Mortality and Morbidity in Diabetic and Nondiabetic Patients During a 2-Year Period After Coronary Artery Bypass Grafting

Abstract

OBJECTIVE To describe mortality and morbidity during a 2-year period after coronary artery bypass grafting (CABG) among diabetic and nondiabetic patients. RESEARCH DESIGN AND METHODS All the patients in western Sweden in whom CABG was undertaken between June 1988 and June 1991 and in whom concomitant procedures were not performed were registered prospectively. The study was a prospective follow-up. RESULTS Diabetic patients (n = 268) differed from nondiabetic patients (n = 1,859) in that more women were included, and the patients more frequently had a previous history of myocardial infarction (MI), hypertension, congestive heart failure, intermittent claudication, and obesity. Diabetic patients more frequently required reoperation and had a higher incidence of peri- and postoperative neurological complications. Mortality during the 30 days after CABG was 6.7% in diabetic patients versus 3.0% in nondiabetic patients (P < 0.01). Mortality between day 30 and 2 years was 7.8 and 3.6%, respectively (P < 0.01). During 2 years of follow-up, a history of diabetes appeared to be a significant independent predictor of death. Whereas the development of MI after discharge from the hospital did not significantly differ between the two groups; 6.3% of diabetic patients developed stroke versus 2.5% in nondiabetic patients (P < 0.001). CONCLUSIONS Diabetic patients have a mortality rate during the 2-year period after CABG that is about twice that of nondiabetic patients during both the early and late phase after the operation.