Bone health in HIV-infected children and adolescents

Understanding HIV-Exposed Uninfected Children: A Narrative Review

The widespread implementation of antiretroviral therapy has significantly reduced HIV-related mortality and mother-to-child transmission. Despite being HIV-uninfected, HIV-exposed children (HEU) seem to face heightened risks of immune dysfunction, cardiometabolic diseases, growth delays, reduction in bone mineral density, and neurocognitive impairments compared to HIV-unexposed uninfected peers. These vulnerabilities can be attributed to maternal immune dysregulation during pregnancy, antiretroviral (ART) toxicity, HIV exposure, and adverse socioeconomic and nutritional environments. Emerging evidence highlights the impact of antiviral therapy exposure, particularly tenofovir disoproxil fumarate, on HEU mitochondrial dysfunction, bone resorption, neurocognitive delays, and zidovudine on cardiac abnormalities. This narrative review explores the multisystem effects of ART exposure in HEU children, focusing on immune function, neurodevelopment, cardiovascular health, growth, and bone metabolism. By synthesizing findings from diverse studies, the review aims to provide a comprehensive understanding of the potential risks associated with ART regimens and identify future research priorities to improve outcomes for HEU children.

Bone Accrual Trajectories in Children and Adolescents with Perinatal HIV Infection

CONTEXT

Low bone mineral density (BMD) has been reported in children and adolescents living with perinatally-acquired HIV (PHIV). Little is known about their bone accrual through puberty compared to an uninfected healthy cohort.

OBJECTIVE

To compare bone accrual in PHIV and healthy children.

DESIGN

PHIV children aged 7-16 years had dual energy X-ray absorptiometry (DXA) at entry, 2 years, and then at least 2 years later. Bone accrual was compared to healthy children from the Bone Mineral Density in Childhood Study (BMDCS).

SETTING

United States academic clinical research centers.

PATIENTS

172 PHIV; 1321 BMDCS.

ANALYSIS

We calculated height-adjusted whole-body and spine BMD and bone mineral content (BMC) Z-scores in PHIV using BMDCS reference curves. We fit piecewise weighted linear mixed effects models with change points at 11 and 15 years, adjusted for age, sex, race, height Z-score, and Tanner stage, to compare BMD and BMC Z-scores across actual age by cohort.Main Outcome Measure: BMD/BMC Z-scores.

RESULTS

Height-adjusted whole-body BMD and BMC Z-scores in PHIV were lower across age compared to BMDCS children. Spine BMD Z-score across age was higher in PHIV after height adjustment. Whole-body and spine bone area tended to be lower in PHIV. PHIV had slower accrual in whole-body and spine bone area before 14 years. After 15 years, bone area accruals were similar, as were height-adjusted spine BMC Z-scores, across age.

CONCLUSIONS

PHIV had persistent deficits in all measures except height-adjusted spine BMD and BMC Z-scores. Data are needed on PHIV followed to adulthood.

A Three-Year Follow-Up of Bone Density Among Thai Adolescents With Perinatally Acquired HIV After Completion of Vitamin D and Calcium Supplementation

PURPOSE

To determine changes in bone mineral density (BMD) and bone metabolism-related biomarkers among Thai adolescents with perinatally acquired HIV infection (PHIVA) at 3 years following completion of vitamin D and calcium (VitD/Cal) supplementation.

METHODS

An observational follow-up study was conducted among PHIVA who received 48-week VitD/Cal supplementation (either high-dose [3,200 IU/1,200 mg daily] or standard-dose [400 IU/1,200 mg daily]). Lumbar spine BMD (LSBMD) was assessed by dual-energy x-ray absorptiometry. Serum 25-hydroxyvitamin D, intact parathyroid hormone, and bone turnover markers were measured. Changes in LSBMD z-scores and other bone parameters at 3 years after stopping VitD/Cal supplementation compared with baseline or week 48 of supplementation were assessed among participants previously receiving high-dose and standard-dose VitD/Cal supplementation.

