Depression and cardiac mortality - Results from a community-based longitudinal study

Background: Depression may be a potential risk factor for subsequent cardia c death. The impact of depression on cardiac mortality has been suggested t o depend on cardiac disease status, and to be stronger among cardiac patien ts. This study examined and compared the effect of depression on cardiac mo rtality in community-dwelling persons with and without cardiac disease. Methods: A cohort of 2847 men and women aged 55 to 85 years was evaluated f or 4 years. Major depression was defined according to psychiatric DSM-III c riteria. Minor depression was defined by Center for Epidemiologic Studies-D epression Scale scores of 16 or higher. Effects of minor and major depressi on on cardiac mortality were examined separately in 450 subjects with a dia gnosis of cardiac disease and in 2397 subjects without cardiac disease afte r adjusting for demographics, smoking, alcohol use, blood pressure, body ma ss index, and comorbidity. Results: Compared with nondepressed cardiac patients, the relative risk of subsequent cardiac mortality was 1.6 (95% confidence interval ICI], 1.0-2.7 ) for cardiac patients with minor depression and 3.0 (95% CI, 1.1-7.8) for cardiac patients with major depression, after adjustment for confounding va riables. Among subjects without cardiac disease at baseline, similar increa sed cardiac mortality risks were found for minor depression (1.5 [95% CI, 0 .9-2.61) and major depression (3.9 [95% CI, 1.4-10.9]). Conclusion: Depression increases the risk for cardiac mortality in subjects with and without cardiac disease at baseline. The excess cardiac mortality risk was more than twice as high for major depression as for minor depress ion.