Safety and Efficacy of Direct Oral Anticoagulants Compared to Warfarin in Patients with Venous Thromboembolism and Morbid Obesity

Introduction: Several guidelines recommend using direct oral anticoagulants (DOACs) over warfarin for the prevention of venous thromboembolism (VTE), except in cases of morbid obesity. The use of DAOCs in patients with morbid obesity has not been thoroughly evaluated due to lack of representation in large clinical trials. To address this knowledge gap, we conducted a systematic review and meta-analysis of existing literature to determine the efficacy and safety of DOACs in patients with morbid obesity. Materials and Methods: A systematic review of studies comparing DOACs with warfarin in patients with morbid obesity and diagnosed with acute VTE was conducted using electronic literature searches up to December 2021. Efficacy and safety were defined as the rate of recurrent VTE and major bleeding, respectively. Results: A total of 30 822 patients were included across 13 studies. Recurrent VTE events were observed in 713 of 12 945 patients treated with DOACs, compared to 966 of 17 877 patients treated with warfarin (OR, 0.70; 95% CI, 0.50-0.99; P=0.04; I2=69%). Major bleeding events occurred in 195 of 12 675 patients on DOACs and in 386 of 17 572 patients on warfarin (OR, 0.69; 95% CI, 0.58-0.82; P<0.0001; I2=0%). Similar findings were noted for two specific DOACS, apixaban and rivaroxaban, when evaluated individually against warfarin. Conclusion: Our meta-analysis indicated that DOACs are both safe and effective in preventing VTE in patients with morbid obesity. DAOCs resulted in comparable outcomes to those seen in warfarin use. This analysis consolidates extensive observational data from a large patient cohort, thereby enhancing the evidence base for the use of DOACs in patients with morbid obesity.