

Age

Other

Stroke

Ischaemic heart disease

80

Table 4.6: Deaths and burden (DALYs) attributable to high body mass by specific cause, Australia,

2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Type 2 diabetes 1,381 1.0 78,688 3.0

Ischaemic heart disease 4,914 3.7 66,533 2.5

Stroke 1,528 1.2 22,218 0.8

Colorectal cancer 721 0.5 9,920 0.4

Breast cancer 379 0.3 7,125 0.3

Other 602 0.5 13,148 0.5

Total attributable 9,525 7.2 197,632 7.5

Total

IHD

Colorectal cancer

Type 2 diabetes

Stroke

Breast cancer

53%

64%

54%

54%

50%

0%

47%

36%

46%

46%

50%

100%

Males Females

Total

Colorectal cancer

IHD

Breast cancer

Stroke

Type 2 diabetes

50%

81%

80%

67%

61%

17%

50%

19%

20%

33%

39%

83%

Fatal Non-fatal

Figure 4.5: Burden (DALYs) attributable to high body mass by specific cause expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal

outcomes, Australia, 2003

Type 2

diabetes

Ischaemic

heart

disease

Stroke

Colorectal

cancer

Breast

cancer

Other

40%

34%

11%

5%

4% 7%

81

0

20

40

Rate 1,000

0 20 40 60 80 100

Age

Males

Females

Figure 4.6: Burden (DALYs) attributable to high body mass by age expressed as: (a) rates by sex,

and (b) numbers by specific cause, Australia, 2003

Physical inactivity

Physical inactivity was responsible for 6.6% of the total burden of disease and injury in

Australia in 2003 (Table 4.7), with ischaemic heart disease, Type 2 diabetes and stroke

accounting for more than four-fifths of this burden. Overall, the burden from physical

inactivity was shared equally between the sexes. With the exception of diabetes, most of the

conditions attributable to physical inactivity were associated with high mortality (Figure 4.7).

The rate of burden from physical inactivity per head of population increased with age and

the absolute burden was concentrated around old age. The contributions from ischaemic

heart disease and Type 2 diabetes dominated across all ages (Figure 4.8).

Table 4.7: Deaths and burden (DALYs) attributable to physical inactivity by specific cause,

Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Ischaemic heart disease 8,739 6.6 88,617 3.4

Type 2 diabetes 704 0.5 34,132 1.3

Stroke 2,390 1.8 23,742 0.9

Colorectal cancer 1,074 0.8 14,978 0.6

Breast cancer 584 0.4 12,962 0.5

Total attributable 13,491 10.2 174,431 6.6

per 0

10

20

30

Number (thousands)

0 20 40 60 80 100

Age

Other

Breast cancer

Colorectal cancer

Stroke

Ischaemic heart disease

Type 2 diabetes

82

Total

IHD

Colorectal cancer

Type 2 diabetes

Stroke

Breast cancer

50%

58%

54%

53%

43%

0%

50%

42%

46%

47%

57%

100%

Males Females

Total

IHD

Colorectal cancer

Stroke

Breast cancer

Type 2 diabetes

67%

82%

81%

69%

66%

19%

33%

18%

19%

31%

34%

81%

Fatal Non-fatal

Figure 4.7: Burden (DALYs) attributable to physical inactivity by specific cause expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal

outcomes, Australia, 2003

0

50

100

1,000

0 20 40 60 80 100

Age

Males

Females

Figure 4.8: Burden (DALYs) attributable to physical inactivity by age expressed as: (a) rates by

sex, and (b) numbers by specific cause, Australia, 2003

Rate per Ischaemic

heart

disease

Type 2

diabetes

Stroke

Colorectal

cancer

Breast

cancer

51%

20%

14%

9%

7%

0

10

20

Number (thousands)

0 20 40 60 80 100

Age

Breast cancer

Colorectal cancer

Stroke

Type 2 diabetes

Ischaemic heart disease

83

High blood cholesterol

High blood cholesterol was responsible for 6.2% the total burden of disease and injury in

Australia in 2003 (Table 4.8), with ischaemic heart disease and stroke accounting for this

entire burden. Both ischaemic heart disease and stroke were associated with high mortality.

Overall, males experienced a slightly higher burden from high blood cholesterol than

females (Figure 4.9).

The rate of burden from high blood cholesterol per head of population increased with age

and the absolute burden was concentrated around old age. The contribution from ischaemic

heart disease dominated across all ages (Figure 4.10).

Table 4.8: Deaths and burden (DALYs) attributable to high blood cholesterol by specific cause,

Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Ischaemic heart disease 13,371 10.1 138,605 5.3

Stroke 1,980 1.5 24,986 0.9

Total attributable 15,351 11.6 163,591 6.2

Ischaemic

heart

disease

Stroke

85%

15% Total

IHD

Stroke

55%

56%

46%

45%

44%

54%

Males Females

Total

IHD

Stroke

79%

82%

64%

21%

18%

36%

Fatal Non-fatal

Figure 4.9: Burden (DALYs) attributable to high blood cholesterol by specific cause expressed

as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal

outcomes, Australia, 2003

84

Number Figure 4.10: Burden (DALYs) attributable to high blood cholesterol by age expressed as: (a) rates

by sex, and (b) numbers by specific cause, Australia, 2003

Alcohol

Alcohol has both hazardous and protective effects on health, and the age and sex distribution

of these effects varies in important ways. Of the 14 risk factors examined, alcohol was

responsible for the greatest amount of burden in males under the age of 45 (Table 4.3).

Alcohol harm was responsible for 3.2% of the total burden of disease and injury in Australia

in 2003. Alcohol also prevented 0.9% per cent of the total burden in 2003 (Table 4.9). The

benefits of alcohol consumption outweigh its harmful effects only in females over the age of

65. Given that the net impact of alcohol was to contribute to 2.3% of total burden, it is

important to understand that, even though moderate intake of alcohol may have beneficial

effects at middle and older ages, alcohol is harmful when taken in excess at all ages.

Alcohol abuse, road traffic accidents and suicide contributed two-thirds of the harm

attributed to alcohol (Figure 4.11).

This study reports a substantially lower health benefit due to alcohol compared to the

previous Australian burden study (AIHW: Mathers et al. 1999, AIHW: Ridolfo & Stevenson

2001) with only an estimated 2,346 deaths being prevented in 2003 compared to 7,157 deaths

in 1996. This is due to the previous study underestimating the number of people who abstain

from alcohol or drink less than 0.25 drinks per day.

0

50

100

Rate per 1,000

0 20 40 60 80 100

Age

Males

Females

0

10

20

(thousands)

0 20 40 60 80 100

Age

Stroke

Ischaemic heart disease

85

Table 4.9: Deaths and burden (DALYs) attributable to alcohol by specific cause, Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Harm

Alcohol abuse 918 0.7 34,116 1.3

Suicide & self-inflicted injuries 553 0.4 12,245 0.5

Road traffic accidents 396 0.3 11,121 0.4

Oesophagus cancer 368 0.3 4,594 0.2

Breast cancer 184 0.1 4,152 0.2

Other 1,012 0.8 19,207 0.7

Total attributable harm 3,430 2.6 85,435 3.2

Benefit

Ischaemic heart disease –1,950 –1.5 –20,659 –0.8

Stroke –380 –0.3 –3,451 –0.1

Other –16 0.0 –233 0.0

Total attributable benefit –2,346 –1.8 –24,343 –0.9

Total attributable 1,084 0.8 61,091 2.3

Alcohol

dependence

Suicide &

self-inflicted

Road

traffic

accidents

Oesophagus

cancer

Breast

cancer

Other

39%

13% 14%

5%

5%

25%

Total

Road traffic accidents

Suicide & self-inflicted

Alcohol dependence

Oesophagus cancer

Breast cancer

76%

89%

83%

80%

79%

0%

24%

11%

17%

20%

21%

100%

Males Females

Total

Suicide & self-inflicted

Oesophagus cancer

Road traffic accidents

Breast cancer

Alcohol dependence

66%

99%

94%

88%

65%

42%

34%

1%

6%

12%

35%

58%

Fatal Non-fatal

Figure 4.11: Burden (DALYs) attributable to alcohol (alcohol harm) by specific cause expressed

as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and non-fatal

outcomes, Australia, 2003

86

0

5

10

0 20 40 60 80 100

Age

Males

Females

0

5

10

Number 0 20 40 60 80 100

Age

Other

Breast cancer

Oesophagus cancer

Road traffic accidents

Suicide & self-inflicted

Alcohol dependence

Figure 4.12: Burden (DALYs) attributable to alcohol (alcohol harm) by age expressed as: (a) rates

by sex, and (b) numbers by specific cause, Australia, 2003

Ischaemic

heart

disease

Stroke

Other

77%

22%

1% Total

IHD

Stroke

56%

72%

0%

44%

28%

100%

Males Females

Total

IHD

Stroke

79%

83%

66%

21%

17%

34%

Fatal Non-fatal

Figure 4.13: Burden (DALYs) prevented due to alcohol (alcohol benefit) by specific cause

expressed as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to

fatal and non-fatal outcomes, Australia, 2003

Rate per 1,000

(thousands)

87

Rate per 1,000

Figure 4.14: Burden (DALYs) attributable to alcohol (alcohol benefit) by age expressed as:

(a) rates by sex, and (b) numbers by specific cause, Australia, 2003

Low fruit and vegetable consumption

Low fruit and vegetable consumption was responsible for 2.1% of the total burden of disease

and injury in Australia in 2003 (Table 4.10). Eating enough fruit and vegetables helps to

prevent cancers, ischaemic heart disease and, to a lesser extent, stroke. Sixty-nine per cent of

the burden from low fruit and vegetable consumption was due to ischaemic heart disease

and two-thirds was experienced by males, partly because males tend to eat less fruit and

vegetables than females, but also because males have a higher burden from ischaemic heart

disease than females. Overall, 81%of the burden from low fruit and vegetable consumption

was due to mortality.

The absolute burden from low fruit and vegetable consumption peaked between the age of

60 and 80 while the rate per head of population continued to increase until old age. The

contribution from ischaemic heart disease dominated at all ages (Figure 4.16).

Table 4.10: Deaths and burden (DALYs) attributable to low fruit and vegetable consumption by

specific cause, Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Ischaemic heart disease 3,219 2.4 37,981 1.4

Stroke 605 0.5 7,346 0.3

Lung cancer 463 0.3 5,956 0.2

Other 281 0.2 3,977 0.2

Total attributable 4,568 3.5 55,259 2.1

0

10

20

0 20 40 60 80 100

Age

Males

Females

0

2

4

Number (thousands)

0 20 40 60 80 100

Age

Other

Stroke

Ischaemic heart disease

88

Ischaemic

heart

disease

Stroke

Lung

cancer

Stomach

cancer

Other

69%

13%

11%

3%4% Total

Lung cancer

IHD

Stomach cancer

Stroke

66%

68%

68%

66%

54%

34%

32%

32%

34%

46%

Males Females

Total

Lung cancer

Stomach cancer

IHD

Stroke

81%

93%

91%

82%

64%

19%

7%

9%

18%

36%

Fatal Non-fatal

Figure 4.15: Burden (DALYs) attributable to low fruit and vegetable consumption by specific

cause expressed as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to

fatal and non-fatal outcomes, Australia, 2003

0

10

20

Rate per 1,000

0 20 40 60 80 100

Age

Males

Females

0

5

10

Number (thousands)

0 20 40 60 80 100

Age

Other

Stomach cancer

Lung cancer

Stroke

Ischaemic heart disease

Figure 4.16: Burden (DALYs) attributable to low fruit and vegetable consumption by age

expressed as: (a) rates by sex , and (b) numbers by specific cause, Australia, 2003

Illicit drugs

Illicit drugs were responsible for 2.0% of the total burden of disease and injury in Australia

in 2003 (Table 4.11). Illicit drugs are a direct cause of death and disability as well as being

89

risk factors for conditions such as HIV/AIDS, hepatitis, low birth weight, inflammatory

heart disease, poisoning, and suicide and self-inflicted injuries. Almost three-quarters of the

burden from illicit drugs was experienced by males because males are more likely to both

use illicit drugs and adopt drug habits that put them at risk of dying. Overall, fifty-seven per

cent of the burden from illicit drugs was due to mortality (Figure 4.17).

The burden from illicit drugs, both in terms of rate per head of population and in absolute

terms, peaked in early adulthood when drug addiction usually begins. The contribution

from heroin dominated at this age but was overtaken by contributions from hepatitis B and

C with increasing age as the long-term effects of drug use begin to manifest (Figure 4.18).

Table 4.11: Deaths and burden (DALYs) attributable to illicit drugs by specific cause, Australia,

2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Heroin & polydrug abuse 263 0.2 16,758 0.6

Hepatitis C 759 0.6 11,709 0.4

Cannabis abuse 0 0.0 5,206 0.2

Suicide & self-inflicted injuries 204 0.2 4,458 0.2

Hepatitis B 329 0.2 3,637 0.1

Benzodiazepine abuse 1 0.0 2,656 0.1

Other 149 0.1 7,040 0.3

Total attributable 1,705 1.3 51,463 2.0

Total

Cannabis

Suicide & self-inflicted

Heroin

Hepatitis C

Hepatitis B

Benzodiazepine

71%

78%

78%

74%

68%

64%

42%

29%

22%

22%

26%

32%

36%

58%

Males Females

Total

Suicide & self-inflicted

Hepatitis C

Hepatitis B

Heroin

Benzodiazepine

Cannabis

57%

99%

97%

97%

39%

1%

0%

43%

1%

3%

3%

61%

99%

100%

Fatal Non-fatal

Figure 4.17: Burden (DALYs) attributable to illicit drugs by specific cause expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and nonfatal

outcomes, Australia, 2003

Heroin

Hepatitis C

Cannabis

Suicide &

self-inflicted

Hepatitis B

Benzodiazepine

Other

33%

23%

10%

9%

7%

5%

14%

90

0

5

10

0 20 40 60 80 100

Age

Males

Females

Number thousands)

Figure 4.18: Burden (DALYs) attributable to illicit drugs by age expressed as: (a) rates by sex, and

(b) numbers by specific cause, Australia, 2003

Occupational exposures and hazards

Occupational exposures and hazards were responsible for 2.0% of the total burden of disease

and injury in Australia in 2003 (Table 4.12). More than two-thirds of this burden was

experienced by males, mostly because occupational exposures and hazards occur in

industries dominated by male employment. Females, however, experienced 86% of the

burden from occupational overuse syndrome (OOS). Overall, 43% of the burden from

occupational exposures and hazards was due to mortality (Figure 4.19).

The burden from occupational exposures and hazards was concentrated in the working ages

and peaked in middle age, both in terms of rate per head of population and in absolute terms

(Figure 4.20).

Table 4.12: Deaths and burden (DALYs) attributable to occupational exposures and hazards by

specific cause, Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Cancer 1,154 0.9 15,559 0.6

Back pain 1 0.0 7,806 0.3

Occupational overuse syndrome — — 4,944 0.2

COPD 111 0.1 4,563 0.2

Road traffic accidents 124 0.1 2,975 0.1

Other 264 0.2 15,515 0.6

Total attributable 1,654 1.3 51,362 2.0

Rate per 1,000

0

5

10

(0 20 40 60 80 100

Age

Other

Benzodiazepine dependence

Hepatitis B

Suicide & self-inflicted

Cannabis dependence

Hepatitis C

Heroin dependence

91

Cancer

Back pain

Occupational

overuse

syndrome

COPD

Road

traffic

accidents

Other

30%

15%

10%

9%

6%

30%

Total

COPD

Road traffic accidents

Cancer

Back pain

OOS

69%

91%

89%

76%

58%

14%

31%

9%

11%

24%

42%

86%

Males Females

Total

Road traffic accidents

Cancer

COPD

Back pain

OOS

43%

98%

83%

27%

0%

0%

57%

2%

17%

73%

100%

100%

Fatal Non-fatal

Figure 4.19: Burden (DALYs) attributable to occupational exposures and hazards by specific

cause expressed as: (a) proportions of total, (b) proportions by sex, and (c) proportions due

to fatal and non-fatal outcomes, Australia, 2003

0

5

10

0 20 40 60 80 100

Age

Males

Females

0

5

10

Number (thousands)

0 20 40 60 80 100

Age

Other

Road traffic accidents

COPD

Occupational overuse syndrome

Back pain

Cancer

Figure 4.20: Burden (DALYs) attributable to occupational exposures and hazards by age

expressed as: (a) rates by sex, and (b) numbers by specific cause, Australia, 2003

Rate per 1,000

92

Intimate partner violence

The attribution of burden to intimate partner violence was attempted only for females due to

insufficient evidence on prevalence and risk among males. While this risk is unlikely to be

zero, it is probably small in comparison with the risk experienced by females. Intimate

partner violence was responsible for 1.1% of the total burden of disease and injury in

Australia in 2003 (Table 4.13). Of the 14 risk factors examined, intimate partner violence

contributed most to the burden in females under the age of 45 (Table 4.3). Most of the burden

from intimate partner violence was due to anxiety and depression, and conditions arising

due to the associated increased use of tobacco, alcohol and illicit substances (Figure 4.21).

The burden from intimate partner violence, both in terms of rate per head of population and

in absolute terms, peaked at around age 30 then declined with age (Figure 4.22). The

contribution from anxiety and depression dominated throughout adulthood but was

overtaken by contributions from tobacco-related disease with increasing age as the effects of

higher smoking rates begin to manifest.

Table 4.13: Deaths and burden (DALYs) for females attributable to intimate partner violence by

specific cause, Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Anxiety & depression 3 0.0 18,358 0.7

Suicide & self-inflicted injuries 131 0.1 3,099 0.1

Lung cancer 89 0.1 1,477 0.1

Homicide & violence 35 0.0 1,260 0.0

COPD 49 0.0 1,114 0.0

Other 128 0.1 4,051 0.2

Total attributable 435 0.3 29,360 1.1

93

Total

Anxiety & depression

Suicide & self-inflicted

Lung cancer

Homicide & violence

COPD

0%

0%

0%

0%

0%

0%

100%

100%

100%

100%

100%

100%

Males Females

Total

Suicide & self-inflicted

Lung cancer

Homicide & violence

COPD

Anxiety & depression

27%

98%

93%

63%

49%

0%

73%

2%

7%

37%

51%

100%

Fatal Non-fatal

Figure 4.21: Burden (DALYs) attributable to intimate partner violence by specific cause

expressed as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to

fatal and non-fatal outcomes, Australia, 2003

0

2

4

6

per 1,000

0 20 40 60 80 100

Age

Males

Females

(thousands)

0 20 40 60 80 100

Age

Other

COPD

Homicide & violence

Lung cancer

Suicide & self-inflicted

Anxiety & depression

Figure 4.22: Burden (DALYs) attributable to intimate partner violence by age expressed as:

(a) rates by sex, and (b) numbers by specific cause, Australia, 2003

Child sexual abuse

Child sexual abuse was responsible for 0.9% of the total burden of disease and injury in

Australia in 2003 (Table 4.14). Ninety-four per cent of this burden was due to anxiety and

depression

Anxiety &

Suicide & depression

self-inflicted

Lung

cancer

Homicide &

violence

COPD

Other

11% 63%

5%

4%

4%

14%

Rate 0

2

4

Number

94

depression, suicide and self-inflicted injuries, and alcohol abuse. Of the 14 risk factors

examined, child sexual abuse was the second leading cause of burden in females under the

age of 45 (Table 4.3). Just over four-fifths of the burden from child sexual abuse was

experienced by females and 14% was due to mortality (Figure 4.23).

The burden from child sexual abuse, both in terms of rate per head of population and in

absolute terms, peaked at around 40 years-old then declined with age. The contribution from

anxiety and depression dominated at this age after which contributions from suicide and

self-inflicted injuries and alcohol abuse became increasingly important (Figure 4.24).

Table 4.14: Deaths and burden (DALYs) attributable to child sexual abuse by specific cause,

Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Anxiety and depression 7 0.0 19,133 0.7

Suicide & self-inflicted injuries 103 0.1 2,258 0.1

Alcohol abuse 24 0.0 730 0.0

Other 62 0.0 1,392 0.1

Total attributable 196 0.1 23,513 0.9

Total

Alcohol dependence

Suicide & self-inflicted

Anxiety & depression

18%

59%

45%

11%

82%

41%

55%

89%

Males Females

Total

Suicide & self-inflicted

Alcohol dependence

Anxiety & depression

15%

98%

54%

0%

85%

2%

46%

100%

Fatal Non-fatal

Figure 4.23: Burden (DALYs) attributable to child sexual abuse by specific cause expressed

as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and nonfatal

outcomes, Australia, 2003

Anxiety &

depression

Suicide &

self-inflicted

Alcohol

dependence

Other

81%

10%

3% 6%

95

0

2

4

0 20 40 60 80 100

Age

Males

Females

Figure 4.24: Burden (DALYs) attributable to child sexual abuse by age expressed as: (a) rates by

sex, and (b) numbers by specific cause, Australia, 2003

Urban air pollution

The health effects of urban air pollution are largely chronic conditions (such as ischaemic

heart disease, lung cancer and stroke) resulting from long-term exposure to this risk. There

may also be an additional burden from short-term exposure to abnormally high levels of

urban air pollution, although this risk is more controversial. Table 4.15 provides estimates for

both long-term and short-term effects; all other figures in this section reflect the long-term

effects only. Urban air pollution was responsible for 1.0% of the total burden of disease and

injury in Australia in 2003 (Table 4.15). Sixty-two per cent of the burden from urban air

pollution was due to cardiovascular disease (ischaemic heart disease and stroke) and 53% of

the burden from urban air pollution was experienced by males. Overall, 80% of the burden

from urban air pollution was due to mortality (Figure 4.25).

The absolute burden from urban air pollution peaked at age 80 while the rate per head of

population continued to increase until old age. The contribution from cardiovascular disease

dominated at all ages (Figure 4.26).

Rate per 1,000

0

2

4

Number (thousands)

0 20 40 60 80 100

Age

Other

Alcohol dependence

Suicide & self-inflicted

Anxiety & depression

96

Table 4.15: Deaths and burden (DALYs) attributable to urban air pollution by specific cause, Australia,

2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Long-term

Ischaemic heart disease 959 0.7 8,483 0.3

Lung cancer 351 0.3 4,115 0.2

Stroke 432 0.3 3,738 0.1

COPD 184 0.1 2,654 0.1

Other 83 0.1 748 0.0

Total attributable to long-term

exposure

2,009 1.5 19,738 0.7

Short-term

Total attributable to short-term

exposure

1,046 0.8 7,781 0.3

Total attributable 3,056 2.3 27,519 1.0

97

Ischaemic

heart

disease

Lung

cancer

Stroke

COPD

Other

43%

21%

19%

13%

4% Total

Lung cancer

COPD

IHD

Stroke

53%

59%

55%

54%

41%

47%

41%

45%

46%

59%

Males Females

Total

Lung cancer

IHD

Stroke

COPD

80%

93%

83%

75%

55%

20%

7%

17%

25%

45%

Fatal Non-fatal

Figure 4.25: Burden (DALYs) attributable to urban air pollution (long-term effects) by specific

cause expressed as: (a) proportions of total, (b) proportions by sex, and (c) proportions due to

fatal and non-fatal outcomes, Australia, 2003

0

5

10

15

0 20 40 60 80 100

Age

Males

Females

0

1

2

3

Number (thousands)

0 20 40 60 80 100

Age

Other

COPD

Stroke

Lung cancer

Ischaemic heart disease

Figure 4.26: Burden (DALYs) attributable to urban air pollution (long-term effects) by age

expressed as: (a) rates by sex, and (b) numbers by specific cause, Australia, 2003

Rate per 1,000

98

Unsafe sex

Unsafe sex was responsible for 0.6% of the total burden of disease and injury in Australia in

2003 (Table 4.16). Over two-thirds of this burden was due to cervix cancer and HIV/AIDS.

Sixty-three per cent of the burden from unsafe sex was due to mortality (Figure 4.27).

The burden from unsafe sex in males peaked in early adulthood due to the impact of HIV

infection, after which it declined and the long-term effects of hepatitis B infection began to

manifest. In females, the rate per head of population continued to increase with age and the

absolute burden was concentrated around middle age when the contribution from cervix

cancer dominated (Figure 4.28).

Table 4.16: Deaths and burden (DALYs) attributable to unsafe sex by specific cause, Australia, 2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Cervix cancer 298 0.2 5,231 0.2

HIV/AIDS 105 0.1 4,873 0.2

Hepatitis B 225 0.2 2,499 0.1

Other 26 0.0 2,293 0.1

Total attributable 655 0.5 14,897 0.6

Cervix

cancer

HIV/AIDS

Hepatitis B

Other

35%

33%

17%

15% Total

HIV/AIDS

Hepatitis B

Cervix cancer

42%

93%

61%

0%

58%

7%

39%

100%

Males Females

Total

Hepatitis B

Cervix cancer

HIV/AIDS

63%

96%

83%

45%

37%

4%

17%

55%

Fatal Non-fatal

Figure 4.27: Burden (DALYs) attributable to unsafe sex by specific cause expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and nonfatal

outcomes, Australia, 2003

99

0

1

2

Rate per 0 20 40 60 80 100

Age

Males

Females

0

1

2

0 20 40 60 80 100

Age

Other

Hepatitis B

HIV/AIDS

Cervix cancer

Figure 4.28: Burden (DALYs) attributable to unsafe sex by age expressed as: (a) rates by sex, and

(b) numbers by specific cause, Australia, 2003

Osteoporosis

Osteoporosis was responsible for 0.2% of the total burden of disease and injury in Australia

in 2003 (Table 4.17). Almost all of this burden was due to falls and more than three-quarters

was experienced by females. More than half of the burden from osteoporosis was due to

mortality (Figure 4.29).

The burden from osteoporosis was experienced from age 60 onwards. The contribution from

falls dominated at all ages (Figure 4.30).

Table 4.17: Deaths and burden (DALYs) attributable to osteoporosis by specific cause, Australia,

2003

Deaths DALYs

Specific cause Number Per cent of total Number Per cent of total

Falls 534 0.4 4,329 0.2

Other 10 0.0 58 0.0

Total attributable 545 0.4 4,386 0.2

1,000

Number (thousands)

100

Falls

Other

99%

1% Total

Falls

23%

23%

77%

77%

Males Females

Total

Falls

57%

56%

43%

44%

Fatal Non-fatal

Figure 4.29: Burden (DALYs) attributable to osteoporosis by specific cause expressed as:

(a) proportions of total, (b) proportions by sex, and (c) proportions due to fatal and nonfatal

outcomes, Australia, 2003

0

5

10

15

per 0 20 40 60 80 100

Age

Males

Females

0

1

1

2

0 20 40 60 80 100

Age

Other

Falls

Figure 4.30: Burden (DALYs) attributable to osteoporosis by age expressed as: (a) rates by sex,

and (b) numbers by specific cause, Australia, 2003

Rate 1,000

Number (thousands)

101

5 Differentials in burden of disease and

injury across Australia

5.1 Overview

This chapter describes differentials in burden of disease and injury across Australia in terms

of the following stratifications of the population: state and territory jurisdictions,

socioeconomic quintiles and remoteness categories (major cities, regional and remote). The

chapter begins by comparing life expectancy and health-adjusted life expectancy (HALE)

across each subpopulation within these strata. It then discusses the main differentials

between subpopulations by leading causes of burden. Table 5.1 summarises for each

subpopulation the important demographic characteristics that influence these differentials.

Table 5.1: Selected demographic characteristics by area, Australia, 2003

Population(a) Per cent of population for area

Age group (years)

Area (’000)

Per cent

of

Australia <15 15–59 60–79 80+ Males Indigenous(b) Low SES(c)

Jurisdiction

NSW 6,687.5 33.6 19.9 62.4 14.2 3.5 49.7 2.0 19.0

Vic 4,918.0 24.7 19.5 62.9 14.1 3.4 49.3 0.6 16.0

Qld 3,797.3 19.1 20.8 62.9 13.3 3.0 49.9 3.3 23.9

WA 1,952.5 9.8 20.4 64.0 12.8 2.8 50.0 3.3 22.5

SA 1,527.6 7.7 18.8 61.7 15.4 4.1 49.5 1.6 14.9

Tas 477.2 2.4 20.4 60.6 15.4 3.7 49.3 3.6 55.4

ACT 322.9 1.6 19.8 67.4 10.7 2.2 49.4 1.2 0.3

NT 198.4 1.0 25.4 67.4 6.5 0.7 52.5 28.8 28.4

Socioeconomic quintile

Low 3,917.1 19.7 21.9 61.5 13.7 2.9 50.0 n.a. n.a.

Mod. low 3,973.8 20.0 21.2 60.6 14.9 3.3 49.8 n.a. n.a.

Average 3,747.8 18.8 20.3 61.9 14.3 3.4 49.8 n.a. n.a.

Mod. high 4,097.3 20.6 19.4 64.5 13.0 3.1 49.6 n.a. n.a.

High 4,145.4 20.8 17.4 65.4 13.5 3.7 49.1 n.a. n.a.

Remoteness

Major cities 13,347.9 66.8 19.1 64.4 13.5 3.3 49.6 1.0 17.2

Regional 6,050.5 30.4 21.7 59.7 15.3 3.4 50.0 3.2 23.7

Remote 483.1 2.4 25.6 63.4 9.2 1.8 53.2 25.7 39.2

Australia 19,894.7 100.0 20.0 62.8 13.9 3.3 49.6 2.3 19.7

(a) Estimated resident population figures as at 30 June 2003 (ABS cat. no. 3201.0).

(b) Based on people identifying as Indigenous in the 2001 Census (ABS cat. no. 2019.0 – 2019.8).

(c) Based on Socio-Economic Indexes for Areas (SEIFA) (ABS cat. no. 2039.0.55.001).

102

5.2 Health-adjusted life expectancy

HALE provides an estimate of the average years of equivalent ‘healthy’ life that a person can

expect to live at various ages. HALE is related to life expectancy, which provides an estimate

of the average years of life a person can expect to live at various ages given current risks of

mortality. HALE extends this concept by reducing the estimated duration by the proportion

of time spend at each age in states less than perfect health, adjusted for the relative severity

of those health states. The sum of prevalent years lost due to disability (PYLD) across all

causes is used to derive this ‘severity-weighted’ proportion for each age. Since the starting

point for HALE is a life table, life expectancy at birth for the various subpopulations

discussed in this chapter is presented first in Table 5.2.

Table 5.2: Life expectancy at birth by area and sex, Australia, 2003

Life expectancy at birth (years)

Area Males Females Persons

Jurisdiction

NSW 78.2 (78.0–78.3) 83.1 (83.0–83.3) 80.6 (80.5–80.8)

Vic 78.6 (78.4–78.8) 83.2 (83.0–83.4) 80.9 (80.8–81.0)

Qld 78.4 (78.2–78.6) 83.3 (83.1–83.5) 80.8 (80.7–81.0)

WA 79.0 (78.7–79.3) 83.7 (83.4–84.0) 81.3 (81.1–81.5)

SA 77.7 (77.3–78.0) 82.9 (82.5–83.2) 80.3 (80.0–80.5)

Tas 76.7 (76.1–77.3) 81.7 (81.1–82.2) 79.2 (78.8–79.6)

ACT 80.2 (79.4–80.9) 84.2 (83.4–84.9) 82.3 (81.7–82.8)

NT 73.1 (72.2–74.0) 78.6 (77.6–79.6) 75.5 (74.8–76.1)

Socioeconomic quintile

Low 76.9 (76.7–77.1) 82.3 (82.1–82.5) 79.6 (79.4–79.7)

Moderately low 77.4 (77.2–77.6) 82.8 (82.6–83.0) 80.0 (79.9–80.2)

Average 77.7 (77.5–77.9) 82.7 (82.5–82.9) 80.2 (80.0–80.3)

Moderately high 79.0 (78.8–79.2) 83.5 (83.3–83.7) 81.2 (81.1–81.4)

High 80.9 (80.6–81.1) 84.5 (84.3–84.7) 82.7 (82.5–82.8)

Remoteness

Major cities 78.8 (78.7–78.9) 83.5 (83.4–83.6) 81.2 (81.1–81.2)

Regional 77.5 (77.4–77.7) 82.7 (82.5–82.8) 80.0 (79.9–80.1)

Remote 75.4 (74.8–76.1) 81.5 (80.9–82.2) 78.1 (77.6–78.6)

Australia 78.3 (78.2–78.4) 83.2 (83.1–83.3) 80.7 (80.7–80.8)

When interpreting the results presented in this chapter it is important to keep in mind that

Indigenous people are a much greater proportion of the total population in the Northern

Territory and remote areas of Australia. This accounts for the much greater health loss in

these areas, although the contribution of Indigenous populations to this loss is not quantified

in this report. Readers seeking such comparisons are referred to the separate report on the

Indigenous component of this study. Once the Indigenous results are available separate

small area comparisons can be made for non-Indigenous people. This is relevant to health

103

policy in that there is a raft of Indigenous health issues that is distinct from the health issues

of the general population living in remote areas.

HALE was calculated for subpopulations using the PYLD estimated for each population

separately, as discussed in Chapter 2. Total HALE at birth across Australia in 2003 was

70.6 years for males, 75.2 years for females and 72.9 years for both sexes combined (Table

5.3). The figures for both sexes ranged from 67.7 to 75.9 years across state and territory

jurisdictions, 71.2 to 75.5 years across socioeconomic quintiles and 69.5 to 73.5 years across

remoteness categories.

Table 5.3: Health-adjusted life expectancy (HALE) and life expectancy at birth lost due to disability

by area and sex, Australia, 2003

Health-adjusted life expectancy (HALE) (years)

At birth At age 60

Life expectancy

at birth

lost due to disability (%)

Area Males Females Persons Males Females Persons Males Females Persons

Jurisdiction

NSW 70.5 75.3 72.9 17.1 20.6 18.9 9.8 9.5 9.6

Vic 71.1 75.4 73.2 17.5 20.8 19.2 9.6 9.4 9.5

Qld 70.5 75.3 72.8 17.0 20.4 18.7 10.1 9.7 9.9

WA 71.5 75.6 73.5 17.5 20.6 19.1 9.6 9.6 9.6

SA 69.3 74.2 71.7 16.4 20.0 18.3 10.8 10.5 10.6

Tas 68.8 73.7 71.3 16.3 19.7 18.1 10.2 9.8 10.0

NT 65.8 70.2 67.7 12.6 15.1 13.6 10.0 10.6 10.3

ACT 73.9 77.8 75.9 18.9 21.9 20.5 7.8 7.5 7.7

Socioeconomic quintile

Low 68.7 73.8 71.2 16.1 19.7 17.9 10.7 10.4 10.6

Moderately

low 69.5 74.6 72.0 16.4 20.1 18.2 10.2 9.9 10.1

Average 69.9 74.6 72.2 16.6 20.1 18.4 10.0 9.8 9.9

Moderately

high 71.4 75.9 73.6 17.6 20.8 19.3 9.7 9.1 9.4

High 73.8 77.2 75.5 19.2 21.9 20.6 8.7 8.7 8.7

Remoteness

Major cities 71.3 75.6 73.5 17.5 20.8 19.2 9.6 9.4 9.5

Regional 69.6 74.5 72.0 16.5 20.1 18.3 10.3 9.8 10.1

Remote 67.3 72.3 69.5 15.4 18.5 16.8 10.8 11.3 11.0

Australia 70.6 75.2 72.9 17.1 20.5 18.9 9.8 9.6 9.7

104

When the difference between life expectancy and HALE is expressed as a proportion of life

expectancy, this represents the proportion of remaining life that is lost due to disability.

Hereafter this is referred to as PLD (proportion of life expectancy lost due to disability). PLD

at birth is the most commonly reported figure, although it can be calculated at any age and

increases with age (Figure 5.1).

0

50

100

0 50 100 0 50 100

Males Females

Remaining years lost due to disability Remaining years of healthy life

Percent

Age

Figure 5.1: Proportion of life expectancy lost due to disability (%) by age and sex, Australia, 2003

This report shows for the first time that there are differentials in PLD at birth across

Australia (Table 5.3). There was a strong socioeconomic gradient in this measure, with the

lowest socioeconomic quintile losing 10.6% of life expectancy at birth through disability and

the highest losing only 8.7%. Differentials with respect to remoteness category were also

apparent but not as large, with remote areas losing 11.0% and major cities losing 9.5%. With

respect to state and territory jurisdictions, the Australian Capital Territory had the lowest

PLD at birth at 7.7% and South Australia had the highest at 10.6%.

105

NSW

Vic Qld

SA

WA

Tas

NT

ACT

Low

Average Mod low

Mod high

High

Major cities

Regional

Remote

76

78

80

82

76

78

80

82

76

78

80

82

8 9 10 11 8 9 10 11 8 9 10 11

State/Territory SES quintile Remoteness

Life expectancy at birth (years)

Proportion of life expectancy at birth lost due to disability (%)

Figure 5.2: Life expectancy at birth (years) versus proportion of life expectancy at birth lost due

to disability (%) by area, Australia, 2003

Figure 5.2 shows the inverse relationship between life expectancy at birth and PLD, with

subpopulations experiencing the highest life expectancy also having the lowest PLD. In other

words, longevity is associated with lower average levels of disability throughout the life

span.

The remainder of this chapter presents health differentials across these subpopulations using

the standard burden metric of disability-adjusted life years—(DALYs). All rates per head of

population were standardised to remove the effect of different age structures between

populations. This standard technique is used when comparing populations whereby the agespecific

rates of the populations of interest are applied to the age structure of a reference

population before comparisons are made.

5.3 State and territory differentials

The proportion of burden experienced by each state and territory jurisdiction was roughly

proportional to the population size, with New South Wales accounting for the largest

proportion (34.0%), followed by Victoria (24.8%) and Queensland (18.6%) (Table 5.4). Males

experienced more of this burden than females in all jurisdictions except the Australian

Capital Territory where it was more equally distributed between the sexes. In all

jurisdictions except Tasmania, slightly more of total burden was due to non-fatal causes.

106

Table 5.4: Burden (DALYs) for state/territory jurisdictions by proportions of total, proportions by

sex and proportions due to mortality, Australia, 2003

Area DALYs (’000) Per cent of total Per cent male Per cent fatal burden

NSW 895.8 34.0 51.9 49.5

Vic 651.6 24.8 50.9 48.9

Qld 488.5 18.6 53.0 46.9

SA 234.3 8.9 51.5 48.7

WA 236.8 9.0 51.7 46.6

Tas 73.4 2.8 51.6 51.4

NT 22.9 0.9 58.5 46.6

ACT 29.5 1.1 50.4 47.5

Australia 2,632.8 100.0 51.8 48.6

There were important differentials in burden experienced per head of population between

jurisdictions. After age standardisation, the Northern Territory had almost twice the rate of

total burden of the Australian Capital Territory for both males and females. This was due to

higher rates of burden for most causes, but particularly for cardiovascular disease, diabetes

and injuries (Figure 5.3).

0

50

100

150

200

NT Tas SA Qld NSW Vic WA ACT NT Tas SA Vic NSW Qld WA ACT

Males Females

Cancer Cardiovascular Chronic respiratory Diabetes

Injuries Mental Neurological Other

Rate per 1,000

Figure 5.3: Age-standardised DALY rates per 1,000 by state/territory jurisdiction, broad cause

group and sex, Australia, 2003

Table 5.5 provides a comparison between burden rates for jurisdictions and the national

average for the 10 leading broad causes of burden in Australia for 2003. Of these causes, the

greatest difference between jurisdictions with the lowest and highest rates occurred (in order

of magnitude of difference) in diabetes, injuries, genitourinary conditions and chronic

respiratory diseases. The causes that contributed most in terms of the absolute difference

107

observed between jurisdictions were cardiovascular disease (19.7%), diabetes (15.5%) and

injuries (13.6% for intentional and unintentional combined).

Table 5.5: Differentials in burden (DALYs) by state/territory jurisdiction for the 10 leading broad

cause groups, Australia, 2003

Rate Standardised rate ratio(b) % diff. % of

Broad cause group Aust.(a) NSW Vic Qld SA WA Tas NT ACT high/low(c) total diff.(d)

Cancer 25.1 1.00 1.02 0.98 1.06 0.96 1.13 1.15 0.87 31.3 6.9

Cardiovascular 23.8 1.04 0.94 1.02 1.09 0.88 1.13 1.61 0.78 104.8 19.7

Mental 17.6 1.03 0.97 1.01 1.06 0.94 1.15 1.05 0.76 52.1 7.0

Neurological 15.7 0.99 0.97 1.00 1.13 1.04 1.02 0.97 0.78 44.3 5.5

Chronic respiratory 9.4 0.99 0.98 0.99 1.20 0.94 1.18 1.72 0.81 111.6 8.6

Diabetes 7.2 0.88 1.15 0.95 1.14 1.00 1.15 2.71 0.57 371.8 15.5

Unintentional injuries 6.3 0.96 0.95 1.08 1.01 1.06 1.13 2.03 0.68 196.7 8.6

Musculoskeletal 5.3 0.96 1.00 1.05 1.02 1.05 1.18 0.96 0.87 35.5 1.7

Genitourinary 3.3 1.01 1.04 0.93 1.06 0.94 1.01 1.76 0.77 127.9 3.3

Intentional injuries 3.0 0.94 0.89 1.11 1.10 1.05 1.18 2.46 0.79 210.3 5.0

All causes 132.4 1.00 0.99 1.00 1.09 0.96 1.12 1.50 0.79 88.7 100.0

(a) DALY rate for Australia per 1,000.

(b) Ratio of age-standardised DALYs per 1,000 population for area to DALYs per 1,000 population for Australia.

(c) Calculated for each cause as the greatest difference in DALY rates between areas as a proportion of lowest rate for that cause.

(d) Calculated for each cause as the greatest difference in DALY rates between areas as a proportion of greatest difference for all causes.

Table 5.6 lists the 10 leading specific causes of burden for Australia and summarises for each

jurisdiction these causes in terms of rank order and percentage of total burden. Diseases of

old age, such as ischaemic heart disease and dementia, contributed less to the total burden in

jurisdictions with younger populations (for example the Northern Territory and the

Australian Capital Territory).

