Is the epicardial adipose tissue area on non-ECG gated low-dose chest CT useful for predicting coronary atherosclerosis in an asymptomatic population considered for lung cancer screening?

Objects: The purpose was to determine whether the epicardial adipose tissue (EAT) area on low-dose chest CT (LDCT) could be used to predict coronary atherosclerosis in an asymptomatic population considered for lung cancer screening. Methods: Subjects aged 55-80 years with smoking history who underwent both LDCT and coronary CT angiography (CCTA) were retrospectively enrolled. Correlation between the EAT volume in CCTA and EAT area in LDCT was evaluated. Coronary risk factors including the body surface area (BSA) indexed EAT area were compared between coronary plaque negative and positive groups. Significant factors for predicting coronary atherosclerosis were analyzed with logistic regression analysis. Receiver-operating characteristic curve analysis was performed to determine the cutoff value. Results: A total of 438 subjects were enrolled, including 299 subjects with coronary atherosclerosis. There was a good correlation between the EAT volume in CCTA and EAT area in LDCT (ρ = 0.712, p < 0.001). There were significant differences in age, systolic blood pressure, all BSA indexed EAT area, sex, and hypertension between plaque negative and positive groups. In multivariate logistic regression for the BSA indexed EAT area in LDCT at the RCA level, sex (OR: 11.168, 95% CI: 2.107-59.201, p = 0.005), systolic blood pressure (OR: 1.021, 95% CI: 1.005-1.036, p = 0.009), hypertension (OR: 1.723, 95% CI: 1.103-2.753, p = 0.017), and EAT area (OR: 1.273, 95% CI: 1.154-1.405, p < 0.001) were significant. The area under the curve of the BSA indexed EAT area in LDCT at the RCA level for coronary atherosclerosis was 0.657, and the cut-off value was 7.66 cm²/m². Conclusion: The EAT area in LDCT could be used to predict coronary atherosclerosis in an asymptomatic population considered for lung cancer screening. Key Points: • To quantify EAT, the EAT area in LDCT can be used instead of the EAT volume in CCTA. • The EAT area measured in LDCT can be used as a predictor of coronary artery disease. • The extensive CAD group tended to have a greater EAT area than the non-extensive CAD group.