Prescribing Pattern of Oral Anticoagulants in Patients With Obesity

There is limited efficacy and safety data for direct oral anticoagulants (DOACs) in patients with obesity, and it has been suggested to avoid DOACs in this patient population.

Describe the prescribing pattern of oral anticoagulants in obese patients in an urban university setting and assess efficacy, safety, and adherence.

Retrospective, cohort study in patients ≥18 years with a history of VTE and/or atrial fibrillation. Patients with a BMI >40 kg/m² and/or weight >120 kilograms and a prescription for warfarin or a DOAC from August 25, 2014 until August 25, 2017 are included. The primary outcome is the number of warfarin or DOAC prescriptions. Secondary outcomes include thromboembolism and bleeding events. Patient adherence was evaluated using time in therapeutic range (TTR), adherence rate to clinic appointments, and medication possession ratio (MPR).

Of the 276 patients who met eligibility criteria, 158 (57.2%) were prescribed warfarin and 118 (42.8%) were prescribed a DOAC. There was no difference in the rate of stroke or recurrent VTE between groups (3.2% vs. 3.4%, p = 0.944). There was also no difference in the rate of bleeding between groups (16.1% vs. 17.8%, p = 0.707). The TTR for the warfarin group was 44.8 ± 23%, and appointment adherence was 78.6 ± 20%. The MPR for the DOAC group was 0.93 ± 0.24.

Despite limited data in obese patients, DOACs are prescribed in this population. Results suggest no difference in safety and efficacy compared to warfarin, but barriers to quality anticoagulation may exist in this population.