Is there an increased risk of dying after depression?

Abstract

Although a lot of research has been performed on the relation between depression and subsequent mortality, the results show contradictory findings. In this study, the authors investigated mortality in depressed people compared with nondepressed people in a large-scale retrospective cohort study based in general practice in the province of Limburg, the Netherlands. All subjects diagnosed with depression between 1975 and 1990 were included and compared with subjects matched on birth year who never were diagnosed with depression. Follow-up ended on April 30, 2000. Hazard ratios and their 95% confidence intervals were calculated using stratified Cox proportional hazards models adjusted for age, sex, and socioeconomic status. Subgroups based on sex and age at the diagnosis of depression were evaluated separately. A total of 68,965 patients were followed for an average of 15 years. Among 1,362 depressed subjects 132 died, and among 67,603 nondepressed subjects 4,256 died. The adjusted hazard ratio for depressed versus nondepressed subjects was 1.39 (95% confidence interval: 1.16, 1.65). A significant interaction was observed between the age at diagnosis of depression and sex. A moderate positive association between depression and subsequent mortality was identified.