Does combining aspirin and warfarin decrease the risk of stroke for patients with nonvalvular atrial fibrillation?

Abstract

Adjusted-dose warfarin (international normalized ratio [INR]=2.0-3.0) remains the most efficacious antithrombotic regimen for the primary and secondary prevention of cardioembolic stroke in high-risk patients with nonvalvular atrial fibrillation (NVAF) (strength of recommendation [SOR]: A, based on randomized controlled trials). Aspirin therapy at a dose of 75 to 325 mg reduces the risk of stroke to a lesser degree and may be useful for low-risk patients with NVAF or patients at high risk for bleeding (SOR: A, based on randomized controlled trials). Combination therapy with low, fixed-dose warfarin (1-2 mg) and aspirin has not been shown to be superior to aspirin therapy alone. Moreover, this combination appears to be inferior to adjusted-dose warfarin (SOR: A, based on randomized controlled trials). To date, no clinical trials have investigated the efficacy and safety of combining adjusted-dose warfarin and aspirin for the prevention of stroke from NVAF.