Meta-analysis comparing inappropriately low dose versus standard dose of direct oral anticoagulants in patients with atrial fibrillation

BackgroundThe appropriateness of direct oral anticoagulant (DOAC) dosing has been the issue in the real-world setting, and inappropriately lower DOAC dose may not be as effective or safe as the standard dose in patients with atrial fibrillation (AF). Multiple real-world studies compared the inappropriately lower DOAC dose versus the standard dose, but their main findings were contradictory.MethodsA meta-analysis was performed to compare the efficacy and safety of the inappropriately lower DOAC dose with the standard DOAC dose in patients with AF. Database searches through May 30, 2021, were performed using Medline and Google Scholar. The primary efficacy outcome was stroke or systemic embolism, and the primary safety outcome was major bleeding. The secondary outcome was all-cause mortality.ResultsA total of 16 studies were included in this meta-analysis. It revealed that the inappropriately lower DOAC dose was significantly associated with a higher event rate of stroke or systemic embolism compared with the DOAC standard dose (odds ratio 1.21 [95% CI 1.02–1.43], P = 0.03, I2 = 66%). There was no significant difference in the major bleeding event rate between these groups (1.03, [0.92–1.15], P = 0.62; I2 = 27%).ConclusionThe inappropriately lower DOAC dose should be avoided to optimize DOAC effectiveness in patients with AF.