Prevalence and predictors of premature discontinuation of dual antiplatelet therapy after drug-eluting stent implantation: Importance of social factors in Asian patients

Abstract

Aim: Premature discontinuation of antiplatelet therapy is an independent predictor of late stent thrombosis. We sought to determine the prevalence and predictors of premature discontinuation of antiplatelet therapy after drug-eluting stent implantation among patients in Asia. Methods: A total of 207 consecutive patients who underwent drug-eluting stent implantation at our institution was followed up after 1year. Premature discontinuation of antiplatelet therapy was defined as omission of aspirin and/or clopidogrel for 1week or more. Results: Four (1.9%) patients died and the remaining 203 patients formed the study population. Prevalence of premature discontinuation of antiplatelet therapy was 12.8% (n= 26, aspirin, n= 12; clopidogrel, n= 9; both, n= 5). The median duration between stent implantation and discontinuation of antiplatelet therapy was 2.8months. Reasons for discontinuation included cost (n= 1), gastric discomfort (n= 1), allergy (n= 3), bleeding (n= 3), advice from doctors (n= 7) and no reason (n= 11). Logistic regression showed that living alone was the only independent predictor of premature discontinuation of dual antiplatelet therapy (50.0% vs 11.3%, P= 0.001). Conclusion: Among Asian patients who have undergone drug-eluting stent implantation, 12.8% discontinued dual antiplatelet therapy within 12months. Living alone is associated with a fivefold increase in risk of premature drug discontinuation. © 2011 The Authors. Internal Medicine Journal © 2011 Royal Australasian College of Physicians.