Influence of diabetes mellitus on long-term (five-year) outcomes of drug-eluting stents and coronary artery bypass grafting for multivessel coronary revascularization.

Diabetes mellitus is a major risk factor for coronary artery disease (CAD) and for diffuse and progressive atherosclerosis. We evaluated the outcomes of drug-eluting stent (DES) placement and coronary artery bypass grafting (CABG) in 891 diabetic patients (489 for DES implantation and 402 for CABG) and 2,151 nondiabetic patients (1,058 for DES implantation and 1,093 for CABG) with multivessel CAD treated from January 2003 through December 2005 and followed up for a median 5.6 years. Outcomes of interest included death; the composite outcome of death, myocardial infarction (MI), or stroke; and repeat revascularization. In diabetic patients, after adjusting for baseline covariates, 5-year risk of death (hazard ratio 1.01, 95% confidence interval 0.77 to 1.33, p = 0.96) and the composite of death, MI, or stroke (hazard ratio 1.03, 95% confidence interval 0.80 to 1.31, p = 0.91) were similar in patients undergoing DES or CABG. However, rate of repeat revascularization was significantly higher in the DES group (hazard ratio 3.69, 95% confidence interval 2.64 to 5.17, p <0.001). These trends were consistent in nondiabetic patients (hazard ratio 0.80, 95% confidence interval 0.55 to 1.16, p = 0.23 for death; hazard ratio 0.77, 95% confidence interval 0.56 to 1.05, p = 0.10 for composite of death, MI, or stroke; hazard ratio 2.77, 95% CI 1.95 to 3.91, p <0.001 for repeat revascularization). There was no significant interaction between diabetic status and treatment strategy on clinical outcomes (p for interaction = 0.36 for death; 0.20 for the composite of death, MI, or stroke; and 0.40 for repeat revascularization). In conclusion, there was no significant prognostic influence of diabetes on long-term treatment with DES or CABG in patients with multivessel CAD.