RESULTS

Of 114 enrolled PHIVA, 46% and 54% had previously received high-dose and standard-dose VitD/Cal supplementation, respectively. The median age was 20 years; 53% were male. At 3 years after completion of VitD/Cal supplementation, we observed a significant decline in 25-hydroxyvitamin D and increase in intact parathyroid hormone but no significant rebounds of C-terminal telopeptides of collagen type I and procollagen type I amino-terminal propeptides and no significant changes in LSBMD z-scores among PHIVA in both treatment groups, compared with the measurements at week 48 of supplementation. Notably, LSBMD z-scores at 3 years after stopping VitD/Cal supplements were not significantly altered from baseline evaluations in both PHIVA groups.

DISCUSSION

Three years after completion of high-dose or standard-dose VitD/Cal supplementation, LSBMD z-scores of our Thai PHIVA were not significantly changed from baseline and week 48 of supplementation. VitD/Cal supplementation of PHIVA during periods of peak bone mass accrual may have sustained and long-term skeletal benefits.

Bone mineral density among children living with HIV failing first-line anti-retroviral therapy in Uganda: A sub-study of the CHAPAS-4 trial

BACKGROUND

Children living with perinatally acquired HIV (CLWH) survive into adulthood on antiretroviral therapy (ART). HIV, ART, and malnutrition can all lead to low bone mineral density (BMD). Few studies have described bone health among CLWH in Sub-Saharan Africa. We determined the prevalence and factors associated with low BMD among CLWH switching to second-line ART in the CHAPAS-4 trial (ISRCTN22964075) in Uganda.

METHODS

BMD was determined using dual-energy X-ray Absorptiometry (DXA). BMD Z-scores were adjusted for age, sex, height and race. Demographic characteristics were summarized using median interquartile range (IQR) for continuous variables and proportions for categorical variables. Logistic regression was used to determine the associations between each variable and low BMD.

RESULTS

A total of 159 children were enrolled (50% male) with median age (IQR) 10 (7-12) years, median duration of first -line ART 5.2(3.3-6.8) years; CD4 count 774 (528-1083) cells/mm3, weight-for-age Z-score -1.36 (-2.19, -0.65) and body mass index Z-score (BMIZ) -1.31 (-2.06, -0.6). Low (Z-score≤ -2) total body less head (TBLH) BMD was observed in 28 (18%) children, 21(13%) had low lumbar spine (LS) BMD, and15 (9%) had both. Low TBLH BMD was associated with increasing age (adjusted odds ratio [aOR] 1.37; 95% CI: 1.13-1.65, p = 0.001), female sex (aOR: 3.8; 95% CL: 1.31-10.81, p = 0.014), low BMI (aOR 0.36:95% CI: 0.21-0.61, p<0.001), and first-line zidovudine exposure (aOR: 3.68; 95% CI: 1.25-10.8, p = 0.018). CD4 count, viral load and first- line ART duration were not associated with TBLH BMD. Low LS BMD was associated with increasing age (aOR 1.42; 95% CI: 1.16-1.74, p = 0.001) and female sex: (aOR 3.41; 95% CI: 1.18-9.8, p = 0.023).

CONCLUSION

Nearly 20% CLWH failing first-line ART had low BMD which was associated with female sex, older age, first-line ZDV exposure, and low BMI. Prevention, monitoring, and implications following transition to adult care should be prioritized to identify poor bone health in HIV+adolescents entering adulthood.

Fracture prevalence and its association with bone density among children living with HIV in Zimbabwe

OBJECTIVES

HIV infection impairs bone density in children living with HIV (CLWH). We aimed to determine the prevalence of self-reported fracture (past or current), associated risk factors and disability, by HIV status in Zimbabwean children.

DESIGN

Cross-sectional study.

