Effects of antidepressant medication on morbidity and mortality in depressed patients after myocardial infarction

Background: Depression after myocardial infarction (MI) is associated with higher morbidity and mortality. Although antidepressants are effective in reducing depression, their use in patients with cardiovascular disease remains controversial. Objective: To undertake a secondary analysis to determine the effects of using antidepressants on morbidity and mortality in post-MI patients who participated in the Enhancing Recovery in Coronary Heart Disease study. Design: Observational secondary analysis. Setting: Eight academic sites. Patients: The Enhancing Recovery in Coronary Heart Disease clinical trial randomized 2481 depressed and/or socially isolated patients from October 1, 1996, to October 31, 1999. Depression was diagnosed using a structured clinical interview. This analysis was conducted on the 1834 patients enrolled with depression (849 women and 985 men). Intervention: Use of antidepressant medication. Main Outcome Measures: Event-free survival was defined as the absence of death or recurrent MI. All-cause mortality was also examined. To relate exposure to antidepressants to subsequent morbidity and mortality, the data were analyzed using a time-dependent covariate model. Results: During a mean follow-up of 29 months, 457 fatal and nonfatal cardiovascular events occurred. The risk of death or recurrent MI was significantly lower in patients taking selective serotonin reuptake inhibitors (adjusted hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.38-0.84), as were the risk of all-cause mortality (adjusted HR, 0.59; 95% CI, 0.37-0.96) and recurrent MI (adjusted HR, 0.53; 95% CI, 0.32-0.90), compared with patients who did not use selective serotonin reuptake inhibitors. For patients taking non-selective serotonin reuptake inhibitor antidepressants, the comparable HRs (95% CIs) were 0.72 (0.44-1.18), 0.64 (0.34-1.22), and 0.73 (0.38-1.38) for risk of death or recurrent MI, all-cause mortality, or recurrent MI, respectively, compared with nonusers. Conclusions: Use of selective serotonin reuptake inhibitors in depressed patients who experience an acute MI might reduce subsequent cardiovascular morbidity and mortality. A controlled trial is needed to examine this important issue.