Dementia rates low in younger age groups, then increase greatly

Dementia rates are low among those 65 to 69, but they increase with age. Prevalence more than doubles every 5 years among seniors, from less than 1% in seniors 65 to 69, to about 25% among those 85 and older.

Source
Public Health Agency of Canada. Public Health Infobase: Canadian Chronic Disease Surveillance System (CCDSS). Accessed February 28, 2018.
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