Visceral adipose tissue and carotid intima-media thickness in HIV-infected patients undergoing cART: a prospective cohort study

Background: Combined antiretroviral therapy (cART) in HIV-infected patients has been associated with lipodystrophy, metabolic abnormalities, and an increased risk of cardiovascular disease. Ultrasound measures of carotid artery intima-media thickness (cIMT) have been used as a valid measure of subclinical atherosclerosis and as a tool to predict the risk of cardiovascular events. Our aim was to evaluate the progression of cIMT in HIV-infected patients subjected to cART, with and without lipodystrophy, over a one-year period. Methods: We performed a one-year prospective cohort study to compare changes in cIMT, metabolic and inflammation markers in HIV-infected patients undergoing cART. Body composition was assessed by dual-energy Xray absorptiometry (DXA) and abdominal computed tomography (CT). Levels of blood pressure, lipids and inflammatory markers were evaluated, as well as ultrasound measures of cIMT. Lipodystrophy defined by Fat Mass Ratio (L-FMR) is measured as the ratio of the percentage of trunk fat mass to the percentage of lower limb fat mass by DXA. Categorical variables were compared, using the chi-square or Fisher's exact test. Wilcoxon ranks tests and the McNemar chi-square tests were used to compare results of selected variables, from the first to the second year of evaluation. Means of cIMT, adjusted for age, glucose, triglycerides levels, systolic blood pressure (SBP), and waist to hip ratio were calculated, using generalised linear models for repeated measures. Results: L-FMR was present in 44.3% of patients, and the mean of cIMT increased significantly in this group [0.82 (0.26) vs 0.92 (0.33); p = 0.037], as well as in patients without lipodystrophy [0.73 (0.20) vs 0.84 (0.30); p = 0.012]. In the overall sample, the progression of cIMT was statistically significant after the adjustment for age, glucose, triglycerides, and SBP, but the significance of the progression ceased after the adjustment for waist/hip ratio [0.770 (0.737-0.803) vs 0.874 (0.815-0.933); p = 0.514]. Conclusions: Carotid IMT progressed significantly in both groups of this HIV-infected cohort, however no association between the progression of cIMT and the presence of lipodystrophy defined by FMR was found. Visceral adipose tissue had an impact on the increment of cIMT, both in patients with, and without lipodystrophy defined by FMR.