Background:  Whether HIV infection contributes to atherosclerosis is controversial. We investigated the relationship between HIV infection, ART, cardiovascular risk factors, and common carotid intima-media thickness (IMT) in ART-treated HIV-infected adolescents.

Methods:  In this cross-sectional study of 23 HIV⁺ adolescents and 19 age-, sex- and body mass index (BMI) -matched healthy controls, we measured:  left and right IMT; CD36 expression on monocytes; cobalamin, folic acid, homocysteine, glucose, and insulin levels; homeostatic model assessment (HOMA) index; total, high-density and low-density lipoprotein (HDL and LDL) cholesterol; triglycerides; blood pressure; and waist circumference. Groups were compared using unpaired t tests. Bootstrapped multiple linear regression was used to identify predictors of log-transformed IMT.

Results:  In the pooled sample (52% males), age ranged between 17 and 23 years, and BMI between 16.0 and 25.6 kg/m². At the time of the study, 18 (78%) and 5 (22%) cases were receiving 2 NRTI+1 NNRTI or 2 NRTI+1 PI, respectively. Previously 21 of the 23 (91%) cases were ever exposed to NRTI+PI, 11 (48%) cases were ever exposed to 1or 2 NRTI, and 2 cases were naïve to ART. HIV⁺ adolescents were receiving ART from a median time of 10.4 (range 1.1 to 20.8) years. Mean (SD) duration of each regimen was: 2.2 (2.8) years for NRTI, 6.1 (2.9) years for NRTI+PI, 2.5 (1.7) years for NRTI+NNRTI. Left and right IMT were highly concordant in both HIV⁺ patients and healthy controls (concordance coefficient ≥0.90, p <0.001). Mean (SD) IMT was higher in HIV⁺ than in controls (0.5 [0.1] mm vs 0.4 [0.1] mm, p <0.001)]. Moreover, as compared to controls, HIV⁺ subjects expressed more CD36 on monocytes (p = 0.002), and less HDL cholesterol (p = 0.016) and folic acid (p <0.001); there were no differences for the other variables. Among all the variables of interest, the only predictors of log-transformed IMT identified at bootstrap analysis were HIV infection (p <0.001), male gender (p <0.001), and cobalamin level (p <0.05). These predictors explained 60% of IMT variance.

Conclusions:  Long-term HIV infection in adolescents is a risk factor for increased IMT. This adverse structural change is also associated to male gender and lower vitamin B12 levels. On the contrary, no additional detrimental effects were observed after a median of 10.4 years of ART.