Association between Carotid Intima-Media Thickness and Pericardial Fat in the Multi-Ethnic Study of Atherosclerosis (MESA)

Introduction: Carotid intima-media thickness (IMT) is a subclinical marker of atherosclerosis and a strong predictor of stroke. Pericardial fat (PF), the fat depot around the heart, has been associated with several atherosclerosis risk factors. We sought to examine the association between carotid IMT and PF, and to examine whether such an association is independent from common atherosclerosis risk factors including measures of overall adiposity. Methods: Unadjusted and multivariable-adjusted linear regression analysis was used to examine associations between common carotid artery (CCA) IMT and internal carotid artery (ICA) IMT with PF in a random sample of 996 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) who underwent carotid ultrasound and chest computed tomography at baseline examination. Results: A significant positive correlation was observed between PF and CCA-IMT (r = 0.27, P < .0001) and ICA-IMT (r = 0.17, P < .0001). In an unadjusted sex-specific linear regression analysis, there was a significant association between PF (1-SD difference) and CCA-IMT (mm) in both women (beta coefficient [95% confidence interval]: 0.06 [0.04, 0.08], P < .0001) and men (0.03 [0.01, 0.05], P < .0002), an association that persisted after further adjusting for age and ethnicity (0.02 [+0.00, 0.04], P = .0120 for women, and 0.02 [+0.00, 0.03], P = .0208 for men). However, after additional adjustment for atherosclerosis risk factors and either body mass index or waist circumference, these relations were no longer significant in either sex. In similar analyses, PF was significantly associated with ICA-IMT in both men (0.11 [0.06, 0.15], P < .0001) and women (0.08 [0.02, 0.13], P = .0041). These relations were no longer significant in women in multivariable-adjusted models, but persisted in men in all models except after adjusting for age, ethnicity, and waist circumference. Conclusions: In the general population PF is associated with carotid IMT, an association that possibly is not independent from markers of overall adiposity or common atherosclerosis risk factors.