The incidence of first-onset depression in a population followed from the age of 70 to 85.
BACKGROUND
Due to the limited data available, it is not clear whether the incidence of first-onset depression varies with age in the elderly.


METHODS
A representative sample of individuals born 1901-2 (N = 392) was examined at the ages of 70, 75, 79, 81, 83 and 85 years by psychiatrists using a semi-structured schedule. Information on depressive episodes was also collected from self-report and examination of case records. Depression was diagnosed according to the DSM-III-R criteria.


RESULTS
The incidence of depression was 12 per 1,000 person-years in men and 30 per 1,000 person-years in women between the ages of 70 and 85 (sex difference P = 0.001). The incidence increased from 17 per 1,000 person-years (men 8.7, women 23.2, P = 0.007) between the ages of 70 and 79 to 44 per 1,000 person years (men 27.0, women 52.8, P = 0.166) between 79 and 85 (age difference: RR 2.6, P < 0.001; men RR 3.1, P = 0.036; women RR 2.3, P = 0.003). A diagnosis of depression was associated with increased mortality and refusal rate during the 15-year follow-up. Previous episodes of depression were associated with an increased risk of further episodes. The prevalence of depression increased from 5.6% at the age of 70 to 13.0% at the age of 85. The lifetime prevalence of depression was 23% in men and 45% in women.


CONCLUSIONS
Both the incidence and prevalence of depression increased with age in this longitudinally followed birth cohort, and the incidence was higher in women than in men.
Paĺsson
S P
SP
Institute of Clinical Neuroscience, Department of Psychiatry, Sahlgrenska University Hospital, Göteborg University, Sweden.
Ostling
S
S
Skoog
I
I
D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002391:Catchment Area, Health; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology