Most women and people older than 65 years with atrial fibrillation should take anticoagulants to prevent stroke, according to an analysis of current guidelines published March 2 online ahead of print in JAMA Internal Medicine. 


In 2014, the American Heart Association, American College of Cardiology, and Heart Rhythm Society issued broader guidelines for the use of anticoagulants in treating atrial fibrillation, specifically including female sex as a contributing risk factor for stroke.

Emily O’Brien, PhD, and coauthors reviewed data on 10,132 patients with atrial fibrillation to determine how the more inclusive guidelines could affect the number of patients recommended for treatment with drugs.


The researchers found that 91% of all patients and 98% of women with atrial fibrillation would be recommended for anticoagulants, according to the new guidelines. The recommendations also lower the age, from 75 years to 65 years, at which patients are considered at risk for stroke, indicating that almost 99% of patients with atrial fibrillation older than age 65 years should be recommended for anticoagulant therapy, as compared with approximately 80% of patients with atrial fibrillation per the previous set of guidelines.


“The full adoption of the guidelines could reclassify nearly 1 million people with atrial fibrillation who previously weren’t recommended for treatment with blood thinners,” Dr. O’Brien said. Anticoagulants are associated with an increased risk for bleeding, but for most patients, the benefits outweigh the bleeding risk, she added.