METHODS

We recruited CLWH aged 8-16 years taking antiretroviral therapy (ART) for ≥2 years from HIV clinics, and HIV-uninfected children from schools in Harare. Interviewer-administered questionnaires collected data on fracture site and management, sociodemographics, dietary calcium and vitamin D, physical activity and HIV history. Dual-energy X-ray absorptiometry (DXA) measured size-adjusted bone density.

RESULTS

We recruited 303 CLWH [mean (SD) age 12.5 (2.5) years; 50% female] and 306 children without HIV [12.5 (2.5) years; 51% female]. Median age at HIV diagnosis in CLWH was 3.0 years [interquartile range (IQR) 1.2, 5.9], and median ART duration 8.1 years [IQR 6.2, 9.5]. 53.8% CLWH had self-reported disability and/or functional impairment, vs. 29.4% children without HIV. Fracture prevalence was 5.9% with no difference by HIV status [21/306 (6.9%) vs. 14/303 (4.6%), P  = 0.24]. Male sex was associated with fractures. Low size-adjusted bone density ( Z -score < -2) was associated with prevalent fractures in CLWH {risk ratio [RR] 1.14 (95% confidence interval (CI) -0.02, 2.29]}, but not in children without HIV [RR -0.04 (-2.00, 1.91)], P -interaction = 0.27. All sought medical attention for their fracture(s), but CLWH were less often admitted to hospital [2/14 (14.3%) vs. 7/21 (33.3%)].

CONCLUSION

Prevalent fractures may be associated with low lumbar spine bone density in CLWH. Fracture surveillance and strategies to reduce future fracture risk are warranted as CLWH enter adulthood.

Antiretroviral Therapy in Children and Adolescents: A Look Into Modern Single Tablet Regimens

Single tablet regimens (STRs) have simplified antiretroviral therapy (ART) over the years in the adult human immunodeficiency virus (HIV) population. However, there is still a prevalent need to simplify regimens in children and adolescents living with HIV. Finding the optimal regimen requires a multi-factorial approach due to their complex pharmacokinetic profiles throughout childhood and the challenges and limitations of medication non-adherence in the pediatric population. These challenges include pill size, available formulations, palatability, and caregiver health literacy, which can all affect the proper administration of medications. The complexity of this population implies the importance of customizing everyone's antiretroviral regimen so that the patient and family can successfully adhere to the therapy. The current recommendations for ART in the adult and pediatric populations are similar, yet the use of STRs are limited. The goal of this review was to assess current data on available STRs and determine their utility as ART in the pediatric population.

Persistently lower bone mass and bone turnover among South African children living with well controlled HIV

OBJECTIVE

We evaluated longitudinal trends and associations between bone mass, bone turnover and inflammatory markers among South African children living with HIV (CLHIV) and controls.

DESIGN

We previously reported decreased bone mass among CLHIV independent of marked inflammation and increased bone turnover. The goal of this study was to evaluate longitudinal changes in bone mass, bone turnover and inflammation over 2 years.

METHODS

Longitudinal analyses were conducted among 220 CLHIV and 220 controls. Anthropometric measurements, physical activity, antiretroviral regimen, virologic and immunologic status, whole body (WB) and lumbar spine (LS) bone mineral content (BMC) and bone mineral density (BMD) were collected (enrollment, 12 and 24 months). Bone turnover markers including C-telopeptide of type I collagen (CTx) and procollagen type I N-terminal propeptide (P1NP) and inflammatory markers including interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), soluble CD14 and high-sensitivity C-reactive protein (hsCRP) were collected at enrollment and 24 months.

RESULTS

Compared with controls, CLHIV had significantly lower mean WB-BMC, WB-BMD, WB-BMC z scores, LS-BMC and LS-BMD as well as lower bone formation (P1NP) and resorption (CTx), and higher hsCRP and soluble CD14 over 24 months. CLHIV on efavirenz (EFV) had consistently lower TNF-alpha and IL-6 compared with those on ritonavir-boosted lopinavir (LPV/r) at all time points.

