Efficacy and safety of direct oral anticoagulant in morbidly obese patients with atrial fibrillation: systematic review and meta-analysis

Aims We conducted a systematic review and meta-analysis on three outcomes. We assessed the efficacy and safety of direct oral anticoagulants (DOAC) compared to vitamin K antagonists (VKA) in morbidly obese patients with atrial fibrillation (AF). We compared the efficacy and safety of DOAC in obese patients and non-obese patients with AF. Finally, we updated the current knowledge of outcomes of AF patients with obesity compared with normal-weight patients regardless of anticoagulation type. Methods and results Using PubMed and Embase, we searched for literature published from inception to August 2020 for studies conducted in morbidly obese patients with AF who used DOACs and/or VKA for stroke or systemic embolism (stroke/SE) prevention that report efficacy and/or safety data. GRADE assessment was performed to determine the quality of the meta-analysis results. Direct oral anticoagulant was not statistically different from VKA in reducing stroke/SE with relative risk (RR) of 0.85 [95% confidence interval (CI): 0.56-1.29; very low certainty evidence]. Major bleeding risk was lower in the DOAC groups with RR of 0.62 (95% CI: 0.48-0.80; low certainty evidence). Obese patients with AF who used DOACs had lower risk of stroke/SE and similar major bleeding risk compared to non-obese patients with RR of 0.77 (95% CI: 0.70-0.84; low certainty evidence) and 1.02 (95% CI: 0.94-1.09; low certainty evidence), respectively. Obese patients with AF who used any type of anticoagulant had lower risk of stroke/SE compared to normal-weight patients with RR of 0.62 (95% CI: 0.57-0.69; low certainty evidence). Conclusion The use of DOACs in morbidly obese patients may be reasonable if needed, and more dedicated studies are needed to make a more robust recommendation.