Abstract 18720: The Impact of Prolonged Clopidogrel Use Beyond 12 Months After Coronary Stenting in Smokers and Non-smokers

Abstract

Background: Cigarette smoking potentiates the antiplatelet effect of clopidogrel. Guidelines recommend clopidogrel for 12 months after percutaneous coronary intervention (PCI) with bare-metal (BMS) or drug-eluting (DES) stents. Whether smoking affects the risk of ischemic events related to clopidogrel use beyond 12 months after PCI is unknown Methods: We identified all PCIs performed in the Veterans Affairs (VA) health system from 2002-2006 and linked the information with the VA pharmacy database. VA and non-VA clinical outcomes were identified by ICD-9 codes from the VA National Patient Care and CMS/Medicare databases. All patients who were event-free at 12 months were followed for death, myocardial infarction (MI), or target vessel revascularization (TVR) up to 4 years following PCI. Prolonged (i.e., > 12 months) vs. clopidogrel use for < 12 months was assessed for each outcome within each stent type using propensity score adjusted inverse probability of weighting (IPW) Cox-proportional hazards analyses. Results: From 2002-2006, 28,507 patients included in the study underwent PCI and were event free at 12 months. Of these, 42% were smokers (n = 11,989) at the index PCI, 51% received a DES (n = 14, 594) and 45% were treated with prolonged clopidogrel use (n = 12,968). Following a 12-month landmark period, 2,194 deaths, 2,288 death or MIs, and 2,010 TVRs occurred. In smokers, prolonged clopidogrel use was associated with a lower risk of death and death or MI with both stent types (interaction p ≤ 0.10). In non-smokers, prolonged clopidogrel use was associated with a lower risk of death (interaction p = 0.04) and death or MI (interaction p = 0.03) in patients receiving DES only (Table). Conclusions: Prolonging clopidogrel more than 12 months after PCI may lower the risk of death or MI in smokers irrespective of stent type and in non-smokers receiving DES only. This study suggests that the duration of clopidogrel use after PCI may be tailored to smoking status and stent-type.