The association between cardiac rehabilitation and mortality risk for myocardial infarction patients with and without depressive symptoms

Background: Post myocardial infarction (MI) depression is associated with reduced adherence to cardiac rehabilitation (CR) and increased mortality risk. The present study investigated whether all cause mortality reduction associated with CR is different for MI patients with and without depressive symptoms. Methods: Data of 2198 post MI patients from the Depression after Myocardial Infarction (DepreMI) study and Myocardial Infarction and Depression Intervention Trial (MIND IT) was used. Depression was assessed at hospitalization, defined as a score >= 10 on the Beck Depression Inventory (BDI). Participation in CR was assessed with a self report questionnaire, 12 months post MI. Cox regression was used to estimate hazard ratios (HR) for all cause mortality, up till 10 years post MI Missing data was imputed, using multiple imputation. Results: 878 (52%) Patients attended CR, 517 (26%) patients had a BDl score >= 10, and 379 (18%) patients died during the follow-up period. Overall, CR was not associated with a lower mortality risk (HR: 0.83; 0.54-1.30; p=0.41), adjusted for age, sex, left ventricle ejection fraction, previous MI, and past or current heart failure. However, there was a significant interaction between depression and CR On mortality (HR: 0.49; 027-0.90; p=0.02). CR was significantly associated with reduced mortality in depressed patients (HR: 0.48; 0.28-0.84; p=0.01), but not in non-depressed patients (HR: 1.09; 0.63-1.89; p=0.74). Limitations: Patients were not randomized to CR. We had no information about the specific reasons of clinicians to offer CR and about the patients' motives to participate. Conclusions: CR was associated with reduced mortality risk only for MI-patients with depression. Clinicians should therefore particularly encourage MI-patients with depression to participate in CR. (C) 2015 Elsevier B.V. All rights reserved