Triple antithrombotic therapy is the independent predictor for the occurrence of major bleeding complications: analysis of percent time in therapeutic range.

BACKGROUND Triple antithrombotic therapy increases the risk of bleeding events in patients undergoing percutaneous coronary intervention. However, it remains unclear whether good control of percent time in therapeutic range is associated with reduced occurrence of bleeding complications in patients undergoing triple antithrombotic therapy. METHODS AND RESULTS This study included 2648 patients (70 ± 11 years; 2037 men) who underwent percutaneous coronary intervention with stent in the Ibaraki Cardiovascular Assessment Study registry and received dual antiplatelet therapy with or without warfarin. Clinical end points were defined as the occurrence of major bleeding complications (MBC), major adverse cardiac and cerebrovascular event, and all-cause death. Among these 2648 patients, 182 (7%) patients received warfarin. After a median follow-up period of 25 months (interquartile range, 15-35 months), MBC had occurred in 48 (2%) patients, major adverse cardiac and cerebrovascular event in 484 (18%) patients, and all-cause death in 206 (8%) patients. Multivariable Cox regression analysis revealed that triple antithrombotic therapy was the independent predictor for the occurrence of MBC (hazard ratio, 7.25; 95% confidence interval, 3.05-17.21; P<0.001). The time in therapeutic range value did not differ between the patients with and without MBC occurrence (83% [interquartile range, 50%-90%] versus 75% [interquartile range, 58%-87%]; P=0.7). However, the mean international normalized ratio of prothrombin time at the time of MBC occurrence was 3.3 ± 2.1. Triple antithrombotic therapy did not have a predictive value for the occurrence of all-cause death (P=0.1) and stroke (P=0.2). CONCLUSIONS Triple antithrombotic therapy predisposes patients to an increased risk of MBC regardless of the time in therapeutic range.