CONCLUSION

Over 2 years of follow-up, South African CLHIV had persistently lower bone mass, bone turnover, and macrophage activation. Lower bone mass and higher pro-inflammatory cytokine profiles were consistently observed among those on LPV/r-based compared with EFV-based regimens.

Long-Term Administration of Abacavir and Etravirine Impairs Semen Quality and Alters Redox System and Bone Metabolism in Growing Male Wistar Rats

Highly active antiretroviral therapy (HAART) is used in HIV-infected patients. Alongside the prolongation of patients' life, adverse side effects associated with long-term therapy are becoming an increasing problem. Therefore, optimizing of HAART is extremely important. The study is aimed at evaluating the toxicity of abacavir and etravirine in monotherapy on the reproductive system, liver, kidneys, and bones in young, sexually mature, male rats. Thirty-six 8-week-old male Wistar rats randomized into three 12-animal groups received either normal saline (control), abacavir 60 mg/kg (AB group), or etravirine 40 mg/kg (ET group) once daily for 16 weeks. Semen morphology, oxide-redox state parameters (MDA, SOD, catalase, GPx, glutathione, GSH/GSSG ratio) in tissue homogenates (testes, liver, kidneys), and serum samples were studied. In bones, microcomputed tomography and a four-point bending test were performed. Total sperm count, sperm concentration, motility, and sperm morphology did not differ significantly in AB or ET groups compared to the control. In the flow cytometry of semen, an increased percentage of cells with denatured DNA was noticed for both tested drugs. However, no significant changes of oxide-redox state in testicular homogenates were found, except of increased SOD activity in the AB-receiving group. Additionally, ET significantly altered catalase and GPx in the liver and SOD activity in kidneys. Abacavir decreased catalase in the liver and GSH levels in kidneys. AB caused significant changes to bone microarchitecture (bone volume fraction, trabecular number, connectivity density, total porosity) and increased Young's modulus. Etravirine had a greater impact on macrometric parameters of bones (tibial index, mid-tibial diameter, femur length). After 4 weeks in the ET group, a lower 1,25-dihydroxyvitamin D₃ serum concentration was found. The results showed that abacavir and etravirine disturb oxidative stress. An increase in the percentage of sperms with chromatin damage suggests decreased fertility in rats receiving the studied drugs. Both drugs affected bone formation in growing rats. Additionally, etravirine disturbed vitamin D metabolism.

Non-communicable Diseases in Pregnant and Postpartum Women Living with HIV: Implications for Health Throughout the Life Course

PURPOSE OF REVIEW

The development of non-communicable diseases (NCDs) in pregnant women living with HIV can be a harbinger of future NCD-related morbidity and mortality. This review focuses on the NCDs that complicate pregnancy and the postpartum period, including hypertensive complications, hyperglycemic disorders, excessive gestational weight gain, and bone mineral density losses. For each disease process, we explore the role of HIV as a possible driver of excess risk, the immediate consequences of these complications on pregnancy outcomes and maternal and infant health, and possible implications for long-term women's health.

RECENT FINDINGS

Countries with the highest burden of HIV also shoulder a high burden of NCDs that complicate pregnancy, including hypertensive disorders, hyperglycemic disorders, weight gain, and osteopenia. This double burden of disease is a significant public health threat for reproductive-age women, with the potential for serious short- and long-term consequences for both women and their infants. Additionally, as the global first-line antiretroviral therapy regimens increasingly include integrase inhibitors, unhealthy weight gain associated with this drug class poses additional risk for NCD-related pregnancy complications and their persistence postpartum. Further research is needed to better define prevalence of NCD complications in pregnancy, elucidate HIV-specific and traditional factors associated with poor outcomes, and to develop interventions to reduce risk and avoid downstream complications in those at highest risk.

Accelerated aging in perinatally HIV-infected children: clinical manifestations and pathogenetic mechanisms

Background: Premature aging and related diseases have been documented in HIV-infected adults. Data are now emerging also regarding accelerated aging process in HIV-infected children.

