Standard dose versus low dose non–vitamin K antagonist oral anticoagulants in Asian patients with atrial fibrillation: A meta-analysis of contemporary randomized controlled trials

Background Although randomized controlled trials (RCTs) indicated that standard dose non–vitamin K antagonist oral anticoagulants (NOACs) were more compelling, low dose NOACs are commonly used in clinical practice in Asia. Objective The purpose of this study was to assess the relative therapeutic benefit and risk of standard dose vs low dose NOACs in Asian patients enrolled in contemporary RCTs. Methods We performed a prespecified meta-analysis of 3155 Asian patients with NOACs in the RE-LY (Randomized Evaluation of Long-Term Anticoagulation Therapy) and ENGAGE AF-TIMI 48 (Effective Anticoagulation with Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48) trials. Efficacy and safety with standard dose vs low dose NOACs were compared by risk ratios (RRs) and 95% confidence intervals (CIs) in a random-effects model. An evidence network incorporating additional Asian patients from ROCKET AF, J- ROCKET AF, and ARISTOTLE was constructed with the Bayesian method. Results Risks of stroke or systemic embolism and ischemic stroke were significantly reduced with standard dose vs low dose NOACs (RR 0.62, 95% CI 0.45–0.85; and RR 0.55, 95% CI 0.38–0.79, respectively). Rates of major, intracranial, and life-threatening bleeding with 2 dosing regimens were broadly similar (RR 1.31, 95% CI 0.74–2.33; RR 1.54, 95% CI 0.72–3.30; and RR 1.49, 95% CI 0.87–2.55, respectively). Absolute rates of all-cause mortality and the net clinical outcome with standard dose NOACs were lower but not statistically significant (absolute reduction 0.4% per year and 1.1% per year, respectively). Network meta-analyses demonstrated that standard dose NOACs had the most favorable risk–benefit profile among oral anticoagulants. Conclusion In Asian patients, standard dose NOACs represent a more appealing therapeutic option than low dose NOACs, with a significant reduction in ischemic stroke without an excess of major bleeding.