Absorption of apixaban following metabolic bariatric surgery: is reluctance still warranted?

Absorption of apixaban, a direct oral anticoagulant (DOAC), may be impaired after metabolic and bariatric surgery (MBS). The Dutch guideline advises to switch to vitamin K antagonists (VKA), while patients prefer the use of DOACs. Apixaban is not regularly prescribed after MBS due to a lack of evidence regarding its efficacy and safety. Therefore, this study aimed to evaluate the efficacy and safety of apixaban after MBS. In this retrospective cohort study, chronic DOAC users who received pre and postoperative consultation and used apixaban (5 mg twice daily) after MBS with available anti-Xa levels were included. The outcomes were: incidence rate of postoperative bleeding and thromboembolic events, number of patients switching to VKA, and percentage of anti-Xa peak levels within the expected on-therapy range up to one year postoperative. Of the 97 included patients, 63.9% were female, median age was 57 years [51-61], and preoperative BMI 43.2 kg/m2 [39.5-46.8], DOAC was mostly indicated because of atrial fibrillation (59.8%), and 71.1% underwent Roux-en-Y gastric bypass. No thromboembolic events or major bleeds occurred and one clinically relevant non-major bleeding was observed (incidence rate 0.61(95% CI: 0.02-3.38) per 100 patient-years). One patient switched to VKA, and 91.1% of patients had postoperative anti-Xa peak levels within expected on-therapy range. In this population of chronic DOAC users, apixaban with consultation including regular anti-Xa peak level measurements seems safe and effective after MBS. However, future prospective research in a larger population with longer follow-up, is needed to confirm these results.