Epicardial Adipose Tissue Volume and Left Atrial Remodeling: A J-Shaped Association in Older Adults

Background: Previous studies identified epicardial adipose tissue (EAT) as a metabolic risk factor for atrial remodeling. However, given the distinct physiological changes associated with aging, findings from the general population may not translate directly to older adults. This study aims to clarify the relationship between EAT and left atrial (LA) diameter in older adults specifically. Methods: This retrospective cross-sectional study was conducted among in an older adult cohort (aged ≥ 65 years) at Peking Union Medical College Hospital. The association between EAT and LA diameter was evaluated using multivariable linear regression, a generalized additive model, and restricted cubic spline (RCS) modeling. Results: Among 353 participants (median age 75 years), EAT was independently associated with LA diameter (β = 0.286, p < 0.001) after adjusting for confounders including age, BMI, and LDL-C. Notably, RCS analysis revealed a J-shaped relationship between EAT volume and LA dimensions. Specifically, when EAT exceeded 110.7 cm3, the LA diameter increased significantly by 0.22 mm per 10 cm3 increase in EAT (p = 0.004). Conclusions: EAT accumulation shows a non-linear association with left atrial remodeling in older adults, with an identifiable threshold at 110.7 cm3. EAT may be a valuable biomarker for cardiovascular risk stratification, suggesting that EAT burden monitoring could be beneficial in older populations.