Impact of diabetes mellitus on long-term outcomes in the drug-eluting stent era

Background: Diabetes mellitus is associated with an increased risk of restenosis, stent thrombosis, and death after percutaneous coronary interventions. Little is known about the late outcome of patients with diabetes mellitus who receive drug-eluting stents (DES). Methods: This study includes a prospective database of 2557 consecutive patients with coronary artery disease who underwent DES implantation in native coronary arteries in 2 German hospitals. The primary end points of the study were mortality and clinical restenosis (target lesion revascularization). Secondary end points were binary angiographic restenosis, stent thrombosis, and the composite of death or myocardial infarction. Results: Within a median follow-up period of 2.3 years, stent thrombosis occurred in 14 patients with diabetes versus 17 patients without diabetes: 3-year Kaplan-Meier estimates of stent thrombosis were 2.2% versus 1.0%, with a relative risk of 2.17 (95% CI 1.09-4.33, P = .027). Binary angiographic restenosis was observed in 87 patients with diabetes and 208 patients without diabetes (15.2% vs 13.5%, P = .32). Target lesion revascularization was needed in 93 patients with diabetes and 219 patients without diabetes (12.8% vs 12.0%, P = .56). There were 93 deaths among diabetic patients versus 118 deaths among nondiabetic patients: 3-year Kaplan-Meier estimates of mortality were 17.3% versus 7.8%, with a relative risk of 2.10 (95% CI 1.61-2.74, P < .001). After adjustment in the multivariable analyses, diabetes remained an independent predictor of 3-year mortality with a hazard ratio of 1.63 (95% CI 1.23-2.17, P < .001), but not of angiographic (P = .92) or clinical restenosis (P = .97). Conclusion: Although DES attenuate diabetes-associated excess risk of restenosis, risk of death and thrombotic complications remains higher in patients with diabetes than in nondiabetic patients in the DES era.