Preoperative depression and mortality in coronary artery bypass surgery: Preliminary findings

Background: There is convincing evidence to suggest that depression significantly increases the risk of mortality following myocardial infarction. There are few data concerning depression as a risk factor for mortality following cardiac surgery. The aim of the present observational study was to determine if preoperative depressive symptoms resulted in an increased risk of late mortality following cardiac surgery. Methods: Preoperative assessments of depressive symptoms were performed on 158 patients undergoing coronary artery bypass surgery. Elevated preoperative depression symptoms were defined as a depression anxiety stress scale score of greater than or equal to 10. Results: Twenty-four of the 158 patients (15.2%) were classified as having elevated preoperative depressive symptoms. Patients were followed for a median of 25 months (range: 4-38 months). Three of the 24 patients (12.5%) with preoperative depressive symptoms died within the follow-up period, compared with three of the 134 (2.2%) non-depressed patients (odds ratio: 6.24; 95% CI: 1.18-32.98; P = 0.046). There were no other group differences on variables including population demographics, medical risk factors, surgical parameters, and indices of postoperative morbidity. Conclusions: Elevated depressive symptoms before coronary bypass surgery may be a significant predictor of late death. Prospective studies evaluating the prevalence of depressive symptoms in cardiac surgical patients and their effect on long-term outcome must be undertaken.