108

Table 5.6: Differentials in burden (DALYs) by state/territory jurisdiction for the 10 leading specific

causes, Australia, 2003

Rank Per cent of total

Specific cause(a) NSW Vic Qld SA WA Tas NT ACT NSW Vic Qld SA WA Tas NT ACT

Ischaemic heart disease 1 1 1 1 1 1 3 2 10.4 9.6 10.2 10.8 8.8 10.7 6.5 8.1

Anxiety & depression 2 2 2 2 2 2 1 1 7.2 7.1 7.9 6.0 8.0 7.3 8.4 9.3

Type 2 diabetes 4 3 3 3 3 3 2 4 4.4 5.9 4.8 5.3 5.4 5.0 7.9 3.5

Stroke 3 4 4 4 5 4 11 3 5.0 4.3 4.4 4.5 3.9 4.4 2.0 3.9

Dementia 5 5 7 5 4 8 15 10 3.8 3.4 3.2 4.0 4.3 2.5 1.2 2.5

Lung cancer 7 6 5 7 6 6 10 7 3.4 3.4 3.3 3.2 3.5 3.8 2.3 2.8

COPD 6 7 6 6 7 5 7 8 3.4 3.1 3.3 3.7 2.8 4.0 3.3 2.6

Adult-onset hearing loss 10 10 8 8 10 9 35 12 2.2 2.5 2.9 2.6 2.4 2.4 0.7 2.3

Colorectal cancer 8 8 10 9 9 7 22 11 2.3 2.6 2.3 2.4 2.5 2.7 0.9 2.4

Asthma 11 9 9 11 8 10 8 5 2.2 2.5 2.5 2.3 2.7 2.4 2.3 3.3

(a) Sorted according to the leading specific causes for Australia.

5.4 Differentials by socioeconomic status

Populations in areas with lower socioeconomic status experienced proportionally more

burden than populations in areas with higher socioeconomic status (Table 5.7). Females

experienced slightly more burden than males in areas with the highest socioeconomic status.

Conversely, males experienced more burden than females in areas with the lowest

socioeconomic status. The highest proportion of burden that was fatal was in the moderately

low and average socioeconomic areas, and the lowest (47.6%) was in the low socioeconomic

area.

Table 5.7: Burden (DALYs) for socioeconomic quintiles by proportions of total, proportions by sex,

and proportions due to mortality, Australia, 2003

Area DALYs (’000) Per cent of total Per cent male Per cent fatal burden

Low SES 562.5 21.4 52.8 47.6

Moderately low SES 564.2 21.4 52.7 49.3

Average SES 523.6 19.9 52.1 49.5

Moderately high SES 507.7 19.3 52.0 48.0

High SES 474.8 18.0 49.1 48.4

Australia 2,632.8 100.0 51.8 48.6

Total burden per head of population increased with decreasing socioeconomic status, with

the most disadvantaged populations having 31.7% greater burden than the most advantaged

populations. Again, this was due to higher rates of burden for most causes, but particularly

for mental disorders and cardiovascular disease (Figure 5.4).

109

0

50

100

150

Low Mod low Average Mod high High Low Mod low Average Mod high High

Males Females

Cancer Cardiovascular Chronic respiratory Diabetes

Injuries Mental Neurological Other

Rate per 1,000

Figure 5.4: Age-standardised DALY rates per 1,000 by socioeconomic quintile, broad cause group

and sex, Australia, 2003

Table 5.8 provides a comparison between burden rates for areas by socioeconomic category

and the national average for the 10 leading broad causes of burden in Australia for 2003. Of

these causes, the greatest difference between areas with the lowest and highest rates

occurred (in order of magnitude of difference) in diabetes, injuries, mental disorders and

chronic respiratory diseases. The causes that contributed most in terms of the absolute

difference observed between socioeconomic quintiles were mental disorders (20.9%),

cardiovascular disease (17.6%) and diabetes (12.2%). Lifestyle-related (that is behavioural)

risk factors are important underlying risks for these conditions; the much greater burden

from these causes in lower socioeconomic areas is likely to be due to the greater prevalence

of lifestyle risk factors in these areas compared with higher socioeconomic areas. Limited

data availability on exposures by socioeconomic status, however, prevented further

exploration of this association.

110

Table 5.8: Differentials in burden (DALY rates) by socioeconomic quintile for the 10 leading broad

cause groups, Australia, 2003

Rate Standardised rate ratio(b) % diff. % of

Broad cause group Aust.(a) Low Mod. low Average Mod. high High high/low(c) total diff.(d)

Cancer 25.1 1.05 1.05 1.05 0.97 0.88 19.3 12.0

Cardiovascular 23.8 1.10 1.08 1.05 0.95 0.84 31.8 17.6

Mental 17.6 1.22 1.05 1.02 0.92 0.80 53.5 20.9

Neurological 15.7 1.02 1.02 1.03 1.00 0.93 10.2 4.2

Chronic respiratory 9.4 1.15 1.07 1.01 0.95 0.83 38.8 8.4

Diabetes 7.2 1.30 1.05 1.09 0.91 0.70 87.2 12.2

Unintentional injuries 6.3 1.14 1.12 1.12 0.93 0.72 57.8 7.3

Musculoskeletal 5.3 1.08 1.02 1.05 0.97 0.89 20.5 2.7

Genitourinary 3.3 1.07 1.02 1.04 0.97 0.92 16.0 1.4

Intentional injuries 3.0 1.28 1.11 1.00 0.91 0.73 75.1 4.6

All causes 132.4 1.12 1.05 1.04 0.96 0.85 31.7 100.0

(a) DALY rate for Australia per 1,000.

(b) Ratio of age-standardised DALYs per 1,000 population for area to DALYs per 1,000 population for Australia.

(c) Calculated for each cause as the greatest difference in DALY rates between areas as a proportion of lowest rate for that cause.

(d) Calculated for each cause as the greatest difference in DALY rates between areas as a proportion of greatest difference for all causes.

Table 5.9 lists the 10 leading specific causes of burden for Australia and summarises for each

socioeconomic quintile these causes in terms of rank order and percentage of total burden.

Ischaemic heart disease and anxiety & depression were the leading causes of burden across

all socioeconomic quintiles.

Table 5.9: Differentials in burden (DALYs) by socioeconomic quintile for the 10 leading specific

causes, Australia, 2003

Rank Per cent of total

Specific cause(a) Low

Mod.

low

Average

Mod.

high High Low

Mod.

low

Average

Mod.

high High

Ischaemic heart disease 1 1 1 1 1 9.8 10.5 10.2 9.6 9.8

Anxiety & depression 2 2 2 2 2 8.1 7.3 6.8 7.5 6.6

Type 2 diabetes 3 3 3 3 5 5.9 5.0 5.3 4.8 4.2

Stroke 4 4 4 4 3 4.0 4.6 4.6 4.5 4.9

Dementia 7 6 5 5 4 2.9 3.5 3.7 3.7 4.2

Lung cancer 6 5 6 6 6 3.5 3.6 3.5 3.2 3.0

COPD 5 7 7 7 7 3.7 3.5 3.3 3.1 2.8

Adult-onset hearing loss 9 8 9 8 11 2.4 2.5 2.5 2.6 2.4

Colorectal cancer 10 9 8 9 9 2.1 2.4 2.5 2.5 2.6

Asthma 8 10 11 11 10 2.5 2.4 2.2 2.5 2.5

(a) Sorted according to the leading specific causes for Australia.

111

5.5 Differentials by remoteness

The majority (64.5%) of the burden was experienced by people in the major cities as they

account for 67% of the population. Regional areas accounted for 33.1% of the burden and

remote areas 2.5% (Table 5.10). Males experienced more of this burden than females in all

areas, but particularly in remote areas. Remote areas experienced proportionately slightly

less fatal burden than other areas.

Table 5.10: Burden (DALYs) for remoteness categories by proportions of total, proportions by sex,

and proportions due to mortality, Australia, 2003

Area DALYs (’000) Per cent of total Per cent male Per cent fatal burden

Major cities 1,698.0 64.5 51.0 48.2

Regional 870.1 33.1 53.1 49.6

Remote 64.6 2.5 57.5 46.2

Australia 2,632.8 100.0 51.8 48.6

Total burden per head of population increased with remoteness, with remote populations

having 26.5% greater burden than populations in major cities. Again, this is due to higher

rates of burden for most causes, but particularly for injuries (Figure 5.5).

0

50

100

150

200

Remote Regional Major cities Remote Regional Major cities

Males Females

Cancer Cardiovascular Chronic respiratory Diabetes

Injuries Mental Neurological Other

Rate per 1,000

Figure 5.5: Age-standardised DALY rates per 1,000 by remoteness category, broad cause group

and sex, Australia, 2003

112

Table 5.11: Differentials in burden (DALY rates) by remoteness category for the 10 leading broad

cause groups, Australia, 2003

Rate Standardised rate ratio(b) % diff. % of

Broad cause group Aust.(a) Major cities Regional Remote high/low(c) total diff.(d)

Cancer 25.1 0.98 1.04 0.98 7.0 4.6

Cardiovascular 23.8 0.96 1.07 1.10 14.6 9.1

Mental 17.6 0.98 1.05 1.06 8.5 4.0

Neurological 15.7 0.99 1.03 1.03 4.2 1.8

Chronic respiratory 9.4 0.97 1.04 1.30 33.6 8.3

Diabetes 7.2 0.94 1.08 1.93 105.6 19.5

Unintentional

injuries 6.3 0.87 1.24 1.92 121.3 18.1

Musculoskeletal 5.3 0.95 1.10 0.99 16.0 2.2

Genitourinary 3.3 1.00 0.99 1.11 12.3 1.1

Intentional injuries 3.0 0.90 1.13 2.26 151.5 11.0

All causes 132.4 0.97 1.06 1.22 26.5 100.0

(a) DALY rate for Australia per 1,000.

(b) Ratio of age-standardised DALYs per 1,000 population for area to DALYs per 1,000 population for Australia.

(c) Calculated for each cause as the greatest difference in DALY rates between areas as a proportion of lowest rate for that cause.

(d) Calculated for each cause as the greatest difference in DALY rates between areas as a proportion of greatest difference for all causes.

Table 5.11 provides a comparison between burden rates for areas by remoteness category

and the national average for the 10 leading broad causes of burden in Australia for 2003. Of

these causes, the greatest difference between areas with the lowest and highest rates

occurred (in order of magnitude of difference) in injuries, diabetes, chronic respiratory

diseases, musculoskeletal disorders and cardiovascular disease. The cause that contributed

by far the greatest proportion in terms of the absolute difference observed between

remoteness categories was injuries (29.1% for intentional and unintentional combined),

followed by diabetes (19.5%) and cardiovascular disease (9.1%).

Table 5.12 lists the 10 leading specific causes of burden for Australia and summarises for

each remoteness category these causes in terms of rank order and percentage of total burden.

Type 2 diabetes was the leading cause of burden in remote areas whereas dementia was

ranked twelfth, reflecting the younger age structure and higher proportion of Indigenous

people in these areas compared with the rest of Australia.

113

Table 5.12: Differentials in burden (DALYs) by remoteness category for the 10 leading specific

causes, Australia, 2003

Rank Per cent of total

Specific cause(a) Major cities Regional Remote Major cities Regional Remote

Ischaemic heart disease 1 1 2 9.8 10.6 7.3

Anxiety & depression 2 2 3 7.4 7.1 6.4

Type 2 diabetes 3 3 1 4.9 5.1 7.7

Stroke 4 4 8 4.6 4.4 2.8

Dementia 5 7 12 3.8 3.3 2.0

Lung cancer 6 6 10 3.4 3.5 2.6

COPD 7 5 4 3.1 3.6 3.8

Adult-onset hearing loss 11 8 11 2.3 2.7 2.1

Colorectal cancer 9 9 15 2.4 2.5 1.4

Asthma 8 10 9 2.5 2.3 2.7

(a) Sorted according to the leading specific causes for Australia.

114

6 Past, present and future burden of

disease and injury in Australia

6.1 Overview

This chapter presents trends in population health dynamics over a thirty-year period. The

analyses involved consideration of health statistics over the last 25 years or more, although

the discussion about the past is linked to health trends over the last decade. Also presented

are the projected levels of the burden of disease and injury if these trends were to continue

20 years into the future. Since mortality is the starting point for many of these analyses,

observed and projected trends in mortality by broad cause group are summarised in Table

6.1. The methods underlying all analyses presented in this chapter are described in detail in

Chapter 2.

Table 6.1: Changes in mortality by broad cause group and sex, Australia, 1993 to 2023

Standardised rate ratio(a)

Rate per 100,000

for 2003 Males Females

Broad cause group Males Females 1993 2003 2013 2023 1993 2003 2013 2023

Infectious 14.8 9.5 0.93 1.00 0.97 0.92 0.95 1.00 0.92 0.83

Acute respiratory(b) 16.5 20.9 0.43 1.00 1.00 1.00 0.40 1.00 1.00 1.00

Maternal — 0.1 — — — — 1.87 1.00 1.26 1.19

Neonatal 3.6 2.7 1.74 1.00 0.63 0.41 1.01 1.00 0.66 0.46

Nutritional 0.2 0.6 2.83 1.00 1.24 1.09 1.72 1.00 0.74 0.65

Cancer 211.1 163.7 1.20 1.00 0.89 0.75 1.12 1.00 0.92 0.82

Other neoplasms 4.3 4.1 1.06 1.00 0.88 0.74 0.92 1.00 0.96 0.91

Diabetes 19.5 16.6 1.01 1.00 0.96 0.90 1.13 1.00 0.88 0.76

Endocrine 5.6 7.0 1.73 1.00 1.00 0.89 0.95 1.00 1.07 1.06

Mental 10.4 3.4 1.18 1.00 0.90 0.75 1.10 1.00 0.91 0.79

Neurological 27.8 41.7 1.10 1.00 0.99 0.91 0.93 1.00 1.04 1.05

Cardiovascular 237.9 252.6 1.61 1.00 0.71 0.47 1.52 1.00 0.76 0.52

Chronic respiratory 48.1 37.7 1.38 1.00 0.82 0.69 1.00 1.00 1.04 1.07

Digestive 14.7 19.4 1.18 1.00 0.74 0.55 1.13 1.00 0.80 0.63

Genitourinary 16.7 20.1 1.01 1.00 0.95 0.87 0.86 1.00 0.98 0.93

Skin 1.2 2.0 1.06 1.00 0.96 0.83 0.88 1.00 1.03 1.04

Musculoskeletal 2.6 5.1 1.29 1.00 0.94 0.79 1.10 1.00 0.95 0.90

Congenital 4.2 3.4 1.17 1.00 0.75 0.60 1.30 1.00 0.75 0.58

Oral 0.0 0.1 1.61 1.00 1.29 1.11 0.39 1.00 0.73 0.74

Ill defined 0.5 0.6 3.13 1.00 0.54 0.25 2.01 1.00 0.69 0.52

Injuries 52.4 27.7 1.13 1.00 0.87 0.73 1.00 1.00 0.87 0.74

All causes 692.1 639.0 1.32 1.00 0.83 0.67 1.22 1.00 0.87 0.73

(a) Ratio of age-standardised mortality rates for year to mortality rates for 2003.

(b) Age-specific rates for pneumonia post-2003 held at 2003 rates due to coding discontinuities between ICD-9 and ICD-10 for this cause.

115

6.2 Health-adjusted life expectancy

This section begins, as did Chapter 5, by presenting life expectancy and health-adjusted life

expectancy, but this time with a temporal dimension rather than with a focus on differentials

between subpopulations. Over the last decade, total life expectancy in Australia improved

from 78.0 years in 1993 to 80.7 years in 2003. This was an annual growth of 0.35% (or 0.28 of a

year per year). If past mortality trends continue into the future as projected (that is, at an

exponentially declining rate), life expectancy will increase to 82.6 years in 2013 and 84.6 years

in 2023, an increase of 3.9 years from 2003. This represents an annual growth of 0.24% (or

0.20 of a year per year) over the 20-year period (Table 6.2).

Table 6.2: Life expectancy and health-adjusted life expectancy by sex, Australia, 1993 to 2023

1993 2003 2013 2023

Males Females Both Males Females Both Males Females Both Males Females Both

Population(a)

(millions) 8.8 8.9 17.7 9.9 10.0 19.9 11.0 11.2 22.2 12.1 12.3 24.5

Proportion of population at selected ages (%)

0–59 years 85.8 82.8 84.3 84.1 81.6 82.8 79.8 77.6 78.7 75.1 72.7 73.9

60–79 years 12.5 14.1 13.3 13.5 14.2 13.9 16.9 17.3 17.1 20.3 21.1 20.7

80+ years 1.6 3.2 2.4 2.4 4.2 3.3 3.4 5.1 4.2 4.6 6.1 5.4

Life expectancy (years)

At birth 75.0 81.0 78.0 78.3 83.2 80.7 80.6 84.8 82.6 83.3 86.5 84.6

At age 60 19.5 23.8 21.7 22.1 25.6 23.9 23.7 26.8 25.2 25.9 28.1 26.8

At age 80 7.2 9.1 8.4 8.4 9.9 9.3 9.1 10.5 9.8 10.6 11.3 10.7

Health-adjusted life expectancy (years)

At birth 68.0 73.5 70.7 70.6 75.2 72.9 72.5 76.6 74.5 74.7 78.0 76.2

At age 60 15.2 19.2 17.3 17.1 20.5 18.9 18.4 21.5 19.9 20.1 22.5 21.2

At age 80 4.7 6.3 5.6 5.4 6.8 6.2 5.9 7.2 6.6 6.8 7.7 7.1

Healthy life expectancy lost due to disability (years)

At birth 7.0 7.5 7.3 7.7 7.9 7.8 8.0 8.2 8.1 8.6 8.5 8.5

At age 60 4.4 4.6 4.5 5.0 5.1 5.0 5.3 5.3 5.2 5.8 5.6 5.6

At age 80 2.5 2.8 2.7 3.0 3.2 3.1 3.2 3.3 3.3 3.7 3.6 3.5

Healthy life expectancy lost due to disability as proportion of total life expectancy (%)

At birth 9.4 9.2 9.3 9.8 9.6 9.7 9.9 9.6 9.8 10.3 9.9 10.0

At age 60 22.3 19.3 20.6 22.6 19.8 21.1 22.2 19.7 20.8 22.6 19.9 21.0

At age 80 35.2 31.1 32.5 35.8 31.8 33.2 35.3 31.8 33.1 35.4 31.9 33.3

(a) Estimated resident population figures as at 30 June 1993 and 2003 (ABS 2006, Cat. no. 3201.0, Table 9) and ABS population projections

series 8 (ABS 2003a, Cat. no. 3222.0).

Health-adjusted life expectancy, on the other hand, increased from 70.7 years to 72.9 years in

the decade to 2003, an annual growth of 0.31% (or 0.22 of a year per year). If, in addition to

past mortality trends, trends in non-fatal health conditions that give rise to disability

continue into the future as projected, health-adjusted life expectancy will increase to 74.5

years in 2013 and 76.2 years in 2023. This represents an annual growth of 0.22% (or 0.16 of a

year per year) over the 20-year period.

116

Complex dynamics in population health will drive the slower gains in health-adjusted life

expectancy relative to total life expectancy. The most important of these is the decline in

mortality rates between 1993 and 2023 across the life span, but particularly in the elderly

(Figure 6.1a). One of the consequences of declining mortality is that, in combination with

ongoing declines in fertility, Australia’s population will continue to age. Of particular

relevance is the number of people aged 80 years and older. Over the last decade, the

proportion of the total population in this age group increased from 2.4% in 1993 to 3.3% in

2003. Based on recent Australian Bureau of Statistics (ABS) projections (ABS 2003a), this is

expected to increase to 4.2% in 2013 and 5.4% in 2023 (Table 6.2).

0

100

200

300

100

200

300

400

60 70 80 90 100 60 70 80 90 100

Mortality Disability

1993 2023

Rate per 1,000

Age

Figure 6.1: Age-specific (a) mortality, and (b) total prevalence-based years lived with

disability (PYLD) expressed as rates per 1,000 in the elderly for both sexes combined,

Australia, 1993 and 2023

The impact on life expectancy of declining mortality rates is straightforward—it will

increase. The impact on health-adjusted life expectancy and its corollary, life expectancy lost

due to disability, however, is perhaps less intuitive at first. The key point is that, in most

populations, even if the prevalence of disability at each age were to remain at constant levels,

a decline in mortality would mean an increase in life expectancy lost due to disability in the

future (Figure 6.2). This is because reductions in mortality result in more people surviving

through to ages when the probability of being disabled is highest. Ultimately, though, this

relationship depends on changes in the rate at which mortality increases with age relative to

changes in the rate at which disability increases with age.

117

0

5

10

0 50 100 0 50 100

Males Females

1993 2023

LE lost due to (years)

Age

Figure 6.2: Impact on life expectancy lost due to disability (years) of declining mortality

and constant (1993) levels of disability, Australia, 1993 to 2023

In addition to the increase in the proportion of total life expectancy lost due to disability

through reductions in mortality, is the impact of temporal trends in diseases and injuries that

give rise to the prevalence of disability. By estimating separately the epidemiology of these

causes in a fully temporal model, changes in total prevalence of disability by age, sex and

cause can be quantified for the first time over the past as well as into the future.

While the prevalence of overall disability appears to decrease when the effect of population

ageing is removed (by standardising for age), it will consistently increase over the next two

decades in crude terms (Figure 6.3). In other words, the proportion of overall time lived with

disability will increase from 7.8% in 2003 to 8.9% in 2023, an increase of 14.1%.

8.0

7.8

7.6

7.5

7.4

7.8

8.3

8.9

7

8

9

1993 2003 2013 2023 1993 2003 2013 2023

Standardised Crude

Prevalence Year

Figure 6.3: Age-standardised and crude total prevalence-based years lived with disability

(PYLD) for both sexes combined, Australia, 1993 to 2023

This is for two reasons. First, the number of people aged 80 years and over is set to expand

rapidly due to declining mortality (Figure 6.1a). Second, while the prevalence of disability

will drop at most ages, it will actually increase in this age group (Figure 6.1b). In the decade

disability (%)

118

to 2003, disability in people aged 80 years and over increased by 2.0%; if past trends

continue, by 2023 disability will have increased a further 1.7% (Figure 6.4). This lends

support to the hypothesis which predicts that as population health improves, disability is

increasingly concentrated towards the end of the life span.

0.0

-6.2

-11.0

-13.8

0.0

-0.5

-6.3

-9.4

2.0

3.3 3.7

-15

0

15

1993 2003 2013 2023 1993 2003 2013 2023 1993 2003 2013 2023

60-69 years 70-79 years 80+ years

Change from 1993 (%)

Year

Figure 6.4: Per cent change in the rates of total prevalence-based years lived with disability

(PYLD) since 1993 at selected age groups for both sexes combined, Australia, 2003 to 2023

The effect on health-adjusted life expectancy of the increasing concentration of disability

towards the end of life, which until now has been largely unexplored using empirical data,

can be illustrated by gains in expectation of life in a model in which disability is included as

a dynamic force over time, compared with a counterfactual scenario in which the probability

of disability is held constant (Figure 6.5 and Figure 6.6). Such a comparison provides insights

into the question ‘What impact will concentration of disability towards the end of the

lifespan have on health-adjusted life expectancy?’

Health-adjusted life expectancy at birth is the most commonly cited measure, and

summarises mortality and disability risks across the life span. In males, this will increase at a

rate faster than would have been observed through reductions in mortality alone, with the

net effect of morbidity being increasingly concentrated towards the end of life. From 1993 to

2003 the gain was about 0.2 years. Over the longer term, however, the gain will be larger, at

around 0.8 years of healthy life for males born in 2023. At adult ages, the gains are less and,

in the elderly, where gains in health expectancy due to declines in mortality are more easily

offset by increases in disability, there were losses in healthy life due to this dynamic in the

decade to 2003, but these disappear in the subsequent decade (Figure 6.5).

––11.0

––0.5

–6.3

–0.0

2.0

60–69 years 70–79 years 80+ years

–0

119

-.8

-.6

-.4

-.2

0

.2

.4

.6

.8

0 50 100 0 50 100 0 50 100

2003 2013 2023

Net gain (years)

Age

Figure 6.5: Net years gained in health-adjusted life expectancy (years) from changes in

prevalence of disability compared with baseline (1993) levels of disability for males,

Australia, 2003 to 2023

In females, the impact of morbidity being increasingly concentrated towards the end of life is

not readily apparent in the decade to 2003. Over the next two decades this dynamic will start

to have an impact, although the gains in health expectancy at birth will be smaller than for

males (around 0.3 years in 2023) and the losses in the elderly will be greater and will be

experienced earlier in life.

-.8

-.6

-.4

-.2

0

.2

.4

.6

.8

0 50 100 0 50 100 0 50 100

2003 2013 2023

Net gain (years)

Age

Figure 6.6: Net years gained in health-adjusted life expectancy (years) from changes in

prevalence of disability compared with baseline (1993) levels of disability for females,

Australia, 2003 to 2023

The correct answer to the question ‘What impact will the concentration of disability in the

latter part of the lifespan have on health-adjusted life expectancy?’, therefore, is: ‘It depends’.

This is because health expectancy at any particular age is a summary measure based on the

–0.8

–0.6

–0.4

–0.2

0

0.2

0.4

0.6

0.8

–0.8

–0.6

–0.4

–0.2

0

0.2

0.4

0.6

0.8

Age

Age

120

combination of mortality and disability risks at that age and all subsequent ages. While a

detailed decomposition of the drivers of this complex dynamic is beyond the scope of this

report, growth in prevalent disability in the elderly is likely to come from increases in

diabetes and neurological conditions. Disability from diabetes, in particular, grew 10.4% in

the decade to 2003, and will grow a further 29.3% over the next two decades if current trends

in obesity continue (Figure 6.7). Neurological conditions grew 2.5% in the decade to 2003,

and are likely to grow a further 6.6% in the 20 years to 2023. Most other causes of prevalent

disability are likely to decline.

-3.3

-13.0

-23.1

10.4

24.7

2.5

9.1

-9.4

-18.8

-27.7

-3.5 -9.2

-16.1

6.8

8.6 10.6

-40

0

40

-40

0

40

-40

0

40

-40

0

40

-40

0

40

-40

0

40

1993 2003 2013 2023 1993 2003 2013 2023 1993 2003 2013 2023

1993 2003 2013 2023 1993 2003 2013 2023 1993 2003 2013 2023

Cancer Diabetes Neurological

Cardiovascular Injuries Other

Change from 1993 (%)

Year

Figure 6.7: Percentage change in disability (PYLD) prevalence rates since 1993 for selected

causes in people aged 80 years and over, Australia, 2003 to 2023

Figure 6.8 shows the number of healthy years lost due to prevalent disability (PYLD) by

cause and age for 1993 and 2023. This figure demonstrates the absolute growth in PYLD that

is expected to occur over this period due to increases in population size. It also shows the

shift in the distribution of PYLD towards older ages that will occur as a result of population

ageing. Trends in epidemiology will interact with these demographic factors to influence the

composition of causes of prevalent disability at each age. Neurological conditions will grow

substantially over the period 1993 to 2023 and will remain the largest contributor to

disability prevalence at older ages. Mental disorders, on the other hand, will grow only

slightly from 1993 levels but will remain the largest contributor to disability prevalence until

age 60. Disability from cardiovascular disease is expected to decline from middle age

onwards over this period but this decline will be more than offset by increases from diabetes.

–40

0

40

–40

0

40

–0

40

–40

0

40

–40

0

40

––3.3

0.0

–13.0

–23.1

–9.4

0.0

–18.8

–27.7

–3.5

0.0

–9.2

–16.1

0.0

39.7

0.0 6.7 0.0

Year

121

0

100

200

Number (thousands)

0 20 40 60 80 100

Age

Other

Injuries

Cancer

Musculoskeletal

Cardiovascular

Diabetes

Chronic respiratory

Neurological

Mental

1993

0

100

200

Number (thousands)

0 20 40 60 80 100

Age

2023

Figure 6.8: Prevalence of disability (PYLD) due to selected broad cause groups for both

sexes combined by age, Australia, 1993 and 2023

Changes in the age-specific trends described above reflect changes in the prevalence of

disability experienced at all ages (Figure 6.9). Mental disorders decreased from 26% to 25% of

total prevalence of disability in the decade to 2003. The effects of population ageing will

mean that mental disorders, which are largely experienced in early to middle adulthood, will

further decline to 22% of total prevalent disability in 2023, although they will remain the

leading cause of overall prevalent disability. Neurological & sense disorders, on the other

hand, will increase as a consequence of population ageing because they are experienced later

in life. In the decade to 2003 this group increased from 15% to 17% of total prevalent

disability in 2003, and over the next two decades, through population ageing alone, will

increase to 21% in 2023.

122

Figure 6.9: Proportion of total prevalence of disability (PYLD) due to selected

broad cause groups, Australia, 1993 to 2023

Diabetes was the other strong growth area at all ages, increasing from 5% of total prevalent

disability in 1993 to 6% in 2003. If current trends in obesity continue, this figure is set to

increase by a further 50% to 9% of total prevalent disability in 2023.

6.3 Burden

The remainder of this chapter presents past, present and future burden using the standard

burden measure—DALYs. It is worth reiterating at this point that, unlike prevalent years

lived with disability (PYLD), DALYs are incidence-based and include, in addition to nonfatal

health outcomes, time lost due to premature mortality. Observed and projected trends

in burden (DALYs) by broad cause group are summarised in Table 6.3. The methods

underlying these figures are described in detail in Chapter 2. More detailed data on past,

Mental

Neurological

Chronic

respiratory

Cardiovascular

Diabetes

Musculoskeletal

Cancer

Injuries

Other

26%

15%

8% 10%

5%

6%

6%

6%

18%

Mental

Neurological

Chronic

respiratory

Cardiovascular

Diabetes

Musculoskeletal

Cancer

Injuries

Other

25%

17%

8% 10%

6%

6%

6%

5%

17%

Mental

Neurological

Chronic

respiratory

Cardiovascular

Diabetes

Musculoskeletal

Cancer

Injuries

Other

24%

19%

7% 9%

8%

6%

5%

5%

17%

Mental

Neurological

Chronic

respiratory

Cardiovascular

Diabetes

Musculoskeletal

Cancer

Injuries

Other

22%

21%

7% 9%

9%

7%

5%

4%

16%

1993 2003

2013 2023

123

present and future burden by age, sex and cause is available on the web at

<www.aihw.gov.au/bod>.

Table 6.3: Changes in burden rates (DALYs) by broad cause group and sex, Australia, 1993 to 2023

Standardised rate ratio(a)

Rate per 1,000

for 2003 Males Females

Broad cause group Males Females 1993 2003 2013 2023 1993 2003 2013 2023

Infectious 2.8 1.7 0.93 1.00 1.02 0.99 0.99 1.00 0.93 0.85

Acute respiratory(b) 1.7 1.8 0.67 1.00 1.00 1.00 0.61 1.00 1.00 1.00

Maternal — 0.2 — — — — 1.09 1.00 1.03 1.02

Neonatal 1.9 1.6 1.32 1.00 0.80 0.68 1.00 1.00 0.82 0.71

Nutritional 0.1 0.5 1.12 1.00 1.03 1.02 1.03 1.00 0.99 0.98

Cancer 26.8 23.5 1.20 1.00 0.85 0.70 1.16 1.00 0.88 0.74

Other neoplasms 0.5 0.6 1.03 1.00 0.83 0.68 0.94 1.00 0.89 0.81

Diabetes 7.8 6.6 0.87 1.00 1.15 1.32 0.89 1.00 1.18 1.40

Endocrine 1.5 1.4 1.88 1.00 1.08 1.03 0.89 1.00 1.16 1.31

Mental 16.8 18.5 1.03 1.00 1.01 0.99 0.99 1.00 1.01 1.01

Neurological 14.9 16.6 0.96 1.00 1.02 1.03 0.96 1.00 1.03 1.05

Cardiovascular 25.6 22.1 1.56 1.00 0.69 0.48 1.51 1.00 0.74 0.53

Chronic respiratory 10.0 8.8 1.22 1.00 0.83 0.73 1.04 1.00 0.96 0.93

Digestive 2.9 2.9 1.01 1.00 0.81 0.71 1.03 1.00 0.85 0.75

Genitourinary 2.9 3.7 0.97 1.00 0.97 0.96 0.97 1.00 0.98 0.95

Skin 1.0 1.0 1.00 1.00 1.00 0.99 1.00 1.00 1.00 0.99

Musculoskeletal 4.5 6.1 0.98 1.00 1.03 1.05 0.97 1.00 1.02 1.02

Congenital 1.9 1.4 1.11 1.00 0.84 0.74 1.19 1.00 0.84 0.72

Oral 1.2 1.3 0.99 1.00 1.02 1.03 0.98 1.00 1.01 1.02

Ill defined 0.5 0.7 1.70 1.00 0.83 0.73 1.31 1.00 0.93 0.89

Injuries 13.1 5.5 1.16 1.00 0.91 0.79 1.08 1.00 0.89 0.76

All causes 138.2 126.7 1.18 1.00 0.90 0.81 1.11 1.00 0.93 0.87

(a) Ratio of age-standardised DALY rates for year to DALY rates for 2003.

(b) Age-specific rates for pneumonia post-2003 held at 2003 rates due to coding discontinuities between ICD-9 and ICD-10 for this cause.

As observed with PYLD, total burden will most likely decrease after the effect of population

ageing is removed (that is, age-standardisation) over the next two decades, yet in crude

terms it will most likely increase (Figure 6.10). Again, this is due to a larger proportion of the

population alive at older ages.

124

151.0

132.4

121.1

111.4

139.8

132.4 132.4

135.1

100

125

150

175

1993 2003 2013 2023 1993 2003 2013 2023

Standardised Crude

Rate per 1,000

Year

Figure 6.10: Age-standardised and crude burden (DALY) rates for both sexes combined,

Australia, 1993 to 2023

Chapter 3 described the decline of cardiovascular disease relative to cancer as a proportion of

overall burden, and stated that for the first time, cancer accounted for the largest share of

overall burden experienced by the Australian population in 2003. This is primarily because

Australia has been relatively successful at curbing the impact of the cardiovascular disease

epidemic, but not nearly as successful to date with cancer. If these trends continue, the

burden of cardiovascular disease will further decline to about 13% of the total burden in

2023. The age-standardised rates of cancer mortality and disability are expected to fall

somewhat in the future but cancer as a whole will retain its share of around 19% of total

burden two decades from now and will remain the largest contributor to total burden in 2023

(Figure 6.11).

Despite the steady decline in cardiovascular disease burden over the next two decades, there

is likely to be a strong increase in burden due to diabetes, primarily as a consequence of the

obesity epidemic. If current trends in obesity continue unabated, diabetes will account for

around 9% of total burden in 2023, up from around 5% in 2003 (Figure 6.11).

A major consequence of population ageing will be the steady growth in burden from

neurological & sense disorders, up from 12% in 2003 to around 16% in 2023. The main

contributors here will be dementia and adult-onset hearing loss, both causes for which

current treatments are largely ineffectual. The economic consequences of the former in terms

of the provision of appropriate care services are likely to be significant and will be evident in

the home and community sectors before they are felt in the residential aged care sector.

125

Cancer

Cardiovascular

Neurological

Mental

Chronic

respiratory

Injuries

Diabetes

Musculoskeletal

Other

19%

22%

13% 10%

7%

8%

4%3%

14%

Cancer

Cardiovascular

NeuroMental

logical

Chronic

respiratory

Injuries

Diabetes

Musculoskeletal

Other

19%

18%

13% 12%

7%

7%

5%

4%

14%

Cancer

Cardiovascular

NeuroMental

logical

Chronic

respiratory

Injuries

Diabetes

Musculoskeletal

Other

19%

15%

13% 14%

7%

6%

7%

4%

14%

Cancer

Cardiovascular

Neurological

Mental

Chronic

respiratory

Injuries

Diabetes

Musculoskeletal

Other

18%

13%

16%

12%

7%

5%

9%

5%

14%

1993 2003

2013 2023

Figure 6.11: Proportion of total burden (DALYs) due to selected broad cause

groups, Australia, 1993 to 2023

The proportion of burden due to major causes experienced at different ages throughout the

life span is unlikely to change dramatically over the next two decades (Figure 6.12). The

decline of cardiovascular disease as a proportion of total burden will be experienced at all

ages, although, in absolute terms, most notably in the elderly. This will be partially offset by

the increase in the proportion due to diabetes at all ages. The proportion of total burden due

to cancer at different ages is unlikely to change.

126

0

200

400

Number (thousands)

0 20 40 60 80 100

Age

Other

Musculoskeletal

Injuries

Diabetes

Chronic respiratory

Mental

Neurological

Cardiovascular

Cancer

1993

0

200

400

Number (thousands)

0 20 40 60 80 100

Age

2023

Figure 6.12: Burden (DALYs) due to selected broad cause groups for both sexes combined

by age, Australia, 1993 and 2023

In terms of specific causes of disease burden, ischaemic heart disease is the leading cause in

males across three of the four time periods. Its share of burden declined from 14.7% in 1993

to 11.1% in 2003 (Table 6.4). If this trend continues, ischaemic heart disease will decline a

further 36% to 7.1% of the total burden in 2023. Type 2 diabetes, on the other hand, rose from

sixth place to second in the decade to 2003, and is likely to increase a further 65% to first

place or 8.6% of the total burden in 2023. Anxiety & depression will retain its third place, at

around 4.5% of the total burden in 2023, but lung cancer will drop to sixth place, largely

because of the dramatic decline in smoking prevalence in males over the last two decades. In

its place, dementia will occupy fourth position in 2023, up from 11th place in 2003.

127

Table 6.4 Leading causes of burden (DALYs) in males, Australia, 1993 to 2023

Rank(a) Per cent of total

Specific cause 1993 2003 2013 2023 1993 2003 2013 2023

Ischaemic heart disease 1 1 1 2 14.7 11.1 8.9 7.1

Type 2 diabetes 6 2 2 1 3.6 5.2 6.8 8.6

Anxiety & depression 2 3 3 3 4.5 4.8 4.7 4.5

Lung cancer 3 4 4 6 4.4 4.0 3.8 3.4

Stroke 5 5 6 7 4.2 3.9 3.5 3.2

COPD 4 6 9 11 4.4 3.6 2.9 2.2

Adult-onset hearing loss 11 7 5 5 2.5 3.1 3.7 4.2

Suicide & self-inflicted injuries 8 8 10 10 2.9 2.8 2.8 2.4

Prostate cancer 10 9 8 8 2.5 2.7 3.0 3.1

Colorectal cancer 9 10 11 9 2.6 2.5 2.6 2.4

Dementia 14 11 7 4 1.8 2.5 3.3 4.4

Road traffic accidents 7 12 14 18 3.0 2.3 1.8 1.3

Asthma 12 13 12 12 2.2 2.1 2.0 1.9

Alcohol dependence & harmful use 13 14 13 14 2.0 2.0 1.9 1.6

Personality disorders 16 15 17 19 1.1 1.2 1.2 1.2

Schizophrenia 15 16 20 23 1.1 1.1 1.1 1.0

Osteoarthritis 24 17 15 15 0.8 1.1 1.3 1.6

Back pain 23 18 18 17 0.9 1.1 1.2 1.3

Melanoma 20 19 21 20 0.9 1.0 1.1 1.1

Parkinson’s disease 25 20 16 13 0.8 1.0 1.3 1.6

(a) Sorted according to the leading specific causes for Australia in the year 2003.

Anxiety & depression is ranked first in females across three of the four time periods,

although in percentage terms its share of the total burden will decrease from 10.0% in 2003 to

8.7% in 2023 (Table 6.5). Ischaemic heart disease will remain in second place over the next

decade, but fall to fourth place by 2023. In its place will be dementia, which increased by 1.1

percentage points to 4.8% of the total burden in the decade to 2003, and, if current projections

of population ageing eventuate, will be ranked third at 7.4% of the total burden in 2023. As

with males, Type 2 diabetes is set to increase steadily and is likely to occupy second position

in 2023, at around 8% of the total burden.

128

Table 6.5 Leading causes of burden (DALYs) in females, Australia, 1993 to 2023

Rank(a) Per cent of total

Specific cause 1993 2003 2013 2023 1993 2003 2013 2023

Anxiety & depression 2 1 1 1 9.8 10.0 9.6 8.7

Ischaemic heart disease 1 2 2 4 12.4 8.9 7.5 6.1

Stroke 3 3 5 5 5.9 5.1 4.4 3.8

Type 2 diabetes 6 4 3 2 3.7 4.9 6.4 8.0

Dementia 5 5 4 3 3.7 4.8 5.9 7.4

Breast cancer 4 6 6 6 5.1 4.8 4.3 3.5

COPD 7 7 8 8 3.1 3.0 2.9 2.8

Lung cancer 10 8 7 7 2.3 2.7 3.1 3.5

Asthma 8 9 9 9 2.9 2.7 2.5 2.4

Colorectal cancer 9 10 10 12 2.6 2.3 2.2 1.9

Adult-onset hearing loss 11 11 11 11 1.5 1.8 2.0 2.2

Osteoarthritis 12 12 12 10 1.4 1.6 1.9 2.2

Personality disorders 15 13 14 16 1.2 1.3 1.3 1.3

Migraine 14 14 17 18 1.3 1.3 1.2 1.1

Back pain 16 15 15 15 1.1 1.2 1.3 1.3

Lower respiratory tract infections 38 16 13 13 0.5 1.1 1.3 1.6

Falls 20 17 18 19 0.9 1.0 1.1 1.1

Parkinson’s disease 19 18 16 14 0.9 1.0 1.2 1.5

Schizophrenia 17 19 20 25 1.0 1.0 1.0 0.9

Rheumatoid arthritis 21 20 19 20 0.9 1.0 1.0 1.0

(a) Sorted according to the leading specific causes for Australia in the year 2003.

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7 Discussion and conclusions

7.1 Potential applications

A detailed description of the burden of disease and injury in a population is not sufficient for

setting priorities in public health. It is, however, an important foundation on which to build

assessments and evaluations that underpin health policies. This report contributes most

obviously by identifying the magnitude of health problems in a population and by

quantifying the contribution to these problems of major modifiable risks to health. The

present study greatly extends the scope of the previous study in this respect by presenting

burden estimates for a greater range of population subgroups in Australia. It also provides a

cogent analysis of past trends in burden in this country, and suggests the likely state of the

population’s health in 20 years from now if these trends were to continue. Furthermore, it

quantifies the contribution to overall burden of an expanded set of risks to health.

