Prevalence of dementia

Key statistics 

The exact number of people with dementia in Australia is currently not known. However, it is estimated that in 2021 there are between 386,200 (estimated by AIHW) and 472,000 Australians with dementia (Dementia Australia 2020). These estimates vary because there is no single authoritative data source for deriving dementia prevalence in Australia, and different approaches are used to generate estimates.

This page presents dementia prevalence, as estimated by AIHW:

It also presents how the prevalence rate of dementia in Australia compares with other countries

Expand the headings below for information on the available data sources and methodologies to estimate dementia prevalence. Refer to the Prevalence data tables for the underlying data presented in this page.

See Population health impacts of dementia among Indigenous Australians and Dementia among people from culturally and linguistically diverse backgrounds for more information on the challenges involved in estimating dementia prevalence among these groups.

How many people have dementia in Australia?

The AIHW estimates for 2021 indicate that there are around 386,200 people living with dementia in Australia, including 243,200 women and 143,000 men. This is equivalent to 15 people with dementia per 1,000 Australians (18 per 1,000 women and 11 per 1,000 men).

The rate of dementia rises quickly with age—from less than 1 person with dementia per 1,000 Australians aged under 60, to 68 per 1,000 Australians aged 75–79, and then to 399 per 1,000 Australians aged 90 and over. Interestingly, the rates are similar for men and women in the younger age groups, but quickly diverge with increasing age. For the oldest age group, the rate of dementia among women is 1.4 times the rate of men (479 per 1,000 women and 337 per 1,000 men) (Figure 2.1).

Figure 2.1: Prevalence of dementia in 2021: estimated number and rate, by age and sex 

Figure 2.1 is a bar graph showing the estimated number and rate of men, women and persons with dementia in Australia by age in 2021. It shows that the number and rate of men, women and persons with dementia increases with age. The rate of dementia is higher in women than men in each age group, with the difference greatest among those aged 90 and over.

65% of people with dementia live in the community

Based on the AIHW estimates, there are an estimated 246,200 people with dementia living in the community (as opposed to cared accommodation) in 2021 (93,000 men and 153,200 women). This equates to 65% of all people with dementia living in the community (66% of men and 64% of women with dementia) (Figure 2.2).

As people with dementia age, they are more likely to move into residential aged care homes and so the proportion living in the community decreases with increasing age. The majority of people with younger onset dementia (aged less than 65) are living in the community (91% or 20,300 people). Among the older age groups, just under half of people with dementia live in the community (48% of people with dementia aged 85–89 or 32,100 people and 46% aged 90 and over, or 41,600 people). This decrease is more substantial among women than men.

Figure 2.2: Australians living with dementia in 2021: estimated percentage by age, sex and place of residence

Figure 2.2 is a stacked bar graph showing the percentage of people with dementia in Australia who are living in the community and the percentage who are living in cared accommodation in 2021 by age and sex. It shows that the majority of people with dementia aged under 85 are living in the community but this decreases to around half of people living in the community among those aged 85 and over. This decrease is more substantial among women than men.

It is often assumed that people with dementia require care at all times. However, with the appropriate help and support, people with dementia can live independently in their own home, often until their dementia has advanced and care needs become greater.

According to the Survey of Disability, Ageing and Carers (SDAC), of the people with dementia who lived in the community in 2018, 86% lived in private dwellings with other people, while 14% lived alone. Men were more likely to have been living with other people (91%) than women (81%) (Table S2.3). Further information on the SDAC can be found in the Technical notes.

The number of Australians with dementia is projected to more than double by the year 2058

With Australia’s population expected to continue growing and ageing into the future, the number of people with dementia is also expected to rise. Applying the AIHW-derived prevalence rates discussed above to ABS population projections for each year to 2058, it is estimated the number of people with dementia in Australia will more than double over this period—from just over 386,200 in 2021 to 849,300 in 2058 (around 315,500 men and 533,800 women) (Figure 2.3).

