Trends in Prevalence of Dementia for People Accessing Aged Care Services in Australia.

BACKGROUND: Studies in some high-income countries have reported a potential decline in the prevalence of dementia. Improvements in cardiovascular health may be contributing to this decline. The objective was to examine trends in prevalence of dementia and survival with dementia for people accessing aged care in Australia.

METHODS: A retrospective study of older people who accessed long-term care 2008-2014 (n = 348,311) and home care 2005-2014 (n = 188,846) in Australia was developed. The age- and sex-standardized prevalence for dementia by year of access to aged care was determined using direct standardization. Generalized linear models were used to determine change in the prevalence of dementia over time and change in 1-year mortality for people who accessed long-term care.

RESULTS: The age- and sex-standardized prevalence (95% confidence interval) of dementia declined from 50.0% (49.6, 50.5) in 2008 to 46.6% (46.0, 47.2) in 2014 for people accessing long-term care (absolute change 2008-2014: -3.8 [-4.6, -3.1]) and for people accessing home care from 25.9% (25.0, 26.5) in 2005 to 20.9% (20.2, 21.7) in 2014 (absolute change 2005-2014: -5.2 [-6.2, -4.1]). This decline in dementia occurred in concurrence with a decline in cerebrovascular disease in long-term care but despite the prevalence of hypertension, diabetes, high cholesterol, malnutrition, obesity, depression, and head injury increasing. For people accessing long-term care, 1-year mortality remained stable over time.

CONCLUSIONS: The decline in prevalence of dementia for people accessing aged care services in Australia is critical to future projection estimates and for planning of services. Further research to determine contributing factors to the decline is needed.