Weight change modulates epicardial fat burden: A 4-year serial study with non-contrast computed tomography

Introduction: Epicardial fat volume (EFV) is linked to cardiovascular event risk. We aimed to investigate the relationships between EFV and weight change. Methods: From the EISNER (Early Identification of Subclinical Atherosclerosis using Non-invasive Imaging Research) Registry with baseline and follow-up coronary calcium scans (1248 subjects), we selected a cohort of 374 asymptomatic subjects matched using age decade, gender and coronary calcium score (CCS) as a measure of subclinical cardiovascular risk, who underwent 2 scans at an interval of 4.1 ± 0.4 years. Using semi-automated validated software, pericardial contours were generated on all slices by spline interpolation from 5 to 10 control points. EFV was computed as fat volume within the pericardial contours. Weight gain/loss was defined as >5% change. Results: At baseline, EFV was moderately correlated to weight, body mass index (BMI) and waist circumference (r= 0.51, 0.41 and 0.50, p< 0.0001). EFV change was weakly correlated to change in weight (r= 0.37, p< 0.0001), BMI (r= 0.39, p< 0.0001) and waist circumference (r= 0.21, p= 0.002). On multivariable linear regression analysis, weight change [. β= 1.2, 95% confidence interval (CI) 0.9-1.5, p< 0.001], BMI change (β= 1.2, 95% CI 0.9-1.5, p< 0.001), gender (β= -6.4, 95% CI -10.9 to -1.8, p= 0.006) and hypertension (β= 4.7, 95% CI 0.5-9.0, p= 0.03) predicted EFV change. EFV decreased in 54 subjects with weight loss and increased in 71 subjects with weight gain (-2.3 ± 21.1% vs. 23.3 ± 24.4%, p< 0.001). Conclusions: EFV is related to body weight, BMI and waist circumference. Reduction in weight may stabilize or reduce EFV, while weight gain may promote EFV increase.