CROI 2020 Abstract eBook

Abstract eBook

Poster Abstracts

Background: Poor linear growth (i.e. stunting), is common in perinatally- acquired HIV infection, yet effects of HIV on adolescent musculoskeletal development remain poorly characterized in sub-Saharan Africa. We hypothesize that bone and muscle growth in children living with HIV (CWH) are impaired, putting them at risk of low bone mass and functional disability, which may increase future fracture risk. We aimed to determine the impact of HIV on size-adjusted (important in context of small stature) bone density and muscle function in peri-pubertal children in Zimbabwe. Methods: CWH aged 8-16 years, established on ART for ≥2 years, from two public sector HIV clinics and sex and aged-band frequency-matched uninfected children from schools were recruited. Musculoskeletal assessments included grip strength, standing long jump and dual-energy X-ray absorptiometry (DXA). Total-body less-head (TBLH) bone mineral content (BMC) for lean mass adjusted for height (TBLH BMCLBM) and lumbar spine bone mineral apparent density (LS BMAD) values and Z-Scores were calculated. Differences by HIV status, and risk factors for impaired musculoskeletal measures, were determined using linear and logistic regression. Results: A total of 284 CWH and 222 children without HIV were recruited (Table 1). CWH were more likely to have pubertal delay, stunting and wasting than children without HIV. Calcium and vitamin D intake were not significantly different between the two groups. However, CWH had significantly lower muscle mass, muscle strength, TBLH BMCLBM and LS BMAD compared to the uninfected controls. Conclusion: This study, for the first time, investigated the effect of HIV on bone and muscle development sub-Saharan African children. HIV was found to have a profound effect on muscle function and bone mass. Whilst pubertal delay is more common in HIV, it does not account for these differences. The effect of HIV on musculoskeletal health may result in long-term disability and impaired quality of life in the future.

to HIV status and treatments analyzed total body (TB) bone mineral content (BMC) by dual-energy X-ray absorptiometry (DXA) at baseline, 12 and 24 months (mean 2.1, 3.1 and 4.1 years after ART switch, respectively). TB BMC Z-scores adjusted for sex, race, age, and height were generated using reference norms from the US Bone Mineral Density in Childhood Study. During follow-up three groups were compared: HIV+ children on LPV/r or EFV and HIV- children. Results: 207 (94.1%) HIV+ children and 200 (90.9%) HIV- controls completed three visits. Mean ages at the third visit were 8.4 (SD=1.3) and 9.0 (SD=1.6) years respectively. Over 2 years of follow-up, TB BMC Z-scores declined for all three groups: HIV+ on EFV, HIV+ on LPV/r, and HIV- controls at a rate of -0.12, -0.13 and -0.11 per year, respectively. TB BMC Z-scores at baseline, 12 and 24 months were significantly higher among HIV+ on EFV compared to HIV+ on LPV/r (Figure 1A: -0.77 vs -1.14, p=0.04; -0.94 vs -1.34, p<0.01; -1.01 vs -1.40, p=0.04, respectively). With the exception of boys at baseline, differences in BMC Z-scores between ART groups were significant in girls and boys at all three visits (Figure 1B). TB BMC Z-scores at baseline, 12 and 24 months among HIV+ children on EFV were not significantly different from HIV- controls (-0.77 vs -0.82, p=0.54; -0.94 vs -0.95, p=0.95; -1.01 vs -1.04, p=0.71, respectively). Changes of TB BMC Z-scores from baseline to 24 months were not significantly different between children on EFV and those on LPV/r (-0.21 vs -0.26, p=0.53). Conclusion: Despite a slight overall decline in bone mass among HIV+ compared with US population norms over 2 years, bone mass remained higher in HIV+ children switched to EFV compared to those continuing LPV/r, even 4 years after switching. Further, HIV+ children switched to EFV had similar BMC Z-scores as HIV- controls. These findings support our previous recommendations to switch children with sustained viral suppression on first line regimen with LPV/r to EFV. 822 BONE AND RENAL OUTCOMES IN VIROLOGICALLY CONTROLLED ADOLESCENTS SWITCHING TO TDF Kate Braithwaite 1 , Tristan D. McPherson 2 , Stephen M.Arpadi 2 , Stephanie Shiau 3 , Gillian Sorour 1 , Karl Technau 1 , Michael T. Yin 2 1 Empilweni Service and Research Unit, Johannesburg, South Africa, 2 Columbia University Medical Center, NewYork, NY, USA, 3 Rutgers University, Piscataway, NJ, USA Background: Tenofovir disoproxil fumarate (TDF) is included in first line regimens for adolescents living with HIV (ALWH), however associated bone and renal toxicity are concerning. TDF used in combination for treatment- naïve ALWH or those with treatment failure is associated with decreased bone mass. Whether switching to TDF causes decreased bone accrual or bone loss in virologically controlled ALWH is not well established. Methods: We recruited 50 adolescents, ages 15 - 20 years, Tanner stage 4/5, weight > 40 kg, viral load (VL) < 100 copies/mL, and no evidence of kidney or liver disease, that were switched from an abacavir (ABC)-based to TDF-based efavirenz regimen. Bone mass and renal function were assessed at enrolment and week 24 after switch to TDF using dual-x-ray absorptiometry (DXA) and serum renal markers. Undetectable VL was defined as < 50 copies/mL. Body mass index (BMI) was assessed using WHO BMI-for-age charts. Change in lumbar spine (LS) and total body (TB) bone mineral density (BMD) and Z-scores at 24 weeks and eGFR by Revised Schwartz Equation (2009) were assessed by paired t tests, stratified by sex. Results: All participants (48%male) were perinatally infected, with median duration on antiretroviral therapy (ART) of 11.4 years. Six (12%) had a prior AIDS-defining illness. At time of ART switch, median CD4 count was 732 and 38 (76%) had undetectable VL. On BMI, 3 (6%) were classified as thin, and 5 (10%) as overweight by WHO criteria. Before ART switch, median (IQR) LS Z-score and TB Z-score were -1.15 (-2.3;-0.3) and -1.05 (-2.0;-0.3), respectively. Mean change (SD) in LS Z-score was -0.03 (0.25) and TB Z-score was 0.02 (0.24). None had a

Poster Abstracts

821 BONE MASS REMAINS HIGHER AMONG CHILDREN ON EFAVIRENZ VS LOPINAVIR/RITONAVIR Yanhan Shen 1 , Renate Strehlau 2 , Stephanie Shiau 3 , Faeezah Patel 2 , Megan Burke 2 , Louise Kuhn 1 , Ashraf Coovadia 2 , Michael T.Yin 1 , Stephen M.Arpadi 1 1 Columbia University Medical Center, New York, NY, USA, 2 University of the Witwatersrand, Johannesburg, South Africa, 3 Rutgers University, Piscataway, NJ, USA Background: We previously reported South African children living with HIV (HIV+) randomized to remain on a lopinavir/ritonavir (LPV/r)-based antiretroviral therapy (ART) regimen had lower bone mass compared to HIV+ children randomized to switch to efavirenz (EFV) and to controls without HIV (HIV-). This analysis presents two additional years of follow-up. Methods: The CHANGES Bone Study tracks bone health in HIV+ and HIV- children at one site in Johannesburg, South Africa. A single technician blinded

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