Background: Depression is considered a risk factor for coronary heart disease (CHD) in initially CHD-free populations. Subclinical CHD or other somatic causes of depressive symptoms might account for the association, however.
Methods: In this case-control study, patients had had their first acute myocardial infarction (AMI). The study included 1799 cases, aged 45-70 years, and 2339, age-, gender-, and hospital-catchment-area-matched control subjects. We calculated odds ratios (OR) with 95% confidence intervals (CI) by multivariate logistic regressions to assess the AMI risk associated with a hospitalization for depression.
Results: Forty-seven cases and 22 control subjects had been hospitalized for depression. After adjustment for matching criteria and socioeconomic status, the OR for AMI was 2.9 (1.8-4.9) for ever hospitalized for depression. Patients hospitalized for depression before or after the median time, 15 years and 2 months, between the first hospitalization for depression and AMI, were at similar risk. Adjustment for lifestyle, lipid profile, coagulation, inflammation, prior cardiovascular events, and comorbidity only partly decreased the observed association.
Conclusions: Depression was associated with increased risk for AMI. Subclinical CHD or other somatic causes are unlikely to account for our findings, which also appear not to be explained by established risk factors for AMI.