Direct Oral Anticoagulants Gain Wide Acceptance, Especially for Patients with Atrial Fibrillation

New research suggests that the relative ease of using novel oral anticoagulants may be spurring more patients with atrial fibrillation (AF) to try anticoagulation and stick with it.

A study team used data from the IMS Health National Disease and Therapeutic Index to estimate usage of both warfarin and the newer class of drugs between 2009 and 2014 and to see if the 2010 introduction of the next-generation medications was associated with an increase in total anticoagulation of AF patients. Results appeared in The American Journal of Medicine.

Use of warfarin fell during the study period, but the number of American AF patients using novel oral anticoagulants grew from 0 to about 4.21 million (95% confidence interval[CI], 3.63 million - 4.79 million). Use of the newer drugs and warfarin were drawing close to parity by 2014 (43% vs. 57%), and sales of the newer drugs keep soaring. Total prescriptions tripled between 2013 and 2014.

The most popular of the novel oral anticoagulants in 2014 was rivaroxaban (Xarelto), which accounted for 47.9% of outpatient prescriptions, followed by apixaban (Eliquis) and dabigatran (Pradaxa), which accounted for 26.5% and 25.5% of outpatient prescriptions, respectively.

What’s more, the speedy embrace of the new medications was associated with an increase in overall anticoagulation. Total quarterly physician visits resulting in anticoagulation use increased from a baseline level of 2.05 million (95% CI, 1.82 million - 2.27 million) to 2.83 million (95% CI 2.49 million -3.17 million) at the end of the study period (p<0.001).

Part of that increase likely stems from the increasing number of Americans with AF, but part of it clearly stems from increasing usage of anticoagulants. At baseline, an estimated 51.9% of patients who visited a doctor for AF received anticoagulation (95% CI, 50.4%-53.8%). By the end of the study period, that figure had risen to 66.9% (95% CI, 65.0%-69.3%).

“The data provides a promising outlook about atrial fibrillation, which is known for being undertreated,” said lead study author Geoffrey Barnes, MD, MSc, a cardiologist at the University of Michigan Health System and researcher at the Institute for Healthcare Policy and Innovation. “When we don’t treat atrial fibrillation, patients are at risk for stroke. By seeking treatment, patients set themselves up for better outcomes.”

The first novel oral anticoagulant, rivaroxaban, was approved for use in 2010 and 3 others have reached the market since then. Neither trials of the new medications nor follow-up studies on real-world patients have found them to be dramatically more effective than proper doses of warfarin. However, they are generally associated with fewer adverse events, and they eliminate the need for constant blood tests and periodic dosing adjustments.

Advocates of the newer medications (including the companies that make them) argued that these advantages would lead to an increase in anticoagulation usage among AF patients, both by increasing the number of patients who begin on medication and increasing compliance among patients who receive prescriptions.

Quarterly reports from the companies that make the new drugs had already shown strong sales, but the authors of the new study believe they are the first to show that the introduction of the new anticoagulants is significantly associated with an increase in total anticoagulation usage among AF patients.