Effective treatment of depression improves post-myocardial infarction survival

AIM: To examine the contribution of treatment resistant depression(TRD) to mortality in depressed postmyocardial infarction(MI) patients independent of biological and social predictors.METHODS: This secondary analysis study utilizes the Enhancing Recovery in Coronary Heart Disease(ENRICHD) clinical trial data.From 1834 depressed patients in the ENRICHD study,there were 770 depressed post-MI patients who were treated for depression.In this study,TRD is defined as having a less than 50% reduction in Hamilton Depression(HAM-D) score from baseline and a HAM-D score of greater than 10 in 6 mo after depression treatment began.Cox regression analysis was used to examine the independent contributions of TRD to mortality after controlling for the biological and social predictors.RESULTS: TRD occurred in 13.4%(n = 103) of the 770 patients treated for depression.Patients with TRD were significantly younger in age(P = 0.04)(mean = 57.0 years,SD = 11.7) than those without TRD(mean = 59.2 years,SD = 12.0).There was a significantly higher percentage of females with TRD(57.3%) compared to females without TRD(47.4%) [χ2(1) = 4.65,P = 0.031].There were significantly more current smokers with TRD(44.7%) than without TRD(33.0%) [χ2(1) = 7.34,P = 0.007].There were no significant differences in diabetes(P = 0.120),history of heart failure(P = 0.258),prior MI(P = 0.524),and prior stroke(P = 0.180) between patients with TRD and those without TRD.Mortality was 13%(n = 13) in patients with TRD and 7%(n = 49) in patients without TRD,with a mean follow-up of 29 mo(18 mo minimum and maximum of 4.5 years).TRD was a significant independent predictor of mortality(HR =1.995; 95%CI: 1.011-3.938,P = 0.046) after controlling for age(HR = 1.036; 95%CI: 1.011-1.061,P = 0.004),diabetes(HR = 2.912; 95%CI: 1.638-5.180,P < 0.001),heart failure(HR = 2.736; 95%CI: 1.551-4.827,P = 0.001),and smoking(HR = 0.502; 95%CI: 0.228-1.105,P = 0.087).CONCLUSION: The analysis of TRD in the ENRICHD study shows that the effective treatment of depression reduced mortality in depressed post-MI patients.It is important to monitor the effectiveness of depression treatment and change treatments if necessary to reduce depression and improve cardiac outcomes in depressed post-MI patients.