The prevalence of depressive disorders and the distribution of depressive symptoms in later life: a survey using Draft ICD-10 and DSM-III-R.

The point prevalence of depressive disorders was estimated in a sample of persons aged 70 years and over, which included both those living in the community and those in institutional settings. Lay interviewers administered the Canberra Interview for the Elderly to the subjects and their informants. The point prevalence of depressive episodes as defined by the Draft ICD-10 diagnostic criteria was 3.3%. The rate for DSM-III-R major depressive disorder was 1.0%. The latter prevalence rate is similar to those reported elsewhere for the elderly. Evidence is accumulating that older persons may indeed have low rates for depressive disorders at the formal case level. Possible reasons for this finding are offered. A scale for depressive symptoms, based exclusively on those specified in Draft ICD-10 and DSM-III-R, showed that the elderly do experience many depressive symptoms. Contrary to expectation, these did not increase with age. The number of depressive symptoms was correlated with neuroticism, poor physical health, disability and a history of previous depression. Attention now needs to be directed to the clinical significance of depressive symptoms below the case level in elderly persons.