Thrombosis, bleeding and DAPT non-adherence in the EDUCATE registry

Abstract

Background: We determined predictors and outcomes of dual antiplatelet therapy (DAPT) non-adherence in the first year after Endeavor zotarolimus-eluting stent (E-ZES) placement in a broadly inclusive prospective multicenter registry. Methods: 2265 patients were evaluated after successful implantation of at least one E-ZES. At 12 months, event-free, compliant patients will be randomized to 12 vs 30 months of DAPT as part of the independent DAPT Study. Predictors of Any Non-Adherence (ANA) at 6 months and 1 year were analyzed by multivariable analysis; the association between ANA at 6 vs 12 months and thrombotic events was investigated. Results: Patients were 30% female, 34% diabetic, and 64% had stable coronary syndromes. Aspirin 81 mg qd and clopidogrel 75 qd was the most common DAPT. ANA occurred in 208 (9.6%) patients at 6 months and 378 patients (18.5%) at 1 year. Major bleeding (OR 9.48, p <0.0001) and non-cardiac surgery (OR 3.24, p=0.004) were significant predictors of ANA at 6 months. ANA within 6 months of PCI was associated with an increased risk of stent thrombosis (ST, 5.7 vs 1.4%, p <0.001) and death/MI/ST (9.9% vs 4.2%, p=0.002) at 1 year. ANA at 6 months was also a significant predictor of death/MI/ST in the multivariate model (OR 1.96, p=0.016). ANA between 6 and 12 months did not increase the risk of ST or death/MI/ST. Conclusions: One year DAPT ANA involves nearly 1 in 5 patients. DAPT ANA within 6 months after PCI is an independent predictor of increased risk for thrombosis. Major bleeding and non-cardiac surgery were independent predictors of DAPT ANA at 6 months.