Non-Vitamin K Antagonist Oral Anticoagulants for Stroke Prevention in Asian Patients With Nonvalvular Atrial Fibrillation: Meta-Analysis

Background and purpose: The use of vitamin K antagonists (VKAs), the cornerstone treatment for stroke prevention in patients with atrial fibrillation, is limited by the perceived risk of serious bleeding in Asia. Non-VKA oral anticoagulants (NOACs) are safer alternatives. Here, we evaluate performance differences of NOACs between Asians and non-Asians.

Methods: We compared efficacy and safety of NOACs between patients enrolled in Asian and non-Asian countries using aggregative data from phase III clinical trials. The odds ratios (ORs [95% confidence interval]) were calculated by a random effects model.

Results: Comparing with VKAs, standard-dose NOACs reduced stroke or systemic embolism (OR=0.65 [0.52-0.83] versus 0.85 [0.77-0.93], P interaction= 0.045) more in Asians than in non-Asians and were safer in Asians than in non-Asians about major bleeding (OR=0.57 [0.44-0.74] versus 0.89 [0.76-1.04], P interaction=0.004), hemorrhagic stroke (OR=0.32 [0.19-0.52] versus 0.56 [0.44-0.70], P interaction=0.046) in particular, whereas gastrointestinal bleeding was significantly increased in non-Asians (OR=0.79 [0.48-1.32] versus 1.44 [1.12-1.85], P interaction=0.041). Generally, low-dose NOACs were safer than VKAs without heterogeneity in efficacy and safety between Asians and non-Asians, except for ischemic stroke, major, and gastrointestinal bleeding.

Conclusions: Our findings suggest that standard-dose NOACs were more effective and safer in Asians than in non-Asians, whereas low-dose NOACs performed similarly in both populations.