Leading underlying causes of death
Analysis of causes of death is useful for understanding the health of a population. The underlying cause of death identifies where there could have been intervention to stop the death from happening.
In 2024, the 10 leading causes of death make up just under half of all causes of death (Table S3.1). This highlights the importance of this type of analysis.
Understanding what people die from, particularly over time or between different groups, helps us to understand:
- service needs
- emerging health trends
- if programs and policy are working
- which population groups may need additional support.
Changes in the pattern of causes of death can be impacted by individual or more broader factors, such as:
Individual factors
Health behaviours (i.e. cancer screening, physical activity, healthy diet); Health-harming behaviours (i.e. smoking, illicit substance use); Exposure to disease/injury; Genetics
Broader factors
Socio-economic area; Physical environment; Administrative changes; Mortality coding practices
Leading underlying causes of death are determined by grouping specific causes of death and counting the number of deaths assigned to each cause group. Over 14,000 specific causes of illness, injury and death are presented in the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10). These causes can be grouped in a way that is meaningful for public health purposes.
A common grouping is by ICD chapters which are broad categories arranged according to the type of disease, the body system affected by the disease or the circumstances causing death. Each chapter is further divided into blocks of related diseases. Australian cause of death data by ICD-10 chapters and selected causes of death are published in the AIHW General Record of Incidence of Mortality (GRIM) books.
For leading underlying cause of death analysis, information needs to be more specific than ICD chapters and blocks. There is no standard method for grouping causes, however, the AIHW follows the recommendations of the World Health Organization (WHO) (Becker et al. 2006) with minor modifications to suit the Australian context. This grouping is a mix of ICD chapters, blocks and specific diseases to maximise information, separate out ill-defined causes and highlight health priority areas.
The leading underlying causes of death presented here are classified using an AIHW-modified version of Becker et al (2006).
Change in leading cause of death
In 2024, dementia including Alzheimer’s disease (dementia) overtook coronary heart disease as the leading cause of death. While dementia is the leading cause overall, just over 1,200 deaths separate the two causes.
Considering the leading causes by sex (Figure 3.1):
- coronary heart disease remains the leading cause of death for males
- dementia is the leading cause of death for females
- both males and females have leading causes due to lung, colorectal, and sex-specific cancers
- suicide is a leading cause of death for males, but not females.
Figure 3.1: Leading underlying causes of death in Australia, by sex, 2024
The leading causes of death in 2024 were coronary heart disease for men and dementia for women. Other leading causes included lung cancer, cerebrovascular disease and COPD.
Leading underlying causes of death by age
As well as differences by sex, the leading causes of death also vary by age (Figure 3.2). Generally, younger people are more likely to die from childhood-related conditions and external causes. As people age, chronic conditions become leading underlying causes of death.
In 2024:
- 4 in 5 deaths of infants were due to perinatal and congenital conditions
- land transport accidents were the most common cause of death overall for people aged 1–14
- more than 1 in 4 people aged 15–24 and 1 in 5 people aged 25–44 died by suicide.
Cancer is a leading cause of death at younger ages for females compared with males. In 2024:
- 1 in 14 deaths of females aged 25–44 were due to breast cancer
- 1 in 25 deaths of females aged 25–44 were due to colorectal cancer
- breast and lung cancer were the two leading causes of death for females aged 45–64
- lung cancer was the second leading cause of death for males aged 45–74.
Chronic diseases feature more prominently among people aged 45 and over:
- coronary heart disease was the leading cause of death for males aged 45–84
- chronic obstructive pulmonary disease (COPD) is a leading cause of death for females aged 45–84
- dementia including Alzheimer’s disease is the leading cause of death for females aged over 75 and males aged over 85.
Figure 3.2: Leading underlying causes of death in Australia, by age group, 2024
Tile chart shows the leading underlying causes of death for people aged 1-44 years are external causes. Middle to older ages have more chronic disease as leading underlying causes of death.
COPD = Chronic obstructive pulmonary disease.
Notes
- ‘Other ill-defined causes’ include the following codes: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (ICD-10 codes R00–R99, excluding R95: Sudden infant death syndrome (SIDS)); Respiratory failure of newborn (P28.5); Respiratory failure, unspecified (J96.9). AIHW General Record of Incidence of Mortality (GRIM) books are available for selected leading causes of death.
- Heart failure refers to ‘Heart failure and complications and ill-defined heart disease (I50–I51)’.
- The number of deaths due to suicide should be considered preliminary and typically increase across revisions cycles, as more information becomes available in the coronial process. For information on coding practices, interpretation of suicide data, and revisions process refer to Deaths due to intentional self-harm (suicide) and Data quality: Revisions process in the Methodology of Causes of Death, Australia, ABS.