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

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 1 year. Premature discontinuation of antiplatelet therapy was defined as omission of aspirin and/or clopidogrel for 1 week 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 2.8 months. 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 12 months. Living alone is associated with a fivefold increase in risk of premature drug discontinuation.