Epicardial fat thickness is associated with reduced vertebral artery flow in healthy adults

Epicardial fat tissue is increasingly recognized as a metabolically active adipose compartment linked to vascular inflammation and endothelial dysfunction. While links between EFT and coronary or carotid disease have been widely reported, data on its relationship with cerebrovascular hemodynamics remain limited. This study examined the association between epicardial fat thickness and vertebral artery blood flow in healthy individuals, with particular attention to potential side-specific differences. This cross-sectional study included 98 healthy adults. Epicardial fat thickness was measured using transthoracic echocardiography. Right and left vertebral artery flow volumes were assessed by color Doppler ultrasonography. Associations between EFT and vertebral artery flow were analyzed using Pearson correlation. Multivariable linear regression identified independent determinants of left vertebral artery flow volume (LVAF). ROC analysis was used to assess whether EFT could identify low LVAF. Epicardial fat thickness was not significantly associated with right vertebral artery flow volume (r = − 0.155, p = 0.127). In contrast, a significant inverse relationship was observed between EFT and LVAF (r = − 0.359, p < 0.001). In adjusted analyses accounting for age, sex, body size, smoking status, and vertebral artery diameter, EFT remained the only independent negative predictor of LVAF (β = −8.14, p = 0.001). Participants with higher EFT values (≥ 5.0 mm) exhibited significantly lower LVAF compared with those with lower EFT values. ROC analysis demonstrated modest discriminative performance for low LVAF (AUC = 0.65). Epicardial fat thickness was independently associated with reduced left vertebral artery flow. These findings suggest a potential link with altered cerebrovascular hemodynamics, although larger prospective studies are needed to confirm this association.