Equally important, however, is the contribution of burden estimation to down-stream

analyses by the creation of a consistent set of epidemiological parameters for a full range of

health conditions, and a detailed description of the relationship between these parameters

and risks to health. Again, the study upon which this report is based expands the scope of

such analyses through the creation of a comprehensive database of all relevant

epidemiological and burden parameters both for a number of different subpopulations and

through time. The most obvious synergy here is with cost-effectiveness analyses of the

potential outcomes of health interventions. Estimates from the previous study have been

used extensively in a number of economic evaluation studies to date (for example, Nelson et

al. 2005; Stone et al. 2004; Vos et al. 2005). This new set of results has been incorporated into

models under development for the project funded by the National Health and Medical

Research Council ‘Assessing Cost-Effectiveness (ACE)—Prevention’, at the University of

Queensland and University of Melbourne, the aim of which is to comprehensively model the

cost-effectiveness of preventive intervention options for non-communicable disease in

Australia.

The essential link between burden of disease and injury data and cost-effectiveness results is

acknowledged by the Pharmaceutical Benefits Advisory Committee, which now requires

companies to present evidence on the likely uptake of a new drug in the population. This

requires knowledge about the number of people with a particular condition or risk profile

for whom the drug is intended. This report will be invaluable as a common reference point.

An important new application of the results of this study will be to further improve

estimates of future health expenditure in this country. As life expectancy continues to

increase and populations continue to age, this is an area of concern to governments, not only

in Australia but around the world. Projections for the 2002 Intergenerational Report relied on

models that do not take into account major shifts in epidemiology and expenditure for some

diseases. The projections in this report have already been linked to health expenditure data

(AIHW 2005c), thus enabling more detailed health expenditure projections for these causes

(for example, Vos et al. 2007).

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7.2 Policy implications

The preceding section illustrated that the analyses underpinning this report are not sufficient

on their own as a basis for setting future directions in health policy. A number of other

inputs are also necessary, not the least of which is evidence on the costs and effectiveness of

available interventions. Nevertheless a number of important implications for policy arise

from the findings presented in the preceding chapters.

This report has presented for the first time a comprehensive overview of the likely effects of

population ageing on patterns of disease and injury in Australia over the next 20 years.

These projections are based on analyses of past trends in health and are presented as a

‘business as usual’ scenario (that is, the rate of change in policy responses to emerging

problems in the future is consistent with the rate observed in the historical period upon

which the projections are based). While all projections regarding the future are uncertain,

including those presented in this report, some are more uncertain than others. This is

particularly true for the projections for diabetes, where information on trends is limited to

one cross-sectional survey and some assumptions regarding changes in case-fatality relative

to those observed for ischaemic heart disease (assumptions which are corroborated by the

second round of the Australian Diabetes, Obesity and Lifestyle study). Notwithstanding

these caveats, the general tenor of these analyses is clear.

A key finding of this study is that while life expectancy is likely to continue increasing

steadily, growth in health-adjusted life expectancy will not be as rapid. This is because the

number of very old people is set to expand rapidly, mostly due to declining mortality. In

addition, while the prevalence of disability will drop at most ages, it is expected to increase

for people aged 80 years and over.

A major consequence of this population dynamic will be the steady growth in the burden

from diseases associated with old age such as dementia, Parkinson’s disease, hearing and

vision loss, and osteoarthritis, all causes for which current prevention and (with the

exception of osteoarthritis and cataract) treatment strategies are largely ineffectual. The

impact of increasing disability from these diseases is likely to be significant and will be felt in

the home and the community care sectors before it is felt in the residential aged care and

palliative care sectors. While future research into prevention and treatment may yield

unexpected results, relevant stakeholders should be planning for growth in the number of

elderly people requiring appropriate services in each of these care settings. The economic

consequences of these changes on future health care expenditure have been quantified in a

separate report (Vos et al. 2007), which it is hoped might assist the development of

appropriate policy responses in this area.

In addition, cardiovascular disease are likely to continue to decline relative to cancer as a

proportion of the overall burden, primarily because current health care has been relatively

successful at curbing the effects of the former, but not nearly as successful with the latter.

Successful reductions of cardiovascular disease should not obscure the fact that additional

gains could be made by further reductions in levels of cholesterol, blood pressure and

smoking, the primary risk factors for these diseases (Taylor et al. 2006). Increasing the

coverage and targeting of interventions known to be effective (for example dietary

modification, cholesterol and blood pressure lowering drugs, and smoking cessation) is one

way of achieving this. There is also likely to be scope for increased efficiency through the

adoption of a more cost-effective mix of interventions.

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Lastly, the projected strong growth in the burden from diabetes over the next 20 years is an

area of concern. This is mostly a consequence of increases in body weight. The consequences

of increasing obesity will be further magnified by reductions in case-fatality from

cardiovascular disease — the major cause of mortality in people with diabetes — through

successful tobacco control and cholesterol and blood pressure lowering strategies. This

increased survival will mean an increase in the risk of developing other largely non-fatal but

disabling consequences of diabetes such as renal failure, retinopathy, neuropathy and

peripheral vascular disease. Efforts to find new approaches to stem rising levels of obesity

need to continue.

7.3 Precision of estimates

Fatal burden

The calculation of fatal burden (YLL) is relatively straightforward and the precision of these

estimates is almost entirely dependent on the quality of information on underlying cause of

death in official mortality data. While every effort has been made to remedy likely

distortions to the overall reported cause of death structure by reallocating deaths with

certain codes known to be non-specific to valid and specific underlying causes of death, by

world standards the extent of these distortions is small (around 6% to 10%, depending on the

codes included in this definition). Of greater concern are the deaths coded to valid and

specific causes of death. With the exception of a few studies on sensitivity and specificity for

specific conditions, relatively little is known about the accuracy of causal attribution for the

majority of cases. It is likely that accuracy varies with the location of the death due to

differential access to diagnostic information (for example in an institutional setting versus at

home), but the assumption that these inaccuracies will cancel each other out at the

population level is largely speculative. Further research in this area would greatly enhance

the integrity of the vital registration system in this country.

Non-fatal burden

The accuracy of estimates of disability is not quantifiable using formal statistical techniques.

This is because, in the construction of these estimates, data of widely varying levels of

quality, ranging from population level disease registers and high quality research findings at

one end to ‘guesstimates’ and expert opinion at the other, was drawn upon. Precision is

likely to vary greatly between different individual estimates, and ultimately depends on the

type of model used and the source and nature of the underlying data. Using simulation

methods, it is feasible to quantify an uncertainty interval for each estimate that accounts for

confidence in the underlying epidemiological data as well as uncertainties associated with

the various assumptions and additional information used. Such an analysis has not been

possible in the time frame of this report, however, but may constitute the subject of future

research.

In the absence of such analyses, it is worth noting where major sources of uncertainty are

likely to lie in more qualitative terms. Among major causes of burden presented in this

report, uncertainty is probably highest for hearing loss, neurological conditions,

osteoarthritis and cirrhosis. The reasons for suspecting higher levels of uncertainty in these

conditions are discussed below.

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Hearing loss — although population data on measured hearing loss thresholds were used to

estimate disability for this condition, there was considerable uncertainty associated with the

modelling of the average durations associated with progressing from mild through moderate

to severe hearing loss and, to a lesser extent, the effect of hearing aids on reducing the

severity of disability from hearing loss.

Osteoarthritis — estimates for this condition were based on the same overseas studies of

incidence and severity used in the previous Australian Burden of Disease and Injury Study.

These estimates are lower than would be suggested by the Australian self-reported

population data on osteoarthritis. Considerable uncertainty remains about the true incidence

of this condition at the population level.

Selected neurological conditions — information on dementia and Parkinson’s disease came

from meta-analyses of international community-based studies of prevalence. For the

estimates presented in this report, these analyses were updated to include all such studies in

Western countries. There is uncertainty about the variations in the level of disease among

these countries.

Cirrhosis — there is no easy way to measure the prevalence of cirrhosis at a population

level. This report relied on a published modelling effort that projects the progression to

cirrhosis in people with hepatitis C. These figures were used to extrapolate cirrhosis from

hepatitis B, alcohol dependence and other causes. Considerable uncertainty surrounds these

extrapolations.

Mental disorders — these estimates were based on the mental health survey conducted in

1997; more recent data on this large cause of non-fatal burden would have been desirable.

Because of high levels of comorbidity between depression and anxiety, as well as the largely

similar treatment pathways, these conditions were combined into one entity and modelled

over a life course. This departs from the approach taken in the previous study where each

condition was treated separately and depression was modelled as an episodic condition.

General levels of uncertainty

In more general terms, it is likely that uncertainty in the estimates of burden presented in

this report may not be excessive. Overall, about half of the total burden in Australia was

attributable to mortality, for which estimates are fairly robust. Of the remainder, half was

attributable to non-fatal burden from a small number of diseases (including cardiovascular

disease, cancers, diabetes, common mental disorders, and injuries) for which reasonably

good Australian data are available. This leaves around a quarter of the total burden with

varying and probably higher levels of uncertainty.

What is clear is that a number of key estimates presented in this report are likely to be much

more accurate than those of the previous study. This is due to the availability of considerably

better quality data in some cases, one source of which deserves special mention. Access to

the linked hospital and mortality databases in Western Australia allowed greater accuracy in

the modelling of cardiovascular disease, the second leading cause of burden in Australia. As

Western Australia adds more health information data sets to its linkage program—including

health surveys, disease registries, Medicare and Pharmaceutical Benefits Scheme (PBS)

data—this will become an even more valuable resource, both for Western Australia and

nationally. Various efforts are in train to encourage data linkage in other jurisdictions and at

the national level. For example, the Statistical Information Management Committee (a multijurisdictional

committee established by health CEOs) has commissioned the development of

a framework for national data linkage, which takes careful account of such concerns as

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privacy, data protection, and custodianship. These efforts are to be encouraged, as they will

underpin improvements in future analyses of the burden of disease and injury in Australia.

Aside from data inputs, it is also worth mentioning the tools used. The second version of the

epidemiological modelling software DisMod allowed much more accurate modelling of

consistent epidemiological parameters than was possible in the previous study. In using this

software, particular attention was directed towards a consistent application of the concept of

‘excess risk’ (that is, people with a condition are often more at risk of dying than would be

indicated by the mortality actually coded to that condition) by accessing information from

international cohort studies and the linked hospital and death databases in Western

Australia.

DisMod also allows for past trends in incidence and case-fatality to be modelled, which is

particularly important for diseases with prevalence as the main observed parameter and for

which there have been significant trends in the past. This is because prevalence is a ‘stock’

variable and is simply a reflection of past trends in incidence and case-fatality. In this study,

there was a strong upward trend in the incidence of diabetes, accompanied by an

improvement in case-fatality. Ignoring these trends would have lead to an underestimate of

the true incidence of this disease. One area where DisMod was unable to help, however, was

in replicating final epidemiological models to multiple subpopulations and to various points

through time. For this application a custom-built routine was developed within a statistical

package environment based on DisMod’s underlying equations.

A final issue that is relevant to precision considerations is the set of disability weights

assigned to each health state. To date, a comprehensive set of weights has not been derived

in the Australian context. It was therefore necessary to continue to use an assortment of

weights derived largely from a Dutch study supplemented with weights from the original

Global Burden of Disease study and weights derived from a regression model on the Dutch

weights and the six domains of the EQ5D+ (an instrument to quantify quality of life).

Funding requested as part of the current study to validate these disability weights in the

Australian context has not been forthcoming. Also, internationally there has not been the

expected further development of measuring health state preferences to determine disability

weights. The large effort of collecting data in the World Health Surveys by the World Health

Organization in the first part of this decade has not yet resulted in any publication.

While this may raise concerns about the construct validity of the non-fatal estimates of

burden presented in this report, it should be noted that the rank order of weights for most

conditions has strong face validity and has been documented to be reasonably constant for a

set of ‘tracer conditions’ when replicated in different countries. Of greater concern are the

disability weights for common but low-severity conditions such as mild hearing loss, mild

vision loss, uncomplicated diabetes, asthma and anaemia. Existing health state evaluation

methods do not seem to accurately capture differences in severity between such conditions.

The lack of valid disability weights for distinguishing between high-prevalence low-severity

conditions is more important than it sounds because a small absolute difference in the

disability weight for a highly prevalent condition has a major bearing on the size of the

burden attributable to that condition. This is an area in need of further development.

Lastly, with respect to disability weights, a major improvement of this study compared with

most burden studies has been a comprehensive correction for coexisting health states. In the

previous study, an attempt was made to deal with comorbidities within mental disorders,

injuries and common causes of burden in the elderly, although each group was treated

separately and the latter was not comprehensive. Furthermore, the methods used assumed

no dependence between health states (that is, groups of conditions being more likely to

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coexist due to common causal pathways). The methods developed for the present study

drew upon multiple surveys and hospital data to derive probabilities of coexistence for all

possible combinations of health states that were modelled using an innovative

microsimulation approach. Dependence is implicitly accounted for in this approach.

Corrections for comorbidity in burden estimates are necessary because disability weights are

typically derived in isolation from each other, meaning that coexisting disability in the same

person is unlikely to be simply additive across two or more health states.

7.4 Access to data

Previous burden estimation work has been done mostly within a spreadsheet environment.

The benefits of this approach are that transparency and portability are maximised and, to

date, no other approach has achieved the level of flexibility afforded by working in this way.

However, accuracy can be a problem in that, in a spreadsheet, location is critical and

incorrect cell references are common. More importantly, spreadsheets rapidly become

unwieldy when more than several dimensions are being represented. In this study,

spreadsheets were retained for all basic disability modelling work, but a statistical package

environment was used for all subsequent analyses. The first practical implication of this

decision is that a set of spreadsheets containing all disability models exists and will be made

available to those who are interested. Users of this resource should note, however, that the

disability estimates in these spreadsheets will usually not correspond exactly with final

estimates in this report because comorbidity corrections and some trend corrections occur

outside this environment.

The other more interesting implication is that having extracted all relevant information from

the spreadsheets and derived final burden estimates outside this environment, the results

can be reassembled in any requested structure. This is particularly relevant for the estimates

for subpopulations and for various points through time. In collaboration with various

jurisdictional stakeholders, this information can be grouped into meaningful aggregations

for specific health policy and planning purposes. In addition, a web-based interface could be

developed whereby users could extract the desired information by cause, age, gender, time

and subpopulation. The website developed for disseminating the 1996 and 2001 Victorian

Burden of Disease study results is a useful model (see

<www.dhs.vic.gov.au/health/healthstatus/bod/bod_reg.htm>).

7.5 Future directions

This study comes seven years after the original Australian Burden of Disease and Injury

Study. It has taken three years to complete, with the equivalent of 2–3 full-time staff and

considerable intermittent assistance from researchers from several state health departments

and masters students. Such a commitment of resources to this type of research is unlikely to

occur again in this country in the short term. One of the aims of the study, therefore, was to

develop a less resource-intensive way of retaining an up-to-date set of burden estimates

going forward in time. To this end, a database of estimates for each year between 2003 and

2023 has been developed. This will provide an invaluable set of ‘base-level’ results for those

wanting to make assessments of burden in the period prior to the next major update. Such

assessments may entail varying levels of sophistication, from simple updates of fatal burden

using the most recent mortality data to ad hoc changes to specific non-fatal estimates based

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on advances in knowledge and better data. Through the adoption of strategies such as these,

a major revision may not be needed for at least another five years.

The final report of the previous Australian Burden of Disease and Injury Study identified

seven areas where it was felt priority should be placed in future research. Progress has been

made in a number of these areas over the last seven years, four of which are addressed

specifically by the present study. These include the development of burden estimates for

Indigenous Australians, a more detailed assessment of differentials in burden across

Australia, including estimates by socioeconomic status, remoteness and jurisdictional

boundaries, and more detailed modelling of National Health Priority Area diseases. A fifth

suggestion regarding the value of linking burden research to cost-effectiveness analyses has

been picked up in a number of separate studies around the country over this period.

Progress on two recommendations, however, has been less rapid. It has not been possible to

estimate and validate a set of disability weights in the Australian context and this remains an

important area requiring further development. Finally, there has been no formal evaluation

of the usefulness of burden of disease and injury analyses for policy makers and health

planners. There has been enough informal feedback from planners, researchers and the

media to know that there is consistent demand for this type of information. But a more

formal analysis of the impact on health assessment, policy and planning of this research over

the last seven years would be welcome.

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Appendix 1: Methods for estimating

disability burden

In this section we describe our methods for calculating disability for the large number of

diseases and injuries and their sequelae for which models were developed, including all

those that make significant contributions to the total non-fatal burden. While this list is

extensive, it is not exhaustive, and explicit models were not developed for many conditions.

Table A1.1 lists the full names of many of the data sources underlying our models and our

abbreviations of these names, which we use in this section for ease of reference.

Table A1.1: List of full and abbreviated names of commonly used data sources

Abbreviated name Full name

AusDiab The Australian Diabetes, Obesity and Lifestyle Study, 1999–2000 (Dunstan et al.

2001)

Australian dialysis and transplant data 2002 Australian and New Zealand Dialysis and Transplant Registry (McDonald &

Russ 2002). The interpretation of this data is the responsibility of the authors of this

report and should not be seen as the interpretation of the Australian and New Zealand

Dialysis and Transplant Registry.

Australian disability survey Survey of Disability, Ageing and Carers (1993, 1998 or 2003) (ABS 1993, 1998b,

2003b)

Australian general practitioner data 2000–01 and 2002–03 Bettering the Evaluation and Care of Health (AIHW: Britt et al.

2001)

Australian hospital data 2002–03 National hospital morbidity database (AIHW 2003a)

Australian mortality data 2003 Cause of Death dataset (ABS 2005)

Australian notification data National Notifiable Infectious Disease Surveillance System (CDA, 2003) except for

HIV/AIDS which is from the National Centre for HIV Epidemiology and Research

(National Centre in HIV Epidemiology and Clinical Research, 2003)

Australian perinatal data 2002 Australia’s mothers and babies and various state and territory perinatal data

collections (AIHW: Laws & Sullivan 2004; Queensland Health 2004; Riley & King

2003).

Disability weight regression model Regression model of Dutch disability weights which requires inputs of health state

description based on the six domains of the EQ5D+ (p. 158 of AIHW: Mathers et al.

1999)

DisMod DisMod version II (Barendregt et al. 2003)

GBD study Global burden of disease and risk factors, 2000 (Lopez et al. 2006)

Low prevalence study 1997–98 Low Prevalence (Psychotic) Disorders Study (Jablensky et al. 1999)

National Health Survey 2001 National Health Survey (unless otherwise specified as the 1995 National Health

Survey) (ABS 1995, 2001c)

National mental health survey 1997 National Survey of Mental Health and Wellbeing (ABS 1997)

National Trachoma Survey 1980 National Trachoma and Eye Health Program (Royal Australian College of

Ophthalmologists 1980)

Previous Australian burden study Australian Burden of Disease and Injury Study, 1996 (AIHW: Mathers et al. 1999)

Victorian birth defect data 2001–02 Victorian Birth Defects Register (Riley & Halliday 2004)

Victorian linked hospital dataset Analyses of Victorian hospital data 1996–2002 & 2001–02 from the 2001 Victorian

Burden of Disease and injury study (DHS, 2005)

Women’s health Australia Australian longitudinal study on women’s health (Lee et al. 2005)

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1A Infectious and parasitic diseases

Tuberculosis

We estimate the incidence of tuberculosis using Australian notification data on new cases of

tuberculosis. We assume that the average duration for tuberculosis is 8 months, reflecting 6

months for the shortest treatment cycle available and another 2 months of symptoms before

treatment.

Sexually transmitted diseases (excluding HIV/AIDS)

We base our incidence estimates for syphilis, chlamydia and gonorrhoea on Australian

notification data. Following expert advice, we assume that annual notifications for syphilis

and gonorrhoea represent all incident cases. We model syphilis using a staged approach

applying proportionate distributions for primary, secondary, and tertiary syphilis from the

GBD study. We adjust our estimates for chlamydia to account for under-reporting due to

asymptomatic infections and the reluctance of some patients to consult general practitioners

about sexually transmitted diseases. We base our incidence estimates of pelvic inflammatory

disease, a complication of both chlamydia and gonorrhoea in women, on Australian hospital

data. Following expert advice we adjust these estimates to account for under-identification.

Common sequelae of pelvic inflammatory disease include ectopic pregnancy, chronic pelvic

pain, infertility and tubo-ovarian abscess. We base our rates of complications following

pelvic inflammatory disease on GBD assumptions. We adjust our incident estimates of

infertility resulting from pelvic inflammatory disease for women who do not wish to have a

child and therefore do not experience disability. In the absence of Australian data on ‘child

wish’, we make this adjustment using findings from a recent German study (Stobel-Richter et

al. 2005). The GBD reports urethral stricture and epididymitis as complications following

chlamydial and gonorrhoeal urethritis in men. These complications were thought by experts

to be rare, and so have not been included in the Australian estimates. We model disability

weights and durations for syphilis, chlamydia and gonorrhoea and their sequelae using the

assumptions of the GBD study.

HIV/AIDS

We model HIV as a progressive condition with four stages: (1) asymptomatic HIV; (2)

symptomatic HIV; (3) AIDS prior to terminal phase; and (4) terminal AIDS. We assume that

the annual number of new HIV diagnoses from Australian notification data represent all

incident cases of HIV. We use the Dutch disability weights for each of the stages (stage

1—0.2, stage 2—0.31, stage 3—0.56 and stage 4—0.95) and adjust the weight for stage 1 to

account for the estimated proportion of undiagnosed asymptomatic HIV cases to whom we

assign a disability weight of 0 (Aalen et al. 1997). We calculate the mean durations for stages

1 to 3 using Weibull regressions of published data accounting for background mortality

(Kaldor & McDonald 2003; Mocroft et al. 1997; Porter et al. 2003). This gives average

durations of 30 years for the combined stages 1 and 2 and 5.5 years for stage 3. We adjust our

duration estimates for stage 1 and 2 based on the assumption that an equal amount of time is

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spent in each stage based on work by Aalen and colleagues (1997). In the absence of new

evidence, we assume that stage 4 lasts an average 0.5 of a year.

Diarrhoeal diseases

Diarrhoeal diseases include a number of notifiable diseases as well as non-notifiable

diseases. Given that notifications are generally considered a gross underestimate of the

incidence for notifiable diarrhoeal diseases, and that there is often even less reliable

information on the incidence of non-notifiable diarrhoeal diseases, we do not model

diarrhoeal diseases using notification data or by specific cause. Instead, we derive the

incidence of diarrhoea not requiring hospitalisation using annualised self-reported data from

the 2001–02 National Gastroenteritis Survey (Hall & OzFoodNet Working Group 2004). We

base our duration of 2 days from the findings of this survey and use age-specific weights for

uncomplicated diarrhoea (average weight of 0.093) from the GBD study. We use Australian

hospital data to estimate the incidence of diarrhoea cases requiring hospitalisation. We use

the age-specific GBD weight for diarrhoea (0.093) since the Dutch weight is implausible. We

assume 2 weeks duration for complicated diarrhoea and derive an average weight (0.42)

based on 1 week of disability equivalent to the regression model of health state (323311) and

1 week of disability for uncomplicated diarrhoea.

Childhood immunisable diseases

We do not model poliomyelitis and diphtheria for 2003. This is because there were no

notifications of poliomyelitis from 1993 to 2003 and only one notification of diphtheria in

2001.

Pertussis

We estimate the incidence of pertussis using Australian notification data averaged over

2000–2003, an epidemic cycle. We adjust our incidence estimates for under-reporting based

on the literature (Andrews et al. 1997; Torvaldsen et al. 2002). We apply the age-specific GBD

disability weights for untreated cases for pertussis (0–4 years: 0.178; 5–14 years: 0.166; 15

years or over: 0.156), since the weight for treated cases is implausible, along with the GBD

duration of 1 month. Following expert advice we estimate the incidence of intellectual

disability attributable to pertussis as the proportion of intellectual disability cases from the

total episodes of infection for 0–4 year olds in the GBD study (that is, 0.3% of pertussis cases).

We derive a disability weight (0.58) for pertussis-related intellectual disability by weighting

the number of cases of intellectual disability due to infectious diseases by the level of severity

(using the Dutch weights for intellectual disability).

Tetanus

We estimate the incidence of tetanus using Australian notification data and apply the GBD

disability weight for 60 years or over of 0.612, and duration of 2 weeks.

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Measles

We derive the incidence of measles using Australian notification data. We assume annual

notifications in 2003 represent all cases of measles due to enhanced surveillance (Brotherton

et al. 2004). For acute measles episodes we apply the GBD duration and disability weights (2

weeks, 0.152). We use Australian hospital data to estimate the incidence of measles sequelae.

In 2003 there were no hospitalisations for measles encephalitis, and only one for sub-acute

sclerosing panencephalitis. For the latter sequelae we apply the Dutch disability weight for

end stage disease with a duration of 9 months.

Rubella

We derive the incidence of rubella using Australian notification data which we adjust for

over-reporting. Enhanced surveillance of rubella notifications in Victoria found that 27%

were laboratory confirmed (Guy et al. 2004). As there is no GBD or Dutch weight for rubella

we use the measles disability weight (0.152) with a duration of one week. We use Australian

notification data to derive incidence estimates of congenital defects due to rubella; there were

only three such cases in 2003. The classic triad of complications associated with congenital

rubella infection are cataract, heart disease, and deafness. In the absence of more specific

information, we derive an average disability weight and durations to reflect each of these

complications.

Haemophilus influenzae type b

We derive the incidence of Haemophilus influenzae type b from Australian notification data.

We only model the disability associated with the following sequelae—meningitis,

epiglottitis, septicaemia, pneumonia and ‘other’ using data from an Australian study (Herceg

1997). Following expert advice we assume that all cases of epiglottitis and meningitis are

confined to the 0–14 year age group and pneumonia and septicaemia to the 15 years or older

age group. We assume that meningitis from Haemophilus influenzae type b is included in the

hospitalisation-based estimates of total meningitis and subtract these cases from the total

incidence estimates of meningitis to avoid double-counting. We use the same disability

weights and durations for these sequelae as per the previous Australian burden study.

Meningitis

We estimate the incidence of meningitis from Australian hospital data which we adjust to

avoid double-counting of meningitis from Haemophilus influenzae type b. We model

meningitis as a progressive condition with acute episodes of one month, after effects lasting

up to six months and subsequent lifelong effects, in some, for a range of conditions

(including hearing loss, ventriculoperitoneal shunt, seizure disorder, less severe

developmental problems, mental retardation and motor deficit and physical deformities).

We make minor modifications to the assumptions in the Dutch study regarding proportions

of meningitis cases progressing to sequelae and their associated disability using the results of

a seven-year follow-up study of meningitis in Melbourne children (Grimwood et al. 1995)

and expert opinion.

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Septicaemia

We estimate incident cases of septicaemia from Australian hospital data. We do not adjust

our estimates to account for meningitis-related septicaemia as Victorian data suggests that

less than 2% of cases are due to meningitis. In the absence of a weight for this condition in its

uncomplicated state, we use the Dutch weight for meningitis for an average duration of 1

month (Stouthard et al. 1997).

Arbovirus infections

We estimate the incidence of arbovirus infections using Australian notification data. Because

there are no specific disability weights for arboviruses we use comparable weights from the

Dutch study. For Ross River and Barmah Forest viruses we adjust estimates by 100% to

account for under-reporting in endemic areas. We model Ross River and Barmah Forest

viruses as a febrile illness in children aged up to 14 years and as an illness with acute and

chronic stages for incident cases aged 15 years or over. Based on Australian literature we use

the Dutch weight for influenza for children (1 month duration) and the Dutch weights for

moderate rheumatoid arthritis (1 month duration) and mild arthritis (3.5 months in Ross

River fever and half of this duration for Barmah Forest virus) for acute and chronic stages

respectively in adults (Mylonas et al. 2002; Russell 2002). In general, arthralgia persists

longer in Ross River virus infection than in Barmah Forest virus infection (Mackenzie et al.

1998; Russell & Dwyer 2000), therefore we halve the duration of the chronic phase in the

latter.

We adjust notifications for dengue fever by 10% to account for under-reporting. Based on the

literature we use the Dutch weight for malaria with a duration of 6 days (Russell & Doggett

1998; Solomon & Mallewa 2001). We use Australian hospital data to estimate the incidence of

the rare and disabling sequelae dengue haemorrhagic fever. There were only two cases in

2003. The GBD weight for this condition appears too low and so we apply the Dutch weight

for meningitis for just over 1 week.

We model the following flavivirus infections as ‘other arbovirus infections’: Murray Valley

encephalitis, Kunjin virus infection, Japanese encephalitis, and flavivirus not elsewhere

classified. In 2003 there were no notifications for Murray Valley encephalitis and only one

case of Japanese encephalitis notified. We apply GDB estimates of the incidence of sequelae

(episodes, cognitive impairment and neurologic sequelae), average disability weights, and

duration for Japanese encephalitis to all other arbovirus infections.

Hepatitis

Hepatitis A

We estimate the total incidence of hepatitis A using Australian notification data, which we

adjust for under-reporting (Amin et al. 1999). We assume that the 10% of incident cases

represent prolonged hepatitis A. We assume that Australian hospital data on hepatitis A

represent all cases of complicated hepatitis A. We calculate the number of incident cases of

uncomplicated hepatitis A by deducting the prolonged and complicated cases from our total

estimate. Due to the implausibility of the Dutch weight for uncomplicated hepatitis A we use

the average GBD weight of 0.093 with a duration of 3 weeks (Amin et al. 1999). We assume

that prolonged hepatitis A cases experience depression or fatigue for 6 months at disability

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weight equivalent to the Dutch weight for mild depression (0.14) (McIntyre 1990; Willner et

al. 1998). We assume durations of 4 weeks for children and 6 weeks for adults (Melnick

1995). We apply a severe disability weight for half of this time (DW 0.747), and the remaining

time at the same weight as uncomplicated cases. This gives an average weight of 0.42.

Hepatitis B

We estimate the incidence of acute hepatitis B using Australian notification data and assume

that all infections reported as incident are symptomatic.

We derive incidence estimates for acute symptomatic hepatitis B infection in infants from

birth data and probabilities of perinatal transmission for ‘at risk’ mothers as reported by

Kaldor and colleagues (1996). Based on the literature we assume a 40% probability of

transmission if exposed. Using this estimate we can calculate the number of infants who

would be infected in the absence of vaccination (Kaldor et al. 1996). As current vaccination

coverage in children born to mothers ‘at risk’ is 95% (Menzies et al. 2004), we reduce the

number of carriers from perinatal transmission accordingly. Similarly we adjust the number

of perinatal infections for the probability of symptomatic infection which is 5% (Kaldor et al.

1996). Based on expert opinion, we assume a similar number of infections by casual contact

in childhood and for males and females.

We base our estimates of chronic hepatitis B on a series of DisMod models. First we estimate

the prevalence of adult carriers using an overall prevalence of 0.47% (O’Sullivan et al. 2004),

a remission of 0.5%, and an overall relative risk of mortality of 1.5. Next we estimate the

prevalence of adult carriers using incidence estimates of carriers from perinatal and casual

childhood transmission assuming no vaccination had occurred. We then subtract the

prevalence of carriers from childhood infections from the first model so we can use DisMod

to derive the incidence of chronic hepatitis B infection in adults. This model assumes a

steady state of hepatitis B infection in the population, with vaccination only recently

affecting perinatal and childhood transmission rates. This is unlikely to reflect the pattern of

disease over time, but in the absence of data on the trends over time, this was considered the

most plausible method of modelling the disease following expert consultation.

We assume the average duration for an acute symptomatic episode to be 4 weeks (Lee 1997).

We use the Dutch disability weight for acute hepatitis infection (0.21). We adjust the Dutch

weight for chronic hepatitis B infection with active viral replication (0.36) following expert

advice that only 15% of chronic cases have a symptomatic episode for 2 weeks each year

(giving an average weight of 0.002). The methods we use to derive YLD for

hepatitis B-related cirrhosis and liver cancer are described in the following section on

hepatitis C. test

Hepatitis C

Due to the asymptomatic nature of hepatitis C infection we assume that all YLD are a result

of hepatitis C sequelae, that is, cirrhosis and liver cancer.

There is a paucity of information on the occurrence of cirrhosis at a population level. Instead,

we make use of estimates of hepatitis C-related cirrhosis occurrence from an Australian

study which modelled the progression rates to various sequelae from hepatitis C incidence

(Law et al. 2003). The major problem in estimating the occurrence of hepatitis C-related

cirrhosis is the dramatic change in hepatitis C incidence over the last 5 decades, the relevant

time period for the development of current cirrhosis cases. The best available approximation

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of the pattern of hepatitis C epidemiology over the last 40 years is based on the pattern of

injecting drug use over time (Law et al. 2003).

We make largely the same assumptions in the modelling of hepatitis C-related cirrhosis as in

Law and colleagues (2003):

• 75% of people exposed to hepatitis C develop chronic infection

• an annual progression rate of 2% to cirrhosis

• a hepatitis C-related mortality rate of 1.5% following cirrhosis

• mean age of hepatitis C seroconversion among injecting drug users of 25 years

• a male to female ratio of 2:1 for persons who inject drugs and are hepatitis C-infected

• unlike in Law et al. (2003), we assume that 80% of those exposed to the hepatitis C (the

estimated proportion of hepatitis C carriers exposed through injecting drug use) have a

relative risk of mortality of 13 (Darke & Ross 2002) for an average of 14 years from the

moment of exposure (as estimated for heroin dependence)

• background mortality is calculated from life tables constructed from Australian

mortality and population data from 1950 to 2003.

Based on this model, we estimate 447 new cases of hepatitis C-related cirrhosis and 5,804

people living with cirrhosis due to hepatitis C in 2003. Next, we examine the Australian

hospital data for cirrhosis. In all cases in 2003 with a stated underlying cause, 49.4% are

alcohol related and 50.6% non-alcohol related. Based on expert opinion we attribute 5% of

non-alcohol related cirrhosis to other causes and the remainder to hepatitis. We estimate the

occurrence of cirrhosis due to other causes (that is, hepatitis B, alcohol abuse, and ‘other’) by

adjusting Australian hospital data by the admissions-to-prevalence ratio observed in

hepatitis C-related cirrhosis cases. We only give a disability weight for the last 3 years lived

with cirrhosis at 0.31 (minus 2 months) and 0.84 for the last 2 months (effectively interpreting

the Dutch weight for compensated cirrhosis as relevant for the time spent in decompensated

cirrhosis and the decompensated cirrhosis weight of the Dutch as the weight for terminal

liver failure).

In the previous study we assumed liver cancer occurred in around 19% of people with

hepatitis C and hepatitis B. More recent data, including from a large multi-centre study of

liver cancer patients in Europe, indicates that hepatitis B and C are responsible for around

19% and 40% of liver cancer respectively (Brechot et al. 1998; CDC 2001).

Malaria

We derive incidence estimates for malaria from Australian notification data. We model two

aspects of malaria, episodes and neurologic sequelae and adopt GBD assumptions for

disability weights and durations.

Trachoma

We model the disability associated with mild, moderate and severe vision impairment

resulting from trachoma infection. We assume that trachoma related visual impairment is a

problem only in remote Australia. We estimate the prevalence of trachoma-related visual

impairment using the 1980 National Trachoma and Eye Health Program. Based on expert

advice we adjust the prevalence downwards by one-third to account for observed decreases

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in the prevalence of scarring stages that follow infectious trachoma since the national survey

was conducted (Landers et al. 2005; Mak & Plant 2001). In the absence of more specific

information we assume that mild and moderate vision loss have the same cause distribution

by age as severe vision loss. We make minor adjustments to the prevalence of each stage by

age to ensure plausibility and to reflect published estimates. We estimate the incidence and

duration of trachoma in DisMod using our derived prevalence estimates. We initially model

the prevalence of severe vision loss in DisMod assuming no remission and a relative risk of

mortality of 1. We then use the incidence of severe vision loss from the DisMod output as

‘mortality’ in the moderate vision loss DisMod model. This takes the cases of severe vision

loss out of the pool of susceptible cases for moderate vision loss and therefore gives more

accurate average durations than if we were to use remission as remitted cases in the DisMod

model, as the cases continue to be subject to the hazard of incidence. Similarly we use the

incidence of moderate vision loss as ‘mortality’ in mild vision loss.

1B Acute respiratory infections

Lower respiratory tract infections

We base our incidence estimates for lower respiratory tract infections, including episodes of

influenza, acute bronchitis and pneumonia, on Australian general practitioner data. For

pneumonia, general practitioner data was thought to be more representative than hospital

data as it should include those who do and do not go to hospital. We use the same

assumptions for disability and durations as in the previous Australian burden study. GBD

duration estimates were halved to 3.5 days for acute bronchitis, and left at 1 and 2 weeks

respectively for influenza and pneumonia. Disability weights were derived using the

regression model (influenza 0.047; acute bronchitis 0.132; pneumonia 0.373).

Upper respiratory tract infections

We base our incidence estimates for episodes of acute nasopharyngitis and acute sinusitis on

annualised self-report data from the National Health Survey, while we model tonsillitis and

pharyngitis using Australian general practitioner data. We use the data from the 1995

National Health Survey because the 2001 survey did not include questions on acute

conditions. We adjust the tonsillitis and pharyngitis incidence estimate upwards by twofold

to reflect the much higher rate (13 times) for the broader condition of ‘sore throat’ that was

reported in the survey. We use derived weights and assume GBD durations, with minor

adjustments where we consider this to be appropriate. For employed adults, the average

number of days off work due to upper respiratory tract infections was around 0.5 of a day.

The GBD assumed an average duration of 3.5 days. The self-report prevalence data probably

includes a considerable number of minor infections with minimal disability. Hence we use

days off work plus half a day on either side to give an average duration of 1.5 days for acute

nasopharyngitis. For tonsillitis and pharyngitis and sinusitis we use the GDB durations of

3.5 days.

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Otitis media

We model the following stages of otitis media; acute infection, bilateral chronic infection, and

life-long deafness. We estimate the incidence of acute episodes using Australian general

practitioner data. We assume that those who have relatively low disability do not seek

treatment and base YLD estimates on treated numbers. We adjust our incidence estimates to

allow for a higher rate of acute otitis media in Indigenous Australians in remote areas based

on findings from the 1980 National Trachoma and Eye Health Program. We use the disability

weight regression model to derive an appropriate weight (0.090) and assume a duration of

1 week.

We estimate the prevalence of chronic otitis media in non-Indigenous and Indigenous

Australians from the National Health Survey for those people reporting otitis media as a

long-term health problem. We assume that these estimates represent non-Indigenous

Australians in all areas and Indigenous Australians in major city or regional areas. We adjust

these prevalence estimates downwards to account only for bilateral cases using a ratio of

bilateral to unilateral cases from the 1980 National Trachoma survey. We estimate the

prevalence of bilateral chronic otitis media in Indigenous Australians in remote areas from

the 1980 National Trachoma survey and assume that the epidemiology of bilateral chronic

otitis media has not changed since the survey was undertaken. We derive the incidence and

duration of bilateral chronic otitis media in DisMod using prevalence, a relative risk of 1 and

remissions equivalent to durations of 3 months and 3 years for non-Indigenous and

Indigenous Australians, respectively, based on Australian data (McGilchrist & Hills 1986).

We base our estimates for permanent hearing loss resulting from acute infections on the GBD

study. For chronic infection we apply the Dutch weight for early acquired mild to moderate

hearing loss (0.110). For the small number of cases that experience lifelong deafness, we use

the Dutch weight for early acquired severe hearing loss (0.233).

1C Maternal conditions

We base our incidence estimates for maternal haemorrhage, maternal sepsis, hypertension in

pregnancy, obstructed labour, abortion and other maternal conditions on Australian hospital

data. We adopt GBD methods except in the following instances. On expert advice we assume

hypertension in pregnancy results in restricted activity (due to advised bed rest or

hospitalisation) for 2 months at a derived weight of 0.117 (health state 122111), with 1 in

2,500 cases developing neurological sequelae. We model the sequela caesarean section with

2 weeks of disability at a derived weight of 0.349 (health state 222111). We base our incidence

estimates for abortions using South Australian data on terminations of pregnancy as a

proportion of total births (Chan et al. 2003). For abortion we model the disability of infertility

resulting from the sequela pelvic inflammatory disease. We assume that 20% of hospitalised

cases of pelvic inflammatory disease following abortion experience infertility from age at

infection to post-reproductive age which we assume to be 45 years. We adjust our incident

estimates of infertility, in the abortion and maternal sepsis models, for women who do not

wish to have a child and who therefore do not experience disability. In the absence of

Australian data on ‘child wish’, we make this adjustment using findings from a recent

German study (Stobel-Richter et al. 2005). Although stress incontinence was considered a

sequela of obstructed labour in the GBD study, most stress incontinence occurs in the

absence of such a history. We therefore treat this condition as a category in its own right,

classified under ‘genitourinary conditions’.

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1D Neonatal causes

Birth trauma and asphyxia

We estimate the incidence of mild, moderate and severe birth asphyxia using Australian

hospital data. We separate the mild and moderate incident cases using data from the GBD

study. We base our sequela estimates of neurological disability by severity of birth asphyxia

(0% of mild, 25% of moderate and 100% of severe) on the GBD study.

We use the estimates of intellectual disability due to birth trauma from the overall

calculations for intellectual disability by all underlying causes (see Section 2K). Stanley and

colleagues (1995) estimated that 8% of cerebral palsy is associated with birth trauma. The

balance of the incident cases of permanent disability is divided equally between deafness

and seizures.

We assume that the duration of cerebral palsy without intellectual disability and severe

hearing loss is the same as those with mild intellectual disability. We base the duration of

seizure on life expectancy at birth assuming a twofold risk of dying to indicate a greater

likelihood of premature mortality.

