Antithrombotic Therapy Use at Discharge and 1 Year in Patients With Atrial Fibrillation and Acute Stroke

Abstract

Background and Purpose—: Current American Heart Association/American Stroke Association guidelines identify warfarin use as a class IA indication in patients with atrial fibrillation (AF) and ischemic stroke (IS) or transient ischemic attack (TIA). However, few studies have examined factors associated with long-term antithrombotic therapy use in IS/TIA patients with AF. Methods—: We utilized the Get With The Guidelines–Stroke national quality improvement registry and the Adherence eValuation After Ischemic Stroke Longitudinal (AVAIL) Registry to examine patterns of antithrombotic use at discharge and at 12 months in IS/TIA patients with AF. A multivariate logistic regression model was developed to identify predictors of warfarin use in this patient population at 12 months. Results—: Of the 2460 IS/TIA patients, 291 (11.8%) had AF, of which 5.5% of patients were discharged on aspirin alone, 49.1% on warfarin alone, 1.4% on clopidogrel alone, 34.7% on warfarin plus aspirin, 2.1% on aspirin plus clopidogrel, and 1.0% on aspirin plus clopidogrel plus warfarin. Paradoxically, there was a decrease in the rate of warfarin use in patients with a CHADS ₂ score >3. The only factor associated with warfarin use at 12-month follow-up was male gender (adjusted odds ratio, 2.27; confidence interval, 1.22–4.35; P =0.01). Conclusions—: Overall, the use of warfarin therapy is high at discharge in IS/TIA patients with AF; however, there was a decrease in the rate of warfarin use in patients with a CHADS ₂ score >3. Compared to women, men were more likely to be on warfarin at 1 year after the index stroke event. Therefore, opportunities exist to improve antithrombotic use in all IS/TIA patients with AF.