Association Between Atrial Fibrillation Burden and Ischemic Stroke Incidence: A Case‐Control Study on the CABANA Trial

BACKGROUND: The relationship between the burden of atrial fibrillation (AF) and the risk of ischemic stroke is crucial yet complex. This study examines this relationship to enhance stroke prediction in patients with AF. METHODS: The CABANA trial study from 2009 to 2016 analyzed the relationship between AF load, stroke, and anticoagulation. We matched age, gender, and race, as well as the control and case groups, at 1:4. Non-invasive electrocardiogram monitoring recorded load events and included the total cumulative load in the calculation. Next, we compared the net load between the stroke and control groups, and the relationship between net AF load and stroke was analyzed using univariate and multivariate logistic regression. This study also explored the interplay between stroke, AF load, and anticoagulation. RESULTS: The first independent predictor of ischemic stroke risk is the net AF load (OR = 8.72, 95% CI: 3.11-24.4, p < 0.001). Stratified by the CHA2DS2VASc score, no significant change in net AF load between the high-risk and low-risk groups was observed (p = 0.96). Finally, we categorized all patients into adequate and inadequate anticoagulation groups based on whether they received adequate anticoagulation. The net AF load in the adequate anticoagulation group was higher than in the inadequate anticoagulation group (p < 0.001). CONCLUSION: AF burden is significantly associated with the risk of ischemic stroke. Determining the threshold of AF burden can improve stroke prevention strategies, indicating the need for targeted research on risk stratification and management of patients with AF.