Left atrial size modify the association between uric acid and atrial fibrillation in patients with coronary artery disease

Background and aims The potential influence of left atrial size on the relationship between uric acid and atrial fibrillation has not been fully investigated. This study aims to evaluate the interaction effect of left atrial size on the association between uric acid and atrial fibrillation in patients with coronary artery disease. Methods and results This retrospective cohort study, conducted from January 2018 to October 2022, included 2004 patients undergoing Drug-Eluting Stent implantation for coronary artery disease. Utilizing logistic regression models with the product of left atrial enlargement (LAE) and uric acid, interaction effects were assessed. Among the participants, 383 had LAE, and 159 experienced atrial fibrillation. After adjusting for covariates, continuous uric acid levels were associated with an increased risk of atrial fibrillation in patients without LAE (OR:1.631, 95% CI: 1.284-2.072), but not in those with LAE (OR:1.069, 95% CI: 0.848-1.348). A significant interaction of uric acid levels was observed between groups with and without LAE (p=0.046). Restricted cubic spline curves indicated a J-shaped relationship between uric acid and atrial fibrillation in the absence of LAE. However, the association between uric acid levels and atrial fibrillation in the LAE group remained unchanged with increasing uric acid levels. Conclusion The study suggested that left atrial size modified the association between uric acid and atrial fibrillation in patients with coronary artery disease. Uric acid serves as a potential biomarker for atrial fibrillation risk, especially in individuals without LAE.