Warfarin significantly reduced the incidence of ischemic stroke compared to aspirin (4.2% vs 12.9%, P=0.008) in patients with nonvalvular atrial fibrillation and a CHADS2 score of 1.
Cohort (n=422)
Does warfarin reduce the incidence of ischemic stroke compared to aspirin without increasing bleeding complications in patients with nonvalvular atrial fibrillation and a CHADS2 score of 1?
In patients with nonvalvular atrial fibrillation and a CHADS2 score of 1, warfarin is superior to aspirin for preventing ischemic stroke without increasing major bleeding, though it does increase minor bleeding.
Absolute Event Rate: 4.2% vs 12.9%
p-value: p=0.008
BACKGROUND: The revised ACC/AHA/ESC 2006 guideline recommends either aspirin or warfarin for the prevention of ischemic stroke in patients with atrial fibrillation (AF) in CHADS(2) score 1. We hypothesized that warfarin is superior to aspirin therapy for the prevention of stroke without increasing bleeding complication in AF patients with CHADS(2) score 1. METHODS AND RESULTS: Among 1,502 patients (mean 62.4 +/- 13.8 years old, male 65.4%) who were treated for nonvalvular AF without previous stroke, the number of patients with CHADS(2) score 1 was 422 (62.9 +/- 10.7 years old, male 290 68.7%) and their antithrombotic therapies were as follows: warfarin (n = 143), aspirin (n = 124), other antiplatelet (n = 45), and no antithrombosis (none: n = 110). We reviewed the incidences of ischemic stroke, mortality, and bleeding complications during the follow-up period. Results were: (1) during 22.3 +/- 17.8 months of follow-up, the incidence of ischemic stroke was significantly lower in warfarin (6 patients, 4.2%, mean international normalized ratio INR 2.0 +/- 0.5 IU) than in aspirin (16 patients, 12.9%, P = 0.008) than none (23 patients, 20.9%, P or=2 g/dL, requiring hospitalization or red blood cell transfusion >or=2 pints) was not different between warfarin (2.1%) and aspirin (0.8%, P = NS), but minor bleeding was more common in warfarin (10.5%) than in aspirin (2.4%, P = 0.007). CONCLUSION: In AF patients with CHADS(2) score 1, warfarin was better to prevent ischemic stroke than aspirin without increasing the incidence of major bleeding complications. However, the incidence of minor bleeding was higher in the warfarin group than the aspirin group.
Lee et al. (Tue,) conducted a cohort in Nonvalvular atrial fibrillation with CHADS2 score 1 (n=422). Warfarin vs. Aspirin was evaluated on Ischemic stroke (p=0.008). Warfarin significantly reduced the incidence of ischemic stroke compared to aspirin (4.2% vs 12.9%, P=0.008) in patients with nonvalvular atrial fibrillation and a CHADS2 score of 1.