CROI 2019 Abstract eBook

Abstract eBook

Poster Abstracts

815 GROWTH AND METABOLIC CHANGES AFTER ANTIRETROVIRAL START IN SOUTH AFRICAN CHILDREN Michela Masi Leone 1 , Stephen M. Arpadi 2 , Chloe A. Teasdale 2 , Katharine Yuengling 2 , Nonzwakazi Sogaula 2 , Anthony Mutiti 2 , Mary Mogashoa 3 , Emilia M. Rivadeneira 4 , Elaine J. Abrams 2 , Jennifer Jao 5 1 Icahn School of Medicine at Mt Sinai, New York, NY, USA, 2 ICAP at Columbia University, New York, NY, USA, 3 US CDC Pretoria, Pretoria, South Africa, 4 CDC, Atlanta, GA, USA, 5 Northwestern University, Chicago, IL, USA Background: High viral load (VL) associated with delays in antiretroviral therapy (ART) initiation has been linked to poor outcomes in children living with HIV (CLHIV). Fewer studies have assessed the impact of VL at initiation on growth and metabolic changes of CLHIV on optimal ART. We assessed longitudinal alterations in growth and lipid metabolism in CLHIV <12 years old initiating 1st-line ART in South Africa (SA) from 2012 to 2015. Methods: Per SA national ART guidelines, CLHIV <3 years were initiated on lopinavir/ritonavir (LPV/r)-based and those ≥3 years on efavirenz (EFV)-based ART (both regimens included abacavir+lamivudine). Length-for-Age (LAZ), Weight-for-Age (WAZ), and Body Mass Index-for-Age (BMIZ) z scores were calculated using World Health Organization reference standards. Lipids [Total Cholesterol (TC), Low-Density Lipoprotein (LDL), and High-Density Lipoprotein (HDL)] were measured at enrollment, 6, 12, and 24 months. Mixed effects models were fit to assess the association of VL at initiation with each z-score and lipid subfraction over time. Interaction terms to evaluate the effect of VL on rates of change in each outcome were dropped where p-value>0.05. CLHIV<3 years on LPV/r-based ART were analyzed separately from those ≥3 years on EFV-based ART. Results: Of 283 CLHIV, 172 <3 years started LPV/r-based ART and 111 >3 years started EFV-based ART. At enrollment, younger CLHIV on LPV/r and older CLHIV on EFV had a median age at ART start of 10 months and 8 years, log VL of 6.1 and 5.2, and CD4% of 19% and 14%, respectively. Among younger CLHIV, higher VL at ART initiation was associated with persistently lower mean differences over time in LAZ (ß:-0.32, p=0.02), WAZ (ß:-0.34, p=0.01), TC (ß:-6.65, p=0.05) and LDL (ß:-7.26, p<0.01), but was not associated with slope changes in any of the outcomes after adjustment (Table 1). Among older CLHIV, higher VL at enrollment was associated with significantly lower mean LAZ (ß:-0.27, p=0.05) and borderline significantly lower WAZ (ß:-0.32, p=0.06) as well as with more rapid increases in LAZ (ß:0.14, p=0.01) and WAZ (ß:0.19, p=0.04). No associations were found between VL and lipids among older CLHIV. Conclusion: High viral load at ART initiation was associated with persistently lower growth and lipid outcomes over time among younger CLHIV on LPV/r- based ART. Further research is needed to understand the impact of this trend in lipids on the long term cardiometabolic health of young CLHIV with high viral burden at ART initiation.

Poster Abstracts

816 LOWER BONE STRENGTH BY PERIPHERAL QUANTITATIVE CT IN CHILDREN LIVING WITH HIV

Stephanie Shiau 1 , Michael T. Yin 1 , Renate Strehlau 2 , Megan Burke 2 , Faeezah Patel 2 , Louise Kuhn 1 , Ashraf Coovadia 2 , Shane Norris 2 , Stephen M. Arpadi 1 , for the CHANGES Bone Study Team 1 Columbia University Medical Center, New York, NY, USA, 2 University of the Witwatersrand, Johannesburg, South Africa Background: Most prior studies demonstrating compromises in bone mass among children living with HIV (CLWH) used dual x-ray absorptiometry (DXA). DXA, in contrast to peripheral quantitative computed tomography (pQCT), estimates areal (2D) rather than volumetric (3D) bone mineral density (vBMD), is unable to distinguish between cortical and trabecular bone, and does not provide an estimate of bone strength. The aim of this study is to compare bone structure and strength in school-aged CLWH and controls. Methods: This study included 172 CLWH on ART and 99 controls without HIV enrolled in the CHANGES Bone Study at the Empilweni Services and Research Unit in Johannesburg, South Africa. Peripheral quantitative computed tomography (pQCT) scans (Stratec XCT-2000) of the non-dominant radius (4% slice for trabecular) and tibia (38% slice for cortical) were performed at the MRC/WITS Developmental Pathways for Health Research Unit. Measurements included trabecular area and vBMD, as well as cortical area, thickness, and vBMD. Bone strength was estimated by the polar strength strain index (SSI), a validated measure of fracture risk. Results: At the time of pQCT scan, CLWH (51%male) and controls (63%male) were an average of 10.9 and 10.2 years of age, respectively. Mean ART duration for CLWH was 9.5 years, with 121 (70.4%) on a LPV/r-based, 49 (28.5%) on an EFV-based regimen, and 2 on another regimen. The CLWH had a lower radial length (208 vs. 217 mm, p<0.01), tibial length (299 vs. 328 mm, p<0.01), trabecular area (95 vs. 112 mm^2, p<0.01), and cortical area (157 vs. 185 mm^2, p<0.01) than controls. No difference in trabecular vBMD or cortical vBMD was observed in CLWH compared to controls after adjustment for sex, age, and radial or tibial length. Polar SSI was lower in CLWH than controls (778 vs. 962 mm^3, p<0.01); this finding was consistent in boys and girls. In addition, CLWH on a LPV/r-based regimen had lower trabecular (199 vs. 220 mg/cm^3, p<0.02) and cortical vBMD (1076 vs. 1092 mg/cm^3, p=0.017) than those on an EFV-based regimen. No difference in polar SSI was observed between treatment groups. Conclusion: Reduced bone strength was observed in well-suppressed CLWH on ART, placing them at a higher risk for fracture. In addition, lower vBMD was found in CLWH on a LPV/r-based regimen compared to EFV-based regimen. Bone outcomes are an important consideration for treatment guidelines.

CROI 2019 317