Burden of disease

The Australian Burden of Disease Study undertaken by the AIHW provides information on the burden of disease for the Australian and Aboriginal and Torres Strait Islander populations. The study builds on the AIHW's previous burden of disease studies and disease monitoring work and provides Australian-specific estimates for more than 200 diseases and injuries, grouped into 17 disease groups. It also provides estimates of how much of the burden can be attributed to various risk factor exposures, such as tobacco use and overweight (including obesity).

The summary measure of burden of disease analysis is the DALY. One DALY is one year of 'healthy life' lost due to illness and/or death. The more DALY associated with a disease or injury, the greater the burden. DALY are estimated for every occurrence of every disease and then added together for the whole population, to indicate the total disease burden. The DALY is produced by combining the non-fatal and fatal burden together. People generally experience more burden as they age.

Non-fatal burden is expressed as years lived with disability (YLD). YLD measures the proportion of healthy life lost due to living with a disease in a given year, and is influenced by the number of people with each disease, how long they spend living with it and how severe the effects are.

Fatal burden, expressed as years of life lost (YLL), measures years lost between the age at which a person dies and the number of years they could have potentially gone on to live, based on the current best life expectancy across the world.

The attributable burden is the amount of burden that could be avoided if the risk factor were removed. The risk factors analysed in the study were selected because they are modifiable, with strong evidence that they are linked to diseases that occur in Australia. While it is an extensive list, it does not cover all potential risk factors.

Information on the health impacts and distribution of different diseases, injuries and risk factors is important for monitoring population health and providing an evidence base to inform health policy and service planning. Burden of disease information can also be used to measure the health impact of interventions, and to highlight which diseases or risk factors to focus on when investigating the cost-effectiveness of programs and interventions.