Post-myocardial infarction depression: increased hospital admissions and reduced adoption of secondary prevention measures--a longitudinal study.

Objective: Depression is prevalent in the aftermath of myocardial infarction (MI), and has been linked with mortality however few studies have investigated hospital admissions in MI survivors. Using a prospective cohort design, we examined the long-term relationship between depressive symptoms, post-MI hospital admissions and secondary prevention measures, in order to assess the burden of post-MI depression on patients and the healthcare system.

Methods: A cohort of 632 patients aged ≤65 years, admitted for first-ever MI to 1 of the 8 hospitals in central Israel, was followed up for 10-13 years. Depressive symptoms were assessed at initial hospitalization using the Beck Depression Inventory. Rehospitalization and adoption of secondary prevention measures were recorded throughout follow-up.

Results: Depressive symptoms were significantly associated with days of hospitalization during follow-up (RR, 1.37, CI, 1.26-1.49), an association which remained significant after risk adjustment (RR, 1.14, CI, 1.04-1.26). The association appeared stronger for cardiac-related admissions than for other, non-cardiac admissions. Depressed patients were less likely to stop smoking (OR, 0.75, CI, 0.60-0.94), be physically active (OR, 0.80, CI, 0.69-0.94) and participate in cardiac rehabilitation (OR, 0.74, CI, 0.59-0.92).

Conclusion: Post-MI depressive symptoms were shown to be associated with increased hospital admissions, particularly cardiac admissions, and with reduced adoption of secondary prevention behaviors. These findings have implications for patients' prognosis and quality of life and for healthcare costs. Depressive symptoms, even at the sub-clinical level, should be monitored in post-MI patients in order to identify those at greater risk of rehospitalization.