NOACs more effective than warfarin, safer in Asians
Regardless of dosing, nonvitamin K antagonist oral anticoagulants (NOACs) are more effective than warfarin for atrial fibrillation (AF) and safer in Asian than in non-Asian populations, a new meta-analysis shows.
Randomized controlled trials (RCTs) that compared the efficacy of any NOAC with warfarin in Asian patients with nonvalvular AF were searched from the databases of PubMed, CINAHL and CENTRAL. Only those that employed standard NOAC doses were included.
Among the information extracted were efficacy and safety outcomes, study design, sample characteristics and management details. The Cochrane Collaboration tool for detecting risk of bias was used.
After applying the selection criteria, six RCTs (n=6,496) were included in the meta-analysis. Of all the participants, 1,114 were treated with NOACs once-daily while 2,137 were treated twice-daily. The remaining 3,245 received warfarin.
Compared to dose-matched warfarin, the risk of stroke or systemic embolism was lower in Asian (risk ratio [RR], 0.74; 95 percent CI, 0.53 to 1.04) and non-Asian (RR, 0.90; 0.80 to 1.01) patients who received a once-daily dose of NOACs.
Similarly, the risk of stroke or systemic embolism in Asian (RR, 0.63; 0.47 to 0.83) and non-Asian (RR, 0.82; 0.71 to 0.94) patients was lower for twice-daily NOACs than for warfarin. None of the associations reached statistical significance, however.
On the other hand, the risk of bleeding in Asian patients (RR, 0.63; 0.47 to 0.85) was significantly lower than in non-Asian patients (RR, 0.93; 0.84 to 1.02; p=0.015) for the once-daily NOACs. Risk of bleeding from twice-daily NOACs was also significantly lower in Asian patients (RR, 0.57; 0.43 to 0.75) than in non-Asian patients (RR, 0.84; 0.77 to 0.93; p=0.007).