Abstract 1248.5: Lipoprotein Changes in HIV-Infected Antiretroviral-Naïve Individuals after Starting Class-Sparing Antiretroviral Therapy: ACTG Study A5152s

Abstract

Patients with human immunodeficiency virus (HIV) receiving antiretroviral therapy (ART) are at increased risk of cardiovascular disease (CVD). In HIV-infected patients on ART, abnormalities of serum lipoproteins and insulin resistance have been associated with endothelial dysfunction. However, the effects of ART on dyslipidemia and CVD risk have been difficult to study because of the complexity of ART regimens and varying metabolic effects between and within ART classes. This study evaluated the effects of three ART regimens on lipids and lipoproteins, markers of insulin and glucose metabolism, and endothelial function. This was a substudy of A5142, a prospective, multicenter study of 82 treatment-naïve HIV-infected individuals randomly assigned to receive one of 3 class-sparing HIV treatment regimens: nucleoside reverse transcriptase inhibitors (NRTIs) + the non-nucleoside reverse transcriptase inhibitor efavirenz, NRTIs + the protease inhibitor lopinavir/ritonavir (LPV/r), or NRTI-sparing regimen of efavirenz + LPV/r. Lipoprotein particle concentrations were measured by nuclear magnetic resonance spectroscopy. Endothelial function was evaluated by brachial artery flow-mediated vasodilation (FMD) at baseline and after 24 weeks. All values are medians (interquartile range). Total and small low-density lipoprotein concentrations increased by 152 (−49, +407, p<0.01) and 130 (−98, +417, p<0.01) nmol/L, respectively, especially in the 0.04). Very low-density lipoproteins also increased (p+0.01), with larger increases in the arms that contained LPV/r (p KW 0.022). High-density lipoproteins increased by 6.0 mcmol/L (+2.8, +10.4, p<0.01), similarly in each arm. FMD increased by 1.48% (−0.20, +4.30%, p<0.001) with similar changes in each arm. Changes in lipoproteins were not related to changes in markers of insulin/glucose metabolism or FMD. Effective ART is associated with increases in total and small low-density lipoproteins and very low-density lipoproteins, especially in regimens that contain LPV/r. Over 24 weeks, the vascular effects of ART-related lipid changes may be outweighed by beneficial effects on treatment of HIV infection.