National Trends in Ambulatory Oral Anticoagulant Use

Geoffrey D. Barnes, Eleanor Lucas, G. Caleb Alexander, Zachary D. Goldberger

Four direct oral anticoagulants (DOACs) have been brought to market for the treatment of nonvalvular atrial fibrillation and venous thromboembolism. Many forces, including numerous positive trial results, emerging safety concerns, marketing and promotion may shape DOAC adoption by providers. However, relatively little is known regarding their ambulatory utilization compared with warfarin, as well as the degree to which they have decreased undertreatment of atrial fibrillation. We used the IMS Health National Disease and Therapeutic Index, a nationally representative audit of outpatient office visits, to estimate the use of warfarin and DOACs between 2009 and 2014. Overall, visits with anticoagulation use increased from 2.05 (95% CI 1.82-2.27) to 2.83 (95% CI 2.49-3.17) million (M) quarterly visits (p<0.001). Of these, DOAC use has grown to 4.21M (95% CI 3.63M-4.79M; 38.2% of total) treatment visits in 2014 since their introduction in 2010. Use of all oral anticoagulants in treatment visits for atrial fibrillation has increased from 0.88M (95% CI 0.74M-1.02M) to 1.72M (95% CI 1.47M -1.97M; p<0.001), with similar DOAC and warfarin use in 2014. Atrial Fibrillation visits with anticoagulant use increased from 51.9% (95% CI 50.4%-53.8%) to 66.9% (95% CI 65.0%-69.3%) between 2009 and 2014 (p<0.001). In 2014, rivaroxaban was the most commonly prescribed DOAC for atrial fibrillation (47.9% of office visits), followed by apixaban (26.5%) and dabigatran (25.5%). DOACs have been rapidly adopted, matching the use of warfarin, and are associated with increased use of oral anticoagulation for patients with atrial fibrillation.