Major depression and its association with long-term medical conditions.

OBJECTIVE To replicate previously reported associations between major depressive episodes (MDEs) and long-term medical conditions in a Canadian community sample. METHODS A sample of 2542 household residents was selected using random digit dialing (RDD). Data were collected by telephone interview. The Composite International Diagnostic Interview (CIDI)-Short Form for major depression (CIDI-SFMD) was used to identify MDEs occurring in the previous 12 months. Long-term medical conditions were identified by self-report. RESULTS The prevalence of MDE was elevated in those subjects who reported 1 or more long-term medical conditions. The association was not due to confounding by age, sex, social support, or stressful recent life events. CONCLUSION This study replicates a previously reported association between depressive disorders and long-term medical conditions. These cross-sectional associations suggest that medical conditions may increase the risk of major depression or that major depression may increase the risk of medical conditions. Alternatively, comorbid medical conditions may influence the duration of depressive episodes, or vice versa. These explanations are not mutually exclusive.