Direct oral anticoagulants (DOACs) are preferred over warfarin for the treatment of venous thromboembolism (VTE) as well as atrial fibrillation (AF). The efficacy and safety of fixed dose regimen of DOACs remains unclear in morbidly obese patient population and are currently not recommended for use in patients with a body mass index (BMI) > 40 kg/m or a weight of >120 kg.
The goal of this study is to evaluate the use of DOACs in morbidly obese veteran population as compared to warfarin.
This retrospective single center cohort study included morbidly obese patients weighing >120 kg or BMI > 40 kg/m who were prescribed DOACs or warfarin for AF or VTE between January 1st, 2015 to May 31st, 2018. Data was extracted from the computerized patient record system (CPRS) and the Salem Veterans Affairs Medical Center (SVAMC) data warehouse. The primary outcome was combined incidence of stroke/transient ischemic attack (TIA) and VTE. Secondary outcomes included all-cause mortality, ISTH major bleed and clinically relevant non major bleed as well as primary outcome and ISTH major bleeding analyses in the subgroups of AF and VTE patients.
The study included 190 patients in warfarin group and 214 in DOACs group. Baseline characteristics were mostly well matched except for the follow up duration which was significantly longer in the warfarin group as compared to DOAC (p > 0.001). The annual incidence rate of primary outcome was similar between warfarin and DOACs (3.91% vs.1.61%; RR:2.436; 95% CI 0.85-8.54; p = 0.1543).
This hypothesis generating study suggests that DOAC use may be feasible in morbidly obese patients. Additional studies are necessary to confirm this finding and further guide clinical practice in this area.

Published by Elsevier Ltd.

Author