Depression as a risk factor for total mortality in the community: a meta-analysis

Aim: There is growing evidence that depression is associated with an increased mortality risk, but results from studies are ambiguous. To investigate whether depression leads to increased mortality, we reviewed the literature on depression and total mortality in the community. We also performed statistical pooling. Methods: We searched Medline and Psychinfo for relevant articles published between January 1966 and December 2000 and checked the references in the articles found in our search. We used the following inclusion criteria: published in English, Dutch or German language; prospective community based studies describing at least total mortality; the presence of a control group and the use of DSM-criteria or criteria resembling DSM in a reasonable way or by a validated and reliable depression questionnaire in the diagnosis of depression. Results: Twenty-four studies were included in our review. Of the 19 studies reporting data on males and females together, nine reported a significant positive association. The majority of studies showed a positive non-significant association between depression and mortality. No significant negative associations were reported. Overall the summary estimated relative risk was 1.56 (1.31-1.85). Conclusions: Our results support the hypothesis of depression being a risk factor for increased total mortality.