Impact of BMI on clinical outcomes of NOAC therapy in daily care - Results of the prospective Dresden NOAC Registry (NCT01588119)

Abstract

Direct acting non-Vitamin K antagonist oral anticoagulants (NOAC) are characterized by a fixed dosing regimen. Despite the potential for relative underdosing due to large distribution volumes, dose adjustments for patients with high body mass index (BMI) are not recommended. Since efficacy and safety data in obese patients are scarce, we evaluated the impact of BMI on clinical outcomes in daily care patients treated with NOAC for stroke prevention in atrial fibrillation or venous thromboembolism. Using prospectively collected data from a non-interventional registry, cardiovascular (CV), major bleeding events (MB) and all-cause mortality were evaluated according to BMI classes. All outcome events were centrally adjudicated using standard scientific definitions. Between November 1st 2011 and December 31st 2016, 3432 patients were enrolled into the registry (61.3% rivaroxaban; 20% apixaban; 10.1% dabigatran, 8.6% edoxaban; mean follow-up 998.1 ± 542.9 days; median 1004 days). With increasing BMI (range 13.7-57.2 kg/m²), the proportion of patients receiving standard (vs. reduced) NOAC dose increased from 64.7% (underweight) to 78.9% (obesity). Although obese patients had more cardiovascular risk factors compared to normal weight patients, on-treatment rates of clinical outcomes (CV, MB, all-cause-mortality) were lowest in overweight and obese patients. In a large set of real-life NOAC recipients we found no indication that high BMI is associated with inferior NOAC effectiveness or safety, which is in line with recent epidemiological data of a "BMI paradox" that indicates a somewhat protective effect of higher BMI regarding unfavourable outcomes also in patients receiving fixed dose NOAC anticoagulation without dose adjustment for higher BMI.

Keywords: Anticoagulants; Bleeding; Body mass index; Cardiovascular events; Obesity.