Low birth weight

We estimate the incidence of low birth weight (>=1500g and <2500g) and very low birth

weight (<1500g) in neonatal survivors using Australian perinatal data. We apply the sex

distribution of low birth weight from the 2002 Victorian perinatal data to the Australian

combined proportion for both sexes which we then apply to the total number of live births in

Australia in 2003 (ABS 2004). We adjust our estimates of total neonatal deaths in 2003 (ABS

2005) using a proportion for those due to low birth weight. This was derived using an

average of 2002 Victorian, Queensland, and South Australian data.

We assume the probability of disability among low birth weight survivors is 25% for very

low birth weight (<1500g) and 5% for low birth weight (>=1500g and <2500g) as per the GBD

study. This corresponds to a total of 1,230 incident cases (596 males, 634 females) of disability

in low birth weight survivors in 2003.

For hearing loss, vision loss, epilepsy, and other disability we distribute the incident cases of

disability in low birth weight survivors to disability type from the GBD study. We use the

estimates of intellectual disability due to low birth weight from the overall estimates of

intellectual disability (see Section 2K). In addition we attribute 60% of total incident cerebral

palsy cases (at 2.25 per 1,000 live births) to low birth weight.

Just over one half of the low birth weight survivors with permanent disability do not have

severe neuro-developmental disability. In the absence of a defined disability weight for this

health state we assume that these cases have a level of disability similar to the Dutch weight

for permanent early childhood acquired moderate hearing loss. For all other sequelae we

apply the relevant Dutch disability weight.

We assume the duration of cerebral palsy without intellectual disability, severe hearing loss,

moderate vision loss, and mild permanent disability to be the same as those with mild

intellectual disability. We base the duration of epilepsy on life expectancy at birth assuming

a twofold risk of dying as compared to the mortality rates of the general population.

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Neonatal infections

We estimate the incidence of neonatal infections from Australian hospital data. We assume

1 month of acute disability using the Dutch weight of 0.894 (same as for meningitis) for acute

episodes.

The main long-term sequelae are deafness, motor deficit disability and intellectual disability.

We estimate intellectual disability attributable to neonatal infections as part of overall

estimates for all causes of intellectual disability (see Section 2K).

Other conditions arising in the perinatal period

Here we include YLD for intellectual disability due to other conditions arising in the

perinatal period.

1E Nutritional deficiencies

Iron deficiency anaemia

We model the following levels of severity for iron deficiency: non-anaemic, mild anaemia,

moderate anaemia and severe anaemia. We define anaemia in terms of blood haemoglobin

levels as per the GBD study. We derive our incidence estimates for iron deficiency anaemia

using DisMod. We base our prevalence estimates for mild, moderate and severe anaemia for

men and women aged 25 years and above from AusDiab. For the younger ages we use a

variety of Australian studies, assuming 60% of cases are mild and the remaining 40%

moderate (English & Bennett 1990; Karr et al. 1996; Nguyen et al. 2004; Oti-Boateng et al.

1998; Sadler 1996;). Iron deficiency causes anaemia but people can be iron-deficient and not

anaemic and vice versa. To calculate iron deficiency without anaemia, we first have to

estimate the prevalence of total iron deficiency which includes those with and without

anaemia. We assume prevalence estimates of 10% and 1% in children aged 0–4 years and

5–14 years respectively (English & Bennett 1990; Mira et al. 1996; Oti-Boateng et al. 1998;

Rangan et al. 1998; Ranmuthugala et al. 1998; Sadler 1996), with figures for other ages taken

directly from 1989 National Risk Factor Prevalence Survey—Iron status study. In the absence

of population data on the overlap between iron-deficiency and anaemia, we assume half the

cases with mild anaemia and all cases with moderate anaemia are also iron-deficient. For

adults aged 15 years or over, we subtract the prevalence of iron deficiency combined with

anaemia from the total prevalence of iron deficiency to avoid double-counting the disability.

We use the same assumptions for disability and duration as in the previous Australian

burden study.

2F Malignant neoplasms

As in the previous study, the basis of YLD estimation for malignant neoplasms is a series of

models of disease progression developed by the Dutch burden of disease study team for

26 cancers for which they determined disability weights (Stouthard et al. 1997).

The disease model commences with an initial phase of diagnosis and primary therapy, with

a duration of up to 12 months. After this, cases are classified as those who will and will not

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be cured. Those who will be cured enter a phase of up to 5 years after which they are

considered cured and have (with some exceptions as discussed below) no further cancerrelated

disability. Those who will not be cured enter a phase (of variable length) of remission

followed by a phase of disseminated carcinoma (lasting 12 months or less), then a terminal

phase (lasting 1 month) and death.

We allocate a Dutch weight to each of these phases. Where no Dutch weights were available

for a specific cancer site, we extrapolate weights based on the cancer that it most resembles.

The Dutch study did not derive a weight for the terminal phase of any of the cancers, so we

use instead the Dutch weight for general end-stage disease.

We modify this general model to each cancer site with results from studies in the peerreviewed

literature and input from local clinicians to reflect local treatment practices.

Disease incidence data

The primary source of cancer incidence data is the AIHW & AACR National Cancer Statistics

Clearing House database (AIHW & AACR 2001). This database records all cancer cases

(except non-melanoma skin cancer) notified in Australia from 1982 to 2001. Cancer incidence

rates in the Australian population change very slowly (AIHW et al. 2005). We apply the 2001

age- and sex-specific cancer incidence rates to the 2003 Australian population counts to

estimate the 2003 cancer incidence.

Two exceptions to this approach are breast cancer and non melanoma skin cancer. The breast

cancer disease model requires details of size of tumour at diagnosis which are not available

from the Clearing House database. Instead, we extrapolate the proportion of new cases in

each size category from 2001 BreastScreen Australia data (AIHW 2005a) and all incident

cases from the AIHW breast cancer size and nodal status report for 1997 (AIHW et al. 2001).

We then apply these proportions to the 2003 incident cases projected from the Clearing

House database. Non-melanoma skin cancer is not a notifiable disease in Australia and so is

not within the scope of the Clearing House database. Instead, we extrapolate the incidence

from the results of a 2002 Australian population survey of the incidence of non-melanoma

skin cancer (NCCI 2003).

Cure rate and mean survival time

To estimate the cure rate and mean time to death for those not cured for each cancer we

assume a Weibull distribution for the time from diagnosis to death and apply a non-linear

model to the survival curves for each cancer (Verdecchia et al. 1998). We base the survival

curves on all cases recorded in the Clearing House database with a diagnosis date between

1982 and 1997 which we follow-up for death until the end of 1999 (AIHW & AACR 2001).

We base the durations of the initial treatment, disseminated and terminal stages separately

for each cancer, using Dutch study assumptions, peer-reviewed literature and input from

local clinicians. For those not cured, we base duration of the remission stage as the total

average time to death (estimated from the Weibull model) less the sum of the other stages.

For those cured, we base the duration of the stage following initial treatment as 5 years less

the duration of the initial treatment stage.

Again, breast cancer and non melanoma skin cancer are the two exceptions to this approach.

Since the Clearing House database does not record tumour size, we base the survival times

and cure rates on an analysis of breast cancer cases by tumour size published by the South

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Australian Cancer Registry (South Australian Cancer Registry 2000). Because there are no

national data on non melanoma skin cancer we estimate survival times and cure rates using

assumptions modelled from published studies.

Long-term sequelae of cancer

The model for cancer in the previous Australian burden study assumed, with the exception

of bone cancer, that cancer sufferers have no further burden following cancer cure. However,

there are some cancers that are likely to have major sequelae causing long-term burden

following successful treatment. The GBD study included long-term sequelae for colorectal

cancer, breast cancer, female reproductive cancers and male genitourinary cancers. In

addition, we include removal of one eye for eye cancer, removal of the larynx for larynx

cancer, amputation for bone cancer and long-term brain injury for brain cancer. These

sequelae and their associated severity weights are listed in the table below (Table A1.2).

We estimate cancer-related rates of amputation, stoma, mastectomy, larynx, eye removal and

infertility from Australian hospital data. We estimate infertility rates from cancer-related

hysterectomies and assume these only apply to survivors under 40 years of age. We derive

impotence and incontinence rates from a review of the literature. Results published in the

literature note the similarity between the effects of treatment for brain cancer and other

forms of traumatic head injury, so we assume that the rates of long-term brain injury from

brain cancers are the same as the equivalent rates for head injury.

We use the GBD disability weights for stoma, mastectomy, infertility, impotence and

incontinence. For the disability associated with removal of an eye, amputation, and longterm

brain injury we use comparable weights from the Australian study for long-term

weight for an injury to an eye, major amputation and long-term effects of a brain injury in a

non-fatal accident or injury, respectively. For removal of the larynx we assume that the

Dutch weight for mild hearing loss, which is defined as ‘some difficulty in actively

participating in a conversation with one or more persons’, is appropriate.

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Table A1.2: Extra sequelae for cancer model

Site/sequelae Proportion of survivors with sequelae (%) Severity weight

Colorectal cancer—stoma 0.09 0.21

Bone & connective tissue—amputation 0.08 0.30

Breast cancer—mastectomy 0.51 0.09

Female reproductive cancer—infertility

Cervix: 0.46

Uterus: 1.00

Ovary: 0.64

0.18

(ages under 40)

Male genitourinary cancer—impotence

and incontinence

Prostate: 0.53

Bladder: 0.12 0.20

Brain cancer—long-term brain injury 0.05 0.35

Eye cancer—removal of an eye 0.45 0.30

Larynx cancer—removal of the larynx 0.35 0.04

2G Other neoplasms

Benign neoplasms are not notifiable in Australia. As a result we base our incidence estimates

for uterine myoma and benign brain tumour on Australian hospital data.

Specifically, for uterine myoma we use the numbers of myomectomies and hysterectomies

for fibroids. We assume that surgical treatment is undertaken for all cases of rapidly growing

or large tumours and myoma-related symptoms. We assume a six month pre-operative state

equivalent to the GBD weight for chronic pelvic pain and an additional three-week postoperative

state equivalent to laparotomy (derived weight of 0.349 for health state 222211).

Based on expert advice, we assume reproductive disability occurs in 3% of hysterectomy

cases to whom we apply the GBD weight for infertility. We assume the additional burden

associated with menorrhagia in undiagnosed women is included in our YLD estimates for

this condition under the ’other genitourinary’ category.

Our model for benign brain tumour is based on the model for malignant brain tumours

where we model the disease in stages for survivors (diagnosis and initial treatment, and

post-curative treatment) and non-survivors (diagnosis and initial treatment, pre-terminal

and terminal). We adjust our incidence estimates on the assumption that 20% of

hospitalisations are readmissions (Jaaskelainen 1986; Simoca et al. 1994). We base our

survival estimates on Australian mortality data and assume successfully treated cases

recover normal efficiency (Steiner et al. 1998) with a period of ‘worry’ after treatment of

2 years. In the absence of specific disability weights, we use those for malignant brain

tumours.

2H Diabetes

Diabetes cases

We estimate the incidence of insulin dependent diabetes mellitus (Type 1) from the National

Diabetes Register (AIHW 2003b). We use DisMod to estimate prevalence and duration,

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assuming no remission and age-specific risks of dying for all diabetes from the Asia Pacific

Cohort Studies Collaboration — a meta-analysis of 24 cohort studies from Asia, Australia,

and New Zealand that assessed the effects of diabetes on the risks of major cardiovascular

disease and death (Woodward et al. 2003). We estimate the incidence of non-insulin

dependent diabetes mellitus (Type 2) for ages less than 25 years from the National Diabetes

Register. We estimate the incidence of Type 2 diabetes for ages 25 years and above by

subtracting the prevalence of Type 1 diabetes from the total prevalence of diabetes from

AusDiab and then deriving incidence and duration in DisMod including an annual trend for

the period 1980–1999 for incidence of 2.5% for males and 1.5% for females (Dunstan et al.

2002). There is no direct measurement of the trend in incidence/prevalence of Type 2

diabetes in Australia. Instead, we analyse the historical trend in diabetes mortality (which is

relatively ‘flat’) and assume that this reflects the net effect of an increase in incidence and a

decrease in case-fatality which in turn we assume to be equivalent to the trend in

cardiovascular disease case-fatality (as the main causes of death in people with diabetes are

of cardiovascular origin). Thus, we also incorporate a 20 year trend for the case-fatality rate

(–2% annual for males and –1% for females). We then project incidence and case-fatality

forward to the year 2003 using the same trends as above and enter these into a DisMod

model for total diabetes for 2003.

We subtract out those with diabetic nephropathy to avoid double-counting as the Dutch

disability weight for diabetic nephropathy includes the disability associated with diabetes

per se. We use the Dutch disability weight for an uncomplicated diabetes case (0.070).

Complications from diabetes for which we calculate YLD include retinopathy, cataract,

glaucoma, renal failure, neuropathy, peripheral vascular disease, diabetic foot, amputations,

ischaemic heart disease and stroke.

Retinopathy

We estimate the prevalence of mild and moderate vision loss from proliferative diabetic

retinopathy in the Melbourne Visual Impairment Project (Weih et al. 2000). Experts

confirmed that most retinopathy is treated before it leads to more serious vision loss.

Therefore we estimate the incidence and duration of diabetic retinopathy in DisMod from

the prevalence estimates from the Melbourne project, assuming no remission and twice the

excess risk of mortality as for all diabetes. We base the proportion of cases due to Type 1 and

Type 2 diabetes on the ratio of expected cases derived from modelling data on the

progression of proliferative diabetic retinopathy from time of diagnosis (NHMRC 1997b;

Tapp et al. 2003b). The Dutch disability weights for mild and moderate vision loss apply.

Cataract and glaucoma

We estimate the proportion of YLD from cataract and glaucoma attributable to Type 1 and

Type 2 diabetes using population attributable fractions. We base the risks of cataract and

glaucoma in diabetics from the Blue Mountain Eye Study (Mitchell et al. 1997) and use

severity distributions from the Melbourne Visual Impairment Project (Weih et al. 2000).

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Renal failure

We estimate the incidence of diabetes-related renal failure using 2002 data from the

Australian dialysis and transplant data. We use DisMod to estimate the average duration for

people on dialysis, assuming a case-fatality rate reflecting observed deaths from the register.

We base our annual remission estimates on observed transplant data: 85% in Type 1

diabetes cases aged 0–85 years or over for males and females combined; 6% in Type 2 cases

under 65 years for males and females combined; and 0% in Type 2 cases aged 65 years or

over for males and females combined. We use the Dutch disability weight for diabetic

nephropathy (0.29). We estimate YLD for transplant patients assuming a case-fatality ratio

reflecting observed deaths from the register and 3% ‘remission’ due to graft failure (as these

patients return back to the pool of dialysis cases). We assume a high disability weight (0.29)

for the first 6 months following the transplant and a GBD weight of 0.11 thereafter.

Neuropathy

Tapp and colleagues provide estimates of diabetic neuropathy prevalence by time since

diagnosis (2003a). We estimate by linear regression an annual increment in prevalence,

which we then apply to survivors of incident cases of Type 1 and Type 2 diabetes by age as

they progress to other age groups. Based on the Rochester Diabetic Neuropathy Study only

15% of Type 1 and 13% of Type 2 cases with diabetic neuropathy are symptomatic, of which

6% of Type 1 and 1% of Type 2 are severely affected (Dyck et al. 1993). The disability weight

for Type 1 is 0.099 using the disability weight regression model (health state: 111111—85%;

222221—9%; and 222331—6%) and for Type 2 is 0.074 (using the corresponding percentages

of 87%, 12% and 1%).

Peripheral vascular disease

Tapp and colleagues provide estimates of peripheral vascular disease incidence and

prevalence (Tapp et al. 2003a). We assume that only those with claudication are

symptomatic. We estimate by linear regression an annual increment in the prevalence of

diabetes-related peripheral vascular disease in order to derive incidence, similar to the

approach for diabetic retinopathy. In the absence of Dutch or GBD disability weights for this

condition we derive a weight of 0.19 using the disability weight regression model. Remission

from surgery by vascular grafts is assumed to be 20%.

Amputation and diabetic foot

We estimate the incidence of diabetes-related amputations from Australian hospital data. We

use GBD disability weights for these conditions and base our durations and proportions

treated on expert opinion. We use amputation rate data for diabetics with foot ulcers from

the Diabetes Research Foundation (Yue & Molyneaux 2005). From 1994–2005 the amputation

rate for diabetics with foot ulcers was 5.3%. We calculate an average duration of 8.9 months

after fitting a log normal function to follow-up data on the duration of foot ulcers. As there is

no Dutch disability weight, we apply the GBD weight of 0.113.

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Ischaemic heart disease and stroke

We estimate the proportion of ischaemic heart disease YLD attributable to Type 1 and Type 2

diabetes using a population attributable fraction based on prevalence and the relative risk

(2.0 and 2.5 for males and females respectively) of dying from ischaemic heart disease and

stroke (2.0 for both males and females) amongst diabetics from the Asia Pacific Cohort

Studies Collaboration (Woodward et al. 2003).

2I Endocrine and metabolic disorders

Haemolytic anaemia

We use Australian hospital data to estimate the incidence of hereditary haemolytic anaemia,

assuming that annual admissions at age 0 years represent incidence. We model beta

thalassaemia and ‘other’ haemolytic anaemia separately to account for different durations.

We assume that the average duration for beta thalassaemia is 35 years based on a USA

review (US Preventive Services Taskforce 1996) and we assume that the life expectancy of

persons with ‘other’ haemolytic anaemia is the same for sickle cell anaemia, that is, around

25 years lower than the population average. In the absence of specific weights we use the

GBD weight for very severe anaemia (0.25) and severe anaemia (0.09) for beta thalassaemia

and other haemolytic anaemias respectively.

Other non-deficiency anaemia

We model the disability associated with aplastic anaemia and autoimmune anaemia. We

base the prevalence of aplastic anaemia on Australian hospital data. We derive incidence and

duration in DisMod using prevalence data, Australian mortality data where aplastic anaemia

was an underlying condition and a remission of zero. We estimate the incidence of

autoimmune anaemia using hospital data and assume that the average duration is 3 months.

In the absence of a specific weight for other non-deficiency anaemias we use the GBD weight

for very severe anaemia (0.25).

Cystic fibrosis

Massie and colleagues (2000) found the incidence of cystic fibrosis in Victoria over a 9-year

period to be 3.5 per 10,000. This estimate is very similar to information from Queensland and

Western Australia (Bower et al. 2004; Queensland Health 2004). We apply the Victorian

estimate to the whole of Australia. We estimate the duration of cystic fibrosis in DisMod

using the above incidence, no remission, and an age- and sex- specific risk of mortality from

a patient-based USA study (Kulich et al. 2003). There is no disability weight for cystic fibrosis

available. As obstructive lung disease is a major sequela, and the disease is progressive and

fatal, we use the disability weight for severe chronic obstructive pulmonary disease (0.53).

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Haemophilia

We base our estimate of the incidence of moderate and severe haemophilia on Australian

data (Street & Ekert 1996). We do not model mild cases of haemophilia since we assume they

have zero disability, as bleeding only occurs as a result of injury. We use the same

assumptions about severity distribution, duration and disability weights as the previous

Australian burden study.

2J Mental disorders

The 1997 National Survey of Mental Health and Wellbeing, including the child mental health

and low prevalence disorder components, remains the only population-based data source for

our estimates of most mental disorders (ABS 1998a; Jablensky et al. 1999; Sawyer et al. 2000).

Table A1.3 summarises the mental disorders for which we calculated YLD, along with the

sources of data on which our incidence estimates are based.

Table A1.3: Sources of data for mental disorders

Data source Mental disorder

National Survey of Mental Health and Wellbeing 1997 Depression & anxiety; bipolar disorder; most substance abuse

(alcohol, sedative and cannabis drug dependence or abuse);

and borderline personality disorder

Low Prevalence (Psychotic) Disorders Study Psychotic disorders

Child and Adolescent Component of the National Survey of

Mental Health and Wellbeing 1997 (Sawyer et al. 2000)

Childhood disorders (separation anxiety disorder, attentiondeficit

hyperactivity disorder)

Epidemiological Study—National Drug and Alcohol Research

Centre Technical Report No. 198 (Degenhardt et al. 2004)

Heroin dependence

Alcohol and Other Drug Treatment Services National Minimum

Data Set (AODTS-NMDS) collection

<www.aihw.gov.au/drugs/datacubes/index.cfm> (accessed 15

December 2005)

Stimulant dependence

Reviews of epidemiological studies Eating disorders (anorexia nervosa and bulimia nervosa),

autism, and Asperger’s syndrome

Depression & anxiety, substance abuse (excluding heroin and

stimulant dependence), borderline personality disorder and bipolar

disorder

While the data sources have remained mostly the same as were used for the previous

Australian burden study, there are a number of key methodological changes. First, we have

grouped all anxiety disorders (panic, agoraphobia, social phobia, generalised anxiety

disorder, obsessive-compulsive disorder, post-traumatic stress disorder and separation

anxiety disorder) and the unipolar depressive disorders (major depression and dysthymia)

that were previously modelled separately into a single disease category. This is based on the

argument that the high degree of comorbidity and the similarity in psychological and drug

treatment means that all these disorders can be considered as part of the same entity, with a

continuum between mostly depressed to mostly anxious (for example (Andrews et al. 1990;

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Andrews & Slade 2002). The advantage of this approach is that it takes away some of the

difficulties of dealing with the frequent comorbidity among these disorders.

Second, disability weights for all conditions derived from the national mental health survey

continue to be based on the mental component score of the SF-12 but for this update we

calculate a per unit change in disability weight for each unit change in the mental component

score and apply this to all disorders. Dutch disability weights exist for mild, moderate and

severe depression as well as for six different anxiety disorders for a combined mild–

moderate state and a severe state. Assuming that mild, moderate and severe are 1, 2 and 3

standard deviations, respectively, below the population mean of the mental component score

we sought a mathematical function that best describes the range of disability weights. A

second-order polynomial function gave the best fit. This transformation of categorical

weights into a continuous scale allows us to calculate a disability weight for each respondent

in the survey. Any mental component score value greater than the population mean of 52 is

set to 0 and the weight for a mental component score of 20 is taken as the highest disability

weight even if the mental component score is lower (this is done because otherwise the

lowest mental component scores would correspond with a disability weight of greater

than 1).

Third, to deal with comorbidity, we apportion the disability weights calculated in the

National mental health survey equally between the comorbid mental health diagnoses for

each individual. In the previous Australian burden study we did the correction for

comorbidity at the level of the number of people affected and hence reported lower than

actual numbers of incident and prevalent cases.

Our general model for these conditions derives incidence figures from the National mental

health survey prevalence figures, using DisMod and assuming appropriate remission rates

and relative risks of mortality from a meta-analysis (Harris & Barraclough 1998). We use the

proportion of one-year prevalent cases reporting symptoms in the previous two weeks as an

approximation of the proportion of time with symptoms and thus assume that all these

conditions have a chronic nature with periods of remission in between.

For children aged 5–17 years, we use prevalence estimates for depression and anxiety from

the Child and Adolescent Component of the national mental health survey (Sawyer et al.

2000). In DisMod we use a remission rate of 0.043, a pooled estimate from follow-up studies

of people with various anxiety disorders (Steketee et al. 1999; Wewetzer et al. 2001; Yonkers

et al. 2003) and an increased relative risk of mortality of 1.5, a value in between the range of

meta-analysis estimates reported for anxiety and depressive disorders (Harris & Barraclough

1998).

The prevalence estimates for bipolar disorder in the previous Australian burden study were

based on the international literature. This was because the prevalence figures from the

National mental health survey were considered inaccurate due to a technical problem during

the conduct of the survey. Subsequently Mitchell and colleagues (2004) have re-analysed the

data and defined the prevalence of ‘euphoric hypomanic/manic syndrome’. They argue that

with this definition around 95% of cases of bipolar disorder are captured. For the current

estimates we use the same definition and adjust the 12-month prevalence by 100/95. In

DisMod we use a remission rate of 0.035 calculated from a follow-up study (Angst & Preisig

1995) and an increased relative risk of mortality of 1.96 in men and 1.76 in women (Harris &

Barraclough 1998).

In this study we include all personality disorders—rather than borderline personality

disorder only—but limit our estimates to those without any comorbid mental disorders. The

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proportion of comorbidity between personality disorders and other mental disorders is so

high that we argue that in most cases it ought to be seen as a risk factor rather than a

separate condition. However, in order to capture all disability from mental disorders we

include a category ‘isolated personality disorder’. The remission estimate of 17% is consistent

between two follow-up studies (Grilo et al. 2004; Zanarini et al. 2003). The relative risk of

mortality is 1.84 (Harris & Barraclough 1998).

In the previous Australian burden study, estimates for alcohol use disorder were made

separately for alcohol dependence and harmful alcohol use, and then presented as one

disease category. In the current update we combine the two categories and create one

DisMod model based on 12 month prevalence of any alcohol use disorder in the National

mental health survey. The two other parameters in DisMod are a remission rate of 23.7%

calculated from a two-year follow-up study (Booth et al. 2001), and an elevated mortality risk

of 1.8 in males and 3.84 in females (Harris & Barraclough 1998).

For cannabis dependence, we assume a remission of 8% (Swift et al. 2000) and no excess risk

of mortality. There are no follow-up studies of people with sedative dependence. We use the

same remission as in the cannabis model and apply an excess mortality risk of 2.1 reported

for ‘legal’ drug use (Harris & Barraclough 1998).

Heroin dependence and harmful use

Household surveys are likely to underestimate the true prevalence of heroin use (differential

response between users and non-users and a greater proportion of users not living in

households). Instead, we use higher estimates of regular heroin users based on triangulation

between five data sources: ABS opioid deaths, ambulance attendances for drug overdose in

New South Wales, New South Wales Health heroin pharmacotherapy client database, New

South Wales data on arrests for drug offences, and data from the Alcohol and Drug

Information Service on calls related to heroin use (Degenhardt et al. 2004). While the

detailed comparison of databases was done for New South Wales, extrapolations were made

for all jurisdictions by extrapolation of relationship between numbers under treatment or in

contact with police and opioid mortality figures from New South Wales and the opioid

deaths in each jurisdiction.

In the previous Australian burden study, we assumed very high remission after age 45 years

to reflect the low prevalence of heroin use. However, expert advice that this is a cohort effect

rather than a high remission effect explains the drop in prevalence at older ages. In current

estimates we ‘allow’ DisMod to build up prevalence figures at older ages.

Back projection methods by the National Drug and Alcohol Research Centre assumes a risk

of dying from overdose of 0.8% per year (Law et al. 2001). We assume a case-fatality rate of

1% to account for raised mortality from other causes. The overall relative risk calculated in

DisMod is of the same order of magnitude as reported elsewhere (AIHW: Ridolfo &

Stevenson 2001; Darke & Ross 2002). The disability weight for heroin dependence of 0.27 was

derived by Victorian mental health experts for the previous Australian burden study and is

close to the GBD disability weight estimate of 0.252.

Stimulant dependence

We decided to use treatment figures rather than the estimates of prevalence of stimulant

dependence from the National mental health survey as there has been a marked increase in

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the use of stimulants since 1997 and the survey results show an erratic age pattern as only

few cases were identified. Instead we estimate the prevalence of stimulant dependence from

the number of closed treatment episodes in 2002–2003 where the principal drug of concern

was listed as amphetamines (Alcohol and Other Drug Treatment Services National

Minimum Data Set) collection. We inflate these figures by 5.5 as described by McKetin and

colleagues (2005).

We estimate remission by first entering prevalence, a relative risk of 0 and a case-fatality rate

of 0, into DisMod. We thus get DisMod to produce an estimate of remission that best

replicates the age pattern of prevalence. The average remission across all ages was 12%. We

then run the DisMod model again with same prevalence, this remission rate and a relative

risk of 2.1 for excess mortality as reported for ‘legal drug use’ (Harris & Barraclough 1998).

We derive a disability weight for stimulant dependence as we have done for all other

conditions in the National mental health survey and thus assume that the same average

severity found among the lower number of cases with stimulant dependence in the survey

reflects that of all cases in the population.

Psychotic disorders

Estimates for psychotic disorders are based on prevalence from the Low Prevalence

(Psychotic) Disorders Study conducted in Australia in 1997 as part of the National Survey of

Mental Health and Wellbeing. This survey measured an overall estimate of 4.7 per 1,000

population. The low prevalence study suffered from a low response rate by general

practitioners contacted in the study areas and therefore under-represented people with

psychotic disorders who are solely managed by their general practitioner (Lewin & Carr

1998). Before conducting further analysis, we adjust upwards to one in three the number of

people in the survey who are wholly treated by a general practitioner and adjust downwards

by a factor of 0.841 to reflect only those with schizophrenia and related diagnoses and not

those with a diagnosis of bipolar or affective psychosis. Annual remission is based on a

number of longer term studies and is set at the median of the reported rates (1.5%) (Ciompi

1980; Harding et al. 1987; Harrison et al. 2001; Helgason 1990; Huber et al. 1980). We derive

incidence and duration figures from DisMod using a 54% higher risk of mortality overall for

people with schizophrenia (Harris & Barraclough 1998), with an age pattern imposed by the

relative frequency by age that schizophrenia is mentioned in death records. The DisMod

incidence output indicates that almost all psychotic disorders have their beginning in late

adolescence or early adulthood, with a small second peak in post-menopausal women. We

assume that the average time spent in psychosis is 30% (Leff et al 1992). We use a composite

weight based on 30% of the GBD weight for psychosis corresponding to the estimated time

spent in this state and 70% of the treated weight (0.3 x 0.627 + 0.7 x 0.351 = 0.434). The low

prevalence study reported a higher proportion (61%) of people with a psychotic disorder

having current delusions or hallucinations. It also stated that 86% are taking prescribed

medication and that 83% of the total reported that their psychotic symptoms respond to

pharmacological treatment. The first finding would indicate that our composite disability

weight is too low but the second finding would support a lower weight. For the Assessing

Cost-Effectiveness (ACE)–Mental Health study, disability weights for each individual in the

low prevalence study were estimated using a sliding scale between the highest and lowest of

Dutch disability weights for schizophrenia and anchoring individuals on this scale based on

their score on the diagnostic interview for psychosis disability module that was included in

the survey (Haby et al. 2004). The mean disability weight across the sample using this

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method is 0.39. We decided to continue to use the 0.434 disability weight as in the previous

Australian burden study.

Eating disorders

Estimates for bulimia are based on a prevalence rate of 0.7% among Swiss 14–17 year old

females (Steinhausen et al. 1997). This is the mid-point in the range of prevalence between

0.5% and 1% reported from more rigorous epidemiological studies (Gilchrist et al. 1998). We

calculate a remission rate of 0.21 from figures reported in a review of follow-up studies (Keel

et al. 1999). We derive incidence and duration estimates for women from these figures using

DisMod, assuming the age at onset is between 14 and 29 years with no increased risk of

mortality. Estimates for anorexia are based on a 0.5% prevalence among females older than

15 years (Gilchrist et al. 1998; Keel et al. 1999) and a remission rate of 0.11 calculated from a

follow-up study (Strober et al. 1997). We use DisMod to derive incidence and duration

estimates for women from these figures, assuming the age at onset is between 14 and 29

years with an increased annual risk of mortality of 0.59% (Sullivan 1995). We assume the

incidence in males is 10% of the rate in females. We use the Dutch weight of 0.28 for both

types of eating disorder.

Childhood disorders

Australian prevalence data for childhood attention deficit with hyperactivity disorder come

from the Child and Adolescent Component of the 1997 National Survey of Mental Health

and Wellbeing (Sawyer et al. 2000). We define attention deficit with hyperactivity disorder to

include children with a diagnosis on the survey and whose parents report the child having

more emotional or behavioural problems than have other children of the same age. The

estimates of burden of attention deficit with hyperactivity disorder were derived from

prevalence rates of 6% in male children, 3% in female children, 2% in male adolescents and

1% in female adolescents. Our incidence figures were derived from DisMod, assuming an

age at onset of 3–6 years and a remission rate of 0.15 (Hill & Schoener 1996). To reproduce

the prevalence pattern we use a higher remission rate of 0.25 in adolescents aged 10–19 years

and 0.3 thereafter. We assume no increased risk of mortality. We use the Dutch weights for

both mild and moderate-to-severe attention deficit with hyperactivity disorder (0.02 and

0.15), and weight these by the severity distribution found in the 1997 survey to derive a

composite disability weight.

Autism is part of pervasive developmental disorders; the other important condition in that

category is Asperger’s syndrome, which was described at about the same time as autism.

Autism is characterised by the triad of language or communication impairment, social

impairment and behavioural impairment (obsessions, rituals). However, Asperger’s

syndrome has only the latter two components and is not associated with intellectual

disability, as is the case with 80% of autistic children. Behavioural problems are a

predominant feature in children with Asperger’s syndrome.

We derive the incidence of autism and Asperger’s syndrome from an Australian study with

data from treatment and educational support services in Western Australia and New South

Wales. We assume no remission and an elevated risk of mortality as reported by Shavelle

and colleagues (2001). We use the average duration of mild intellectual disability and the

Dutch disability weight of 0.55 for autism, and for Asperger’s syndrome an estimated weight

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of 0.25 based on expert advice that the condition is worse than moderate to severe attention

deficit with hyperactivity disorder but much less severe than autism.

2K Nervous system and sense organ disorders

Dementia

A door-to-door population-based two-phase investigation method (screening followed by

detailed neurological examination by a psychiatrist) is the most accurate epidemiologic

approach to estimate the epidemiology of dementia and Parkinson’s disease (Benito-Leon et

al. 2004).

We base our estimates of the prevalence of dementia for people aged 65 years or over on a

recent European meta-analysis of population-based door-to-door studies conducted by the

Neurologic Diseases in the Elderly Research Group (Lobo et al. 2000). We proportionately

redistribute the one-third of cases that constitute ‘other or mixed type’ to Alzheimer’s and

vascular dementia. We estimate the prevalence of dementia below the age of 65 years from a

recent UK study of patients aged 30–64 years (Harvey et al. 2003).

We use relative risks of mortality for Alzheimer’s disease and vascular dementia from a

survival study of incident cases that controlled for comorbidity (Aguero-Torres et al. 1999).

The estimated mortality risk for all dementia from this is comparable to the results of the

meta-analyses of dementia prevalent cases and survival (Dewey & Saz 2001; Jagger et al.

2000). We prefer using the former because it provides type-specific survival data.

We derive incidence and duration using DisMod, based on the aforementioned

representative population-based studies of prevalence, assuming no remission and relative

risks from the incident-based survival study. This model gives average durations across all

ages for both sexes of around 4 years which was in keeping with the literature on the

survival of prevalent cases (Aguero-Torres et al. 1999; Helmer et al. 2001). We model

dementia as a progressive illness and discount the latter stages back to incidence of disease.

We use the disability weights derived by the previous Australian burden study (which

combined the Dutch weights with a severity distribution from a European population-based

cohort study).

Epilepsy

We base our incidence estimates for primary epilepsy on the 1980–84 Rochester

Epidemiology Project medical record linkage system (Zarrelli et al. 1999). We use these

incidence estimates, assuming no differentials by sex, with age-specific remissions (Annegers

et al. 1979) and an overall standardised mortality ratio of 1.3 (Tomson 2000) to derive

estimates of incidence and duration using DisMod. We use the Dutch disability weight for

epilepsy (0.110).

Parkinson’s disease

We only explicitly model primary Parkinson’s disease (ICD-10 code G20). We assume that

secondary Parkinsonism is accounted for under other relevant disease categories.

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We base our estimates of the prevalence of Parkinson’s disease from a recent European metaanalysis

of population-based door-to-door studies conducted by the Neurologic Diseases in

the Elderly Research Group (de Rijk et al. 2000). There are no sex differences in the

prevalence of Parkinson’s disease. We do not use the Australian studies on the prevalence of

Parkinson’s disease since we consider them to be outliers; they give prevalence estimates two

to three times higher than most of the literature (Chan et al. 2001, 2005).

We base our relative risk of mortality on the meta-analysis of prevalent cases of Parkinson’s

disease and survival undertaken by the Neurologic Diseases in the Elderly Research Group

(Berger et al. 2000). We plot and fit the risk of mortality by age using an exponential

trendline to smooth the irregular pattern by age.

We derive incidence and duration using DisMod assuming no remission and a relative risk

of mortality for males and females of 3.1 and 1.8 respectively, resulting in average durations

of 4.5 and 9.8 years. These durations are broadly consistent with durations reported in the

literature (Elbaz et al. 2003; Fall et al. 2003; Herlofson et al. 2004; Hughes et al. 2004;

Morgante et al. 2000).

We derive disability weights from an Australian patient-based cohort study (Hely et al. 1999)

reporting on the distribution of Hoehn and Yahr stages (which corresponds with the

descriptions of the severity states of Parkinson’s disease for which Dutch disability weights

are available) and survival at each 2-year interval. We model Parkinson’s disease assuming

that all cases start with mild symptoms and progress over time to moderate and then severe

symptoms over time. From simple linear regression lines we derive an annual increase in

those with moderate and severe symptoms. The proportion of cases over time who are in the

moderate category is the balance between those moving from mild to moderate and those

exiting moderate by shifting to the severe category. For each age group we calculate the

average disability weight during the estimated average duration. As severity progresses with

time since incidence and younger age groups have longer durations, disability weights are

highest in the younger age groups.

Motor neurone disease

We base our incidence estimates for motor neurone disease on Australian mortality data. We

assume that incident cases equal annual deaths due to motor neurone disease. Our estimates

for males and females are consistent with international literature for males (Chancellor et al.

1993). We assume average durations of 2.9 years for those aged 0–64 years and 1.9 years for

people aged 65 years or over. We base our duration assumptions on Australian and

international literature (Forbes et al. 2004; Sach 1995). In the absence of a specific disability

weight we use the Dutch weight for progressive multiple sclerosis (0.67).

Multiple sclerosis

We estimate the prevalence of multiple sclerosis using 1981 and 1996 estimates of multiple

sclerosis for some Australian states and territories (Barnett et al. 2003; Simmons et al. 2001)

with extrapolations based on latitudinal differences for jurisdictions with no estimates. We

assume that changes over time represent improvements in identification rather than changes

in epidemiology. We derive incidence and duration using DisMod assuming no remission

and age and sex specific case-fatality rates based on a 25-year New Zealand cohort study

(Miller et al. 1992).

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In 10.8% of patients the disease has a progressive course from the onset (Roxburgh et al.

2005). The median time it takes to reach an Expanded Disability Status Scale score of 6

(equivalent to having to use a cane) in those with a relapsing-remitting course is 30 years

(Tremlett et al. 2006). We use the Dutch weights for relapsing-remitting (0.33) and

progressive (0.67) phases and assume that those with relapsing-remitting disease have 30

years at the lower disability weight and the remainder at the higher disability weight level.

Huntington’s chorea

Huntington’s chorea is modelled in DisMod using prevalence from the literature (McCusker

et al. 2000), assuming no remission and mortality data. We assume a duration of 20 years for

the younger age groups and apply the durations from DisMod for ages 65 years or over.

Assuming similar progression of disease as in Parkinson’s, we adopt the weights for the

three stages of this disease.

Muscular dystrophy

For muscular dystrophy in males, we use the average incidence rates from New South

Wales, Victoria, Queensland, Western Australia and the Australian Capital Territory (Cowan

et al. 1980; Emery 1991). The incidence for females is calculated by applying the sex ratio

from mortality data. In the absence of specific weights for this condition, we assume the

initial symptomatic phase is similar to the initial stage of Parkinson’s disease, the phase in

which walking becomes impossible is similar to that of paraplegia, and the final stage is

equivalent to quadriplegia.

Vision loss

Our incidence estimates for vision loss are based on the results of the Melbourne Visual

Impairment Project, which assessed visual acuity and the prevalence by cause of mild,

moderate and severe visual impairment in a sample representative of Victorians (Weih et al.

2000). For glaucoma, refraction errors, macular degeneration and the category ‘other vision

loss’, we derive incidence and duration of related visual impairment using DisMod,

assuming no remission and a relative mortality risk of 1. For glaucoma we use Dutch

disability weights for mild, moderate and severe vision loss to derive a composite disability

weight from the severity pattern across all ages (as the age-specific data are based on small

numbers). For macular degeneration, refraction errors and ‘other vision loss’ we derive agespecific

disability weights.

We estimate the incidence of mild and moderate cataract-related vision impairment using

Australian hospital data assuming that 50% of surgically corrected cases had vision loss in

both eyes prior to operation for 1 year on average and that 90% of cases are mild and 10% are

moderate. We estimate the prevalence of un-operated cataracts as the difference between the

prevalence of cataract-related visual impairment estimated by the Melbourne study and the

number of surgical corrections. This leads to a small estimate of un-operated cataracts in the

elderly over 80 years of age. We use this to estimate the incidence of un-operated cases of

cataract-related severe vision loss in DisMod, assuming no remission and a relative risk of

1.5. For cataract-related vision loss at ages 0–14 years we assume duration of 2 years and for

ages 15 years or over we assume a 1-year duration. Incident cases of un-operated cataract

were assumed to be prevalent cases waiting on average 1 year for cataract surgery. We use

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Dutch disability weights for mild and moderate cataract-related vision loss. For severe

cataract-related vision loss we estimate a combined disability weight using the Dutch

weights for each of the stages along with prevalence data from the Melbourne study to

derive combined stages age-specific disability weights. The proportion of glaucoma and

cataract-related vision loss attributable to diabetes is then determined from relative risks

from the Blue Mountain Eye Study (Mitchell et al. 1997) and only non-diabetes-related vision

loss is included in the YLD estimates for these categories.

Hearing loss

We model hearing loss as a progressive condition with mild (25–34 dB and 35–44 dB),

moderate and severe stages so that prevalent cases with moderate or severe impairment are

regarded as incident cases of mild impairment at an earlier age. We use survey prevalence

data from South Australia (Wilson et al. 1999), initially modelling the prevalence of severe

hearing loss, no remission and a relative risk of 1 in DisMod. We use incidence of severe

hearing loss from the DisMod output as ‘mortality’ in the moderate hearing loss DisMod

model; this takes the cases of severe hearing loss out of the pool of susceptible cases for

moderate hearing loss and hence gives more accurate average durations than if remission

were used as remitted cases in the DisMod model, as the cases continue to be subject to the

hazard of incidence. Similarly, we use incidence of moderate hearing loss as ‘mortality’ in

mild hearing loss (35–44 dB) and incidence of mild hearing loss (35–44 dB) as ‘mortality’ in

mild hearing loss (25–34 dB). From examination of the prevalence data by level of severity

and age, and assuming that all cases progress from the mildest to most severe category, it

seems reasonable to assume that on average progression to the next severity level occurs at 5

year intervals between mild (25–34 dB) and mild (35–44 dB), and at 10 year intervals from

mild (35–44 dB) to moderate and moderate to severe. From the cross-sectional data on

prevalence it is not possible to estimate these progression times exactly. However, to be

consistent with other disease models where subsequent severity levels for the same health

state are discounted back to first incidence, we apply a 25-year lag for severe hearing loss, 15

years for moderate and 5 years for the mild (35–44 dB) categories. Dutch weights of 0.04, 0.12

and 0.37 apply for mild (35–44 dB), moderate and severe hearing loss, respectively. For the

mild (25–34 dB) category we assume a disability weight of 0.02, half that of the mild

(35–44dB) category.

