Abstract 18463: Direct Oral Anticoagulants versus Vitamin K Antagonists in Morbidly Obese Patients (BMI ≥ 40): An Updated Systematic Review and Meta-Analysis

Introduction: The safety and efficacy of direct oral anticoagulants (DOACs) compared to vitamin K antagonists (VKAs) remain unknown in patients with BMI ≥ 40 kg/m ² . We aim to evaluate the risk of recurrent VTE and major bleeding in patients with a BMI ≥ 40 when started on DOACs versus VKAs.

Methods: We conducted a systematic literature search according to PRISMA guidelines to identify studies using the terms: “venous thromboembolism”, “Vitamin K antagonists” and “direct oral anticoagulants”. After the screening, We extracted the data till May 2023 in a data extraction sheet. Our inclusion criteria were: adult patients, morbidly obese (BMI ≥ 40 kg/m ² ), who were on DOACs or VKAs for VTE or atrial fibrillation. We used a variance-weighted random-effects model to analyze data on DOACs vs. VKAs, estimating event rates and odds ratios while assessing heterogeneity. Data were analyzed using the ‘meta’ package in R.

Results: Our analysis included a total of 16 studies (n= 62704 patients). Obese patients on DOACs had a significant reduction in the risk of recurrent VTEs compared to VKAs OR 0.72 (95% CI: 0.59 - 0.88, I2 :19%). Also, DOACs were associated with a lower risk of major bleeding compared to VKAs in morbidly obese patients (OR = 0.65, 95% CI: 0.58 - 0.74, I2 :0%). For non-major bleeding, although the statistical significance was not reached, a consistent trend favoring DOACs was observed (OR = 0.76, 95% CI: 0.47-1.21). (Figure1)

Conclusions: Among morbidly obese patients (BMI ≥ 40), DOACs are associated with a significantly lower risk of recurrent VTEs, and major bleeding compared to VKA. For non-major bleeding, there was a trend favoring DOACs over VKA. Increased recruitment of obese patients in clinical trials is needed to provide us with robust data for informed clinical decision-making.