National trends in ambulatory oral anticoagulant use

Background 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 under-treatment of atrial fibrillation. Methods 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. Results Overall, visits with anticoagulation use increased from 2.05 (95% confidence interval [CI], 1.82-2.27) to 2.83 (95% CI, 2.49-3.17) million (M) quarterly visits (P <.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 <.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 <.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%). Conclusions Direct oral anticoagulants have been adopted rapidly, matching the use of warfarin, and are associated with increased use of oral anticoagulation for patients with atrial fibrillation.