Intellectual disability

Intellectual disability is categorised into the following levels: mild, moderate, severe and

profound, with intelligence quotient (IQ) ranges of 50–69, 35–49, 20–34, <20 respectively.

This categorisation is based on the Dutch disability weight criteria.

We estimate the incidence of mild-moderate and severe intellectual disability using the

Intellectual Disability Exploring Answers Database, a Western Australian population-based

dataset of children with intellectual disability identified through disability and educational

services between 1983–1996. We adjust the severity distribution of incidence data to account

for unspecified cases and redistribute cases so that the severity level as defined by IQ is

comparable to the Dutch disability weight criteria. Then we extrapolate incident cases by the

two severity levels (mild-moderate and severe) to four levels of severity (mild, moderate,

severe and profound) using the average severity distribution from two Australian studies

(Einfeld & Tonge 1996; Wellesley et al. 1992). We assume that because neither study

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recruited cases from school services, mild cases were underestimated and base our

estimation of mild cases on the balance of the mild-moderate category. This gives the

following proportionate distribution of incident cases by severity: mild (76%), moderate

(14%), severe (7%) and profound (3%).

In order to derive plausible durations of intellectual disability by the four stages of severity

we calculate the proportional difference in life expectancy by level of severity of intellectual

disability in comparison to the life expectancy of the general population from a 35-year

Finnish follow-up study (Patja et al. 2000).

We model the incidence and duration of intellectual disability in DisMod assuming that 90%

of intellectual disability, based on Australian population data, occurs in the first year of life

and the remaining 10% occurs in the 1–4 age group, no remission, and a relative risk of

mortality that gives an average duration by severity level based on the extrapolation of

Finnish data to the 2003 Australian life table.

We do not include the YLD for intellectual disability as a discrete category in the main

listings of this burden study. Instead, incident cases of intellectual disability are attributed to

underlying causes (such as congenital disorders, epilepsy, autism, perinatal conditions,

meningitis, brain tumours and cerebral palsy) using findings from the Australian Child to

Adult Development Study, a longitudinal study of behavioural and emotional problems in

429 young people with intellectual disabilities. We use data from two publications of this

study to produce the proportionate distribution of the underlying cause of intellectual

disability by severity level and sex (Mowat et al. unpublished; Partington et al. 2000). We

calculate YLD for each underlying cause using incidence and duration derived from DisMod

and the Dutch disability weights for mild, moderate, severe, and profound intellectual

disability.

Migraine

We base our prevalence estimates for migraine on the National Health Survey data and our

incidence estimates for migraine on international data (Stewart et al. 1991). We estimate the

incidence and duration of migraine in DisMod using prevalence, incidence, and a casefatality

rate of zero. Within DisMod, we use manual smoothing to extrapolate incidence to

older ages. We assume that 20% of cases receive treatment in developed countries. We

assume that the average duration for untreated and treated episodes is 24 hours and 6 hours

respectively. We derive average disability weights for untreated and treated models using

frequency, severity, and disability weight data from Global burden of migraine in the year 2000

(Leonardi & Mathers 2003).

2L Cardiovascular disease

Ischaemic heart disease

Three health states are modelled separately for ischaemic heart disease: angina pectoris,

acute myocardial infarction and heart failure. We model the incidence of angina pectoris as

the number of admissions to hospital without any mention of angina in any previous

admission in 15 years of linked hospital records in Western Australia (Department of Health

of Western Australia et al. 2005; Holman et al. 1999) and adjust by the ratio of admissions for

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angina pectoris between Western Australia and the whole country. We model angina

pectoris pre- and post-myocardial infarct together. The duration is determined in DisMod,

assuming remission estimated from the number of revascularisation procedures from

Australian hospital data and age- and sex-specific case-fatality rates calculated over the

period 1998–2003 in ‘prevalent cases’ of angina pectoris (that is, anyone with an admission

for angina pectoris since 1988 and still alive over the follow-up period).

Assuming that about half of the declining ischaemic heart disease mortality reflects change

in the case-fatality rate rather than incidence (Unal et al. 2004), we apply half of the ischaemic

heart disease mortality trend observed over the period 1979–2003 in DisMod to incidence

and the other half to case-fatality.

We assume 95% of angina is experienced at the mild-moderate level with the corresponding

Dutch disability weight of 0.08, and the remaining 5% with a weight of 0.57.

For people discharged alive following acute myocardial infarction in 2003, we calculate a

period of 3 months of disability at the GBD treated disability weight of 0.395.

Heart diseases resulting in heart failure

Population-level prevalence or incidence information on heart failure is absent in Australia

and scarce elsewhere. In 2001, by extrapolation from US studies a rough estimate was made

of about 300,000 prevalent cases of heart failure in Australia (Krum 2001). Complicating

factors in the estimation of heart failure prevalence are that estimates from other countries

and different time periods may not apply to the current Australian situation. Ischaemic heart

disease is the underlying cause of heart failure in the majority of cases, and there has been a

steady decline in the risk of ischaemic heart disease since the early 1970s combined with

improved survival due to improvements in therapeutic options. The first would cause a

reduction in prevalence, while the latter would lead to higher prevalence. It is not clear what

the net effect of these two influences would be on the prevalence of heart failure.

Using hospital data is also not straightforward as the current wisdom is that there has been a

change in the case load of people presenting to tertiary health facilities with this condition,

following the wider use of improved pharmacological treatment combinations since the

1990s, resulting in a greater proportion of cases being successfully treated in primary care.

Nevertheless, our model for heart failure starts with a description of the epidemiology of

hospitalised heart failure, for which we have extensive information from Western Australia.

From the linked data set of all hospitalisations and deaths in this state, we identify people

who presented to hospital with heart failure (either as a primary diagnosis or as an

associated condition) at any time in the period 1990–2003. To derive case-fatality, we

calculate the number of years lived between 1998 and 2003 by anyone who had ever been

admitted with a diagnosis of heart failure since 1990. The case-fatality rate was then taken as

the number of deaths over person-years of follow-up in 5-year age groups after subtracting

out the background mortality.

The complete descriptive epidemiology in this group is derived in DisMod from incidence

and case-fatality, the third parameter being zero remission (that is, people do not recover

from heart failure). We include in this model a declining trend in case-fatality over the last

10 years of 3% per year for males and 1% per year for females (derived from our survival

model), and a 2% decline in incidence per year for both males and females over the last

35 years. This latter figure is half the annual decline we observe for ischaemic heart disease

mortality over this period, ischaemic heart disease being the major driver of heart failure

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risk. The other half of the decline in ischaemic heart disease mortality we assume to be due to

improvements in case-fatality (see above) (Unal et al. 2004).

There is little information on the incidence of heart failure in the community (that is, not yet

diagnosed cases and those diagnosed but treated in the primary case setting without

requiring hospitalisation). We assume that this group has less severe disease with better

survival compared to their hospitalised counterparts. We also assume that when they die, it

is less likely that heart failure will be mentioned as the underlying cause of death. We have

data on the number of hospitalised cases of heart failure who died with heart failure as the

underlying cause of death and we know the overall number of deaths coded to heart failure.

Assuming that the linkage of hospital and death records in Western Australia is complete,

we then assume that the balance of heart failure coded deaths occur in never-hospitalised

cases of heart failure. In the absence of data to characterise the never-hospitalised cases of

heart failure we make two assumptions. First, to account for lower severity we assume that

their case-fatality rate is lower by 25%. Second, we assume that deaths in non-hospitalised

heart failure cases are 25% less likely to be coded to heart failure.

Among hospitalised cases that die, the probability of receiving an underlying cause of death

code of heart failure (428 in ICD-9 and I58 in ICD-10) is 3.6% in males and 5.3% in females. If

non-hospitalised cases are 25% less likely to be assigned a code of heart failure the

percentage of total excess deaths coded to heart failure would be 2.7% in males and 3.9% in

females. From this we can derive the total number of deaths due to heart failure in nonhospitalised

cases (3,199 in males and 3,958 in females over the period 2001–2003). By adding

in the 3,833 deaths from ever-hospitalised cases of heart failure in males and 4,186 in females,

we can calculate the average population mortality rate of heart failure over the period. These

rates (calculated by age and sex) are the inputs to a second iteration of DisMod, together

with zero remission and the case-fatality rate of the first DisMod model of hospitalised heart

failure cases adjusted downwards to reflect the proportion of never-hospitalised cases

having 25% lower case-fatality. We continue to use the same assumptions on trends in casefatality

and incidence as in the first model. The output of the second DisMod iteration then

gives us the incidence, prevalence and average durations for all heart failure, which feed into

our YLD calculations. The total prevalence of heart failure in Australia in 2003 is thus

estimated to be 220,000 cases.

We then identify the underlying causes for all heart failure cases—rheumatic heart disease,

hypertensive heart disease, ischaemic heart disease, pulmonary heart disease, inflammatory

heart disease, non-rheumatic valvular heart disease—in the Victorian linked hospital

admission dataset between 1996 and 2002, if any of these were mentioned as a cause in the

six years of hospital admission data. We then adjust the proportions, by age and sex, of all

underlying causes so they add up to 100% to account for cases with none or more than one

underlying cause identified. We use the duration, together with the incidence and

prevalence estimates initially obtained from the heart failure model described above,

multiplied by the proportion of heart failure cases for each of the above six underlying

causes, to calculate the YLD for each of these conditions (including ischaemic heart disease).

Stroke

We model stroke in terms of the following health states: a short period of disability for those

who die in the first 28 days, survival beyond 28 days with no permanent impairment at one

year after onset, and survival beyond 28 days with permanent impairment. Admissions for

stroke in the year 2003 are the starting point for our estimate of incidence. To get an

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approximation of first-ever stroke incidence we take the ratio of hospital admission figures

from the North-East Melbourne Stroke Incidence Study (NEMESIS) area during the time of

the study to the reported NEMESIS first-ever incidence figures (Thrift et al. 2000) and apply

this ratio to 2003 Australian hospital admissions for stroke. Next, we subtract a proportion of

cases that die, using a 28-day case-fatality rate by stroke subtype as reported by Thrift and

colleagues.

The case-fatality rate of stroke comes from the Western Australian linked database using a

similar approach to that described above for heart failure. The case-fatality rate for DisMod

is the excess mortality in prevalent cases, defined in our analyses as anyone still alive at the

beginning of the follow-up period (mid 1998–mid 2004) with a mention of stroke during any

admission between 1989 and 1998 as well as any new cases of admitted stroke during followup.

Follow-up time and numbers of deaths were analysed for each 5-year age group and the

overall case-fatality rate reduced by the relevant background mortality.

Analyses by Judy Katzenellenbogen in Western Australia for her PhD indicate that after the

first 28 days the case-fatality rate does not vary significantly by type of stroke and that the

DisMod assumption of a case-fatality hazard that varies with age but not with time since

stroke is plausible.

Disability weights are derived from one-year follow-up data of stroke survivors in the Perth

Community Stroke Study analysed by Judy Katzenellenbogen to compare health status

information before and at 4 months and 1 year after the stroke event.

Other cardiovascular disease

Heart failure is the main disability from rheumatic heart disease, non-rheumatic valvular

disease, hypertensive heart disease and the group of inflammatory heart diseases (including

myocarditis, cardiomyopathy, endocarditis and pericarditis). The proportions of heart failure

cases for each of these causes are derived as described above for all heart failure. For

rheumatic heart disease and non-rheumatic heart disease we do a separate DisMod model

based on heart failure prevalence for these causes and taking into account the remission

through surgical interventions using Australian hospital data.

For aortic aneurysm, we assume the hospitalisation rate reflects incidence. For peripheral

vascular disease, we assume the hospitalisation rate reflects prevalence at all ages. We derive

the incidence from DisMod, assuming a relative risk of 2 and a remission rate of 0.1, which

approximates the number of surgical interventions as a proportion of total prevalent cases.

For aortic aneurysm, we assume a one-month period of disability during treatment and no

residual disability for those who survive treatment. Without a disability weight for this

health state, we use the derived weight for laparotomy (0.349). For peripheral vascular

disease, we use derived weights of 0.243 and 0.257 for men and women respectively, based

on severity distributions from the 1993 Australian disability survey. Weights for amputations

are from the GBD study.

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2M Chronic respiratory diseases

Chronic obstructive pulmonary disease

We estimate the prevalence of chronic obstructive pulmonary disease for cases with a forced

expiratory volume in one second of less than 70% of predicted (excluding those with a doctor

defined diagnosis of asthma) using the 1994–95 Busselton Study (Knuiman et al. 1999). While

this study sample comprises a selected rural population in Western Australia, we assume the

data are representative of prevalence in all areas of Australia. We use DisMod to estimate the

incidence of chronic obstructive pulmonary disease in 1994, assuming no remission and a

relative risk equivalent to that calculated from death rates attributed to smoking (see section

on risk factors). We include a trend of –2% per year for males and 3% per year for females

based on trends in chronic obstructive pulmonary disease mortality since 1979. We calculate

2003 incidence estimates by applying age- and sex-specific trends (based on mortality) to the

1994 incidence estimates. We then use DisMod with the same assumptions about remission

and relative risk of mortality to model prevalence, age of onset and duration for 2003. We

derive a composite average disability weight for males (0.168) and females (0.159) using the

Dutch weights for mild, moderate and severe chronic obstructive pulmonary disease and the

proportionate distribution by level of severity of dyspnoea from the Busselton Study. We

add the proportion of heart failure cases attributed to ‘pulmonary heart disease’ on the basis

that chronic lung disease is the underlying cause.

Asthma

We estimate the prevalence of asthma for cases that have a positive airway hyperresponsiveness

test and wheezing in the last 12 months from the literature (Bauman et al.

1992a; Peat et al. 1992, 1994, 1995; Toelle et al. 2004). Although these two criteria may

underestimate the ‘true’ prevalence of asthma, a reliance on self-reported wheeze alone

overestimates figures by up to a third (Toelle et al. 1992; Van Asperen 1995). We estimate the

prevalence of asthma in children aged 1–2 years to be 5.75%, using a report of ‘wheeze’ from

the US (Martinez et al. 1995) which we adjust by 42% to obtain an estimate that reflects those

with wheeze having asthma (Peat et al. 1994, 1995; Toelle et al. 2004). We estimate the

prevalence of asthma to be 12.3% in boys and 8.8% in girls aged 3–18 years, using an average

of 3 studies from 1992 to 2002 (Peat et al. 1994, 1995; Toelle et al. 2004) and a male-to-female

ratio of 1.4:1 (Gergen et al. 1988). For adults, we average the prevalence data from the early

1990 studies (Bauman et al. 1992a; Peat et al. 1992, 1994, 1995) since these were the last

studies in adults to have used a positive airway hyper-responsiveness test and assume no

change in the prevalence of asthma over time based on the literature and the observed trend

in children. We use a male-to-female ratio of 1:1.5 (DHS 2002) to give an estimated 2003

asthma prevalence of 5% and 7.5% in male and female adults. We derive incidence estimates

from DisMod assuming age-specific remission rates from a follow-up study in the US

(Bronnimann & Burrows 1986), which are consistent with overall remissions reported by

Australia studies (Xuan et al. 2002). From findings reported by Bauman and colleagues, we

calculate that asthmatics are symptomatic 12% of the time (Bauman et al. 1992b). Rather than

use the Dutch weight for this health state (0.36), which we consider to be for a more severe

health state than the average for symptomatic asthmatics in the population, we use a derived

weight of 0.229 based on the severity distributions found in the 1998 Australian disability

survey (ABS 1998b) and the disability weight regression model. The remainder of the time

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we assume is spent in a state equivalent to the Dutch weight for asthma controlled by

treatment (0.03). This results in a combined weight of 0.054.

2N Diseases of the digestive system

Peptic ulcer disease

In the absence of Australian population data on the frequency of peptic ulcer disease, we

assume that all incident cases of peptic ulcer disease visit a general practitioner and base our

estimates on the Australian general practitioner data. We assume that 83% of cases are

treated by Helicobacter pylori eradication therapy, which has a cure rate of 90% (Mollison et al.

1999). We model those who are cured using eradication therapy as being symptomatic for

one month, with no residual disability. We assume that the remainder of those who are

treated but not cured (including those receiving alternative treatments) receive relief from

their treatment but remain with the condition for the GBD duration. Untreated cases we

assume to be symptomatic for the same period. Because the annualised Dutch weight for

peptic ulcer disease is implausible, we use derived weights from the Dutch study for both

symptomatic and treated states.

Cirrhosis of the liver

The methods of deriving estimates of alcohol-related cirrhosis and the category of ‘other’

cirrhosis have been described in the section on hepatitis.

Inflammatory bowel disease

We model two manifestations of inflammatory bowel disease: Crohn’s disease and ulcerative

colitis. We estimate the incidence of inflammatory bowel disease in adults from a European

study (Shivananda et al. 1996) and for children we pool estimates from a number of

international studies based on a recent review (Griffiths 2004). The relative risks of mortality

due to the two types of inflammatory bowel disease were based on the findings of a recent

large UK study which showed that inflammatory bowel disease was associated with a small

overall increase in mortality after controlling for smoking and sex (Card et al. 2003). We

assume no remission and derive a composite disability weight (0.224), assuming that 20% of

time is spent with active exacerbation and the remainder is in ‘remission’ (Griffiths 1995;

Hendriksen et al. 1985; Stonnington et al. 1987).

For inflammatory bowel disease (and vascular insufficiency of the intestine, diverticulitis

and intestinal obstruction), we assume that a proportion of cases have more complicated

surgery involving the creation of a stoma (a surgical opening in the skin of the abdomen for

excretion of faeces) that can be either permanent or temporary. We estimate the incidence of

inflammatory bowel disease cases that receive a temporary or permanent stoma from

Australian hospital data. We apply the ratio of stoma for Crohn’s disease to stoma for

ulcerative colitis from an analysis of Victorian linked hospital data. Similarly the average

duration of temporary stoma was estimated from Victorian hospital data from 1998–99 to

2001–02 to determine if they were closed and, if closed, the time to closure. The duration of

permanent stoma was taken to be the same as the duration of the respective condition. We

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assume stomas not yet closed within this period remain open indefinitely. In the absence of a

specific weight for this condition, we derive a weight (0.204) from the disability weight

regression model.

Other diseases of the digestive system

We base the incidence estimates for appendicitis, intestinal obstruction, diverticulitis, gall

bladder and bile duct disease, pancreatitis and vascular insufficiency of the intestine on the

numbers of people with a relevant hospital procedure or diagnosis from Australian hospital

data. With the exception of appendicitis, these conditions were not considered in either the

GBD or Dutch studies. We adopt a 2-week duration for appendicitis, and a 3-week duration

for gall bladder and bile duct disease, intestinal obstruction, vascular insufficiency and

pancreatitis. For each of these conditions, we assume the GBD weight for appendicitis. For

gall bladder and bile duct disease, we use cholecystectomies or bile duct incisions but ignore

people admitted with un-operated cholelithiasis on the assumption that these people are

largely asymptomatic.

2O Genitourinary diseases

Nephritis & nephrosis

We base the incidence of dialysis and transplant patients on the Australian dialysis and

transplant data from which we derive durations for both categories of patients using

DisMod. For dialysis patients, we use case-fatality rates to match observed deaths and

remission through transplant, and apply the Dutch weight for diabetic nephropathy (0.290).

In the first 6 months after transplant, we assume a health state equivalent to the Dutch

weight for diabetic nephropathy (0.290). For the remaining period with the transplant, we

use a weight of 0.11, which is equivalent to both the GBD weight for treated renal failure and

the Dutch weight for ‘uncertain prognosis’. We derive untreated end stage renal failure from

the difference between dialysis or transplant deaths and total renal deaths, to which we

apply an average duration of 1 year prior to death at the GBD weight for untreated renal

failure (0.104). We use Australian dialysis and transplant data on underlying renal disease

distribution to attribute YLD from diabetic nephropathy to diabetes, analgesic nephropathy

to the injury category of medical misadventure, and congenital dysplasia and polycystic

kidney disease to congenital urogenital disease, and retain only those for primary renal

disease in the ‘nephritis & nephrosis’ category.

Benign prostatic hypertrophy

We base the incidence of benign prostatic hypertrophy on Australian hospital data. Based on

expert advice we adjust the number of benign prostatic hypertrophy cases upwards to

account for the proportion of cases that receive medical instead of surgical treatment. We

also assume, based on expert opinion, that half of all benign prostatic hypertrophy cases

receive surgical treatment, a proportion of whom experience complications or continuing

symptoms following surgery (1% with lifelong incontinence at a derived weight of 0.204,

15% with lifelong impotence at the GBD weight of 0.195, and 5% with urethral stricture for

4 weeks at the GBD weight of 0.151). Of those opting for medical treatment, we assume 70%

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use alpha-blocker drugs, of which half are cured. The other half may then try surgery. We

assume none of those receiving drugs other than alpha-blockers are cured. We apply the

GBD weight for symptomatic benign prostatic hypertrophy to each of these intervention

pathways assuming the following durations: 1.5 years for surgery, 1 year for successful

medical treatment, 2 years for unsuccessful medical treatment then surgery, and lifelong for

unsuccessful medical treatment but no surgery.

Urinary incontinence

We derive incidence rates of incontinence from DisMod using prevalence figures reported in

a review of Australian and international literature (AIHW: Lea 1993) and from Women’s

Health Australia. We assume that a number of diseases and injuries are associated with this

condition, most of which are more prevalent at older ages, and that the underlying causes

are multi-factorial and interrelated. Based on a multivariate analysis (Chiarelli et al. 1999),

we assume that, while all disability from incontinence among younger men and younger and

middle-aged women belongs under this category, half that experienced by middle-aged and

older men and older women is already captured under other conditions either explicitly (for

example, as a sequela for benign prostatic hypertrophy among men) or implicitly as part of

the overall weightings for these conditions (for example, severe stroke). For unaccounted

incontinence, we apply an average of the GBD weight for moderate incontinence and the

derived weight for benign prostatic hypertrophy-related severe incontinence using severity

distributions from the 1998 Australian disability survey.

Infertility

We estimate the prevalence of infertility from a 1988 population survey of infertility, surgical

sterility and associated reproductive disability in Perth, Western Australia (Webb & Holman

1992). This survey indicates that of the 3.5% of couples with non-surgical infertility, 68%

have an associated reproductive disability defined in terms of the couple being unable to

achieve a desired level of reproductive function. From a review of patients at an Adelaide

infertility clinic indicating that 83% of couples with reproductive disability seek assisted

reproductive technologies, 30% of whom achieve a pregnancy within 2 years (Weiss et al.

1992), we derive a net prevalence of 1.02% and 0.73% for short-term reproductive disability

and 0.67% and 0.48% for long-term reproductive disability in females and males respectively.

The causes of infertility are derived from recent national data on assisted conception and

reproduction (AIHW: Dean & Sullivan 2003; AIHW: Ford et al. 2003). For short-term cases,

we assume incident cases equal prevalent cases divided by the duration, which we assume is

2 years. For long-term cases, we derive incidence and durations from DisMod assuming nonzero

remission rates from ages 45 years or over to account for declining prevalence of

reproductive disability reflecting adoptions and changes in reproductive goals. For women,

we subtract from the total number of long-term incident cases the estimated incidence of

infertility as a sequela to maternal sepsis, abortion and pelvic inflammatory disease, the

disability of which is calculated under chlamydia and gonorrhoea. We determine the

duration of long-term infertility by subtracting the age at onset estimated in DisMod from

45 years. GBD weights are used for both short- and long-term reproductive disability.

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Other genitourinary diseases

For this residual category, we assume the application of a simple YLD to YLL ratio of one

across the age groups is sufficient to capture the morbidity from other genitourinary diseases

in men. This method, however, does not capture the significant burden experienced by

women, particularly at younger ages. We therefore calculate separate models for menstrual

disorders and hysterectomies for menorrhagia, genital prolapse and endometriosis.

We base our estimates for menstrual disorders on women who report they often have severe

period pain or premenstrual tension in the last 12 months from Women’s health Australia.

For severe period pain we assume a duration of 1 day per month and a disability weight

similar to that for caesarean section. For menstrual tension we assume a duration of 2 days

each month and we use the disability weight for mild depression. We use DisMod to model

the conditions, assuming no excess mortality and remission of 0.1 for ages less than 50 years.

We model disability from hysterectomies associated with menorrhagia, genital prolapse and

endometriosis in terms of disability from both the procedure and the resulting infertility. We

derive the number of procedures from hospital data and we assume a 2-week duration at the

derived weight for laparotomy of 0.349 (compare with estimates for caesarean section).

Following the findings of a survey of surgical sterility in Perth (Webb & Holman 1992), we

assume the majority of women who undergo a hysterectomy have completed their

reproductive objectives, and that infertility leads to disability in 3.3% of cases with

endometriosis. We apply the GBD weight for infertility.

2P Skin diseases

Eczema, acne and psoriasis

We model the incidence of severe eczema (that is, an episode in the past 12 months that

disrupts sleep on average one or more nights per week) using self-reported prevalence data

from a study of Melbourne school children (Robertson et al. 2004) and from the National

Health Survey for adults (ABS 2001c). For other skin conditions we limit our estimates to

severe acne and moderate and severe psoriasis. Prevalence figures for acne are based on a

study of Australian school children and a study of adults in Central Victoria (Kilkenny et al.

1998; Marks et al. 1999). Prevalence figures for psoriasis were derived from the National

Health Survey and from the central Victorian study (Marks et al. 1999; Plunkett et al. 1999).

We derive incidence and duration estimates from DisMod assuming no excess mortality and

a remission rate of 0.1 for eczema (Thestrup-Pedersen 2003), 0.27 for acne (assuming 70%

spontaneous remission after 4 to 5 years) and 0.3 for psoriasis. For eczema we derive a

disability weight (0.019) from the disability weight regression model which we adjust for

3 symptomatic episodes per year lasting 6 weeks in total. For acne we use the unadjusted

disability weight for eczema from the disability weight regression model (0.056) and for

psoriasis we apply the GBD weight for vitiligo.

Other skin diseases

We model the disability associated with chronic leg, skin and varicose ulcers, excluding

decubitus and cellulitis which we assume are captured elsewhere. We use the weighted

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incident cases of skin ulcers from Australian general practitioner data to estimate the

incidence of other chronic skin ulcers. YLD for diabetic foot is included within the diabetes

mellitus model. To avoid double-counting diabetic foot we adjust our incident estimates for

skin ulcers using Western Australian aetiological data on the proportion of leg ulceration

cases that had diabetes (Baker et al. 1992). In the absence of more specific information we use

the same assumptions for duration (8.9 months) and disability (0.131) as the diabetic foot

model.

2Q Musculoskeletal diseases

Musculoskeletal diseases are highly prevalent in the population. The fair to good test–retest

reliability of self-reported musculoskeletal diseases and the consistent correlation with pain

make health survey self-reports of some use to measure musculoskeletal conditions.

Although the prevalence of most musculoskeletal diseases differs substantially depending

on the measurement method, with self-report showing the highest prevalence, the pattern of

prevalence in men and women is often similar. A higher prevalence of herniated disc of the

back and gout is found in men, whereas for most other musculoskeletal diseases the

prevalence is higher among women than among men (Picavet & Hazes 2003).

Rheumatoid arthritis

Given the small numbers in Australian studies on rheumatoid arthritis and problems with

proper incidence and remission measurement, we base our incidence estimates for this

condition on the international literature. For juvenile chronic arthritis, we use findings from

a population study during 1984–1988 in Sweden (Gare & Fasth 1992). For adults, we use

results from a 40-year follow-up study of a population-based cohort in Rochester, Minnesota,

USA (Doran et al. 2002). We derived durations from DisMod assuming a relative risk of

mortality of 1.6 at ages 15 years or over (Pincus et al. 1994), with no increased risk for

children, and a remission rate of 0.04 (Prevoo et al. 1996) indicating that, while drug

treatment may slow the disease process and remission is the ultimate endpoint of treatment,

most therapeutic options have fallen short of achieving this (Sesin & Bingham 2005). Because

progression through the three stages of rheumatoid arthritis described by the Dutch weights

is relatively rapid, we do not model this condition as progressive. Rather we apply an

average of the Dutch weights using severity distributions for American adults (Hakala et al.

1994) and those relating to Swedish children (Gare & Fasth 1992).

Osteoarthritis

While there are a few Australian population-based studies on self-reported osteoarthritis

(Jones et al. 1995; March et al. 1998), we prefer to base our estimates for this condition on

reported findings of radiographic osteoarthritis (grade 2 and above) by affected joint, age

and sex from a large-scale study in Massachusetts, USA (Jones et al. 1995; March et al. 1998).

We model hip and knee osteoarthritis only, given the high correlation between osteoarthritis

of the hip, hand and fingers (Spector et al. 1997). We used DisMod to derive average

durations, assuming a slightly increased risk of mortality (1.1) and the observed remission

rate from joint replacement surgery. Because osteoarthritis is a relatively slow progressive

disease, with few patients showing symptomatic progression over an 11-year period (Ahern

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& Smith 1997), we apply an average of the relevant Dutch weights, assuming a severity

distribution based on the Framingham study (Guccione et al. 1990).

Back pain

Back pain is a very common condition, with about 70–90% of people suffering from it in

some form at some point in their lives (Hicks et al. 2002). Back pain may be viewed as

running either an acute or chronic course. Acute back pain is usually considered to have a

short duration and tends to resolve within days to weeks. However, recurrence of acute

episodes is common and there is some contention as to the difference between recurring

acute back pain and long-term chronic back pain. A duration of back pain lasting at least 3

months commonly underlies the definition of chronic back pain (NINDS 2006), and is often

likely to continue indefinitely (Von Korff & Saunders 1996). Our estimates for back pain are

based on self-reported prevalence of recent episodes, and long-term back pain from the 2003

Australian disability survey and the 1995 National health survey. We model recent episodes

of (acute) back pain and long-term (chronic) back pain separately. Prevalence of long-term

back pain resulting in at least mild disability is obtained from the Australian disability

survey. Of these, the cases that were due to recent episodes of back pain were not identified

separately. We therefore estimated the proportion due to recent episodes by applying the

percentage of recent cases of long-term back pain from the 1995 National Health Survey. We

use the Dutch weight for low back pain (0.06) as the disability weight for recent episodes of

back pain, which applies to an average health state involving some problems in walking

about and in usual activities, as well as moderate pain or discomfort. We assume an average

duration of 4 days for painful and limiting episodes of back pain. To model chronic back

pain, we use the prevalence of long-term back pain (not identified as recent episodes as

described above) from the 2003 Australian disability survey. We use DisMod to derive the

incidence and duration of chronic back pain, assuming a remission rate of 10% and no

increased risk of mortality. For many people, there are few treatment alternatives and

complete relief is rare (Atkinson 2004). We assume that 14% of long-term cases experience

constant or persistent pain (Quittan 2002), and 86% experience pain 1 day per week. We use

the GBD disability weight for chronic intervertebral disc pain of 0.103.

Slipped disc

Our estimates for slipped disc are based on numbers of intervertebral disc procedures from

Australian hospital data. We assume only 7.5% of incident cases of disc displacement receive

surgery (Deyo et al. 1990), and derive total annual episodes from this proportion. We assume

on average an episode of discomfort lasts 4 weeks. For those who receive surgery, we take

the median time of 224 days from onset of symptoms to recovery reported in the literature

(Rasmussen 1996). In the absence of weights for both these health states, we use the Dutch

weight for low back pain (0.06). Based on a 5-year follow-up study (Kurth et al. 1996), we

model 14% of operated cases as going on to experience long-term chronic pain with a

lifelong duration at the GBD disability weight for chronic intervertebral disc of 0.103.

Occupational overuse syndrome

Occupational overuse syndrome (formerly known as repetition strain injury) is a contentious

condition with considerable disagreement within the literature about its aetiology and

174

pathophysiology (Byrne 1992; Cohen et al. 1992; Helme et al. 1992). Our model uses selfreport

prevalence data on ‘repetition strain injury’ from the 2003 Australian disability survey

from which we derive incidence figures using DisMod assuming an average duration of

3 years and no mortality. In the absence of Dutch or GBD weights for this condition, we use

sex-specific derived weights to account for the fact that all males in the 1993 Australian

disability survey had mild or no handicap, whereas 26% of females had moderate handicap

and 17% had severe or profound handicap.

Gout

Our estimates for gout are based on self-reported prevalence from the National Health

Survey which has the same overall result as found in a general practitioner study in the UK

(Mikuls et al. 2005). We assume a slight increased risk of mortality associated with gout

(relative risk=1.1) and no remission, based on information that at 1 year 62%, at 2 years 78%

and at 10 years 93% has had at least one repeat attack (Alamo Family Foot and Ankle Care

2005). Fitting a Weibull function to these figures gives an average time to the next episode of

2.2 years, but this is rather high because of the skewness of the function. The median time to

next episode is 0.44 years. We assume that 10% has chronic symptoms and the remaining

90% has an attack of 1 week every 0.44 years. Given that people may suffer gout at varying

levels, from acute attacks of a short duration to chronic gout, we assume on average one

attack per 2 months lasting 1 week in 90% of people and the remaining 10% suffer chronic

ongoing disease at the GBD disability weight of 0.061.

Other musculoskeletal disorders

Because mortality for musculoskeletal conditions is low and because 49% of deaths from

musculoskeletal disorders do not fall within the above categories, a derivation of disability

for this rest category by applying a ratio of YLD to YLL for the explicitly modelled

musculoskeletal conditions is not plausible. Therefore we try to model disability from all

other conditions explicitly. In the absence of detailed information, we define an ‘other’

category comprising both prevalent minor conditions and more serious diseases (for

example joint derangement and disorders; osteopathies; chondropathies and other bone

disorders; connective tissue diseases; and soft tissue problems such as rheumatism,

ganglions, bunions, bursitis, cramps, tenosynovitis and tennis elbow). We base our estimates

for these conditions on the prevalence of other musculoskeletal disorders that have not been

accounted for in each of the musculoskeletal models described above from the 2001 National

Health Survey. Based on figures from the 2003 Australian disability survey, we assume a

proportion of prevalent cases report on refer to musculoskeletal sequelae of other diseases or

injuries, which we account for by adjusting overall prevalence figures downwards by 50%.

For recent non-chronic cases, we assume the same duration and weight as for recent episodes

of back pain. For chronic cases, we derive incidence rates and durations from DisMod

assuming no excess mortality and a remission rate of 0.1. We take the proportion reporting

symptoms in the 2 weeks before interview as an approximation of the proportion of time

spent symptomatic and assume symptomatic chronic cases experience a health state

equivalent to the weight for low back pain.

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2R Congenital anomalies

Congenital heart disease

We model the disability associated with four types of congenital heart disease for live-born

infants: surgically treated atrial or ventricular septal defect, surgically treated Fallot’s

tetralogy or transposition of great vessels, surgically treated pulmonary stenosis, and

complex but not curatively operable congenital heart disease. We derive the incidence of the

first three conditions from Australian hospital data by assuming that all curative procedures

represent an incident case with disability. We assume a duration of 1 year before operation

with disability equivalent to the Dutch weight for moderate heart failure (0.35) and postsurgery

we use relevant Dutch weights and assume reduced life expectancy, except for those

with septal defects (Miyamura et al. 1993; Nollert et al. 1997a, 1997b). We assume disability

starts at birth and we discount YLD back to birth to account for this. We derive the incidence

of other congenital heart malformations from Victorian birth defects data. Following expert

advice, we assume that 50% of these cases are complex but not curatively operable. We

assume that duration is half of those with surgically treatable conditions and use the relevant

Dutch weight (0.72).

Digestive system malformations

We model the disability for anorectal and oesophageal atresia and other digestive system

malformations. We estimate the incidence of digestive system atresia for cases surviving

28 days using Victorian birth defects data. We assume 26 weeks of disability from birth at the

GBD weight for anorectal atresia (0.85). After this period, we assume that a proportion of

both types of atresia cases have lifelong problems (15% and 20% respectively) and decreased

life expectancy (by 10 and 5 years respectively) and disability equivalent to health state

111211 for two-thirds of the time (0.037) (Ludman & Spitz 2003). We estimate the incidence

of other digestive system malformations using data from the Australian congenital

malformations dataset (AIHW: Hurst et al. 2001). We assume no long-term disability, and a

1-month period of disability from birth equivalent to the GBD weight for anorectal atresia.

Renal agenesis

We estimate the incidence of unilateral and bilateral renal agenesis for cases surviving

28 days using Victorian birth defects data. For unilateral cases we assume that 20% of

survivors have ongoing problems, with a life expectancy of 70 years and a disability of 0.067.

For bilateral cases we assume an average duration of 3.5 days and use the GBD weight for

renal agenesis (0.85). We also calculate YLD for renal failure due to renal dysplasia based on

attributions from Australian dialysis and transplant data.

Other urogenital tract malformations

We model the disability associated with the following urogenital tract malformations: cystic

kidney disease, obstructive defects of renal pelvis and ureter, and other urinary tract

malformations. We estimate the incidence of cases of other urogenital tract malformations

surviving beyond 28 days from the Victorian, Western Australian and Australian birth

176

defects data. We assume 30% of cases have chronic lifelong problems, with a life expectancy

of 50 years and a disability weight of 0.067. YLD were also calculated for end-stage renal

failure due to cystic kidney disease.

Other congenital anomalies

We estimate the incidence of anencephaly using Australian mortality data for newborns,

assuming deaths are equivalent to incident cases. We assume a duration of 1 week with a

disability weight of 1. For spina bifida, we estimate the average annual number of live births

that survive the first 28 days from Victorian birth defect data (Riley & Halliday 2004). We

derive an average disability weight (0.52) based on the Dutch weights for each level of

severity combined with severity distributions from expert advice. We estimate the incidence

of surgically treated cleft lip and cleft palate from Australian hospital data, assuming that all

curative procedures represent a case and that all cases are treated within the first year. We

assume disability equivalent to the ‘treated’ GBD weights (0.016, 0.015 respectively). YLD

estimates for Down syndrome and ‘other chromosomal anomalies’ are calculated as

described in the section on intellectual disability (see Section 2K).

We estimate the incidence of abdominal wall defects (exomphalos and gastroschisis) in

infants surviving >28 days using 2001 Australian birth defects data (AIHW NPSU 2004) and

survival data from the Victorian birth defects data. We assume a duration of 4 weeks based

on Australian and international literature (Dimitriou et al. 2000; Sharp et al. 2000) and apply

the GBD weight for abdominal wall defect. Based on expert advice we assume that 20% of

cases have lifelong problems, a shortened life expectancy by 20 years, and disability weight

of 0.200 (the Dutch weight for young adult in permanent stage after surgical repair to Fallot’s

tetralogy).

2S Oral conditions

Caries

The incidence of caries is measured by one or more new dental cavities (caries increment).

The occurrence of dental caries in an individual is measured using the DMFT or DMFS

index: the number of decayed (D), missing (M) and filled (F) primary or permanent teeth (T)

or surfaces (S). A review of the relationship between DMFT and DMFS suggests that DMFS

data should be adjusted by a factor of 1/3.5 to be consistent with DMFT data (Carvalho et al.

2004; Hopcraft & Morgan 2005; Rosen et al. 2004).

For children and adults we estimate the incidence from representative Australian caries

prevalence data: the 2000 Child Dental Health Survey (AIHW: Armfield et al. 2004) and the

1987–88 National Oral Health Survey of Australia (Barnard 1993). Fitting linear regression

lines to the prevalence data gives slopes in children (1–14 years) of 0.25 (AIHW: Armfield et

al. 2004; Davies et al. 1997) and in adults (15–59 years) of 0.27 (Barnard 1993). For older

adults (60 years or over) and nursing home residents (60 years or over) we estimate the

incidence of caries from the South Australia Dental Longitudinal Study (AIHW DSRU 2002)

and the 1998 Adelaide Dental Study of Nursing Homes (AIHW: Chalmers et al. 2001),

respectively. Based on the 5-year increment of all new carious surfaces, the 1-year increment

(assuming that the incidence of carious surfaces over the 5-year period was evenly

177

distributed) is 0.98 (AIHW DSRU 2002). The 1-year increment of new carious surfaces in

nursing home residents is 3.5 (AIHW: Chalmers et al. 2001). We use our DMFT/DMFS

adjustment factor to give annual caries increments of 0.28 and 1.0 respectively for older

adults in the general population and nursing homes.

The previous Australian burden study assumed a symptomatic duration of 10 weeks based

on advice from the Australian Research Centre for Population Oral Health. More recent

work, based on patient self-report, by this group suggests durations in the order of 81 weeks

(Brennan & Spencer 2004, 2005). However, both of these estimates refer to time spent with

and without symptoms. A review of the literature shows that there is a paucity of

information on symptomatic caries, specifically mean duration of symptoms and proportion

of people who are symptomatic. A patient-based study in children in the UK reported that

78% of the children sampled presented within 1 month of pain onset (Mason et al. 1997)

whereas a patient-based study in New Zealand observed that 67% of adults presented within

1 month of pain onset (Whyman et al. 1996). Patient-based samples are biased as they do not

reflect all cases of caries in the community. Neither of these studies provided data on the

mean durations for those people experiencing symptoms for greater than 1 month. We

estimate the average time symptomatic for those people presenting with caries problems by

fitting a lognormal distribution to the midpoint of the observed durations. This gives mean

durations of symptomatic caries of 28 days in children and 55 days in adults. We base our

estimate of people with symptomatic caries (32.4%) on the findings of the 1998 Australian

Longitudinal Study of Dentists’ Practice Activity (Brennan & Spencer 2002).

