Effect of diabetes on outcome and changes in quality of life after coronary artery bypass grafting

Background. An increasing proportion of patients undergoing coronary artery bypass grafting are diabetics who are known to carry a higher mortality and morbidity in association with operation, but data on whether health-related quality of life improves similarly after coronary artery bypass grafting in diabetic and nondiabetic patients are limited. We assessed in detail changes in health-related quality of life (RAND-36 Health Survey) during the first year after coronary artery bypass grafting. Methods. Seventy-four of the 508 patients (14.6%) operated on in a single institution had a history of diabetes and were compared to nondiabetics. The RAND-36 Health Survey was used as an indicator of quality of life. Assessments were made preoperatively and repeated 12 months later. Results. Thirty-day mortality was 2.7% versus 1.6% (p 0.511) and one-year survival was 94.6% versus 97.0% (p = 0.287) in the diabetics and nondiabetics, respectively. Diabetics improved significantly (p < 0.005) in seven, nondiabetics (p < 0.001) in all eight RAND-36 dimensions. Physical component summary and mental component summary scores on the RAND-36 improved significantly (p < 0.001) in diabetics as well as in nondiabetics. Both groups experienced closely similar freedom from anginal symptoms at one year (86.2% vs 90.5%, p = 0.280). Conclusions. Although diabetic patients differ from nondiabetics having slightly inferior quality of life before and one year after coronary artery bypass grafting, they gain similar improvement of quality of life in one year after surgery when compared to nondiabetics.