Abstract 3719: Long-term Impact of Diabetes in Patients Undergoing Isolated Coronary Artery Bypass Graft Surgery
Background: The long-term effects of diabetes and diabetic-related co-morbidities in patients undergoing coronary artery bypass grafting(CABG) remains unclear.
Objective: To identify the impact of diabetes and related co-morbidities (namely renal failure (RF), peripheral vascular disease (PVD), and low ejection fraction (<35%, LEF)) on the long-term survival of patients undergoing CABG surgery.
Methods: A study was conducted on 10 203 survivors of primary isolated CABG surgery between 1992 and 2002 in a single institution, based on prospectively collected data. There were 2824 diabetic and 7379 non-diabetic patients. The date and cause of death were obtained from the regional statistics Institute in 2004. The mean follow up was 4.6+ 3.1 years. Survival was assessed in diabetic and non-diabetic patients who were subsequently stratified and compared in subgroups with or without RF, PVD, LEF.
Results: During follow-up, there were 320 (11.3%) and 623 (8.4%) deaths from all causes in diabetic and non-diabetic patients, respectively. Actuarial survival at ten years was lower in diabetic vs. non-diabetic patients (71.1% vs. 81.0% p <0.0001). However, 10-year freedom from cardiac-related death was similar in diabetic patients with no associated co-morbidities and non-diabetic patients up to 10 years (89.8% vs 91.5% p=0.21) following surgery, and became significantly lower thereafter (p=0.03). RF, PVD and LEF had a similar impact on 10-year survival reduction of both diabetic and non-diabetic patients (RF: 77.8% vs 76.2%, PVD: 96.2% vs 90.1%, LEF: 72.6% vs 79.2%, p=NS for all). The combined presence of these co-morbidities resulted in more significant (p<0.001) but not statistically different decreases in survival for both populations (RF+PVD: 68.2% vs 77.8%, LEF+PVD: 76.2% vs 76.4%, RF+LEF: 70.1% vs 70.0%, for diabetic vs non-diabetic patients respectively).
Conclusion: Long-term survival of diabetic patients without co-morbidities is the same as that of non-diabetic patients undergoing CABG surgery in the first 10 years following the procedure. In both groups, 10-year survival is similarly affected by the presence and number of co-morbidities such as RF, PVD, LEF.