Following the first Australian burden of disease study the Australian Research Centre for

Population Oral Health developed disability weights for oral disease using a patient-based

sample in South Australia (Brennan & Spencer 2004, 2005). Disability weights for caries

(0.044), periodontal disease (0.023) and denture problems (0.026) in this study were higher

than comparable Dutch weights used in the previous Australian burden study (0.005 for

caries involving a filling and 0.014 for caries involving an extraction, 0.007 for periodontal

disease, and 0.004 for edentulism). We did not use these Australian-derived disability

weights because patient-based samples are likely to under-represent asymptomatic people,

and questions with limited response categories are likely to bias results. For instance, the

duration-related question was ‘During the period that you have had this dental problem,

what percentage of the time (0% = none of the time, 50% = half of the time, 100% = all of the

time) have you experienced the limitations listed above in relation to: mobility, self-care,

usual activities, pain/discomfort, anxiety/depression, cognition?’ (Brennan & Spencer 2004,

2005). Both of these limitations are likely to over-estimate the percentage of people reporting

problems for each of the health dimensions as well as the duration of their symptoms.

We follow expert advice and derive a disability weight for symptomatic caries (0.057) using

the disability weight regression model (health states: 20%—111211 and 80%—111111).

Edentulism

We estimate the prevalence of edentulism (loss of all natural teeth) for the general

population and nursing home residents using the 2002 National Dental Telephone Interview

Survey (AIHW: Carter & Stewart 2003) and the 1998 Adelaide Dental Study of Nursing

Homes (AIHW: Chalmers et al. 2001), respectively. We derive incidence and duration using

DisMod, based on these studies, assuming no remission and no excess case-fatality. We

model a 2% declining time trend to reflect the observed decline of the prevalence of

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edentulism from 20.5% in 1979 to 8.0% in 2002 (Sanders et al. 2004). We use the same

disability weight as in the previous Australian burden study.

Periodontal disease

We estimate the prevalence of periodontal pockets larger than 6 mm using data from the

1987–88 National Oral Health Survey of Australia (Barnard 1993). Expert advice suggested

that periodontal disease is a largely asymptomatic risk factor for tooth loss; pain occurs in

around 1% of time when an abscess forms in a periodontal pocket; and the typical duration

of periodontal disease is around 15 years. We derive incidence and duration using DisMod

based on the Australian prevalence data, remission rates that reflect 15 years average

duration and no case-fatality. A new disability weight for periodontal abscess was estimated

(0.056) based on the disability weight regression model (health state 111211).

Pulpitis

We estimate the incidence of pulpitis using the proportion of patients sampled in the 1998

Longitudinal Study of Dentists’ Practice Activity (AIHW: Spencer & Brennan 2002) who had

a main diagnosis of pulpal infection and the total number of dental consultations in Australia

in 2003. We assume that most people with pulpal infection will visit a dentist. We estimate

the total number of dental consultations by multiplying the proportion of people who visited

a dentist in the last 12 months by the mean number of dental visits per person (from the 2002

National Dental Telephone Information Survey (AIHW: Carter & Stewart 2003)) and 2003

population data (excluding the edentulous population). Expert consultation suggests that a

symptomatic duration of 1 month is plausible for pulpitis with the first few weeks consisting

of intermittent pain and the last week being of more severe and consistent pain. We assume

that 71.3% of people with pulpitis presenting in pain, a figure which we derive from the 1998

Longitudinal Study of Dentists’ Practice Activity. We use the disability weight regression

model to estimate a disability weight for pulpitis assuming that 1 week is spent in moderate

pain and 3 weeks are spent at a level of the disability for moderate pain for 10% of the time.

2Z Chronic fatigue syndrome

We base our model for chronic fatigue syndrome on the internationally accepted US Centers

for Disease Control and Prevention criteria, which state that for a patient to receive a

diagnosis of chronic fatigue syndrome, they must have severe chronic fatigue of 6 months or

longer duration with other known medical conditions excluded by clinical diagnosis, and

concurrently have four or more of the following symptoms: substantial impairment in shortterm

memory or concentration; sore throat; tender lymph nodes; muscle pain; multi-joint

pain without swelling or redness; headaches of a new type, pattern or severity; unrefreshing

sleep; and post-exertional malaise lasting more than 24 hours. The symptoms must have

persisted or recurred during six or more consecutive months of illness and must not have

predated the fatigue (Fukuda et al. 1994).

Following expert consultation we conceptualise two manifestations of chronic fatigue

syndrome: (a) post-infective fatigue syndrome which constitutes between 30–40% of cases

and is characterised as an acute outcome of viral and non-viral infections, has a disability

starting point of moderate severity, a median duration of 12 months, and around 99%

179

recovery at 2 years (Hickie et al. submitted 2005; Wilson et al. 2001); and (b) protracted

chronic fatigue syndrome, which constitutes the remaining 60–70% of chronic fatigue

syndrome cases, where cases have an insidious onset with initially severe disability followed

by cases fluctuating around 50–80% of their previous healthy state, and a median duration of

around 7 years. We assume that the disability associated with post-infective fatigue

syndrome is included within the disability weights and durations in the relevant infectious

disease models (explicitly in the arbovirus estimates but not for other viral infections such as

Q fever and Epstein-Barr virus which are subsumed in the rest of infectious disease

category).

We base our estimates of prevalence for protracted chronic fatigue syndrome on the

population-based study of chronic fatigue syndrome conducted in Wichita, Kansas, USA in

1997 (Reyes et al. 2003). In the previous Australian burden study we used prevalence

estimates based on an Australian prevalence study of chronic fatigue syndrome (Lloyd et al.

1990). This study’s applicability in the current context is limited due to the different

diagnostic criteria used and the physician referral sample. The population-based study by

Reyes and colleagues (2003) showed that only 16% of people identified with chronic fatigue

syndrome had previously been diagnosed as such by a medical practitioner. Although it is

not clear how similar the epidemiology of chronic fatigue syndrome is between the US and

Australia, the findings from an international multi-centre study of the prevalence of chronic

fatigue syndrome in patients lend support to the notion that the epidemiology of chronic

fatigue syndrome is similar in the two countries (Wilson et al. 2001).

We model incidence and duration using DisMod, assuming no excess mortality and

remission rates which gave an average duration of 7.3 years (Reyes et al. 2003). We assume

that 90% of the time people with chronic fatigue syndrome are symptomatic, using findings

from the 1993 Australian disability survey. In the absence of an established disability weight

for chronic fatigue syndrome we use the disability weight estimated for the previous

Australian burden study.

3 Injuries

We model the disability from non-fatal injuries where a person has an injury severe enough

to warrant emergency department or inpatient hospital treatment but that does not lead to

death. This method assumes that injuries treated outside the hospital system do not result in

significant disability. We derive non-fatal incident injuries from Australian hospital data. We

classify incident cases according to a matrix of 14 ‘external cause of injury’ categories (12

unintentional and two intentional) and 32 ‘nature of injury’ categories (for example fractures,

burns, wounds, brain injury, spinal cord injury). We exclude admissions for the same ICD-10

code within 90 days, on the assumption that these are re-admissions, as well as, those

resulting in death. Given that it is not uncommon for multiple sites of the body to be

damaged from a single accident, we estimate disability for only the most disabling ICD-10

code associated with each incident, on the assumption that the disability for the other ICD-10

codes is captured in the weight for the more severe injury. We redistribute ill defined injuries

and adjust estimates for ‘amputated finger’ as in the previous Australian burden of disease

study. We use disability weights, durations and the risk of mortality as per the GBD study.

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Appendix 2: Methods for attributing risk

In this section we describe our methods for assessing the contribution of 14 health risks to

the total burden of disease and injury in Australia. For most risks, our analyses are based on

methods developed by the WHO CRA project and described in detail elsewhere (Ezzati et al.

2004a). Briefly, the main inputs are the prevalence of exposure to a health risk in a

population and information on the risk of disease, injury or death (referred to here as relative

risk or hazard) from this exposure, which is typically derive from systematic reviews of the

international literature. Our analyses are not comprehensive since choices had to be made

about which risks to include on the basis of certain criteria, as outlined at the beginning of

Chapter 4. We begin by describing the methodological basis of our analyses, the population

attributable fraction.

Estimating population attributable fractions

The population attributable fraction (PAF) is a subtype of a more general measure—the

‘potential impact fraction’ (PIF). The PIF measures the proportional reduction in disease or

injury burden experienced by a population that would occur if the population were

subjected to an alternative or ‘counterfactual’ distribution of exposure to a particular health

risk. If the alternative exposure scenario is set to a level such that it represents the lowest

possible risk in a population (no exposure, for example), the PIF represents the total amount

of burden that is attributable to that risk; in this instance it is called the ‘population

attributable fraction’ (Eide & Heuch 2001; Miettinen 1974). For health risks that are measured

on a continuous scale, the PIF can be defined thus:

0 0

0

( ) ( ) ( ) ( )

( ) ( )

m m

x x

m

x

RR x P x dx RR x P x dx

PIF

RR x P x dx

= =

=

− ′

=

􀂳 􀂳

􀂳

Where RR(x) = relative risk at exposure level, P(x) = population distribution of exposure,

P’(x) = counterfactual distribution of exposure, and m = maximum exposure level

(Equation 1)

When a risk is measured on a categorical scale, the discrete version of the PIF formula is

(Eide & Heuch 2001; Walter 1980):

􀂦

􀂦 􀂦

=

c

c c

c

c c

c

c c

P RR

P RR P RR

PIF

*

Where c = an index for category, P = prevalence, and P* = prevalence after a change, and

RR = relative risk

(Equation 2)

181

The difference between Equation 1 and Equation 2 in practical terms is that the latter can

easily be resolved in a spreadsheet environment, whereas the former requires more

advanced mathematical techniques. Equation 2 is mathematically the same as the PAF

formula for risk factors with multiple categories given by English and colleagues (Equation

3), if the counterfactual is set as the hypothetical minimum distribution (English et al. 1995).

( 1) 1

( 1)

− +

= 􀂦

􀂦

c

c c

c

c c

P RR

P RR

PAF

(Equation 3)

Choice of theoretical minimum

Calculating a PAF requires the explicit characterisation of an exposure distribution that

represents the lowest possible level of risk in a population. This has been termed the

‘theoretical minimum exposure distribution’ and corresponds to zero exposure for some

risks (for example smoking). For other risks, however, zero exposure is inappropriate

because it is physiologically impossible (for example systolic blood pressure, BMI and

cholesterol). In this case the lowest levels observed in specific populations and

epidemiological studies described in the literature are used instead. For example, a

theoretical minima of 115 mmHg for systolic blood pressure and 3.8 mmol/L for total

cholesterol (each with a small standard deviation) are the lowest levels at which the doseresponse

relationships have been characterised (Chen et al. 1991; Eastern Stroke and

Coronary Heart Disease Collaborative Research Group 1998; Law et al. 1994). For factors

with protective effects (fruit and vegetable consumption and physical activity), the

theoretical minimum exposure distribution is based on information from high exposure

populations about the level to which the benefits continue to accrue given current scientific

evidence.

Estimating attributable burden

Age- and sex-specific PAFs are calculated for each health risk and heath outcome pair using

the relationships in Equations 1 and 2. Where a relative risk of disease or injury is different to

the relative risk for death, two PAFs are calculated, one for non-fatal burden and the other

for fatal burden. PAFs are then multiplied with the relevant burden estimates for that health

outcome and the sum of the burden across all outcomes affected by a health risk constitutes

the total attributable burden for that risk. For example, if there are 1,000 deaths from

ischaemic heart disease and 500 from stroke in a particular age and sex category, and the

PAFs for cholesterol leading to ischaemic heart disease and stroke are 0.5 and 0.3

respectively, the mortality attributable to high cholesterol equals 1,000 Χ 0.5 + 500 Χ 0.3 = 650.

In other words, if the population had been exposed to the hypothetical minimum cholesterol

distribution instead of the current distribution, 650 fewer deaths would have occurred.

Table A2.3 summarises the exposure levels, theoretical minima, health outcomes and sources

of relative risks for each of the 14 health risks analysed in this report. Table A2.4 summarises

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our estimates of exposure in the Australian population to each of these risks. A brief

description the specific methods we used for each risk is provided below.

Tobacco

Given the long lag time between exposure to tobacco smoke and the occurrence of cancers

and COPD, the attributable burden cannot be estimated from the current prevalence of

smoking. Even with good historical information on smoking prevalence, it is not

straightforward to determine the current amount of illness that is due to smoking because

the lag time between the relevant exposure and disease is variable. Therefore, we used the

method of Peto and colleagues, who proposed an artificial compound prevalence measure of

the relevant past exposure to tobacco (Peto et al. 1992). This ‘smoking impact ratio’ is derived

from a comparison of lung cancer mortality rates in the population of interest and lung

cancer mortality rates among non-smokers and smokers observed in a large long-term

follow-up study in the United States. We used this smoking impact ratio instead of the

current prevalence in the standard calculation of attributable fractions for the other cancers

and COPD. Compared with cancers and COPD, the mean time between exposure to tobacco

and all other adverse health outcomes is considerably shorter. We therefore used prevalence

estimates of smoking for adults aged 18 years and over in 2001, two years before our baseline

year of 2003 (ABS 2001c).

Our previous calculations of attributable mortality burden included only those diseases for

which English and colleagues report strong evidence of an association (English et al. 1995).

For this report, we added other conditions for which reasonable evidence of an association

with tobacco exists (AIHW: Ridolfo & Stevenson 2001): cancer of the stomach, endometrial

cancer, peripheral vascular disease, pneumonia, inflammatory bowel disease, injuries from

fires and Parkinson’s disease. Tobacco has a small protective effect against Parkinson’s

disease and endometrial cancer. We omitted peptic ulcer disease, given evidence of its

largely infectious aetiology. We also added the burden attributable to smoking from macular

degeneration (Mitchell et al. 1999; Tomany et al. 2004).

In addition, we calculated the burden from passive smoking using attributable fractions for

lung cancer, ischaemic heart disease, and asthma in children (NHMRC 1997a). For lower

respiratory tract infection, sudden infant death syndrome and otitis media in children due to

passive smoking, we used the prevalence of maternal smoking (Turrell et al. 2002) and

relative risks from the US Surgeon General’s Report (US Department of Health and Human

Services 2006) and NHMRC (NHMRC 1997a). We also estimated the burden of low birth

weight due to smoking during pregnancy using the relative risk from Ridolfo and Stevenson

(2001) and estimates of smoking during pregnancy from Laws and Sullivan (2005).

High blood pressure

We used the AusDiab study (Dunstan et al. 2002) to estimate distributions of high blood

pressure by age and sex in the Australian population. Despite a low response rate AusDiab is

the only recent and representative study that has measured this risk in Australia. Relative

risks came from Lawes and colleagues (2004a). We used the CRA theoretical minimum

distribution for blood pressure (mean 115, SD 6 mmHg) as the counterfactual in this analysis.

183

High body mass

We used the AusDiab study (Dunstan et al. 2002) to estimate distributions of body mass

index (BMI) by age and sex in the Australian population. Relative risk of type 2 diabetes

came from the Asia Pacific Cohort Collabortation (2006); the relative risk of all remaining

conditions associated with high body mass came from James and colleagues (2004). We used

the CRA theoretical minimum distribution for BMI (mean 21, SD 1 kg/m2) as the

counterfactual in this analysis.

Physical inactivity

Recent developments have led to the treatment of physical inactivity as a four-level

categorical variable by subdividing the exposure group labelled as ‘sufficiently active’ in the

CRA project into those ‘meeting current recommendations’ and ‘highly active’. While

physical activity levels equivalent to 2.5 hours per week of moderate-intensity activity

(approximately 4000kJ/week) are considered an important target for population health

benefits, the protective effects are expected to continue to higher levels. Therefore, the

theoretical minimum exposure distribution was chosen to be the whole population in the

‘high active’ category to increase consistency with the counterfactual exposure distribution

of other risk factors (Bull 2003; Murray et al. 2003; Powles & Day 2002) (Table A2.1). The

required prevalence data were derived from the NHS 2001 (ABS 2001c). The exercise related

questions in this survey relate to physical exercise undertaken for recreation, sport, health or

fitness purposes, conceptually excluding physical activity undertaken as a part of work or

for other purposes. This may underestimate the amount of physical activity undertaken, and

therefore our analyses may overestimate the burden of disease attributable to physical

inactivity.

The associated hazards were modified to correspond to the new referent category of ‘highly

active’. Given no available quantitative meta-analysis with comparable categories, risk

estimates were derived from a synthesis of recent reviews (Kelley & Goodpaster 2001;

Kesaniemi et al. 2001; Kohl 2001; Oguma et al. 2002; Thune & Furberg 2001; Williams 2001)

and findings from several recent studies in which the results were reported separately by

intensity of activity as well as total volume of activity (Manson et al. 2002; Sesso et al. 2000).

The relative risk of ischaemic heart disease for the inactive group compared to ‘high active’

was set at 2.0, based on reviews of studies with both physical activity and fitness measures as

well as a recent study’s differential results for moderate versus vigorous activity. The likely

linear dose-response relationship (Kesaniemi et al. 2001) was represented by the arithmetic

midpoints for those classified as ‘meeting current recommendations’ and ‘insufficiently

active’. For stroke, the mean of nine studies summarised in the systematic review and metaanalysis

by Blair and colleagues (2001) was used (relative risk of 2.0). The findings from the

review by Thune and Furberg (2001) were used to derive the risk estimate for colon and

breast cancer. There has been no quantitative review of diabetes and physical activity;

therefore the relative risks from the CRA project were adjusted by the same magnitude as for

ischaemic heart disease. It is recognised that these estimates of risk are derived from a

synthesis of the available scientific evidence and alternative interpretations are possible.

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Table A2.1 Physical activity exposure categories

Physical activity level Definition

High 3 sessions x at least average 40 minutes vigorous AND total of at least 1500 METmins/week(a)

Recommended

3 sessions x at least average 20 minutes vigorous OR 5 x 30 minutes moderate OR 600

METmins/week

Insufficient Some activity but not meeting recommendation

Inactive No activity

(a) The standard metabolic equivalent, or MET, level. This unit is used to estimate the amount of oxygen used by the body during physical

activity. One MET = the energy (oxygen) used by the body sitting quietly, perhaps while talking on the phone or reading a book.

The harder the body works during the activity, the higher the MET.

High blood cholesterol

We used the AusDiab study (Dunstan et al. 2002) to estimate distributions of high blood

cholesterol by age and sex in the Australian population. Relative risks came from Lawes and

colleagues (2004b). We used the CRA theoretical minimum distribution for serum cholesterol

(mean 3.8, SD 0.5 mmol/L) as the counterfactual in this analysis.

Alcohol

There are a number of recent data sources on the prevalence of alcohol consumption in the

Australian population, including the 2004 National Drug Strategy Household Survey

(NDSHS 2004) (AIHW & DoHA 2005) and the 2001 National Health Survey (NHS 2001) (ABS

2001c). The NHS 2001 focuses on the quantity of alcohol consumption on the three most

recent days on which alcohol was consumed in the week prior to interview, while the

NDSHS 2004 explicitly quantifies the amount of alcohol drunk on the day prior to interview.

Of these, only the NHS 2001 collected information on the type and brand of alcoholic drinks

consumed as well as the number. Also, the NHS 2001 gives average daily alcohol

consumption over the previous week in millilitres. For this reason, we used the NHS 2001 to

estimate the prevalence of alcohol consumption for adults aged 18 years or over.

We categorised the prevalence of alcohol consumption into the four levels used in English

and colleagues’ analysis of the risks of alcohol consumption (English et al. 1995), and with

the NHMRC’s recommendations on alcohol consumption (NHMRC 1992) (Table A2.2). The

prevalence of each level of alcohol intake was estimated by age and sex from the average

weekly consumption of alcohol after conversion to standard drinks per day. Data for people

interviewed on each day of the week were reweighted to obtain prevalence of alcohol

consumption based on equal samples for each day of the week. Those that last drank alcohol

more than 1 week ago were classified as abstainers.

185

Table A2.2 Classification and prevalence of alcohol intake levels used in this report

Average number of standard drinks (= 10 g alcohol) per day

Alcohol intake Male Female

Abstinence 0–0.25 0–0.25

Low 0.26–4.00 0.26–2.00

Hazardous 4.01–6.00 2.01–4.00

Harmful >6 >4

Source: English et al. 1995

We used relative risks and population attributable fractions from Ridolfo and Stevenson

(AIHW: Ridolfo & Stevenson 2001) for conditions for which there is evidence of causation by

alcohol consumption. English and colleagues (1995) estimated that 44% of fire injuries are

attributable to alcohol; this was not updated by Ridolfo and Stevenson (AIHW: Ridolfo &

Stevenson 2001). We revised these estimates with the addition of more recent studies, and

produced a separate PAF for fire injuries and scalds or other burns for both YLD and YLL.

We also updated the drowning PAF of 0.34 from Ridolfo and Stevenson (AIHW: Ridolfo &

Stevenson 2001) with age-specific estimates from Driscoll and colleagues (AIHW: Driscoll et

al. 2004) who found that 17% of unintentional drownings were attributed to alcohol (blood

alcohol content of at least 0.10 g/100 ml). English and colleagues (1995) derived a PAF of 0.07

for alcohol, and occupational and machine injuries. We applied this to all machinery

accidents, and to the occupational YLD PAFs for injury codes not already covered elsewhere

in alcohol. For YLL we applied a PAF of 0.051 (Driscoll et al. 2001) to the occupational YLL

PAFs for injury codes not already covered elsewhere in alcohol.

Low fruit and vegetable consumption

We used the National Health Survey (ABS 2001c) to estimate distributions of fruit and

vegetable consumption by age and sex in the Australian population. Relative risks came

from Lock and colleagues (2004). We used the CRA theoretical minimum risk distribution for

fruit and vegetable consumption (mean 600, SD 50g/day) as the counterfactual in this

analysis.

Illicit drugs

In addition to being a direct cause of death, illicit drugs are also risk factors for conditions

such as HIV/AIDS, hepatitis, low birth weight, inflammatory heart disease, poisoning, and

suicide & self-inflicted injuries. By definition, heroin, benzodiazepine, cannabis and other

drug dependence and harmful use are due to illicit drug use; therefore the entire burden due

to these conditions was attributed to this risk factor category. For infective endocarditis and

suicide we used the attributable fractions for illicit drugs developed by English and

colleagues (1995). The proportion of inflammatory heart disease that was due to infective

endocarditis was derived from hospital data. The infective endocarditis PAF was then

applied to this proportion only.

The proportion of HIV due to injecting drug use was based on diagnosed HIV from the

Australian HIV Public Access Dataset (National Centre in HIV Epidemiology and Clinical

Research 2005b).We use diagnosed rather than newly acquired HIV, which is in keeping

186

with YLD estimates, and due to the apparent stabilisation of HIV incidence over recent years.

AIDS cases and deaths attributable to injecting drug use were from the Australian AIDS

Public Access Dataset (National Centre in HIV Epidemiology and Clinical Research 2005a).

Time to death (year of death minus year of AIDS diagnosis) was added to the midpoint of

the age at diagnosis range to approximate age range at death. For those age-at-death ranges

available in the AIDS Public Access Dataset, we used the age-specific proportion attributable

to injecting drug use. For all other ages we applied the all-age proportion. For cases of HIV

and AIDS, and AIDS deaths, we assumed that all cases with exposure category ‘male

homosexual contact and injecting drug use’ were attributable to male homosexual contact.

The proportion of newly acquired hepatitis B and C cases due to injecting drug use was from

the HIV/AIDS, viral hepatitis and sexually transmissible infections in Australia Annual

Surveillance Report 2004 (National Centre in HIV Epidemiology and Clinical Research 2004).

The proportion of road traffic accidents due to illicit drug use was derived from Drummer

and colleagues (2004). We applied the methodology used by Ridolfo and Stevenson on

earlier data from Drummer (1994).

For low birth weight we used prevalence of cannabis and opioid diagnosis during pregnancy

in New South Wales and relative risks from Burns and colleagues (2006). The relative risk for

antepartum haemorrhage attributable to illicit drug use was from English and colleagues

(1995), with the prevalence being heroin or cocaine use in past 12 months for females aged

15–49 years from the NDSHS 2004.

The odds ratio for schizophrenia attributable to cannabis use was from Semple and

colleagues (2005). This odds ratio is the result of a meta-analysis of seven studies with

different classifications of psychosis and cannabis use. Despite these differences, there was

consistency in the unadjusted odds ratios. We used prevalence of daily cannabis use over the

last 12 months from the 2004 NDSHS (AIHW & DoHA 2005) to calculate the PAF to be

applied to schizophrenia.

Occupational exposures and hazards

The attributable burden of occupational exposures and hazards was based on the following

methods. Work-related fatal injuries were derived from the National Worker’s

Compensation Statistics Database accessed online via National Occupational Health and

Safety Commission (NOHSC) Online Statistics Interactive (NOSI)

<www.nosi2.nohsc.gov.au/>. Since compensation statistics do not cover all occurrences of

occupational injury deaths, we inflated these figures according to a study carried out by

Driscoll and colleagues (AIHW: Driscoll et al. 2004), that investigated the coverage of workrelated

traumatic deaths by official occupational health and safety and compensation

agencies in Australia. Work-related deaths by mechanism, nature and industry from the

NOSI database were inflated according to the proportion of all work-related deaths in 1989–

92 covered by compensation agencies by industry (Table 3 in AIHW: Driscoll et al. 2004).

In the absence of more reliable information, the attributable fractions for non-fatal injuries

were derived from an analysis of the National Hospital Morbidity Database 2002–03. For

each age–sex–injury group, the attributable fraction for occupational injuries was estimated

as the ratio of hospital episodes where ‘workplace’ was specified as the place where the

injury occurred to the total hospital episodes where a place of occurrence was specified.

Where possible we derived non-injury attributable fractions by following the CRA methods

(Concha-Barrientos et al. 2004). This produced age- and sex-specific attributable fractions for

187

lung cancer, leukaemia, COPD, asthma, adult onset hearing loss, and chronic back pain

(which we also applied to slipped disc). For each of the remaining cancer categories, we

derived attributable fractions from a study carried out for the National Institute of

Occupational Health and Safety (Kerr et al. 1996). This study also provided attributable

fractions for a number of other chronic diseases, including neurological disorders,

cardiovascular diseases, chronic respiratory diseases and renal disease. Attributable fractions

for osteoarthritis were derived separately, based on relative risks of self-reported arthritis for

blue collar workers compared to managers, administrators and professionals (AIHW: Turrell

et al. 2006).

Child sexual abuse and intimate partner violence

Girls that experience child sexual abuse are more likely to experience intimate partner

violence than non-abused girls (Mouzos & Makkai 2004). Women that experience multiple

types of abuse, including child sexual abuse and intimate partner violence, have a higher risk

of depression than those subject to only one form of abuse (Arias 2004; Messman-Moore et al.

2000; Nicolaidis et al. 2004). The 2001 Victorian Burden of Disease Study produced estimates

of the burden attributable to intimate partner violence but did not calculate the burden

attributable to child sexual abuse (DHS 2005; Vos et al. in press). Conversely the CRA project

(Andrews et al. 2004) produced estimates of the burden attributable to child sexual abuse but

not intimate partner violence. In this study we estimated the burden attributable to child

sexual abuse and intimate partner violence. Further, to avoid over-estimating the burden

when both of these risk factors are present we estimated an adjusted relative risk to account

for the combined exposure state of having experienced both child sexual abuse and intimate

partner violence.

We estimated the prevalence of ‘intimate partner violence without child sexual abuse’ and

‘child sexual abuse and intimate partner violence combined’ from the Women’s Safety

Survey (ABS 1996). We used two categories of exposure to intimate partner violence, namely

physical or sexual violence by a partner in the last 12 months, and physical or sexual violence

by a partner more than 12 months ago. Given that the Women’s Safety Survey asks only one

question regarding child sexual abuse (‘Whether experienced sexual abuse when a child’) we

used the CRA project priors for Australia for the prevalence of child sexual abuse (based

upon epidemiological studies) and assumed no trend in prevalence of child sexual abuse. We

subtracted the prevalence of ‘child sexual abuse and intimate partner violence combined’

from the child sexual abuse priors to estimate the prevalence of child sexual abuse without

intimate partner violence.

Messman-Moore and colleagues (2000) looked at the mean psychological functioning indices

for women who had experienced (a) both contact child sexual abuse and adult victimisation

(revictimisation); (b) adult victimisation only (multiple or once only); (c) contact child sexual

abuse only; and (d) no abuse history. From these group means and standard errors we

calculated an effect size using Hedges’ adjusted g for standardised mean difference (Egger et

al. 2001). We then converted the effect sizes into odds ratios for risk of depression, anxiety

and post-traumatic stress disorder by exposure group using the methods described by

Hasselblad and Hedges (1995).

These odds ratios, along with relative risks for contact child sexual abuse from the CRA

project (Andrews et al. 2004), and relative risks for intimate partner violence from the

Women’s health Australia study (see DHS 2005: page 29) were then used to derive relative

188

risks for ‘contact child sexual abuse only’, ‘intimate partner violence only’, and ‘child sexual

abuse and intimate partner violence combined’.

Since Messman-Moore and colleagues (2000) define child sexual abuse as contact only, for

non-contact child sexual abuse we used the CRA project relative risks and prevalence for

that category unadjusted. In our main results we combined anxiety and depression together

into one category. We therefore found the mean relative risk from the derived relative risks

for depression, anxiety, and post-traumatic stress disorder symptoms. We applied the same

relativities from the anxiety and depression relative risks for child sexual abuse only,

intimate partner violence only, and combined child sexual abuse and intimate partner

violence, to the intimate partner violence and child sexual abuse relative risks for other

conditions (alcohol use disorders, other drug use disorders, and self-inflicted injuries).

For ease of reporting, the population attributable fraction calculated for the ‘combined child

sexual abuse and intimate partner violence category’ was proportionately redistributed to

either child sexual abuse or intimate partner violence. To calculate the population

attributable fractions for those disease categories that only apply to intimate partner violence

(smoking, cervical cancer, sexually transmitted diseases, eating disorders and physical

injuries) we used the relative risks for intimate partner violence from the Women’s health

Australia study, and the prevalence of intimate partner violence (including those women

who may have also experience child sexual abuse) from the Women’s Safety Survey. The

proportion of homicide due to intimate partner violence (52%) was from the 2003–2004

National Homicide Monitoring Program Annual Report (Mouzos 2005). Violence YLD was

based on the proportion of hospitalisations for assaults where the relationship of the victim

of assault to the perpetrator was recorded as spouse or domestic partner (including exspouse

and ex-partner). The assaults where this relationship was unspecified were

proportionately redistributed.

Due to a lack of data on the prevalence of intimate partner violence among males, and on the

related health outcomes, for males we only estimated the burden due to child sexual abuse.

Analyses were based on methods developed for the CRA project described elsewhere

(Andrews et al. 2004). We used the CRA priors for Australia for the prevalence of male child

sexual abuse (based upon epidemiological studies).

Urban air pollution

Numerous studies have documented that urban air pollution has a range of effects on health,

from irritated eyes to death. The effects of short-term exposure are generally demonstrated

through time-series studies on daily events (for example mortality, hospitalisations,

emergency department attendance) (Cohen et al. 2004; Simpson et al. 2005a, 2005b). The

effects of long-term exposure have been demonstrated in large cohort and cross-sectional

studies, mainly in the US and Europe (Cohen et al. 2004; Pope et al. 2002). We estimated the

burden due to both long- and short term exposure to urban air pollution, and present the

results for long-term exposure only as a minimum estimate, and the combination of longand

short-term exposure as a more inclusive but less certain higher estimate.

Long-term exposure

For chronic exposure to urban air pollution, our analyses are based on methods developed

for the CRA project (Cohen et al. 2004). The main data inputs were: (a) annual 24-hour

average particulate matter concentrations (particulate matter with an aerodynamic diameter

189

10 and PM2.5) as an indicator of exposure to pollution

from combustion sources; and (b) information on the relative risk of mortality. In the CRA

method, the population attributable fraction was calculated from these inputs as the

difference in disease experience in a population and the hypothetical disease experience if

the population were exposed to the hypothetical minimum of particulate matter (PM2.5

7.5􀂗g/m3; PM10 15􀂗g/m3). However, there is evidence that there may be no safe level of

exposure to particulate matter (WHO Europe 2004). We therefore set the theoretical

minimum to zero in our analyses.

Our estimates for long-term exposure are based on the contributions of two health outcomes:

cardiopulmonary disease and lung cancer in adults aged 30 years and older. Attributable

burden was estimated using risk coefficients from a large cohort study of adults in the

United States (Pope et al. 2002). We did not use the CRA method of attributing acute

respiratory infection in children aged 0–4 years as this method applies a relative risk based

on daily exposure to annual exposure levels. Given the availability of daily urban air

pollution data in Australia, and more appropriate relative risk estimates from Australian

pollution concentration and mortality data, we used the estimates generated using the shortterm

effects methods described below.

We based exposure on annual mean levels for 2002 in the following urban areas: Sydney,

Newcastle, Wollongong, Melbourne, Geelong, Brisbane, Perth, Adelaide, Canberra

(including Queanbeyan), and Hobart. Annual concentrations were derived from data

supplied by the state and territory environmental protection authorities, except for Adelaide

and Hobart where we used published estimates (DPIWE 2004; Gooding & Riordan 2004).

PM2.5 concentration was not available for Geelong, Hobart or Canberra. For Geelong, we

estimated the concentration from Melbourne’s PM10:PM2.5 ratio. For Hobart and Canberra,

we based our estimates on the average PM10:PM2.5 ratio for those cities with original data

(that is, Brisbane, Melbourne, Perth, Sydney, Adelaide, Newcastle and Wollongong). Due to

temporal trends in particulate matter concentration, the linking of current exposure to

chronic outcomes may underestimate the attributable burden if exposure levels were higher

in the past. However, the use of recent exposure data is in keeping with the CRA methods.

Short-term exposure

Short-term exposure to urban air pollution has been associated with day-to-day variations in

hospital admissions and mortality (Simpson et al. 2005a, 2005b). However, translating these

findings into burden of disease estimates is not straightforward. The difficulty with

estimating attributable morbidity is that published risks are established for the impact on

hospitalisations only. An increase in hospitalisations for causes related to urban air pollution

is likely to largely reflect exacerbation of existing disease rather than new disease events. Our

YLD estimates are based on incident cases and their average duration at a particular level of

severity. Thus the impact of urban air pollution on morbidity needs to be estimated as either

a proportion of new cases of disease or a worsening of the condition for an undefined period

of time. Until these methodological issues can be resolved we consider only a mortality

component of the short-term health consequences of urban air pollution.

The problem with attributing mortality to the short-term impact of urban air pollution is that

there is equivocal evidence regarding the extent of ‘harvesting’, that is, imminent deaths

brought forward by only a short period of time (less than a month) that were imminent

anyway, or ‘new deaths’ that would not have occurred in the absence of urban air pollution.

This has a major bearing on our estimates of YLL: if harvesting occurs, YLL will be only a

of less than 10 and 2.5 micrometres, P M

190

fraction of that normally calculated for each death. There is much debate in the literature on

this topic. There are some arguments that harvesting does not play a role in the effects of

urban air pollution. For instance there is an increase in deaths when longer lags between

exposure and outcomes (up to 4 months) of urban air pollution are estimated, rather than a

decrease (Schwartz 2001; Zeger et al. 1999). (The need to control for seasonal variation in

these analyses makes it difficult to extend these analyses over the longer term as longer lags

become strongly correlated with seasonal changes). This finding has been interpreted to

indicate that harvesting is not an important issue. However, it could also be the case that

urban air pollution exposure leads to chronic rather than acute effects on mortality. A further

argument put forward by the same authors is that the largest increase in deaths was seen in

people dying outside a hospital, while one would have expected a greater increase in

hospital deaths if harvesting were bringing deaths forward in people who were already ill.

The authors do not comment, however, on whether this may be due to the protective effect

of the hospital environment. We concluded that there is no consensus on the relative

contribution of deaths brought forward by urban air pollution nor on the size of the true

acute impact on mortality. We therefore present the chronic impact as a lower estimate of the

burden due to urban air pollution and add an alternative estimate of the combined shortterm

and long-term effects, ignoring any harvesting, as an upper bound.

Recent Australian research has provided the most applicable risk coefficients describing the

effect of short-term exposure to urban air pollution on mortality (Simpson et al. 2005b). We

applied these to daily urban air pollution data to estimate the attributable mortality burden

of this risk. Following expert advice, our estimates were based on an averaged 0–1 day lag

(that is, exposure to urban air pollution on the day of death and the day before death) of the

contributions of two pollutants to two causes of death: all cause mortality (excluding

accidental and other external causes of death) due to particle exposure (in units of light

scattering by nephlometry, bsp), and respiratory deaths due to exposure to ozone. The choice

of including these two pollutants and excluding others was made after discussion with the

researchers (Simpson, Williams and Barnett) and justified by the finding that the impact on

mortality of NO2, CO and particles largely overlaps and hence including all three would lead

to overestimation. The impact of SO2 is considered small in Australia but ozone has a

significant impact on respiratory mortality independent of that of other pollutants.

Estimates were calculated with a theoretical minimum exposure level of zero. This is based

on evidence that at the population level there appears to be no safe level of exposure to

particles or ozone (WHO Europe 2004).

A decision was made to work with exposure data from 2002 rather than 2003 (the reference

year for our study) because 2003 is considered an outlier year by the environmental

protection authorities for pollutant readings. Daily urban air pollution data were supplied by

the Victorian, New South Wales, Australian Capital Territory, Queensland and Western

Australian environmental protection authorities. We calculated a PAF for each day by urban

area, pollutant, and underlying cause of death, with the assumption that the entire

population of that urban area was exposed. This was applied to daily 2002 mortality data,

and aggregated to age- and sex-specific annual PAFs. We aggregated the number of deaths

and YLL attributable to urban air pollution in specific areas (Sydney, Newcastle,

Wollongong, Melbourne, Geelong, Brisbane, Perth, Adelaide, Canberra including

Queanbeyan, and Hobart), calculated this as a proportion of all deaths or YLL in Australia

and, finally, applied this proportion to 2003 mortality estimates.

191

We did not gain access to daily Tasmanian or South Australian urban air pollution data.

Particle levels for Adelaide and Hobart were therefore extrapolated from published annual

mean PM10 levels (Air Monitoring Unit, EPA SA 2003; DPIWE 2004), and the average ratio of

bsp:PM10 for Brisbane, Sydney and Melbourne from Simpson and colleagues (2005b). The

ratio of the extrapolated mean bsp for Adelaide and Hobart to the annual mean bsp level for

the cities for which we had detailed exposure data was then applied to the annualised PAF

for these cities to extrapolate the PAFs for the two cities with missing exposure data. Ozone

levels for Adelaide were based on the published average for 2002 (Gooding & Riordan 2004).

Ozone is not routinely monitored in Hobart (DPIWE 2006); we therefore did not include this

region in our analysis of respiratory deaths due to ozone exposure.

Unsafe sex

All sexually transmitted diseases were attributed to unsafe sex. The PAFs for HIV/AIDS and

hepatitis B and C due to unsafe sex were derived as described in the section on illicit drugs.

Previous Australian and Victorian burden of disease studies have used a PAF of 0.90 for

cervical cancer. In this study we attributed all cervical cancer to sexual transmission of the

human papilloma virus. Munoz and colleagues (2003) found that 90.7% cases had HPV DNA

detected. Similarly, in a meta-analysis Clifford and colleagues (2003) found that HPV DNA

was present in 80–89% of cases. However, research by Walboomers and colleagues (1999), in

which they revisited a previous study, suggests that nearly all cases that were negative for

HPV DNA were false negatives. They revised up the estimates of cases testing positive for

HPV DNA from 93% to 99.7%. Bosch and Munoz (2002) suggest that in most studies where

5–15% of cases are negative for HPV these are false negatives.

Osteoporosis

Osteoporosis causes no disability or death per se; it does, however, increase the risk of

fracture. Therefore we treated osteoporosis as a risk factor in this study rather than as a

disease in its own right, as was done in the previous Australian burden study. The WHO

Task-Force for Osteoporosis recommends that the condition be defined by level of bone

mineral density (BMD). We therefore based our PAF calculations on the population

distribution of BMD, and relative risks associated with decreasing BMD.

In Australia there are two large studies that have measured population BMD, one based in

Geelong and the other in Dubbo. Both the Geelong Osteoporosis Study and the Dubbo

Osteoporosis Epidemiology Study state that the population they cover is representative of

the Australian population (Nguyen et al. 2001; Sanders et al. 1998). Mean BMD and standard

deviations (SDs) for the Geelong and Dubbo studies were supplied by the study custodians.

We used Geelong data for ages <60 and combined Geelong and Dubbo data for 60 years or

over by fitting a Weibull distribution. From this distribution we plotted BMD by age for ages

25 years or over and fitted a polynomial distribution (R2=0.998). We then predicted mean

BMD from this equation for 5-year age groups from 60 years.

For males, we assumed that the difference between the Dubbo and Geelong BMD means for

women would also apply to males if Geelong data were available. We therefore increased

Dubbo means by the ratio of female Dubbo sampled mean to the combined mean. We

assumed deviations from the line were sampling error, and predicted mean BMD by age

group from the fitted quadratic equation (R2=0.925). We assumed the SD for Dubbo applied.

192

The WHO Task-Force for Osteoporosis recommends that the condition be defined in

Caucasian women as a BMD 2.5 SDs or more below the young female reference mean

(Genant et al. 1999). The Australia and New Zealand Bone and Mineral Society and

Osteoporosis Australia recommended that data from the Geelong Osteoporosis Study be

used to establish a standardised reference range for Australia (Henry et al. 2004). We

therefore used the mean BMD and SD for young women aged 20–29 from this study as the

theoretical minimum, and also used this population for the osteoporosis cut-off (Henry et al.

2004).

