6 October, 2025
dementia-overtakes-heart-disease-as-leading-cause-of-death-in-australia

Dementia, a condition characterized by declines in memory, language, and cognitive function, has now become the leading cause of death in Australia, surpassing heart disease. This shift, reported earlier this month by the Australian Institute of Health and Welfare, reveals that in 2023, dementia was responsible for 17,400 deaths, accounting for 9.5% of all fatalities in the country.

The report also indicates that dementia can be an associated factor in an additional 15,000 deaths, categorized as dying with dementia. These figures suggest that the true impact of dementia may be even greater, as under-reporting on death certificates is common.

Understanding Dementia’s Progression and Impact

Dementia is primarily a neurodegenerative condition, with Alzheimer’s disease being the most prevalent form, making up 60-70% of cases. The disease leads to a progressive loss of brain cells, affecting essential functions such as memory, communication, and reasoning. As the condition advances, it affects vital areas of the brain responsible for functions like breathing and swallowing, which can lead to death either directly or through complications.

Secondary Complications and Their Fatal Consequences

In the later stages of dementia, swallowing difficulties can lead to severe complications. Patients may inhale food or liquids into their lungs, resulting in bacterial infections like aspiration pneumonia. A 2019 review of 19 studies found that individuals with dementia have double the risk of dying from pneumonia compared to those without the condition.

Pneumonia accounted for more than 29.69% of deaths among dementia patients, and when confirmed via autopsy, this figure rose to nearly 50%.

Other complications include dehydration, weight loss, and malnutrition, exacerbated by a loss of appetite. These issues weaken the immune system, making it harder for patients to fight infections. Urinary tract infections, often undetected due to communication challenges, can lead to sepsis, a severe and potentially fatal response to infection.

The Role of Age and Other Health Conditions

Age is a significant risk factor for dementia. While only one in 1,000 Australians aged 30-59 have dementia, this number jumps to 210 in 1,000 among those aged 85-89. Older individuals often face additional health issues such as heart disease, diabetes, and high blood pressure, which can complicate dementia care.

When dementia contributes to but does not directly cause death, it is often recorded as dying with dementia. In such cases, other conditions like heart disease, stroke, and diabetes may be the primary causes of death.

Preventing Dementia: Modifiable Risk Factors

Despite its prevalence, dementia is not an inevitable part of aging. The Lancet Commission on dementia has identified 14 modifiable risk factors that could potentially prevent up to 45% of dementia cases. These include:

  • Less education
  • Hearing loss
  • High low-density lipoprotein (LDL) cholesterol
  • Depression
  • Traumatic brain injury
  • Physical inactivity
  • Diabetes
  • Smoking
  • High blood pressure (hypertension)
  • Obesity
  • Excessive alcohol consumption
  • Social isolation
  • Exposure to air pollution
  • Vision loss

Addressing these factors at both individual and policy levels could significantly reduce the incidence of dementia, allowing people to live longer and healthier lives.

As dementia continues to impact more lives, understanding its complexities and working towards prevention becomes crucial. With a growing aging population, the need for effective strategies to combat dementia and its effects is more pressing than ever.

This article first appeared on The Conversation, with insights from Lyndsey Collins-Praino, an associate professor at the University of Adelaide School of Biomedicine.