Changes in cognitive versus somatic symptoms of depression and event-free survival following acute myocardial infarction in the Enhancing Recovery In Coronary Heart Disease (ENRICHD) study

BackgroundRandomized controlled trials focusing on the effects of antidepressant treatment in cardiac patients have found modest effects on depressive symptoms but not on cardiac outcomes. A secondary analysis was conducted on data from the Enhancing Recovery in Coronary Heart Disease trial to assess whether changes in somatic or cognitive depressive symptoms following acute MI predicted event-free survival and whether the results differed per treatment arm (cognitive behavior therapy or care as usual).MethodsPatients who met depression criteria and completed the 6th month depression assessment (n=1254) were included in this study. Measurements included demographic and clinical data and the Beck Depression Inventory at baseline and 6 months. The primary endpoint was a composite of recurrent MI and mortality over 2.4 years (standard deviation=0.9 years).ResultsPositive changes (per 1 point increase) in somatic depressive symptoms (HR: 0.95; 95% CI: 0.92-0.98; p=0.001) but not in cognitive depressive symptoms (HR: 0.98; 95% CI: 0.96-1.01; p=0.19) were related to a reduced risk of recurrent MI and mortality after adjustment for baseline depression scores. There was a trend for an interaction effect between changes in somatic depressive symptoms and the intervention (p=0.08). After controlling for demographic and clinical variables, the association between changes in somatic depressive symptoms and event-free survival remained significant in the intervention arm (HR: 0.93; 95% CI: 0.88-0.98; p=0.01) only.LimitationsSecondary analyses.ConclusionsChanges in somatic depressive symptoms, and not cognitive symptoms, were related to improved outcomes in the intervention arm, independent of demographic and clinical variables.