There is currently no Australian reference mean BMD and SD for young adult men. We

estimated these values by multiplying the Australian young female mean and SD (Henry et

al. 2004) by the ratio of male to female mean and SD from the USA’s National Health and

Nutrition Examination Survey (NHANES) (Looker et al. 1998). The NHANES used Hologic

densitometers while both the Dubbo and Geelong studies used Lunar densitometers. These

machines do not give standardised results. We therefore converted the Hologic estimates to

Lunar by applying the formula available at <www.courses.washington.edu/bonephys/

opBMDs.html>.

Relative risks and odds ratios from a number of studies were pooled to estimate the relative

risk of low impact fracture per 0.1g/cm2 decrease in BMD measured at the femoral neck

(EPOS Group 2002; Fujiwara et al. 2003; Kroger et al. 1995; Nguyen et al. 2005a, 2005b;

Papaioannou et al. 2005; Schott et al. 2005; Schuit et al. 2004; Stone et al. 2003). Where a study

used Hologic or Norland densitometers, and the relative risk was per SD change in BMD, we

converted the study’s SD estimates to Lunar.

We derived PAFs for a number of fracture sites. Where possible these sites were linked

directly to a single nature of injury category. In some cases (for example hip) we applied the

PAF to a proportion of a category based on the distribution of fracture sites in the National

Hospital Morbidity Database 2002–03. Since most studies that we included in the calculation

of relative risks excluded fractures resulting from high impact causes, we applied the PAFs

to fractures resulting from falls, striking and crushing accidents, and other unintentional

injuries.

For attributable YLL, we applied the site-specific fracture YLD PAFs to the site-specific

mortality distribution for vertebral, pelvis and femur fracture to derive a site-specific YLL

PAF. This was applied to deaths with an underlying cause of falls, striking and crushing

accidents, other unintentional injuries, ill-defined falls or osteoporosis, where a fractured

spine, pelvis or femur was mentioned. If more than one fracture was mentioned we applied

the larger PAF, that is, for fractured pelvis and femur we applied the PAF for femur. We

assumed that all deaths with an underlying cause of osteoporosis but no mention of

vertebral, pelvis, or femur fracture, were attributable to osteoporosis. To determine the

burden of disease code-specific YLL PAF for osteoporosis we calculated the proportion of

burden of disease code-specific deaths attributable to osteoporosis. Osteoporosis and ill defined

fall deaths were redistributed to falls. If we were to limit the deaths attributable to

osteoporosis to only those that were coded to osteoporosis, the overall number of deaths

would have been considerably smaller.

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Table A2.3: Definitions, theoretical minima, health outcomes and data sources for 14 selected health risks

Health risk

Exposure

variable

Theoretical

minimum Outcomes

Sources for

exposure

estimates Sources for hazard estimates

High blood

pressure

Level of usual

systolic blood

pressure

115 (SD 6)

mmHg

Ischemic heart disease, stroke,

hypertensive heart disease

AusDiab study

(Dunstan et al.

2002)

Meta-analysis of 61 cohort studies with

1,000,000 North American and European

participants (Prospective Studies

Collaboration (Lawes et al. 2003))

High blood

cholesterol

Level of usual

total blood

cholesterol

3.8 (SD 0.6)

mmol/L (147 (SD

23) mg/dL)

Ischemic heart disease, ischemic stroke AusDiab study

(Dunstan et al.

2002)

Meta-analysis of 10 cohorts with 490,000

North American and European

participants, and 29 cohorts with 350,000

participants from the Asia-Pacific region

High body mass

index (BMI)

Body mass

index, BMI

(weight over

height

squared)

21 (SD 1) kg/m2 Ischemic heart disease, stroke,

hypertensive heart disease, diabetes,

osteoarthritis, endometrial cancer, kidney

cancer, colon cancer, post-menopausal

breast cancer

AusDiab study

(Dunstan et al.

2002)

Meta-analysis of 33 cohorts with 310,000

participants for cardiovascular disease

risks, 27 cohorts for cancer risks, and

systematic review of cohort studies for

diabetes risk

Low fruit and

vegetable

consumption

Fruit and

vegetable

intake per day

600 (SD 50) g

intake per day for

adults

Ischemic heart disease, stroke, colorectal

cancer, gastric cancer, lung cancer,

oesophageal cancer

National Health

Survey 2001

(ABS 2001c)

Systematic review and new meta-analysis

of published cohort studies

Osteoporosis Bone mineral

density of the

femoral neck

Males 1.107 (SD

0.140) g/cm2;

Females 1.018

(SD 0.127) g/cm2

With

osteoporosis

defined 2.5 or

more SD below

this mean

Fractured hip, femur, humerus, clavicle,

forearm/wrist, elbow, spine, rib, pelvis,

lower leg, patella, foot, heel, toe, hand,

finger from falls, striking and crushing

accidents, other unintentional injuries

Dubbo

Osteoporosis

Epidemiology

Study (Nguyen

2005) and

Geelong

Osteoporosis

Study

(Kotowicz

2005)

Pooled analysis of 10 studies (EPOS

Group 2002; Fujiwara et al. 2003; Kroger

et al. 1995; Nguyen et al. 2005a, 2005b;

Papaioannou et al. 2005; Schott et al.

2005; Schuit et al. 2004; Stone et al.

2003)

(continued)

194

Table A2.3 (continued): Definitions, theoretical minima, health outcomes and data sources for 14 selected health risks

Health risk

Exposure

variable

Theoretical

minimum Outcomes

Sources for

exposure

estimates Sources for hazard estimates

Physical inactivity Four

categories:

inactive,

insufficient,

recommended

level and

highly active

All in ‘highly

active’ group

Ischemic heart disease, stroke, breast

cancer, colon cancer, diabetes

National Health

Survey 2001

(ABS 2001c)

Systematic review of published literature

and new meta-analysis of cohort studies

Past smoking No smoking COPD, cancers of mouth, oesophagus,

lung, pancreas, larynx, bladder, kidney,

stomach and uterus

Peto–Lopez

method

Systematic reviews by English and

colleagues (1995) and Ridolfo and

Stevenson (AIHW: Ridolfo & Stevenson

2001)

Current daily

smokers

No smoking Ischemic heart disease, stroke, peripheral

vascular disease, Parkinson’s disease,

pneumonia (adults), fire injuries, macular

degeneration

National Health

Survey 2001

(ABS 2001c)

Systematic reviews by English and

colleagues (1995) and Ridolfo and

Stevenson (AIHW: Ridolfo & Stevenson

2001); Tomany and colleagues (2004) for

age related macular degeneration

Passive

smoking

No smoking Ischemic heart disease, stroke National Health

Survey 1995

(ABS 1995)

Systematic reviews by English and

colleagues (1995) and Ridolfo and

Stevenson (AIHW: Ridolfo & Stevenson

2001)

Tobacco

Maternal

smoking;

smoking while

pregnant

No smoking Asthma, pneumonia (children), sudden

infant death syndrome, otitis media, low

birth weight

National Health

Survey 2001

(ABS 2001c),

Australia’s

Mothers and

Babies 2003

(AIHW: Laws &

Sullivan 2005)

Systematic reviews by English and

colleagues (1995) and Ridolfo and

Stevenson (AIHW: Ridolfo & Stevenson

2001); US Surgeon General’s Report on

Involuntary exposure to tobacco smoke (US

Department of Health and Human Services

2006); systematic review by Anderson and

Cook (1997).

(continued)

195

Table A2.3 (continued): Definitions, theoretical minima, health outcomes and data sources for 14 selected health risks

Health risk

Exposure

variable

Theoretical

minimum Outcomes

Sources for

exposure

estimates Sources for hazard estimates

Alcohol Average

number of

standard

drinks per

day

Low level of

drinking

Cancers of the mouth and oropharynx,

oesophagus, liver, larynx and breast;

inflammatory heart disease, hypertensive

heart disease, ischemic heart disease,

stroke, alcohol dependence and harmful

use, gallbladder and bile duct disease,

pancreatitis, road traffic accidents, falls,

fires/burns/scalds, drowning, machinery

accidents, suffocation and foreign bodies,

suicide and self-inflicted injuries, homicide

and violence, occupational injuries

National

Health Survey

2001 (ABS

2001c)

Systematic reviews by English and

colleagues (1995) and Ridolfo & Stevenson

(AIHW: Ridolfo & Stevenson 2001); the

National Coroners Information System

(Driscoll et al. 2001, 2004) for alcohol-related

drownings and occupational YLL; fire injuries

and fatalities pooled results from published

studies; scalds and burns from Levy and

colleagues (2004)

Illicit drug use Use of illicit

drugs

Abstinence Heroin or polydrug, benzodiazepine,

cannabis, and other drug dependence and

harmful use

AusBoD drug

use and

dependence

models

PAF = 1 by definition

Use of illicit

drugs

Abstinence HIV/AIDS, hepatitis B, hepatitis C,

inflammatory heart disease, suicide and

self-inflicted injuries, road traffic accidents

Population

attributable

fraction direct

from the

literature

Incorporated findings from a multi-centre

case-control study on 3,398 fatally injured

drivers over Victoria, NSW and Queensland

(examining psychoactive drugs); viral

hepatitis and sexually transmissible

infections from Australia Annual Surveillance

Report 2004; and systematic literature

reviews by English and colleagues (1995)

and Ridolfo and Stevenson (AIHW: Ridolfo &

Stevenson 2001)

Daily

cannabis use

No cannabis

use, or use less

often than daily

Schizophrenia National Drug

Strategy

Household

Survey 2004

Meta-analysis of 7 published case-control or

cohort studies (examining link between

psychosis and cannabis use).

(continued)

196

Table A2.3 (continued): Definitions, theoretical minima, health outcomes and data sources for 14 selected health risks

Health risk

Exposure

variable

Theoretical

minimum Outcomes

Sources for

exposure

estimates Sources for hazard estimates

Unsafe sex Unprotected

sex

Abstinence/prote

cted sex

Sexually transmissible diseases, abortion,

cervical cancer, HIV/AIDS, hepatitis B & C

AusBoD

sexually

transmissible

diseases,

abortion, and

cervical

cancer

models; PAF

direct from

the literature

PAF=1 (sexually transmissible diseases,

abortion, cervical cancer); HIV/AIDS

proportion from the Australian HIV and AIDS

Public Access Datasets (National Centre in

HIV Epidemiology and Clinical Research

2005a, 2005b); hepatitis B & C fraction from

the National Centre in HIV Epidemiology and

Clinical Research (National Centre in HIV

Epidemiology and Clinical Research 2004)

Child sexual

abuse

Non-contact

only, contact

only,

intercourse

No abuse Anxiety & depression, alcohol dependence &

harmful use, heroin or polydrug use &

dependence, benzodiazepine dependence &

harmful use, cannabis dependence &

harmful use, other drug dependence &

harmful use, suicide and self-inflicted injuries

CRA priors

for Australia

Systematic review and new meta-analysis of

published studies (Andrews et al. 2004)

Intimate partner

violence

Physical or

sexual

violence by

current or

previous

partner

No history of

sexual or

physical violence

by an intimate

partner

Anxiety & depression, alcohol dependence &

harmful use, heroin or polydrug use &

dependence, benzodiazepine dependence &

harmful use, cannabis dependence &

harmful use, other drug dependence &

harmful use, suicide and self-inflicted

injuries, tobacco smoking, cervical cancer,

syphilis, chlamydia, gonorrhoea, other

sexually transmissible diseases, anorexia

nervosa, bulimia nervosa, other eating

disorders, falls, other unintentional injuries,

homicide & violence

Women’s

Safety

Survey 1996

(ABS 1996)

Australian Longitudinal Study on Women’s

Health (Brown et al. 1999); 2003–2004

National Homicide Monitoring Program

(NHMP) Annual Report (Mouzos 2005);

National Hospital Morbidity Database 2002–

03 (AIHW 2003a)

(continued)

197

Table A2.3 (continued): Definitions, theoretical minima, health outcomes and data sources for 14 selected health risks

Health risk

Exposure

variable

Theoretical

minimum Outcomes

Sources for

exposure

estimates Sources for hazard estimates

Occupational

exposures and

hazards

Exposure in

the

workplace to

diseasecausing

agents such

as carbon

monoxide,

dyes,

inorganic and

organic

dusts,

pesticides,

metals, metal

fumes,

petrochemica

ls, plastics,

solvents,

isocyanate

and

nitroglycerine

or

nitroglycerol

No exposure All accidents, intentional and unintentional

injuries, cancers, heart disease, neurological

disorders, chronic respiratory disorders,

renal disease, osteoarthritis, slipped disc,

occupational overuse syndrome

National

Worker’s

Compensation

Statistics

Database

2003, National

Coroners

Information

system 2003,

and Best

estimates of

the magnitude

of health

effects of

occupational

exposure to

hazardous

substances

(Kerr et al.

1996)

Systematic review of published literature,

hospital inpatient data, mortality datasets,

National Health Survey results, workers

compensation data, notified industrial

accident reports and special disease registry

datasets

Urban air

pollution

Exposure to

particulate

matter and/or

oxygen (i.e.

total

population of

cities of

interest)

No exposure Short-term exposure: cardiovascular,

respiratory, and other deaths

Long-term exposure: lung cancer, ischemic

heart disease, stroke, inflammatory heart

disease, hypertensive heart disease, COPD

Assume all

residing in

relevant

geographical

areas exposed;

particulate and

ozone levels

from state

environmental

protection

agencies

Time series analysis of short-term effects of

urban air pollution in four Australians cities

(Simpson et al. 2005a); long-term exposure

effects from Pope and colleagues (2002)

198

Table A2.4: Prevalence of health risks by age and sex

Males Females

Health risk Category 0–4 5–14 15–29 30–44 45–59 60–69 70–79 80+ 0–4 5–14 15–29 30–44 45–59 60–69 70–79 80+

mean . . Blood pressure (mmHg) . . . . 124 131 140 148 154 . . . . . . 115 126 138 146 150

SD . . . . . . 11 16 17 19 19 . . . . . . 12 17 19 22 21

Blood cholesterol (mmol/L) mean . . . . . . 5.5 5.8 5.6 5.6 5.3 . . . . . . 5.2 5.8 6.0 6.1 5.9

SD . . . . . . 1.0 1.1 0.9 0.9 1.0 . . . . . . 1.0 1.1 0.9 1.0 1.0

BMI (kg/m2) mean . . . . . . 26.8 27.5 27.2 27.1 25.8 . . . . . . 25.4 27.2 28.5 27.0 24.9

SD . . . . . . 4.1 4.0 3.7 3.8 3.5 . . . . . . 5.4 5.7 5.8 5.2 4.5

Fruit and vegetable mean . . . . 445 452 496 538 538 538 . . . . 484 506 569 602 577 577

consumption (g/day)

SD . . . . 241 235 245 230 219 219 . . . . 237 228 240 234 217 217

Bone mineral density

(BMD) (g/cm3) Mean

. .

. . . . . . . . 0.93 0.87 0.77 . . . . . . . . . . 0.85 0.78 0.66

SD . . . . . . . . . . 0.15 0.14 0.16 . . . . . . . . . . 0.13 0.12 0.12

High . . . . 10% 3% 3% 1% 1% 0% . . . . 4% 2% 1% 1% 0% 0%

Recommended . . . . 47% 37% 37% 41% 44% 30% . . . . 37% 32% 35% 38% 27% 17%

Insufficient . . . . 23% 29% 29% 26% 22% 21% . . . . 35% 38% 33% 28% 28% 24%

Physical activity (%

population in categories)

Inactive . . . . 20% 31% 32% 33% 33% 49% . . . . 25% 28% 30% 33% 45% 59%

Current smoker . . . . 30% 31% 23% 16% 9% 7% . . . . 25% 25% 18% 12% 9% 2%

Prenatal exposure 16% . . . . . . . . . . . . . . 16% . . . . . . . . . . . . . .

Tobacco (% population in

categories)

Maternal smoking 27% . . . . . . . . . . . . . . 27% . . . . . . . . . . . . . .

Abstainer . . . . 37% 35% 33% 43% 49% 56% . . . . 57% 59% 58% 66% 73% 76%

Low . . . . 48% 51% 52% 43% 45% 40% . . . . 35% 32% 32% 25% 20% 22%

Hazardous . . . . 7% 7% 8% 8% 4% 2% . . . . 7% 7% 7% 7% 6% 2%

Alcohol (% population in

categories)

Harmful . . . . 7% 7% 7% 6% 2% 2% . . . . 1% 2% 3% 2% 1% 0%

(continued)

199

Table A2.4 (continued): Prevalence of health risks by age and sex

Males Females

Health risk Category 0–4 5–14 15–29 30–44 45–59 60–69 70–79 80+ 0–4 5–14 15–29 30–44 45–59 60–69 70–79 80+

Daily cannabis use . . . . 4% 4% 1% 0% 0% 0% . . . . 2% 2% 0% 0% 0% 0%

Prenatal exposure

– opioids 0% . . . . . . . . . . . . . . 0% . . . . . . . . . . . . . .

Prenatal exposure

– cannabis 1% . . . . . . . . . . . . . . 1% . . . . . . . . . . . . . .

Maternal use –

heroin . . . . . . . . . . . . . . . . . . . . 0% 0% 0% 0% 0% 0%

Illicit drugs (% population

in categories)

Maternal use –

cocaine . . . . . . . . . . . . . . . . . . . . 2% 1% 0% 0% 0% 0%

No abuse 100% 96% 96% 94% 94% 94% 94% 94% 98% 79% 79% 71% 71% 71% 71% 71%

Non-contact only

CSA 0% 1% 1% 2% 2% 2% 2% 2% 1% 6% 6% 9% 9% 9% 9% 9%

Contact only CSA 0% 2% 2% 3% 3% 3% 3% 3% 1% 11% 12% 16% 16% 16% 16% 16%

Child sexual abuse (%

population in categories)

Intercourse CSA 0% 1% 1% 1% 1% 1% 1% 1% 0% 3% 3% 5% 5% 5% 5% 5%

Intimate partner violence

(% population in

categories)

Sexual or physical

violence . . . . . . . . . . . . . . . . . . . . 15% 22% 21% 10% 10% 10%

Low . . . . 14% 9% 8% 3% 1% 1% . . . . 34% 25% 22% 5% 1% 1%

Moderate . . . . 44% 41% 35% 13% 3% 3% . . . . 18% 17% 18% 4% 1% 1%

Occupational exposure to

ergonomic stressors (%

population in categories)

High . . . . 2% 3% 4% 4% 2% 2% . . . . 0% 0% 0% 0% 0% 0%

Occupational exposure to

ergonomic stressors

(increases risk of

osteoarthritis) (%

population in categories) Blue collar workers . . . . 40% 40% 34% 12% 3% 3% . . . . 8% 9% 10% 3% 1% 1%

(continued)

200

Table A2.4 (continued): Prevalence of health risks by age and sex

Males Females

Health risk Category 0–4 5–14 15–29 30–44 45–59 60–69 70–79 80+ 0–4 5–14 15–29 30–44 45–59 60–69 70–79 80+

85–90 dBA Occupational exposure to . . . . 5% 5% 5% 2% 1% 1% . . . . 4% 3% 3% 1% 0% 0%

noise (% population in

categories) >90 dBA . . . . 4% 4% 3% 1% 0% 0% . . . . 1% 1% 1% 0% 0% 0%

Occupational exposure to Low . . . . 3% 4% 4% 1% 0% 0% . . . . 3% 4% 4% 1% 0% 0%

leukaemogens

(% population in

categories) High . . . . 0% 0% 0% 0% 0% 0% . . . . 0% 0% 0% 0% 0% 0%

Occupational exposure to Low . . . . 21% 28% 23% 8% 2% 2% . . . . 6% 9% 7% 2% 0% 0%

lung carcinogens

(% population in

categories) High . . . . 2% 3% 3% 1% 0% 0% . . . . 1% 1% 1% 0% 0% 0%

Occupational exposure to Low . . . . 18% 27% 25% 11% 4% 4% . . . . 7% 11% 10% 3% 1% 1%

agents causing COPD

(% population in

categories) High . . . . 12% 14% 11% 3% 1% 1% . . . . 1% 2% 2% 0% 0% 0%

Background . . . . 23% 10% 17% 67% 90% 90% . . . . 31% 28% 33% 84% 97% 97%

Administration . . . . 6% 12% 13% 4% 1% 1% . . . . 16% 21% 18% 4% 1% 1%

Technical . . . . 16% 30% 28% 10% 3% 3% . . . . 16% 27% 24% 5% 1% 1%

Sales . . . . 10% 4% 3% 2% 0% 0% . . . . 19% 6% 5% 1% 0% 0%

Agriculture . . . . 2% 3% 4% 4% 2% 2% . . . . 0% 1% 1% 1% 0% 0%

Mining . . . . 1% 1% 1% 0% 0% 0% . . . . 0% 0% 0% 0% 0% 0%

Transport . . . . 6% 8% 9% 3% 1% 1% . . . . 1% 1% 1% 0% 0% 0%

Manufacturing . . . . 31% 28% 21% 7% 1% 1% . . . . 6% 6% 6% 1% 0% 0%

Occupational exposure to

agents causing asthma

(% population in

categories)

Services . . . . 6% 4% 4% 2% 1% 1% . . . . 11% 10% 11% 3% 1% 1%

201

Annex tables

202

Annex Table 1: Disease and injury categories and ICD-10 codes

Cause ICD–10 codes

I. Communicable diseases, maternal and

neonatal conditions

A. Infectious and parasitic diseases

1. Tuberculosis A15–19;B90;K230,673,930;M011,490,900;N330,7401;O980;P370

2. Sexually transmitted diseases(a)

a. Syphilis A50–53;I980;K672;M031,731;N290,742

b. Chlamydia A56;K670;N744

c. Gonorrhoea A54;K671;M730;N743;O982

d. Other sexually transmitted diseases A55,57–64

3. HIV/AIDS B20–24;F024

4. Diarrhoeal diseases A00–09

5. Childhood immunisable diseases

a. Diphtheria A36

b. Whooping cough A37

c. Tetanus A33–35

d. Poliomyelitis A80;B91

e. Measles B05

f. Rubella B06;M014;P350

g. Haemophilus influenzae type b (Hib) A413,492;G000;J051,14,201

6. Meningitis A39;G001–9,03

7. Septicaemia A40,410–2,414–8

8. Arbovirus infection

a. Ross River virus B331

b. Barmah Forest virus A92.8

c. Dengue A90–91

d. Other arbovirus infection A83–84,852,92–99

9. Hepatitis

a. Hepatitis A B15

b. Hepatitis B(b) B16,170,180–1

c. Hepatitis C(c) B171,182

d. Other hepatitis B172–8,188–9,19;P353

10. Malaria B50–54

11. Trachoma A71;B940

12. Other infectious and parasitic diseases A20–32,38,42–48,490–1,493–9,65–70,74–79,81–82,850–1, 858,

86–89;B00–04,07–09,25–30,330,332–8,34–49,55–89,92

(excluding 92.8),941, 948–9,95–99;G01–02,04–

07;K231;M00,010,012–3,015–8, 030

B. Acute respiratory infections

1. Lower respiratory tract infections J10–13,15–18,200,202–9,21–22

2. Upper respiratory tract infections J00–04,050,06

3. Otitis media H65–66

C. Maternal conditions

1. Maternal haemorrhage O441,45–46,67,72

2. Maternal sepsis O411,85–86

3. Hypertensive disorders of pregnancy O10–16

4. Obstructed labour O64–66,711,713

5. Abortion O00–08

(continued)

203

Annex Table 1 (continued): Disease and injury categories and ICD-10 codes

Cause ICD–10 codes

6. Other maternal conditions O09,20–24,26–40,410,418–9,42–43,440,47–63,68–70, 710,712,

714–9,73–82,87–97,981,983–9,99

D. Neonatal causes

1. Birth trauma and asphyxia P03,10–21,24–28

2. Low birthweight P05–07,22

3. Neonatal infections P23,351–2,358–9,36,371–9,38–39

4. Other conditions arising in the perinatal period P04,08,29,50–96

E. Nutritional deficiencies

1. Protein-energy malnutrition E40–45,640;M833;O25

2. Deficiency anaemia D50–53

3. Other nutritional deficiencies E00–02,031,50,51–1,518–9,52–61,630–8,641–9

II. Non-communicable diseases

F. Malignant neoplasms

1. Mouth and oropharynx cancers C00–14

2. Oesophagus cancer C15

3. Stomach cancer C16

4. Colorectal cancer C18–21

5. Liver cancer(d) C22

6. Gallbladder cancer C23–24

7. Pancreas cancer C25

8. Lung cancer C33–34

9. Bone and connective tissue cancer C40–41,490–9

10. Melanoma C43

11. Non-melanoma skin cancers C44

12. Breast cancer C50

13. Cervix cancer C53

14. Corpus uteri cancer C54

15. Ovary cancer C56,570–4

16. Prostate cancer C61

17. Testicular cancer C62

18. Bladder cancer C67

19. Kidney cancer C64–66,68

20. Brain cancer C71

21. Thyroid cancer C73

22. Lymphoma C81–85,96

23. Multiple myeloma C88–90

24. Leukaemia C91–95

25. Larynx cancer C32

26. Eye cancer C69

27. Other malignant neoplasms C17,26–31,37–39,45–48,51–52,577–9,58–60,63,70,72,74–75

G. Other neoplasms

1. Uterine myomas D25

2. Benign neoplasms of meninges and brain D32–33

3. Other benign neoplasms D00–24,26–31,34–48

H. Diabetes mellitus

1. Type 1 diabetes E10

2. Type 2 diabetes E11–13

(continued)

204

Annex Table 1 (continued): Disease and injury categories and ICD-10 codes

Cause ICD–10 codes

I. Endocrine and metabolic disorders

1. Non-deficiency anaemia

a. Haemolytic anaemia D55–58

b. Other non-deficiency anaemia D59–63,640–8

2. Cystic fibrosis E84

3. Haemophilia D66–67,681

4. Other endocrine and metabolic disorders D680,682–9,69–72,730–4,738–9,74–89;E030,032–9,04–07,15–35,

65,660–2,67–77,781–4,786–9,79–83,85,873–4,878,88–90;

D65,735;E668–9,86,870–2,875–7

J. Mental disorders

1. Substance use disorders

a. Alcohol dependence and harmful use(e) E512;F10;G312;X45

b. Heroin or polydrug dependence and harmful

use

F11;X42

c. Benzodiazepine dependence and harmful

use

F13

d. Cannabis dependence and harmful use F12

e. Other drug dependence and harmful use F14–16,18–19

2. Schizophrenia F20–29

3. Anxiety and depression F30,32–39,400–1,410–2,42,431,930

4. Bipolar disorder F31

5. Personality disorders(f) F603

6. Eating disorders

a. Anorexia nervosa F500–1

b. Bulimia nervosa F502–3

c. Other eating disorders F504–9

7. Childhood conditions

a. Attention-deficit hyperactivity disorder F90

b. Autism spectrum disorders F84

8. Other mental disorders F05–09, 402–9,413–9,430,432–9,44–48,51–59,600–2,604–9,

61-69,80–83,88–89,91–92,931–9,94–99

K. Nervous system and sense organ disorders

1. Dementia F00–01,020–1,023,03;G30,310–1,318–9

2. Epilepsy G40–41

3. Parkinson’s disease G20

4. Multiple sclerosis G35

5. Motor neurone disease G122

6. Huntington’s chorea F022;G10

7. Muscular dystrophy G710

8. Sense organ disorders

a. Glaucoma-related blindness H40

b. Cataract-related blindness H25–27

c. Macular degeneration H353

d. Adult-onset hearing loss H90–91

e. Refractive errors H520–7

f. Other vision loss H54

9. Migraine G43

10. Other nervous system and sense organ

disorders

F028,04,70–79;G08–09,11,120–1,128–9,13,21–26,32,36–37,44,

46–70,711–932,72–92,934–9,94–H22;H28–34,350–2,354-9,36,

42–51,53,55–62,67–83,92–95

(continued)

205

Annex Table 1 (continued): Disease and injury categories and ICD-10 codes

Cause ICD–10 codes

L. Cardiovascular disease

1. Rheumatic heart disease I00–09

2. Ischemic heart disease I20–25

3. Stroke G45;I60–69

4. Inflammatory heart disease I30–33,40–42

5. Hypertensive heart disease I11,130,15

6. Non-rheumatic valvular disease I34–39

7. Aortic aneurysm I71

8. Peripheral vascular disease I700–8,720–9,73–74

9. Other cardiovascular disease I26,271,28,43–45,470–1,479,48,491–9,510–4,52,77–84,86–97,

981–8,99

M. Chronic respiratory disease

1. Chronic obstructive pulmonary disease

(COPD)

I270,278–9;J40–44

2. Asthma J45–46

3. Other chronic respiratory diseases J30–39,47–99

N. Diseases of the digestive system

1. Peptic ulcer disease K25–27

2. Cirrhosis of the liver(g) I85;K70,717,721–9,73–74,766–7

3. Appendicitis K35–37

4. Intestinal obstruction K400–1,403–4,410–1,413–4,420–1,430–1,440–1,450–8,460–1,56

5. Diverticulitis K57

6. Gallbladder and bile duct disease K80–83

7. Pancreatitis K85,860–1

8. Inflammatory bowel disease K50–51

9. Vascular insufficiency bowel K55

10. Other digestive system diseases K20–22,238,28–31,38,402,409,412,419,429,439,449,469,52,

58-66, 678,710–6,718–9,720,75,760–5,768–9,77,862–9,

87-91,928–9, 931–8

O. Genitourinary diseases

1. Nephritis and nephrosis(h) I12,131;N00–01,03–16,17–19

2. Benign prostatic hypertrophy N40

3. Urinary incontinence N393–4

4. Infertility N46,97

5. Other genitourinary diseases N02,20–28,291–8,30–32,338–392,34–37,398–9,41–45,47–64,

75-96, 98–99

P. Skin diseases

1. Eczema L20–27

2. Acne L70

3. Psoriasis L40

4. Ulcers L03,088–9,89,97,984

5. Other skin diseases L00–02,04–05,080–1,10–14,28–30,41–68,71–88,90–95,980–3,

985–9,99

Q. Musculoskeletal diseases

1. Rheumatoid arthritis M05–06,080,120,465–8

2. Osteoarthritis M15–19

3. Back pain(i) M469,47,480–3,488–9,538–9,545–9

4. Slipped disc M464,50–51,543–4,961

5. Occupational overuse syndrome

6. Systemic lupus erythematosus (SLE) M32

(continued)

206

Annex Table 1 (continued): Disease and injury categories and ICD-10 codes

Cause ICD–10 codes

7. Gout M10

8. Other musculoskeletal diseases M02,032–6,07,081–9,09,11,121–8,13–14,20–31,33–45,460–3,

484–5,491–8,530–3,540–2,60–72,738,75–79,830–2,834–9,

84-89,901–960,91–95,962–9,99

R. Congenital anomalies

1. Anencephaly Q00

2. Spina bifida Q05

3. Congenital heart disease Q20–28

4. Cleft lip and/or palate Q35–37

5. Digestive system malformations

a. Anorectal atresia Q42

b. Oesophageal atresia Q390–1

c. Other digestive system malformations Q38,392–9,40–41,43–45

6. Urogenital tract malformations

a. Renal agenesis(j) Q60

b. Other urogenital tract malformations(k) Q50–56,61–64

7. Abdominal wall defect Q792–5

8. Down syndrome Q90

9. Other chromosomal disorders Q91–99

10. Other congenital anomalies Q01–04,06–18,30–34,65–78,790–1,796–9,80–89

S. Oral conditions

1. Dental caries K02

2. Periodontal disease K05

3. Edentulism

4. Pulpitis K04

5. Other oral conditions K00–01,03,06–14

Z. Ill-defined conditions

1. Sudden infant death syndrome R95

2. Chronic fatigue syndrome G933;R53

III. Injuries

T. Unintentional injuries

1. Road traffic accidents V011–9,021–9,031–9,041–9,061–9,092–3,104–9,114–9,124–9,

134–9,144–9,154–9,164–9,174–9,184–9,194–9,204–9,214–9,

224–9,234–9,244–9,254–9,264–9,274–9,284–9,294–9,305–9,

315–9,325–9,335–9,345–9,355–9,365–9,375–9,385–9,394–9,

405–9,415–9,425–9,435–9,445–9,455–9,465–9,475–9,485–9,

494–9,505–9,515–9,525–9,535–9,545–9,555–9,565–9,575–9,

585–9,594–9,605–9,615–9,625–9,635–9,645–9,655–9,665–9,

675–9,685–9,694–9,705–9,715–9,725–9,735–9,745–9,755–9,

765–9,775–9,785–9,794–9,803–5,809,811,821–9,830–3,840–3,

850–3,860–4,870–8,892,899;Y85

2. Other transport accidents V010,020,030,040,05,060,090–1,099,100–3,110–3,120–3,130–3,

140–3,150–3,160–3,170–3,180–3,190–3,200–3,210–3,220–3,

230–3,240–3,250–3,260–3,270–3,280–3,290–3,300–4,310–4,

320–4,330–4,340–4,350–4,360–4,370–4,380–4,390–3,400–4,

410–4,420–4,430–4,440–4,450–4,460–4,470–4,480–4,490–3,

500–4,510–4,520–4,530–4,540–4,550–4,560–4,570–4,580–4,

590-3,600–4,610–4,620–4,630–4,640–4,650–4,660–4,670–4,

680–4,690–3,700–4,710–4,720–4,730–4,740–4,750–4,760–4,

770–4,780–4,790–3,800–2,806–8,810,812–9,820,834–9, 844–9,

854–9,865–9,879,88,890–1,893,90–99

3. Poisoning X40–41,43–44,46–49

4. Falls W00–19; M80–82

5. Fires, burns and scalds X00–19

(continued)

207

Annex Table 1 (continued): Disease and injury categories and ICD-10 codes

Cause ICD–10 codes

6. Drowning W65–74

7. Sports injuries W21;X50

8. Natural and environmental factors W53–59,64,85–99;X20–39,51–57

9. Machinery accidents W24,27–31

10. Other unintentional injuries

Suffocation and foreign bodies W44, W75–W84

Adverse effects of medical treatment Y40–Y59, Y60–Y69, Y70–Y84, Y88

Other unintentional injuries n.e.c. W20, W22–W23, W25–W26, W32–W44, W45, W49, W51, W50,

W52, W60, W75–84; X58; Y40–Y59, Y60–Y84, Y86, Y880–Y883

U. Intentional injuries

1. Suicide and self-inflicted injuries X60–84;Y870

2. Homicide and violence X85–Y09;Y871

3. Legal intervention and war Y35–36,890–1

Redistribution categories

1. Pelvic inflammatory disease N70–73,748

2. Unspecified septicaemia A419

3. Hepatitis sequelae B942

4. Neonatal causes coded based on maternal

condition

P00–02

5. Ill-defined nutritional E46,639

6. Ill-defined malignant neoplasms C76–80,97

7. Uterus cancer—unspecified C55

8. Unspecified diabetes mellitus E14

9. Other anaemia D649

10. Smoking listed as cause F17

11. Hypertensive heart and renal disease I132–9

12. Heart failure I50

13. Essential hypertension I10

14. Ill-defined cardiovascular conditions E780,785;I46,472,490,515–9,709

15. Gastric haemorrhage K920–2

16. Ill-defined unintentional accidents (fall if also

fracture)

X59;Y90–98

17. Other accidents—intent undetermined Y20,22–25,28–29,33,34,872,899

18. Road traffic accidents—intent undetermined Y32

19. Poisoning—intent undetermined Y10–19

20. Falls—intent undetermined Y30–31

21. Burns—intent undetermined Y26–27

22. Drowning—intent undetermined Y21

23. Ill-defined non-injuries R00–52,54–94,96–99

Notes

(a) Excluding HIV/AIDS.

(b) Including hepatitis B-related liver cancer and cirrhosis.

(c) Including hepatitis C-related liver cancer and cirrhosis.

(d) Excluding hepatitis B and C related liver cancer.

(e) Including alcoholic cirrhosis.

(f) Excludes those with any other comorbid mental disorders.

(g) Excluding alcoholic and hepatic cirrhosis.

(h) Excluding diabetic-, congenital- and poisoning-related renal failure.

(i) Includes both acute and chronic back pain.

(j) Including renal failure due to dysplasia.

(k) Including polycystic renal failure.

