Burden of disease is an indication of the impact of living with illness and injury and dying prematurely. It is measured using disability-adjusted life years (DALY), which is the number of years of healthy life lost due to death and illness. See also 'A note on DALYs' below.
Leading causes of disease, injury and death
In Australia, most of the total burden of disease in 2015 was from chronic diseases and injury (Australian Institute of Health and Welfare 2019).
Figure 1 shows the proportion of total burden by disease group in Australia in 2015.
In 2015, 50.4 per cent of the burden was due to living with illness and 49.6 per cent was due to dying prematurely. This is the first time that the burden from living with illness has surpassed the fatal burden.
Chronic diseases and injuries made up most of the burden, with 65 per cent of it coming from the top five categories of cancer, cardiovascular diseases, musculoskeletal conditions, mental and substance use disorders and injuries.
In terms of specific diseases, the five leading causes of the total burden in Victoria in 2015 were coronary heart disease (heart attack or angina), back pain and back problems, dementia, chronic obstructive pulmonary disease (lung diseases) and anxiety disorders.
Some population groups face a greater burden than others
There is considerable variation in deaths and years of life lost across population groups.
People in remote areas face a burden 1.4 times higher than those in major cities.
People in low socioeconomic groups face a burden 1.5 times higher than the rate of the highest socioeconomic groups.
In 2011, Aboriginal Australians experienced twice the rate of disease burden compared with non-Aboriginal Australians.
Modifiable risk factors
A large proportion of disease burden could be prevented.
Thirty-eight per cent of the total burden of disease experienced by Australians in 2015 could have been prevented by reducing exposure to lifestyle risk factors such as:
- tobacco use
- overweight and obesity
- poor diet
- physical inactivity
- alcohol use
- high blood pressure (Australian Institute of Health and Welfare 2019).
The five risk factors that caused the most burden in 2015 were tobacco use (responsible for 9.3 per cent of total burden), overweight and obesity (8.4 per cent), dietary risks (7.3 per cent), high blood pressure (5.8 per cent) and high blood plasma glucose including diabetes (4.7 per cent). These are summarised in the table below with their impact on selected disease groups.
Table: Proportion of total burden (DALY) attributable to the leading risk factors, for selected disease groups, 2015
Source: Australian Institute of Health and Welfare 2019
Notes: Estimates for diet are based on an analysis of the joint effects of all dietary risk factors included in the study following methods used in recent global burden of disease studies. Blank cells indicate the risk factor has no associated diseases or injuries in the disease group.
Trends in risk factors in Victoria
Smoking is still the single greatest contributor to the disease burden in Australia, responsible for 9.3 per cent of the disease burden in Australia.
However, when all dietary factors are considered together – overweight and obesity, dietary risks and high blood plasma glucose – their combined proportion of the total disease burden is 20.4, compared with smoking’s contribution of 9.3 per cent. This shows how important it is to address diet-related factors when discussing efforts to reduce the disease burden in Australia.
Smoking is responsible for 9.3 per cent of the disease burden in Australia, and also contributes 22 per cent to the cancer burden and 41 per cent to the respiratory burden.
The overall smoking rate is declining, with 12.3 per cent of Victorian adults identified as daily smokers in 2016.
However, the rate of decrease has slowed, and rates remain high among certain groups.
Visit the Chief Health Officer's report Tobacco-free living page for more information.
Overweight and obesity
Overweight and obesity has become the second leading cause of the disease burden, responsible for 8.4 per cent of the total burden and 19.3 per cent of the cardiovascular burden.
Victoria (and Australia) has one of the highest rates of overweight and obesity in the world. Nearly a third of Victorian adults – 31.5 per cent or 1.5 million people – are obese. Another third are overweight, meaning two-thirds of the adult population are overweight or obese – around 2.3 million Victorians.
More than one in five children aged two to 17 years is overweight or obese (Australian Bureau of Statistics 2018).
Overweight and obesity are also linked to the high blood plasma glucose burden.
Visit the Chief Health Officer's report Overweight and obesity page for more information.
High blood plasma glucose burden
The rate of type 2 diabetes has been steadily rising in recent decades, particularly among older people.
In 2016, 5.9 per cent of Victorians reported having the condition.
Visit the Chief Health Officer's Overweight and obesity page and the Chief Health Officer's Healthy eating page for more information.
Dietary factors account for 7.3 per cent of the total burden of disease in Australia.
Only one in 20 adults in Victoria meets the recommended guidelines for vegetables, which is five to six serves per day (Department of Health and Human Services 2018).
Adults on average eat less than half the recommended amount of vegetables.
Around 40 per cent of adults meet the guidelines for fruit, which is two serves per day.
Visit the Chief Health Officer's Healthy eating page for more information.
Physical inactivity accounted for 2.5 per cent of the disease burden in Australia.
These estimates reflect the amount of disease burden that could have been avoided if all people in Australia were sufficiently physically active.
Half of adults in Victoria do not undertake the recommended amount of physical activity per week, and three-quarters of adolescents do not do the one hour of exercise recommended for their age group (Department of Health and Human Services 2018). Lifestyles are also becoming increasingly sedentary.
A quarter of adults spend seven hours or more a day sitting, while two-thirds of adolescents spend two hours or more per day on electronic devices (Department of Education and Training 2017).
Visit the Chief Health Officer's Active living page for more information.
Preventing or modifying risk factors
The good news is that many of these risk factors can be prevented or modified.
You can work towards quitting smoking, reducing alcohol intake, exercising more and eating more fruit and vegetables if these are relevant for you.
However, according to the social determinants of health framework, some groups in society have greater access to the resources needed to address these risk factors than others.
Visit the Chief Health Officer's Social determinants of health page for more information.
A note on DALYs
Disability-adjusted life years (DALYs) is a summary measure of disease burden.
One DALY is one year of healthy life lost due to illness and/or premature death – the higher the metric, the greater the burden of that disease (Australian Institute of Health and Welfare 2019).
The proportion of total burden attributable to each risk factor is listed in the table above.
For example, more than 9 per cent of the disease burden for Australians in 2015 was due to tobacco use.
Australian Bureau of Statistics 2018. National health survey: first results, 2017–18, Australian Bureau of Statistics, Canberra.
Australian Institute of Health and Welfare 2017, Impact of overweight and obesity as a risk factor for chronic conditions, Australian Burden of Disease study series, no. 11, Australian Institute of Health and Welfare, Canberra.
Australian Institute of Health and Welfare 2018a, Australia's health 2018, Australian Institute of Health and Welfare, Canberra.
Australian Institute of Health and Welfare 2018b. Risk factors and disease burden, Australian Institute of Health and Welfare, Canberra.
Australian Institute of Health and Welfare 2019, Australian burden of disease study: impact and causes of illness and death in Australia 2015, Australian Institute of Health and Welfare, Canberra.
Department of Education and Training 2017, About You: Victorian student health and wellbeing survey 2016, State Government of Victoria, Melbourne.
Department of Health and Human Services 2018, The Victorian Population Health Survey 2016, State Government of Victoria, Melbourne