New drugs offer alternative to warfarin for treating stroke

Move over, warfarin. There may safer, more effective anticoagulants available to patients.

For decades, warfarin was the only reliable drug therapy for stroke prevention in individuals with atrial fibrillation. But because it blocks the body’s ability to recycle vitamin K, patients must avoid foods and drugs rich in that vitamin while also submitting to blood tests to regulate dosage. Studies show that up to 30 percent of patients currently on warfarin will stop taking it.

In a study published in CHEST Journal, Mayo Clinic cardiologist Peter Noseworthy, MD, compared the effectiveness and safety of three of warfarin’s main competitors: dabigatran, rivaroxaban and apixaban.

"We have strong data from large randomized clinical trials which demonstrate that the new medications are at least as good as warfarin in preventing stroke in atrial fibrillation," Noseworthy said in a statement. "Instead, we have performed an analysis of patients currently taking these medications in order to observe stroke and bleeding rates and make a comparison based on real-world clinical practice."

Looking at medical claims data from October 2010 through February 2015, researchers compared three one-to-one matched cohorts of patients with non-valvular atrial fibrillation. The cohorts included 31,574 patients taking either rivaroxaban or dabigatran, 13,084 patients using apixaban or dabigatran and 13,130 patients taking apixaban or rivaroxaban.

Effectiveness was determined by whether patients suffered stroke or systemic embolism. Safety was determined by whether they had a major bleeding episode while on the treatment.

Patients taking apixaban were less likely to experience major bleeding than those taking dabigatran or rivaroxaban. Rivaroxaban also had a higher risk of major bleeding and intracranial bleeding, compared to dabigatran.

While the results are informative, Noseworthy maintains that individual treatment decisions are still in the hands of the physician and that patients should never stop taking an anticoagulant without first talking to their doctor.