Objective: The reporting of depressive symptoms following myocardial infarction may be confounded by complaints originating from the myocardial infarction. Therefore, it is difficult to estimate the effects of post-myocardial infarction depression and its treatment on cardiovascular prognosis. The authors' goal was to study the relationship between depressive symptom dimensions following myocardial infarction and both somatic health status and prospective cardiovascular prognosis.
Method: In two studies of myocardial infarction patients (N=494 and 1,972), the Beck Depression Inventory was used to determine the dimensional structure of depressive symptoms following myocardial infarction. Three symptom dimensions-somatic/affective, cognitive/affective, and appetitive-were compared with baseline left ventricular ejection fraction, Charlson comorbidity index, Killip class, and previous myocardial infarction. The relationship between depressive symptom dimensions and prospective cardiovascular mortality and cardiac-related readmissions was also examined (mean follow-up duration=2.5 years).
Results: Somatic/affective symptoms were associated with poor health status (left ventricular ejection fraction, Charlson comorbidity index, Killip class, and previous myocardial infarction) and predicted cardiovascular mortality and cardiac events. Cognitive/affective symptoms were only marginally associated with somatic health status and not with cardiovascular death and cardiac events. Appetitive symptoms were related to somatic health status but did not predict cardiovascular death or cardiac events.
Conclusions: Somatic/affective depressive symptoms following myocardial infarction were confounded by somatic health status yet were prospectively associated with cardiac prognosis even after somatic health status was controlled. Cognitive/affective depressive symptoms were only marginally related to health status and not to cardiac prognosis. These findings suggest that treatment of depression following myocardial infarction might improve cardiovascular prognosis when it reduces somatic/affective symptoms.