Low-intensity warfarin (INR 1.6-2.6) yielded similar net clinical outcomes compared to standard-intensity (INR 2.0-3.0) in Asian patients with atrial fibrillation (HR 0.63; 95% CI 0.23-1.72).
RCT (n=616)
Open-label
Yes
Does low-intensity anticoagulation with warfarin reduce the composite of stroke, systemic embolism, major bleeding, and death compared to standard-intensity anticoagulation in Asian patients with atrial fibrillation?
In Asian patients with atrial fibrillation, low-intensity warfarin (INR 1.6-2.6) resulted in similar rates of stroke, major bleeding, and net clinical outcomes compared to standard-intensity warfarin (INR 2.0-3.0).
Effect estimate: HR 0.63 (95% CI 0.23-1.72)
Absolute Event Rate: 1.33% vs 2.12%
Anticoagulation with warfarin in Asian patients with atrial fibrillation (AF) often has been decreased as an international normalized ratio (INR) of prothrombin time 1.6-2.6 due to fear of bleeding, although universal criteria recommend an INR of 2.0-3.0. In this randomized, open-label trial, low-intensity anticoagulation (INR 1.6-2.6) was compared with standard-intensity anticoagulation (INR 2.0-3.0) with warfarin. A total 616 patients with AF and at least 1 risk factor for stroke were randomized to low-intensity anticoagulation (n = 308) and standard-intensity anticoagulation (n = 308) groups. The intention-to-treat analysis was performed to determine differences. The baseline characteristics of the two groups were comparable. New-onset stroke occurred in 2 patients (0.44% per year) in the low-intensity group and 5 patients (1.05% per year) in the standard-intensity group (HR 0.42, 95% CI 0.08-2.15). Major bleeding occurred in 4 patients (0.89% per year) in the low-intensity group and 5 patients (1.06% per year) in the standard-intensity group (HR 0.84, 95% CI 0.22-3.11). The rate of the net clinical outcome (composite of stroke, systemic embolism, major bleeding, and death) was 1.33% per year in the low-intensity group compared with 2.12% per year in the standard-intensity group (HR 0.63, 95% CI 0.23-1.72). In Asian patients with AF, clinical outcomes were not different between low-intensity and standard-intensity anticoagulation with warfarin.
Cho et al. (Sun,) conducted a rct in Atrial fibrillation (n=616). Low-intensity warfarin vs. Standard-intensity warfarin (Target INR 2.0-3.0) was evaluated on Net clinical outcome (composite of stroke, systemic embolism, major bleeding, and death) (HR 0.63, 95% CI 0.23-1.72). Low-intensity warfarin (INR 1.6-2.6) yielded similar net clinical outcomes compared to standard-intensity (INR 2.0-3.0) in Asian patients with atrial fibrillation (HR 0.63; 95% CI 0.23-1.72).