Geriatric depression: a follow-up study of longitudinal course
10 / 1996 - 10 / 2003
[OBJECTIVES:] To determine factors associated with the incidence of geriatric depression in the community; to establish whether similar patterns can be found for prognostic factors related to the course of late-life depression; to investigate possible consequences of late-life depression, such as (a) excess mortality and (b) cognitive decline. [METHODS:] The study is based on data from the Amsterdam Study of the Elderly (AMSTEL). The study population included all individuals, 65-84 years of age, living independently in the city of Amsterdam and registered with a general practitioner at baseline. Of the 4051 subjects who initially responded, 2244 (55.4%) were interviewed again three years later (median 38 months). Mortality data from municipality records were used to cross-check data on non-response, and it was found that 1035 (25,6%) people had died before follow-up. [RESULTS:] Higher age, personal history of depression, death of spouse, health-related factors and comorbid organic or anxiety syndrome showed significant bivariate associations with the incidence of depression. Effect modification by environmental factors was evident; having a partner and, if single, having social support, significantly reduced the impact of functional disabilities on the incidence of depression.Risk factors for incident depression are not similar to factors associated with the prognosis once depression is present. The risk pattern for developing chronic depression is different for men and women. In subjects with a personal history of depression, no associations with prognostic factors were found, whereas in subjects without such vulnerability, chronicity is associated with a number of adverse social, physical and functional conditions. Psychotic depression was found to be associated with excess mortality; 75% of men and 41.4% of women with psychotic depression had died at follow-up. After correction for other explanatory variables, psychotic depression retained a statistically significant relationship with mortality in both men and women. Neurotic depression was associated with a 1.67-fold higher mortality risk in men (95% confidence interval 1.22-2.30), but not in women. Both major and 'minor' depressive syndromes increase the risk of death, especially in elderly men. The study has resulted in the submission of a paper. New data on the 10-year mortality of 3000 depressed community-living elderly people have been collected. In the coming year these data will be analysed, also taking into account the possible causes of death that may be associated with a depressive disorder.