prevalence
Last reviewed 01/2018
The majority of old people are not ill - 80% of the over- 80's don't have any cognitive impairment, for example - and are not dependent - only 6% of the over-65's live in institutional care, 41% of them are living with a spouse and 32% live alone.
Figures for the prevalence of psychiatric illness have an exact meaning only in relation to the definition of illness used in the prevalence study, but as a rough guide about 10% of the over-65's can be regarded as having some cognitive impairment (severe in 5%, moderate in 5%). The prevalence of cognitive impairment is greater in the older age groups and in the over-80's is roughly 20%. Depression is the commonest functional illness (clear-cut severe depressive illnesses occurring in 1 to 2% of the over-65's, and depression of lesser severity in roughly 7 to 12%). Paranoid illnesses, mania and hypomania, anxiety states, and other neurotic and personality disorders together make up perhaps another 5 to 10% of the population of the over-65's.
adapted from : 'Student Notes', Oxford University Department of Psychiatry; 1991.