Predictors of Early Discontinuation of Dual-Antiplatelet Therapy: Room for Improvement

Abstract

D rug-eluting stents (DES) have revolutionized the approach to percutaneous coronary interventions and have substantially reduced restenosis compared with bare metal stents. 1,2 Despite their advantages, DES are not without disadvantages. In particular, patients who receive DES remain at risk of a 1% to 2% incidence of stent thrombosis, which is often fatal. 3,4 Dual-antiplatelet therapy (DAT) in the form of a thienopyridine and aspirin improves outcomes in patients who receive DES, 3,5 and early termination of DAT is associated with worse outcomes. 6 Consequently, recommendations for the sirolimus-eluting stent and the paclitaxeleluting stent include a minimum of 12 months of uninterrupted thienopyridine therapy, while maintaining long-term aspirin therapy for the patients' underlying coronary disease. 7 As such, early discontinuation of a thienopyridine should only be considered if bleeding risk substantially outweighs thrombotic risk or considered temporarily if a major invasive procedure is necessary. 7 Article see p 1017While a strong body of evidence and evidence-based guidelines support the importance of continuing DAT for a full year with a DES to improve outcomes and reduce stent thrombosis and the negative consequences of early discontinuation, adherence rates are suboptimal. Ho et al (2007) 8 found that 20% of patients had discontinued clopidogrel therapy within 6 months of receiving a bare-metal stent or DES. Results from the Prospective Registry Evaluating Myocardial Infarction: Events and Recovery Registry showed that 14% of acute coronary syndrome patients had discontinued DAT within the first 30 days following placement of a DES 9 -a period with a high risk of stent thrombosis. 10 Results from the current article by Ferreira-González et al 11 are similar, suggesting that over 14% of patients had permanently or temporarily interrupted at least one antiplatelet therapy (AT) following DES.Medication nonadherence in general and discontinuation of DAT specifically are associated with poor outcomes in high-risk coronary artery disease patients. 12 In fact, the single greatest predictor of stent thrombosis is premature discontinuation of DAT. 6 Studies from Canada have demonstrated higher mortality among patients who delayed filling a clopidogrel prescription after hospital discharge due to formulary restrictions for clopidogrel. 13,14 In a contemporary cohort receiving DES, Ho et al (2010) 15 determined that 1 in 6 patients have a delay in filling clopidogrel after hospital discharge, and this delay was associated with adverse effects. This study noted an increased risk of death or myocardial infarction among patients with any delay in filling clopidogrel after hospital discharge. A large proportion of these adverse events occurred within the first 30 days of hospital discharge, particularly for patients with any delay in filling clopidogrel. These early adverse events coincide with the timing of early stent thrombosis seen in various observational data sets. 16 While there are posited to be many poten...

My Interventional Drug-Eluting Stent Educational App (MyIDEA): Patient-Centered Design Methodology

“…DAPT discontinuation rates are 14-57% [ 7 - 9 ]. Multiple authors have called for research improving adherence to DAPT [ 10 , 11 ], with recognition that patient education is one of the few modifiable factors to reduce risks after a PCI [ 3 , 12 ].…”