Introduction

Direct oral anticoagulants are the standard of care for venous thromboembolism (VTE) treatment. These agents are recommended regardless of patient weight and body mass index (BMI). However there remains limited evidence supporting the use of apixaban in patients with severe obesity with a BMI ≥ 40 mg/kg2 or weight ≥ 120 kg.

Objectives

The purpose of this study is to evaluate the efficacy and safety of apixaban for VTE in patients with a BMI ≥ 40 mg/kg2 or weight ≥ 120 kg.

Methods

This multi-center, retrospective study compared the use of apixaban versus warfarin in patients with severe obesity for treatment of VTE between January 1, 2012 and December 31, 2019. Patients were identified by diagnosis codes for acute VTE and a weight ≥ 120 kg or BMI ≥ 40 kg/m2. The primary efficacy outcome was time to recurrence of VTE within 12 months, and the primary safety outcome was time to major bleeding within 12 months. Secondary outcomes included incidence of recurrent VTE, major bleeding, clinically relevant non-major bleeding (CRNMB), all-cause mortality, number of total hospital encounters, and switch in anticoagulant.

Results

A total of 1099 patients were included in the study. Of these, 314 patients received apixaban and 785 received warfarin. The mean weight and BMI was 137 kg and 46 kg/m2, respectively. Time to recurrent VTE was significantly longer in those treated with apixaban compared to warfarin (p = 0.018). After controlling for confounding factors, apixaban use was associated with a reduced risk of recurrent VTE compared to warfarin (Hazard Ratio (HR) = 0.54, 95% Confidence Interval (CI): 0.29 - 0.97, p = 0.04). There were no significant differences in major bleeding, CRNMB, or all-cause mortality between groups.

Conclusion

In patients with a BMI ≥ 40 kg/m2 or weight ≥ 120 kg, apixaban appears to be effective and safe for the treatment of VTE.