208

Annex Table 2: Principal data sources for epidemiological modelling

Primary data source

Prevalence/

Incidence

Reference

period Disease and injury categories

A. Disease registers, surveillance and notification systems

Incidence 2003 A1 Tuberculosis

Incidence 2003 A2a Syphilis

Incidence 2003 A2b Chlamydia

Incidence 2003 A2c Gonorrhoea

Incidence 2003 A5a Diphtheria

Incidence 2000–03 A5b Pertussis

Incidence 2003 A5c Tetanus

Incidence 2003 A5d Poliomyelitis

Incidence 2003 A5e Measles

Incidence 2003 A5f Rubella

Incidence 2003 A5g Haemophilus influenzae type B

Incidence 1993–96 A5g Hib B sequela

Incidence 2003 A8 Arbovirus infections

Incidence 2003 A9a Hepatitis A

Incidence 2003 A9b Hepatitis B

National Notifiable Diseases Surveillance System:

includes: notifications; and reports: annual report

Communicable diseases intelligence

Incidence 2003 A10 Malaria

HIV/AIDS National Registry Incidence 2003 A3 HIV/AIDS

National Perinatal Data Collection Incidence 2003 D2 Low birthweight

Victorian Perinatal Data Collection Unit Incidence 2001–02 D2 Low birthweight

Queensland Perinatal Data Collection Incidence 2002 D2 Low birthweight

National Cancer Statistics Clearing House Incidence 2001 F Malignant neoplasms

State and territory cancer registries Incidence 1997 F12 Breast cancer

BreastScreen Australia Incidence 2001–02,

1997

F12 Breast cancer

National Diabetes Register Incidence 2001 H Diabetes mellitus

Incidence 2002 H Diabetes Australia and New Zealand Dialysis and mellitus sequela

Transplant Registry Incidence 2002 O1 Nephritis and nephrosis

Victorian Cystic Fibrosis Screening program Incidence 1989–1998 I2 Cystic fibrosis

ABS Causes of death data set Incidence 2003 K5 Motor neurone disease

Incidence 2003 R1 Anencephaly

Western Australian Intellectual Disability

Exploring Answers database Incidence 1983–1996 K9 Intellectual disability

Incidence 2001–02 R2 Spina bifida

Incidence 2001–02 R5 Digestive system malformation

Victorian Perinatal Data Collection Unit Birth

Defects Register

Incidence 2001–02 R6a Renal agenesis

Incidence 2001–02 K9 Intellectual disability

Incidence 1997 R3 Congenital heart disease

Incidence 1997 R5 Digestive system malformation

Incidence 1997 R6b Other urogenital tract

malformations

Congenital malformations, Australia

Incidence 2001 R7 Abdominal wall defect

Western Australian Birth Defects Registry Incidence 2003 R6b

Other urogenital tract

malformations

(continued)

208

Annex Table 2: Principal data sources for epidemiological modelling

Primary data source

Prevalence/

Incidence

Reference

period Disease and injury categories

A. Disease registers, surveillance and notification systems

Incidence 2003 A1 Tuberculosis

Incidence 2003 A2a Syphilis

Incidence 2003 A2b Chlamydia

Incidence 2003 A2c Gonorrhoea

Incidence 2003 A5a Diphtheria

Incidence 2000–03 A5b Pertussis

Incidence 2003 A5c Tetanus

Incidence 2003 A5d Poliomyelitis

Incidence 2003 A5e Measles

Incidence 2003 A5f Rubella

Incidence 2003 A5g Haemophilus influenzae type B

Incidence 1993–96 A5g Hib B sequela

Incidence 2003 A8 Arbovirus infections

Incidence 2003 A9a Hepatitis A

Incidence 2003 A9b Hepatitis B

National Notifiable Diseases Surveillance System:

includes: notifications; and reports: annual report

Communicable diseases intelligence

Incidence 2003 A10 Malaria

HIV/AIDS National Registry Incidence 2003 A3 HIV/AIDS

National Perinatal Data Collection Incidence 2003 D2 Low birthweight

Victorian Perinatal Data Collection Unit Incidence 2001–02 D2 Low birthweight

Queensland Perinatal Data Collection Incidence 2002 D2 Low birthweight

National Cancer Statistics Clearing House Incidence 2001 F Malignant neoplasms

State and territory cancer registries Incidence 1997 F12 Breast cancer

BreastScreen Australia Incidence 2001–02,

1997

F12 Breast cancer

National Diabetes Register Incidence 2001 H Diabetes mellitus

Australia and New Zealand Dialysis and Incidence 2002 H Diabetes mellitus sequela

Transplant Registry Incidence 2002 O1 Nephritis and nephrosis

Victorian Cystic Fibrosis Screening program Incidence 1989–1998 I2 Cystic fibrosis

ABS Causes of death data set Incidence 2003 K5 Motor neurone disease

Incidence 2003 R1 Anencephaly

Western Australian Intellectual Disability

Exploring Answers database Incidence 1983–1996 K9 Intellectual disability

Incidence 2001–02 R2 Spina bifida

Incidence 2001–02 R5 Digestive system malformation

Victorian Perinatal Data Collection Unit Birth

Defects Register

Incidence 2001–02 R6a Renal agenesis

Incidence 2001–02 K9 Intellectual disability

Incidence 1997 R3 Congenital heart disease

Incidence 1997 R5 Digestive system malformation

Incidence 1997 R6b Other urogenital tract

malformations

Congenital malformations, Australia

Incidence 2001 R7 Abdominal wall defect

Western Australian Birth Defects Registry Incidence 2003 R6b

Other urogenital tract

malformations

(continued)

209

Annex Table 2 (continued): Principal data sources for epidemiological modelling

Primary data source

Prevalence/

Incidence

Reference

period Disease and injury categories

B. Health service utilisation data

Incidence 2002–03 A2b Chlamydia sequela

Incidence A2c Gonorrhoea sequela

Incidence A4 Diarrhoea

Incidence A5e Measles sequela

Incidence A6 Meningitis

Incidence A7 Septicaemia

Incidence A8c Dengue fever sequela

Incidence A9a Hepatitis A

Incidence A9c Hepatitis B sequela (D)(a)

Incidence A9c Hepatitis C sequela (D)

Incidence C1 Maternal haemorrhage (P)(b)

Incidence C3 Hypertension in pregnancy (P)

Incidence C4 Obstructed labour (P)

Incidence C5 Abortion (P)

Incidence C6 Other maternal conditions (P)

Incidence D1 Birth trauma & asphyxia

Incidence D3 Neonatal infections

Incidence G Benign neoplasms (P)

Incidence H Diabetes sequela (P)

Incidence I1a Haemolytic anaemia

Prevalence I1b Other non-deficiency anaemia

Incidence K8b Cataract-related blindness (P)

Incidence L2 Ischemic heart disease—AMI

Incidence L3 Stroke

Incidence L7 Aortic aneurysm

Prevalence L8 Peripheral vascular disease (P)

Incidence L8 Peripheral vascular disease

sequela

Prevalence N2 Cirrhosis of the liver (D)

Incidence N3 Appendicitis (P)

Incidence N4 Intestinal obstruction (P)

Incidence N5 Diverticulitis (P)

Incidence N6 Gall bladder and bile duct disease

(P)

Incidence N7 Pancreatitis

Incidence N8 Inflammatory bowel disease (P)

Incidence N9 Vascular insufficiency of intestine

(P)

Incidence O2 Benign prostatic hypertrophy (P)

Incidence Oot Other genitourinary diseases (P)

Incidence Q4 Slipped disc (P)

Incidence R3 Congenital heart disease (P)

Incidence R4 Cleft lip and or palate (P)

Incidence T Unintentional injuries

National Hospital Morbidity Database (diagnoses

or procedures)

Incidence U Intentional injuries

Bettering the Evaluation and Care of Health Incidence 2000–01 B1 Lower respiratory tract infections

Incidence 2000–01 B2 Upper respiratory tract infections

(continued)

210

Annex Table 2 (continued): Principal data sources for epidemiological modelling

Primary data source

Prevalence/

Incidence

Reference

period Disease and injury categories

Incidence 2000–01 B3 Otitis media

Incidence 2003–04 N1 Peptic ulcer disease

Incidence 2003–04 P4 Skin ulcers

Alcohol and Other Drug Treatment Services

National Minimum Data Set Prevalence 2002–03 J1c Stimulant dependence

Incidence 1990–2003 L1 Heart failure

Incidence 1990–2003 L2 Ischemic heart disease

Western Australian Data Linkage System

Incidence 1990–2003 L3 Stroke

Victorian Linked Admitted Episodes Database Incidence 1996–2002 L Heart failure

Incidence 1996–2002 N9 Vascular insufficiency of intestine

C. Population health surveys

2001–02 National Gastroenteritis Survey Incidence 2001–02 A4 Diarrhoea

1980 National Trachoma and Eye Health Program Prevalence 1976–78 A11 Trachoma sequela

Incidence 1976–78 B3 Otitis media

Incidence 1995 B2 Upper respiratory tract infections

Incidence 2001 B3 Otitis media

Prevalence 2001 K10 Migraine

Prevalence 2001 P1 Eczema

Prevalence 2001 Poth Other skin diseases

Prevalence 1995 Q3 Chronic back pain (U)(c)

Incidence 2001 Q7 Gout

Prevalence

& incidence

2001 Qot Other musculoskeletal disorders

National Health Survey

Prevalence

& incidence

1995 Qot Other musculoskeletal disorders

Australian Diabetes, Obesity and Lifestyle Study Incidence 1999–2000 E2 Deficiency anaemia

(AusDiab) Prevalence 1999–2000 H Diabetes mellitus

Risk Factor Prevalence Study, 1989 Incidence 1989 E2 Deficiency anaemia

2002 National non-melanoma skin cancer survey Incidence 2002 F11 Non-melanoma skin cancer

Prevalence 1997 J1a Alcohol dependence

Prevalence 1997 J1c Benzodiazepine dependence

Prevalence 1997 J1d Cannabis dependence

Prevalence 1997 J2 Psychotic disorders

Prevalence 1997 J3 Anxiety and depression

Prevalence 1997 J4 Bipolar disorder

Prevalence 1997 J5 Personality disorders (isolated)

National Mental Health and Wellbeing Survey,

1997—adult component, Low prevalence

(psychotic) disorders component, and child &

adolescent component

Prevalence 1997 J7a ADHD

Australian Child to Adult Development Study Incidence 1990–96 K9 Intellectual disability

Australian Longitudinal Study on Women’s Prevalence 1996–2002 O3 Urinary incontinence

Health(d)

Prevalence 1996–2002 Oot Menstrual problems

Prevalence 1998 O3 Urinary incontinence

Prevalence 2003 Q3 Chronic back pain

Prevalence 2003 Q5 Occupational overuse syndrome

Survey of Disability, Ageing and Carers

Prevalence 1993 Qot Other musculoskeletal disorders

Child Dental Health Survey, Australia Incidence 2000 S1 Dental caries

National Oral Health Survey of Australia Prevalence 1987–88 S1 Dental caries

Prevalence 1987–88 S2 Periodontal disease

South Australian Dental Longitudinal Study Incidence 1991–1996 S1 Dental caries

(continued)

211

Annex Table 2 (continued): Principal data sources for epidemiological modelling

Primary data source

Prevalence/

Incidence

Reference

period Disease and injury categories

The Adelaide Dental Study of Nursing Homes,

one year follow up 1999 Incidence 1999 S1 Dental caries

The Adelaide Dental Study of Nursing Homes

1998 Prevalence 1998 S3 Edentulism

The Longitudinal Study of Dentists’ Practice

Activity Incidence 1998–99 S4 Pulpal infection

Prevalence National Dental Telephone Interview Survey 2002 S3 Edentulism

Incidence 2002 S4 Pulpal infection

D. Epidemiological studies

Incidence A2 STIs (apart from HIV/AIDS)

Incidence A5b Pertussis sequela

Incidence A10 Malaria—sequela

Incidence B3 Otitis media—sequela

Incidence C2 Maternal sepsis—sequela

GBD study

Incidence C3 Hypertensive disorders in

pregnancy—sequela

Incidence A6 Meningitis sequela

Prevalence A9b Hepatitis B

Prevalence A9c Hepatitis C sequela

Incidence D4 Other neonatal causes

Prevalence E2 Deficiency anaemia

Incidence H Diabetes mellitus sequela

Prevalence I3 Haemophilia

Prevalence J1b Heroin dependence

Prevalence J6b Anorexia

Incidence J7b Autism spectrum disorders

Prevalence K4 Multiple sclerosis

Incidence K6 Huntington’s chorea

Incidence K7 Muscular dystrophy

Prevalence K8 Sense organ disorders

Incidence K9 Intellectual disability

Prevalence L3 Stroke

Prevalence M1 Chronic obstructive pulmonary

disease

Prevalence M2 Asthma

Prevalence N2 Cirrhosis of the liver

Prevalence O4 Infertility

Prevalence P1 Eczema

Australian epidemiological studies

Prevalence Poth Other skin diseases

Incidence A2b Chlamydia sequela (i.e. childwish)

Prevalence A9b Hepatitis B sequela

Incidence A9c Hepatitis C sequela

Incidence D1 Birth trauma & asphyxia—sequela

Incidence D2 Low birthweight—sequela

Incidence J6a Bulimia

Incidence K2 Epilepsy

Incidence K10 Migraine

Prevalence M2 Asthma

International epidemiological studies

Incidence N8 Inflammatory bowel disease

(continued)

212

Annex Table 2 (continued): Principal data sources for epidemiological modelling

Primary data source

Prevalence/

Incidence

Reference

period Disease and injury categories

Prevalence O3 Urinary incontinence

Incidence Q1 Rheumatoid arthritis

Incidence Q2 Osteoarthritis

Incidence Q4 Slipped disc

Prevalence Z2 Chronic fatigue syndrome

Meta-analyses of epidemiological studies Prevalence K1 Dementia

Prevalence K3 Parkinson’s disease

E. Estimates that are distributed to other models

Incidence D1 Birth trauma & asphyxia

D2 Low birthweight

D3 Neonatal infections

D4 Other perinatal conditions

R8 Down syndrome

K9 Intellectual disability

R9 Other chromosomal anomalies

Prevalence 1996–2002 L1 Rheumatic heart disease

Incidence 1996–2002 L2 Ischemic heart disease

Incidence 1996–2002 L4 Inflammatory heart disease

Prevalence 1996–2002 L5 Hypertensive heart disease

Incidence 1996–2002 L6 Non-rheumatic valvular disease

L Heart failure

Incidence 1996–2002 M1 Chronic obstructive pulmonary

disease

F. Indirect estimation

A12 Other infectious and parasitic

diseases

D4 Other perinatal conditions

I4 Other endocrine and metabolic

diseases

L9 Other cardiovascular disease

M3 Other chronic respiratory diseases

N10 Other digestive system diseases

R10 Other congenital anomalies

YLL to YLD ratio from rest of category

Oot Other genitourinary diseases

Notes

(a) (D) refers to distributions which are used to estimate incidence to underlying causes.

(b) (P) refers to hospital data on procedures—may or may not be in addition to information on principal diagnosis.

(c) (U) proportion by underlying cause or type of problem (recent versus long-term).

(d) The research on which this report is based was conducted as part of the Australian Longitudinal Study on Women’s Health, The University

of Newcastle and The University of Queensland. We are grateful to the Australian Government Department of Health and Ageing for funding

and to the women who provided the survey data.

213

Annex Table 3: Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

All causes 2,632,770 1,364,614 1,268,156 124,809 102,480 603,937 244,198 289,190 96,727 94,077 514,332 184,705 378,314

I. Communicable diseases,

maternal and neonatal

conditions

123,094 64,993 58,101 24,836 1,807 22,017 6,363 9,970 20,387 3,131 17,027 4,240 13,316

A. Infectious and parasitic

diseases

44,685 27,301 17,385 2,004 901 17,093 4,034 3,269 1,644 1,099 8,662 2,318 3,662

1. Tuberculosis 646 330 316 3 14 150 63 100 4 11 92 44 166

2. Sexually transmitted

diseases(a)

2,048 83 1,966 5 26 40 — 12 54 437 1,412 21 41

a. Syphilis 102 26 77 4 1 8 — 12 36 2 29 — 9

b. Chlamydia 1,188 49 1,139 — 22 26 — — 14 264 830 13 19

c. Gonorrhoea 28 9 19 — 3 6 — — — 5 13 — —

d. Other sexually

transmitted diseases

730 — 730 — — — — — 4 166 539 8 13

3. HIV/AIDS 6,660 5,960 700 7 346 5,417 179 12 6 62 610 22 —

4. Diarrhoeal diseases 1,858 872 986 334 101 309 51 77 348 90 310 63 175

5. Childhood immunisable

diseases

557 315 243 99 7 119 66 23 121 8 47 39 27

a. Diphtheria — — — — — — — — — — — — —

b. Whooping cough 150 70 80 42 7 18 2 1 42 8 26 2 1

c. Tetanus — — — — — — — — — — — — —

d. Poliomyelitis 197 119 78 — — 32 65 22 — — 21 37 21

e. Measles 1 — — — — — — — — — — — —

f. Rubella 25 17 8 17 — — — — 8 — — — —

g. Haemophilus influenzae

type b (Hib)

184 108 76 40 — 68 — — 71 — — — 5

6. Meningitis 2,722 1,405 1,317 937 154 212 74 29 631 234 389 36 27

7. Septicaemia 3,987 2,244 1,743 224 49 719 546 704 144 25 405 231 938

8. Arbovirus infection 1,272 658 614 2 58 544 42 13 8 61 506 25 15

(continued)

214

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

a. Ross River virus 649 307 342 1 26 256 18 5 1 27 292 13 8

b. Barmah Forest virus 253 126 128 — 8 106 8 4 — 9 111 5 2

c. Dengue 5 3 2 — 1 2 — — — — 1 — —

d. Other arbovirus

infection

364 222 142 — 23 180 15 4 6 24 101 6 4

9. Hepatitis 19,889 13,072 6,817 74 36 8,848 2,456 1,659 30 30 3,970 1,305 1,482

a. Hepatitis A 51 26 25 5 3 11 1 7 3 3 8 1 10

b. Hepatitis B(b) 6,961 4,429 2,532 45 31 2,430 967 956 13 16 1,074 530 899

c. Hepatitis C(c) 12,723 8,509 4,214 15 2 6,308 1,488 696 13 12 2,887 775 528

d. Other hepatitis 154 108 46 9 — 98 — — — — — — 46

10. Malaria 89 60 29 30 29 1 — — — — 28 — —

11. Trachoma 121 55 66 — 1 42 11 1 — 1 49 14 2

12. Other infectious and

parasitic diseases

4,835 2,247 2,588 288 80 694 545 640 297 140 843 518 790

B. Acute respiratory

infections

35,502 17,217 18,285 3,388 833 4,461 2,078 6,456 2,790 851 3,791 1,635 9,219

1. Lower respiratory tract

infections

27,354 13,121 14,233 1,067 298 3,360 2,001 6,395 798 268 2,519 1,511 9,137

2. Upper respiratory tract

infections

3,451 1,614 1,837 615 282 618 56 43 615 359 731 82 50

3. Otitis media 4,697 2,482 2,215 1,706 254 484 22 17 1,377 223 541 42 33

C. Maternal conditions 2,152 — 2,152 — — — — — 1 434 1,716 — —

1. Maternal haemorrhage 126 — 126 — — — — — — 19 108 — —

2. Maternal sepsis 332 — 332 — — — — — 1 95 236 — —

3. Hypertensive disorders of

pregnancy

887 — 887 — — — — — 1 204 683 — —

4. Obstructed labour 147 — 147 — — — — — — 24 123 — —

5. Abortion 25 — 25 — — — — — — 12 14 — —

6. Other maternal conditions 634 — 634 — — — — — — 82 552 — —

D. Neonatal causes 34,558 19,027 15,531 19,027 — — — — 15,530 — — — —

1. Birth trauma and asphyxia 9,308 5,086 4,221 5,086 — — — — 4,221 — — — —

(continued)

215

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

2. Low birthweight 15,423 8,281 7,142 8,281 — — — — 7,142 — — — —

3. Neonatal infections 3,404 2,156 1,248 2,156 — — — — 1,248 — — — —

4. Other conditions arising in

the perinatal period

6,424 3,505 2,919 3,505 — — — — 2,919 — — — —

E. Nutritional deficiencies 6,197 1,449 4,748 417 73 462 251 245 421 746 2,858 287 435

1. Protein-energy

malnutrition

97 33 64 1 — 1 — 31 — 1 — 14 48

2. Deficiency anaemia 6,011 1,368 4,643 387 73 461 238 208 421 746 2,842 259 376

3. Other nutritional

deficiencies

89 48 42 30 — — 12 6 1 — 17 14 10

II. Non-communicable

diseases

2,324,625 1,170,116 1,154,509 90,683 72,481 501,687 232,155 273,110 69,322 83,085 472,356 175,985 353,761

F. Malignant neoplasms 499,416 264,382 235,034 2,512 2,530 115,797 77,316 66,226 1,577 1,926 117,559 53,828 60,144

1. Mouth and oropharynx

cancers

13,464 9,483 3,981 36 122 5,902 2,226 1,198 2 53 1,984 910 1,032

2. Oesophagus cancer 14,163 9,983 4,180 — 29 5,044 2,933 1,977 — — 1,292 1,190 1,698

3. Stomach cancer 15,218 9,073 6,145 1 3 4,120 2,788 2,162 — 31 2,661 1,388 2,064

4. Colorectal cancer 63,605 34,643 28,962 2 46 15,622 10,531 8,442 2 52 11,693 7,513 9,703

5. Liver cancer(d) 4,716 3,241 1,474 15 2 1,633 948 643 14 12 648 333 468

6. Gallbladder cancer 3,549 1,429 2,121 — — 601 500 327 — — 752 633 735

7. Pancreas cancer 22,680 11,434 11,246 — — 5,415 3,413 2,606 1 — 4,172 3,023 4,050

8. Lung cancer 88,904 55,028 33,876 62 63 22,112 19,258 13,533 1 30 14,848 9,937 9,059

9. Bone and connective

tissue cancer 5,879 3,317 2,562 315 666 1,536 419 380 212 357 1,388 276 329

10. Melanoma 20,236 13,734 6,501 5 238 8,342 2,836 2,313 2 53 3,450 1,519 1,478

11. Non-melanoma skin

cancers

4,734 3,233 1,502 — 2 1,208 933 1,090 — — 391 246 864

12. Breast cancer 60,654 134 60,520 — — 87 23 24 — 25 41,056 10,445 8,995

13. Cervix cancer 5,231 — 5,231 — — — — — — 24 3,738 741 727

14. Corpus uteri cancer 4,663 — 4,663 — — — — — — — 2,448 1,174 1,041

15. Ovary cancer 11,994 — 11,994 — — — — — 11 164 6,429 2,631 2,758

(continued)

216

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

16. Prostate cancer 36,547 36,547 — — — 9,112 11,950 15,484 — — — — —

17. Testicular cancer 862 862 — 6 123 713 10 11 — — — — —

18. Bladder cancer 10,077 7,010 3,068 1 4 2,046 2,133 2,827 — 28 598 770 1,671

19. Kidney cancer 12,487 7,794 4,694 47 6 4,128 2,092 1,521 53 2 1,618 1,429 1,592

20. Brain cancer 19,792 11,515 8,276 721 515 7,617 1,693 970 543 194 4,959 1,538 1,043

21. Thyroid cancer 1,762 640 1,122 — 14 305 201 120 4 45 675 159 237

22. Lymphoma 22,263 12,375 9,888 173 232 6,212 3,161 2,597 27 318 4,029 2,382 3,132

23. Multiple myeloma 8,925 4,778 4,147 30 — 1,824 1,437 1,487 — 1 1,343 1,216 1,587

24. Leukaemia 19,956 11,393 8,563 785 444 4,841 2,753 2,570 542 342 3,293 1,909 2,477

25. Larynx cancer 3,751 3,263 488 — — 1,644 1,059 560 — — 237 134 117

26. Eye cancer 952 530 422 39 12 279 125 76 38 12 197 67 108

27. Other malignant

neoplasms

22,354 12,945 9,409 276 11 5,455 3,895 3,309 125 181 3,659 2,262 3,183

G. Other neoplasms 10,903 4,615 6,288 155 237 1,377 1,180 1,666 237 45 2,998 1,057 1,951

1. Uterine myomas 1,545 — 1,544 — — — — — — 4 1,447 70 23

2. Benign neoplasms of

meninges and brain

1,451 518 934 42 7 218 98 153 21 6 495 203 209

3. Other benign neoplasms 7,907 4,097 3,810 113 230 1,159 1,082 1,513 215 35 1,056 784 1,719

H. Diabetes mellitus 143,831 77,437 66,394 975 681 48,711 15,183 11,887 911 802 36,213 12,109 16,359

1. Type 1 diabetes 10,891 6,260 4,631 872 548 3,236 980 625 781 404 1,825 592 1,028

2. Type 2 diabetes 132,940 71,176 61,763 103 133 45,476 14,203 11,262 130 398 34,388 11,517 15,330

I. Endocrine and metabolic

disorders

28,565 14,556 14,010 3,395 791 5,470 1,972 2,928 2,162 800 4,600 1,815 4,633

1. Non-deficiency anaemia 5,109 2,739 2,370 917 42 787 399 594 636 36 594 332 773

a. Haemolytic anaemia 1,313 774 539 689 2 14 13 56 476 1 2 14 46

b. Other non-deficiency

anaemia

3,797 1,965 1,832 228 41 773 385 538 160 35 592 318 727

2. Cystic fibrosis 1,863 926 937 520 140 263 — 3 492 244 201 — —

3. Haemophilia 205 169 37 59 — 56 11 43 — — 2 18 16

(continued)

217

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

4. Other endocrine and

metabolic disorders

21,387 10,722 10,665 1,899 608 4,364 1,563 2,288 1,033 520 3,803 1,465 3,844

J. Mental disorders 350,545 165,676 184,869 28,633 48,387 82,282 4,711 1,662 21,492 47,683 112,469 1,878 1,347

1. Substance use disorders 60,782 46,094 14,687 3 14,711 28,148 2,397 836 79 4,180 9,680 417 331

a. Alcohol dependence

and harmful use(e)

34,116 27,225 6,891 — 4,848 19,181 2,378 817 — 416 5,749 395 331

b. Heroin or polydrug

dependence and

harmful use

16,839 12,455 4,383 3 5,657 6,776 14 6 78 2,052 2,233 20 —

c. Benzodiazepine

dependence and

harmful use

2,656 1,102 1,554 — 207 892 3 — — 362 1,189 2 —

d. Cannabis dependence

and harmful use

5,206 4,075 1,131 — 3,520 554 1 — — 983 148 — —

e. Other drug dependence

and harmful use

1,966 1,237 729 — 478 745 — 14 — 367 361 — —

2. Schizophrenia 27,502 14,785 12,717 186 9,795 4,719 25 60 181 3,754 8,639 53 90

3. Anxiety and depression 191,786 65,321 126,464 9,554 17,868 36,126 1,430 343 15,507 29,946 80,515 321 175

4. Bipolar disorder 7,770 3,920 3,849 — 2,672 1,246 2 — — 2,450 1,347 30 23

5. Personality disorders(f) 32,587 16,248 16,339 — 3,130 11,955 816 347 — 2,622 12,044 1,032 642

6. Eating disorders 6,062 375 5,687 103 211 52 — 9 828 4,639 200 — 19

a. Anorexia nervosa 2,933 367 2,567 103 211 52 — — 407 2,063 91 — 5

b. Bulimia nervosa 3,087 — 3,087 — — — — — 421 2,576 90 — —

c. Other eating disorders 41 9 33 — — — — 9 — — 19 — 14

7. Childhood conditions 23,794 18,804 4,990 18,785 — 19 — — 4,896 93 — — —

a. Attention-deficit

hyperactivity disorder

9,928 7,082 2,846 7,082 — — — — 2,840 6 — — —

b. Autism spectrum

disorders

13,866 11,722 2,144 11,703 — 19 — — 2,056 88 — — —

8. Other mental disorders 262 127 135 1 — 17 42 66 — — 43 26 67

(continued)

218

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

K. Nervous system and sense

organ disorders

312,766 146,645 166,121 8,850 7,613 51,886 32,573 45,723 6,744 9,296 45,104 30,004 74,973

1. Dementia 94,399 33,653 60,747 45 42 4,599 7,872 21,095 155 32 3,340 10,236 46,984

2. Epilepsy 14,821 8,479 6,342 3,249 1,209 3,430 353 237 2,446 848 2,248 336 464

3. Parkinson’s disease 26,852 13,664 13,189 — — 3,459 3,958 6,247 — — 2,759 4,979 5,451

4. Multiple sclerosis 5,252 1,609 3,642 18 101 1,345 119 27 79 201 3,112 110 140

5. Motor neurone disease 7,088 3,696 3,392 1 1 1,896 1,124 674 33 — 1,394 1,114 851

6. Huntington’s chorea 1,779 937 842 — 35 758 103 41 — 7 631 124 81

7. Muscular dystrophy 1,046 801 244 221 318 227 35 — 99 29 64 34 18

8. Sense organ disorders 112,728 63,316 49,412 383 1,073 29,229 17,192 15,439 237 857 18,678 11,675 17,964

a. Glaucoma-related

blindness

3,671 1,698 1,974 — — 868 586 244 — — 866 694 414

b. Cataract-related

blindness

2,343 883 1,460 5 2 139 228 510 3 1 153 337 966

c. Macular degeneration 11,642 4,383 7,259 — — 13 1,132 3,238 — — 14 1,338 5,906

d. Adult-onset hearing

loss

64,853 42,653 22,200 — 699 22,983 11,920 7,052 — 432 12,315 5,834 3,618

e. Refractive errors 18,761 8,241 10,520 224 286 2,697 1,941 3,094 90 343 2,861 2,107 5,119

f. Other vision loss 11,457 5,457 5,999 154 87 2,529 1,386 1,301 143 81 2,470 1,364 1,941

9. Migraine 21,848 5,972 15,875 1,523 3,539 910 1 — 955 6,217 8,671 15 17

10. Other nervous system and

sense organ disorders

26,953 14,518 12,435 3,411 1,294 6,034 1,815 1,964 2,741 1,104 4,206 1,381 3,004

L. Cardiovascular disease 473,794 252,405 221,389 2,112 2,414 94,217 59,839 93,822 1,632 1,324 45,697 38,727 134,009

1. Rheumatic heart disease 4,091 1,371 2,720 5 65 585 284 432 33 63 809 702 1,112

2. Ischaemic heart disease 263,497 151,107 112,390 35 322 57,210 37,860 55,680 13 120 20,352 21,052 70,853

3. Stroke 118,462 53,296 65,166 1,436 1,128 17,961 10,938 21,834 984 480 14,237 9,635 39,830

4. Inflammatory heart

disease

15,904 10,134 5,771 419 305 5,207 2,078 2,125 428 156 2,066 1,181 1,939

5. Hypertensive heart

disease

8,982 3,768 5,213 6 5 1,018 885 1,855 7 5 637 708 3,856

(continued)

219

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

6. Non-rheumatic valvular

disease

8,951 4,367 4,584 29 141 1,390 912 1,896 26 80 887 772 2,820

7. Aortic aneurysm 11,338 7,189 4,149 — 59 1,871 2,187 3,071 31 29 580 916 2,594

8. Peripheral vascular

disease

18,606 10,604 8,002 50 74 4,816 2,639 3,026 21 93 2,592 1,519 3,777

9. Other cardiovascular

disease

23,962 10,569 13,394 133 315 4,161 2,058 3,903 90 297 3,537 2,242 7,228

M. Chronic respiratory

disease

186,737 98,925 87,813 23,093 1,936 31,452 17,475 24,968 16,944 6,925 26,552 13,854 23,537

1. Chronic obstructive

pulmonary disease

(COPD)

86,751 49,201 37,550 378 294 21,936 11,693 14,900 174 278 14,923 8,855 13,318

2. Asthma 63,100 29,271 33,828 21,953 1,314 4,802 738 465 16,490 6,641 8,069 1,412 1,216

3. Other chronic respiratory

diseases

36,887 20,453 16,435 762 329 4,715 5,044 9,603 280 5 3,560 3,587 9,003

N. Diseases of the digestive

system

57,957 28,613 29,344 1,204 1,281 14,092 5,083 6,953 799 1,134 11,792 4,535 11,084

1. Peptic ulcer disease 6,358 3,292 3,065 32 39 1,622 662 937 — 6 1,148 334 1,577

2. Cirrhosis of the liver(g) 1,524 687 838 31 17 277 112 249 1 3 178 87 569

3. Appendicitis 648 324 323 53 59 135 13 64 41 60 154 30 38

4. Intestinal obstruction 5,019 2,227 2,792 61 18 665 582 902 10 18 927 381 1,455

5. Diverticulitis 6,118 2,829 3,289 — 6 1,373 701 749 — 1 1,072 921 1,296

6. Gallbladder and bile duct

disease 3,202 1,212 1,990 2 6 395 359 450 3 55 852 295 785

7. Pancreatitis 2,501 1,464 1,037 2 38 921 232 273 2 37 498 151 348

8. Inflammatory bowel

disease

12,176 6,334 5,843 553 1,001 4,369 264 148 523 854 4,044 227 195

9. Vascular insufficiency of

bowel

3,982 1,647 2,335 125 29 463 365 664 32 35 557 592 1,119

10. Other digestive system

diseases

16,430 8,597 7,832 346 69 3,872 1,792 2,518 186 64 2,362 1,518 3,702

(continued)

220

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

O. Genitourinary diseases 65,249 28,163 37,086 127 1,637 11,461 5,791 9,148 1,068 7,860 14,951 3,273 9,935

1. Nephritis and nephrosis(h) 21,133 10,688 10,444 106 107 2,808 1,933 5,734 46 146 1,944 1,632 6,677

2. Benign prostatic

hypertrophy

7,622 7,622 — — — 2,723 2,950 1,949 — — — — —

3. Urinary incontinence 8,263 1,823 6,440 — — 898 542 383 1 217 4,271 1,053 898

4. Infertility 14,344 6,268 8,076 21 1,502 4,746 — — 19 1,822 6,236 — —

5. Other genitourinary

diseases

13,888 1,762 12,126 — 28 286 365 1,082 1,002 5,676 2,500 589 2,360

P. Skin diseases 20,302 9,852 10,451 1,446 1,679 4,555 1,126 1,045 1,593 1,778 2,672 1,408 3,000

1. Eczema 2,730 1,031 1,699 371 47 555 31 27 1,210 42 413 31 2

2. Acne 3,899 1,988 1,910 646 1,013 329 — — 242 1,198 470 — —

3. Psoriasis 4,021 3,122 899 206 578 2,059 174 105 58 192 524 76 49

4. Ulcers 9,324 3,620 5,704 222 41 1,575 886 895 82 346 1,177 1,235 2,864

5. Other skin diseases 329 90 238 1 — 37 35 18 — — 88 65 84

Q. Musculoskeletal diseases 105,508 44,210 61,298 856 1,289 27,639 8,375 6,052 1,305 1,639 35,570 11,574 11,211

1. Rheumatoid arthritis 16,841 4,780 12,062 343 214 2,833 888 502 958 513 7,658 1,710 1,222

2. Osteoarthritis 34,578 14,495 20,083 1 58 7,772 3,863 2,802 — — 7,356 6,088 6,638

3. Back pain(i) 29,658 14,470 15,188 275 541 9,776 2,227 1,650 206 610 10,704 2,012 1,657

4. Slipped disc 6,120 3,439 2,681 13 144 2,711 386 184 29 84 1,956 401 211

5. Occupational overuse

syndrome 4,953 697 4,256 — 9 663 24 — — 65 4,177 13 1

6. Systemic lupus

erythematosus (SLE) 1,609 168 1,441 — 1 43 56 68 1 76 984 186 193

7. Gout 1,988 1,636 352 2 85 1,330 100 119 1 59 131 97 64

8. Other musculoskeletal

diseases 9,759 4,525 5,235 222 236 2,511 829 726 109 232 2,605 1,066 1,223

R. Congenital anomalies 33,228 18,770 14,458 14,738 624 2,688 345 374 10,838 528 2,172 439 481

1. Anencephaly 387 102 285 102 — — — — 285 — — — —

2. Spina bifida 812 408 404 307 31 57 12 — 270 30 105 — —

3. Congenital heart disease 8,394 4,975 3,419 3,434 282 1,091 97 71 2,202 268 723 135 90

(continued)

221

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

4. Cleft lip and/or palate 221 112 109 112 — — — — 109 — — — —

5. Digestive system

malformations 493 244 248 207 — 16 12 8 222 1 — 12 14

a. Anorectal atresia 31 17 14 17 — — — — 14 — — — —

b. Oesophageal atresia 31 19 12 19 — — — — 12 — — — —

c. Other digestive system

malformations 431 208 223 171 — 16 12 8 196 1 — 12 14

6. Urogenital tract

malformations 2,575 1,560 1,016 568 1 547 168 276 144 — 393 191 288

a. Renal agenesis(j) 279 153 126 145 1 7 — — 82 — 29 11 3

b. Other urogenital tract

malformations(k) 2,296 1,407 890 422 — 540 168 276 62 — 364 180 284

7. Abdominal wall defect 312 210 102 210 — — — — 102 — — — —

8. Down syndrome 3,808 2,181 1,627 1,668 61 429 22 — 1,059 2 470 79 18

9. Other chromosomal

disorders 8,493 4,685 3,807 4,682 1 2 — — 3,754 1 52 — —

10. Other congenital

anomalies 7,733 4,293 3,440 3,448 248 546 32 19 2,692 226 429 21 71

S. Oral conditions 24,507 11,402 13,105 1,114 1,098 7,359 1,186 645 1,062 1,065 8,490 1,470 1,017

1. Dental caries 12,088 6,026 6,061 665 789 3,860 427 285 631 760 3,819 375 476

2. Periodontal disease 581 280 301 5 20 230 19 7 5 19 237 30 9

3. Edentulism 5,264 1,880 3,384 2 7 1,166 526 179 3 12 2,281 836 252

4. Pulpitis 6,497 3,197 3,300 443 283 2,103 214 155 424 274 2,127 228 248

5. Other oral conditions 77 18 59 — — — — 18 — — 26 — 32

Z. Ill-defined conditions 11,317 4,467 6,850 1,470 283 2,701 — 13 958 280 5,517 14 81

1. Sudden infant death

syndrome 2,428 1,470 958 1,470 — — — — 958 — — — —

2. Chronic fatigue syndrome 8,890 2,997 5,893 — 283 2,701 — 13 — 280 5,517 14 81

(continued)

222

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

III. Injuries 185,050 129,504 55,546 9,290 28,191 80,233 5,681 6,109 7,018 7,861 24,949 4,480 11,238

T. Unintentional injuries 125,862 84,201 41,661 8,695 19,148 46,795 4,154 5,408 6,293 5,662 14,745 3,963 10,997

1. Road traffic accidents 42,425 31,028 11,397 1,991 10,380 17,215 838 605 1,336 3,572 5,253 621 616

2. Other transport accidents 8,601 6,782 1,819 779 1,756 3,996 177 74 556 316 815 62 70

3. Poisoning 12,046 6,922 5,124 54 927 5,501 230 210 55 463 2,722 691 1,194

4. Falls 26,386 13,118 13,269 1,552 1,717 5,171 1,490 3,188 1,086 379 2,119 1,870 7,814

5. Fires, burns and scalds 4,399 2,822 1,577 786 279 1,499 154 103 564 63 775 67 108

6. Drowning 4,812 3,366 1,447 646 672 1,854 114 79 706 94 532 81 34

7. Sports injuries 579 344 234 71 112 147 8 6 44 44 96 16 35

8. Natural and environmental

factors 1,927 1,330 597 163 277 780 53 57 190 98 182 54 72

9. Machinery accidents 5,095 4,725 370 214 957 3,255 227 71 37 47 270 11 4

10. Other unintentional

injuries(l) 19,591 13,765 5,827 2,440 2,070 7,378 862 1,015 1,718 586 1,981 491 1,050

Suffocation and foreign

bodies 5,727 3,930 1,797 736 606 2,133 172 283 734 181 529 55 298

Adverse effects of

medical treatment 3,695 2,016 1,678 96 124 812 405 581 55 127 580 347 570

Other unintentional

injuries n.e.c. 10,169 7,818 2,351 1,608 1,340 4,433 285 152 929 278 872 89 182

U. Intentional injuries 59,189 45,303 13,886 594 9,043 33,438 1,527 701 726 2,199 10,204 517 240

1. Suicide and self-inflicted

injuries 49,916 38,717 11,199 176 7,320 29,099 1,437 685 208 1,479 8,854 467 191

2. Homicide and violence 9,221 6,535 2,686 418 1,722 4,289 90 16 518 721 1,349 50 49

3. Legal intervention and war 51 51 — — 1 50 — — — — — — —

Australian population (‘000) 19,881 9,872 10,010 2,041 1,404 5,292 656 478 1,938 1,349 5,311 694 718

DALYs per 1,000 population 132.4 138.2 126.7 61.2 73.0 114.1 372.3 605.0 49.9 69.7 96.8 266.1 526.9

(continued)

223

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

Risk factors

Alcohol 61,091 52,180 8,911 737 11,648 38,139 2,867 –1,211 237 1,518 10,704 –296 –3,252

Illicit drugs 51,463 36,515 14,948 78 11,892 21,161 2,109 1,276 67 4,246 8,579 1,067 989

Tobacco 204,788 131,616 73,172 2,238 88 62,414 35,879 30,997 1,757 22 28,699 18,915 23,780

Unsafe sex 14,897 6,217 8,679 22 303 5,022 514 357 60 493 5,990 1,004 1,132

Child sexual abuse 23,513 4,166 19,348 — 704 3,204 173 84 — 4,309 14,597 209 232

Intimate partner violence 29,360 — 29,360 — — — — — — 5,455 22,325 901 678

Occupational exposures &

hazards 51,362 35,492 15,870 — 2,853 25,291 4,245 3,104 — 1,387 12,458 1,097 928

Physical inactivity 174,431 87,742 86,689 — 147 42,424 21,262 23,909 — 166 32,596 17,172 36,756

High blood pressure 199,315 107,098 92,218 — — 33,296 28,717 45,085 — — 12,100 18,236 61,882

High body mass 197,632 105,616 92,017 — — 65,684 22,683 17,248 — — 46,520 20,534 24,963

Low fruit and vegetable

consumption

55,259 36,429 18,830 — 103 18,804 9,111 8,411 — 38 6,272 4,150 8,370

High blood cholesterol 163,591 89,669 73,922 — — 45,316 19,718 24,635 — — 17,979 14,247 41,695

Osteoporosis 4,386 1,019 3,368 — — 18 128 873 — — 23 209 3,135

Air pollution - short term 7,781 4,032 3,750 70 37 981 1,010 1,935 54 8 629 702 2,356

Particulates 3,807 1,976 1,831 19 11 590 470 885 12 4 274 323 1,219

Ozone 3,974 2,056 1,918 50 25 391 539 1,050 42 4 355 379 1,138

Air pollution - long term 19,738 10,422 9,316 — — 4,097 2,768 3,557 — — 2,280 1,740 5,296

Joint effect of all risk factors 847,307 478,511 368,796 3,075 27,569 242,892 99,049 105,926 2,122 15,726 155,198 63,319 132,432

Alternative burden of disease categories

Diabetes mellitus

(attributable) 218,518 112,615 105,904 977 688 56,122 24,190 30,637 913 805 39,282 17,720 47,183

Anxiety and depression

(attributable) 215,783 80,770 135,013 9,560 19,056 48,235 2,620 1,298 15,526 30,441 86,556 1,134 1,356

All intellectual disability 44,187 22,822 21,365 18,743 666 3,043 228 141 18,591 270 1,935 244 326

All vision loss 55,539 26,828 28,711 5,354 404 6,746 5,548 8,775 384 425 6,834 6,109 14,959

All nephritis and nephrosis 68,721 37,691 31,030 519 1,029 15,723 8,514 11,905 215 682 8,480 6,281 15,371

(continued)

224

Annex Table 3 (continued): Disability-adjusted life years (DALYs) by age, sex and cause, Australia, 2003

Notes

(a) Excludes HIV/AIDS.

(b) Includes hepatitis B-related liver cancer and cirrhosis.

(c) Includes hepatitis C-related liver cancer and cirrhosis.

(d) Excludes liver cancer related to hepatitis B and C.

(e) Includes alcoholic cirrhosis.

(f) Excludes those with any other comorbid mental disorders.

(g) Excludes alcoholic and hepatic cirrhosis.

(h) Excludes diabetic-, congenital- and poisoning-related renal failure.

(i) Includes both acute and chronic back pain.

(j) Includes renal failure due to dysplasia.

(k) Includes polycystic renal failure.

(l) Includes suffocation and foreign bodies, adverse effects of medical treatment,

other mechanical force injuries and other unintentional injuries.

225

Annex Table 4: Deaths by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

All causes 132,287 68,325 63,962 1,004 1,071 15,483 14,039 36,728 776 399 8,895 8,295 45,597

I. Communicable diseases,

maternal and neonatal

conditions

6,847 3,464 3,383 405 15 734 496 1,813 314 14 340 267 2,449

A. Infectious and parasitic

diseases 2,416 1,465 952 28 10 606 319 501 23 10 254 150 514

1. Tuberculosis 52 26 26 — — 5 5 16 — — 2 3 21

2. Sexually transmitted diseases(a) 12 2 10 — — — — 2 1 — 4 — 5

a. Syphilis 5 2 3 — — — — 2 1 — 1 — 1

b. Chlamydia 4 — 4 — — — — — — — 2 — 2

c. Gonorrhoea — — — — — — — — — — — — —

d. Other sexually transmitted

diseases 3 — 3 — — — — — — — 1 — 2

3. HIV/AIDS 119 108 11 — — 94 12 1 — — 10 1 —

4. Diarrhoeal diseases 48 18 29 — 1 3 3 11 1 — — 3 25

5. Childhood immunisable

diseases

27 16 11 1 — 5 6 4 2 — 1 3 5

a. Diphtheria — — — — — — — — — — — — —

b. Whooping cough — — — — — — — — — — — — —

c. Tetanus — — — — — — — — — — — — —

d. Poliomyelitis 20 12 8 — — 2 6 4 — — 1 3 4

e. Measles — — — — — — — — — — — — —

f. Rubella — — — — — — — — — — — — —

g. Haemophilus influenzae

type b (Hib) 7 4 3 1 — 3 — — 2 — — — 1

6. Meningitis 61 29 32 11 4 5 5 4 9 6 12 2 3

7. Septicaemia 304 156 149 5 1 23 35 91 3 — 9 11 125

8. Arbovirus infection — — — — — — — — — — — — —

a. Ross River virus — — — — — — — — — — — — —

(continued)

226

Annex Table 4 (continued): Deaths by age, sex and cause, Australia, 2003

Males Females

Cause Persons Males Females 0–14 15–24 25–64 65–74 75+ 0–14 15–24 25–64 65–74 75+

b. Barmah Forest virus — — — — — — — — — — — — —

c. Dengue — — — — — — — — — — — — —

d. Other arbovirus infection — — — — — — — — — — — — —

9. Hepatitis 1,455 933 521 2 1 439 212 280 1 1 187 100 233

a. Hepatitis A 2 1 1 — — — — 1 — — — — 1

b. Hepatitis B(b) 625 381 244 1 1 121 83 175 — — 49 41 154

c. Hepatitis C(c) 824 550 274 — — 317 129 104 — — 138 59 76

d. Other hepatitis 3 1 2 — — 1 — — — — — — 2

10. Malaria 3 2 1 1 1 — — — — — 1 — —

11. Trachoma — — — — — — — — — — — — —

12. Other infectious and parasitic

diseases

335 174 161 8 2 30 41 92 6 3 28 27 97

B. Acute respiratory infections 3,724 1,630 2,095 23 5 128 176 1,297 19 1 78 110 1,886

1. Lower respiratory tract

infections 3,709 1,624 2,085 21 5 126 176 1,295 18 1 76 110 1,880

2. Upper respiratory tract

infections 9 3 6 — — 1 — 2 1 — 1 — 4

3. Otitis media 6 3 3 2 — 1 — — — — 1 — 2

C. Maternal conditions 9 — 9 — — — — — — 2 7 — —

1. Maternal haemorrhage 1 — 1 — — — — — — — 1 —