Effect of Depression on Late (8 years) Mortality After Myocardial Infarction

Depression during hospitalization for myocardial infarction (MI) is associated with subsequent mortality, but whether this risk persisted long term is not well studied. This study was performed to determine whether depression during hospitalization for MI, which predicted mortality at 4 months, predicted mortality 8 years later. This was a prospective observational study of 284 hospitalized patients with MI. Major depression and dysthymia were assessed using structured interview for Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition, and depressive symptoms, using the Beck Depression Inventory. Mortality was determined using the Social Security Death Index. Mean age during MI hospitalization was 64.8 years, 43.0% of patients were women, 66.7% had hypertension, and 35.7% had diabetes mellitus. Any depression (major depression, dysthymia, and/or Beck Depression Inventory score ≥10) was present in 76 patients (26.8%). The 8-year mortality rate was 47.9% (136 deaths). Any depression at the time of MI was not associated with mortality at 8 years in unadjusted (hazard ratio 1.25, 95% confidence interval 0.87 to 1.81, p = 0.22) or multivariate models (hazard ratio 0.76, 95% confidence interval 0.47 to 1.24, p = 0.27). In conclusion, depression after MI was associated with increased short-term mortality, but its relation with mortality over time appeared to wane, at least in a group of older patients who had multiple co-morbidities.