Abstract 11309: Epicardial Fat is Associated with Subclinical Coronary Atherosclerosis in the Multicenter AIDS Cohort Study (MACS)
Aims. Cytokines released by epicardial fat are implicated in the pathogenesis of atherosclerosis. We hypothesized that HIV infection is associated with increased epicardial fat and is associated with subclinical coronary atherosclerosis.
Methods. Two hundred eighty one HIV-infected and 123 HIV-uninfected homosexual men age 45 to 70 completed a non-contrast CT scan to evaluate epicardial fat volume (EV) (fat within the pericardium) and coronary artery calcium (CAC), and, if eligible, a coronary CT angiogram to measure total plaque severity score (TPS) (n = 305), a semiquantitative measure of coronary plaque burden. Logistic regression was used to evaluate the association between CAC presence and EV adjusted for age and serostatus, and median regression for association with TPS.
Results. HIV-infected men were younger and had lower BMI than seronegative men (54 ± 6 vs 57 ± 7 yrs; 26 ± 4 vs 28 ± 5 kg/m2). However, mean EV was higher in HIV-infected men (123 ± 59 vs. 113 ± 55 mm3, p < 0.005). Years of antiretroviral therapy received was positively associated with EV adjusted for age (p = 0.03). In the entire cohort, the prevalence of CAC was 53% and the median TPS was 3.0 ± 4.4. EV was positively associated with CAC presence (OR = 1.05, 95% CI, 1.01-1.09, p = 0.02) adjusted for age and HIV serostatus. EV was also positively associated with TPS derived from CT angiography (median TPS was 0.13 higher per 10 mm3 of EV, p = 0.002), adjusted for age and HIV serostatus and remained significant with BMI added (p = 0.01) or with visceral adipose volume added to the model (p = 0.03). EV was also associated with fasting insulin and triglycerides and inversely with HDL-C (all p < 0.05). The association between EV and TPS was significant with these parameters in the model. There were no interactions between HIV serostatus and associations between EV and either CAC or TPS. Similar associations were seen with pericardial fat (fat outside the pericardium) and total intrathoracic fat, but were generally of lower magnitude.
Conclusion. Epicardial fat is greater in HIV-infected men than HIV-uninfected men and is associated with duration of antiretroviral therapy. Among both HIV-infected and uninfected men, EV is associated with serum insulin and lipids, and with subclinical coronary artery atherosclerosis.
- © 2011 by American Heart Association, Inc.