Overtreatment of Low-Risk Patients With Atrial Fibrillation—The Quality Coin Has 2 Sides

To the Editor I read with interest the article by Hsu et al¹ in the April issue of JAMA Cardiology. The article highlighted that less than 50% of patients with atrial fibrillation with CHADS₂ scores exceeding 3 received oral anticoagulation therapy with warfarin or a nonvitamin K antagonist anticoagulant, even in the American College of Cardiology National Cardiovascular Data Registry Practice Innovation and Clinical Excellence Registry. While I agree with the authors that this represents an important undertreatment gap in high-risk patients, I would like to draw attention to another gap that receives far less attention. Examining Figure 2¹ illustrates a phenomenon we found in 42 834 Canadian patients with atrial fibrillation²: almost one-third of low-risk individuals with CHADS₂ or CHA₂DS₂-VASc scores of 0 received warfarin or a nonvitamin K antagonist anticoagulant. As the risks of full anticoagulation therapy exceed the potential benefits in patients at low risk for stroke, this is another example of overtreatment that deserves increased attention from researchers and policy makers.