This trend is driven by the projected continued growth and ageing of Australia’s population, as the condition is increasingly common in older age. As demographic projections over long periods carry a large degree of uncertainty and this approach assumes that the incidence of dementia (that is, no changes in the rate of new dementia cases in future years) and mortality rates for dementia remain the same, these estimates should be interpreted with caution. Further, recent findings suggest that the official estimated resident population for Australia is less accurate as age increases, especially among those aged 100 and over (Wilson & Temple 2020). Refer to Table S2.4 for more details on the estimated dementia prevalence by age and sex between 2010 and 2058.

Figure 2.3: Australians living with dementia between 2010 and 2058: estimated number by sex and year

Figure 2.3 is a line graph showing the estimated number of males, females and people with dementia in Australia between 2010 and 2058. It shows that the number of people with dementia is expected to continue to increase, due to the projected continued growth and ageing of Australia’s population.

How does dementia prevalence vary by geographic and socioeconomic areas?

Given the lack of suitable data to accurately estimate dementia prevalence at the national level, it isn’t surprising that estimating dementia prevalence at a finer disaggregation is even more difficult. However, the derived age-specific and sex-specific national prevalence rates can be used to illustrate the impact of different age structures and population sizes by state/territory, remoteness and socioeconomic area on how the number of people with dementia varies across Australia.

Figure 2.4 shows the estimated number of people with dementia by state/territory, remoteness, or socioeconomic area based on AIHW estimates for 2019.

Figure 2.4: Australians living with dementia in 2019: estimated number by sex, and geographic or socioeconomic area

Figure 2.4 is a bar graph showing the estimated number of men and women with dementia in Australia in 2021 by state or territory, remoteness and socioeconomic areas. Due to lack of data, the AIHW national age-sex specific rates for dementia were applied to the population in each state, remoteness and socioeconomic area. The numbers of men and women with dementia were highest in the most populous states, New South Wales, Victoria and Queensland, and in Major cities, but were spread evenly across socioeconomic areas. The number of women with dementia is higher than men across all areas shown.

A recent report using nationwide clinical data from 569 general practices found that dementia was similarly present across socioeconomic and remoteness areas in Australia (NPS MedicineWise 2020). These data provide important insights on those people in the community with diagnosed dementia who attend a regular general practice.

International comparisons of dementia prevalence

International comparisons of dementia prevalence statistics are a useful starting point for learning how other nations with similar population profiles are experiencing dementia. The Organisation for Economic Co-operation and Development (OECD) publishes dementia prevalence rate estimates for OECD countries that provide a useful comparison for Australia as most are considered developed, high-income countries. The 2019 OECD dementia prevalence rates were similar to the estimates presented in this report, but used a different methodology and data source. The OECD rates were based on the regional prevalence rates published in the World Alzheimer’s report 2015 and were subject to varying quality of information across regions, so they should only be used for international comparisons. For example, Australasian rates were based on a small sample of older studies while rates for Western Europe were updated to include information from more recent studies.

In 2019, the OECD estimated that the prevalence of dementia in Australia was 14.6 cases per 1,000 population, close to the OECD average of 15.3 per 1,000 population and ranking 17th lowest out of 36 countries (Figure 2.5). Mexico had the lowest rate, half the Australian rate at 7.6 per 1,000 population, whereas Japan’s rate was highest at 24.8 per 1,000 population (OECD 2019). These are unadjusted prevalence rates, meaning that much of the variation in dementia prevalence across countries is due to differences in population age structures, with ageing OECD nations tending to have higher prevalence rates.

Figure 2.5: People living with dementia in Organisation for Economic Co-operation and Development (OECD) member countries in 2019: estimated rate by country

Figure 2.5 is a bar graph showing the estimated rate of dementia in member countries of the Organisation for Economic Co-operation and Development (OECD) in 2019. The rate for Australia was slightly lower than the average rate for OECD countries. Variation in dementia prevalence across countries is due to differences in population age structures, with ageing OECD nations tending to have higher prevalence rates.