Long-term outcomes by clopidogrel duration and stent type in a diabetic population with de novo coronary artery lesions

Objectives The purpose of this study was to determine whether long-term clinical outcomes differed between bare-metal stents (BMS) and drug-eluting stents (DES) by duration of clopidogrel use among diabetic patients. Background There is concern that DES are associated with late adverse events such as death and myocardial infarction (MI) secondary to stent thrombosis. However, data on outcomes in diabetic patients remain limited. Methods We identified 749 patients with diabetes mellitus who underwent stent implantation with either BMS (n = 251) or DES (n = 498) from October 2002 to December 2004. We performed survival analysis on the full cohort and on those event-free from death, MI, or repeat revascularization at 6 months (n = 671). Results By clopidogrel duration, the event rate for death or MI was 3.2% in the > 9-month group, 9.4% in the 6- to 9-month group, and 16.5% in the < 6-month group, p < 0.001. For death alone, the event rate was 0.5% in the > 9-month group, 4.3% in the 6- to 9-month group, and 10.0% in the < 6-month group, p < 0.001. When taking BMS clopidogrel non-users as a referent in the multivariate analysis, the hazard ratio (95% confidence interval [CI]) for death and nonfatal MI for DES clopidogrel users, DES clopidogrel nonusers, and BMS clopidogrel users were: HR 0.22 (95% CI 0.08 to 0.62, p = 0.005), HR 0.39 (95% CI 0.13 to 1.13, p = 0.08), and HR 0.25 (95% CI 0.08 to 0.81, p = 0.02), respectively. Conclusions Longer duration of clopidogrel use was associated with a lower incidence of death or MI in both the BMS and DES groups. Among clopidogrel nonusers, the incidence of death/MI or death did not differ by stent type.