Relation of Effective Anticoagulation in Patients With Atrial Fibrillation to Stroke Severity and Survival (from the National Acute Stroke Israeli Survey [NASIS])

Although the benefit of antithrombotic therapy for stroke prevention in atrial fibrillation (AF) is well recognized, its potential effect on stroke severity and outcome is less well established. Our objective was to examine the effect of preadmission antithrombotic therapy on stroke severity and outcome in patients with AF within a large comprehensive nationwide stroke survey. The data from consecutive patients with AF admitted with acute ischemic stroke or transient ischemic attack during a 2-month period were collected. The patients were categorized into 4 groups according to the use of preadmission antithrombotic therapy: no antithrombotic therapy, antiplatelet therapy, warfarin with an admission international normalized ratio (INR) 5) stratified by antithrombotic therapy use was 70% for no antithrombotic therapy use, 55% for antiplatelet therapy use, 59% for warfarin with an INR 3) or death at discharge, with corresponding adjusted odds ratios of 4.1 (95% CI 1.8 to 9.9), 2.1 (95% CI 1.0 to 4.6), and 1.5 (95% CI 0.6 to 3.5), and 1-year mortality, with corresponding adjusted ORs of 2.4 (95% CI 0.9 to 6.7), 1.9 (95% CI 0.8 to 5.0), and 2.2 (95% CI 0.8 to 6.2). In conclusion, in addition to its established benefit for stroke prevention, effective anticoagulation therapy is associated with decreased stroke severity and better functional outcome and survival in patients with AF presenting with acute brain ischemia.