Methods: A narrative review was performed searching studies on PubMed published in English language in 2004-2017, using appropriate key words, including “aging”, “children”, “HIV”, “AIDS”, “immunosenescence”, “pathogenesis”, “clinical conditions”.

Results: Premature immunosenescence phenotype of B and T cells in HIV-infected children is mediated through immune system activation and chronic inflammation. Ongoing inflammation processes have been documented by increased levels of pathogen-associated molecular patterns (PAMPS), increased mitochondrial damage, higher levels of pro-inflammatory cytokines, and a positive correlation between sCD14 levels and percentages of activated CD8⁺ cells. Other reported features of premature aging include cellular replicative senescence, linked to an accelerated telomeres shortening. Finally, acceleration of age-associated methylation pattern and other epigenetic modifications have been described in HIV-infected children. All these features may favor the clinical manifestations related to premature aging. Lipid and bone metabolism, cancers, cardiovascular, renal, and neurological systems should be carefully monitored, particularly in children with detectable viremia and/or with CD4/CD8 ratio inversion.

Conclusion: Aging processes in children with HIV infection impact their quality and length of life. Further studies regarding the mechanisms involved in premature aging are needed to search for potential targets of treatment.

A Global Research Agenda for Adolescents Living With HIV

Supplemental Digital Content is Available in the Text.

Background:

Despite growing interest in undertaking research in adolescent HIV, the current pace of interventional research in particular remains very low compared with the needs of adolescents living with HIV (ALHIV). More robust evidence is needed to inform innovative and targeted interventions that bridge research gaps, inform policy, and improve outcomes for adolescents. A global research prioritization exercise was undertaken by WHO and CIPHER to focus efforts on priority research in the context of diminishing resources.

Methods:

The Child Health and Nutrition Research Initiative (CHNRI) methodology was adapted and used. Outcomes were reviewed by an expert group and 5 priority themes identified for testing, treatment, and service delivery, accounting for existing policies, published literature, and ongoing research.

Results:

A total of 986 research questions were submitted by 323 individuals from 67 countries. For HIV testing, priority themes included strategies and interventions to improve access, uptake, and linkage to care, and self-testing, particularly for key populations. For treatment, priorities included strategies to monitor and improve adherence, novel drug delivery systems, preventions and management of coinfections, optimal drug sequencing, and short- and long-term outcomes. For service delivery, priorities included service delivery models across the cascade, strategies to improve retention in care and sexual and reproductive health, support for pregnant ALHIV, and the provision of psychosocial support.

Conclusions:

This prioritized research agenda assists in focusing future research in ALHIV and will help to fill critical knowledge gaps. Key stakeholders, donors, program managers, and researchers should all support these priority questions and themes to collaboratively drive the adolescent HIV research agenda forward.

Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand

The aim of this study was to describe growth during puberty in young people with vertically acquired HIV.

Growth and pubertal development in HIV-infected adolescents

PURPOSE OF REVIEW

We present an overview of recent research in the inter-related areas of growth and pubertal development among adolescents with HIV. Growth deficits early in childhood can lead to delayed puberty, with subsequent effects on pubertal growth spurts and bone health.

RECENT FINDINGS

Impaired growth remains a critical concern, particularly in low-resource settings, where stunting, wasting and underweight remain pervasive. Antiretroviral treatment (ART) initiation results in improved growth, with greatest growth recovery in the first years and more improvement in weight than in height. However, even years after ART initiation, growth deficits persist in low-resource settings (LRS), and adolescents appear at particularly increased risk. The high prevalence of stunting translates to delays in pubertal onset and sexual maturity. In contrast, HIV-infected adolescents in developed countries do not demonstrate persistent wasting, yet still have delayed pubertal development. Impaired growth increases the risk for mortality, virologic failure, and abnormal bone health, as well as increased depression and stigma.

SUMMARY

Early initiation of ART across all age groups regardless of immunological status is essential for restoring growth. Coordination of ART initiation, nutritional supplementation programs, and concurrent prophylaxis is required to ameliorate growth deficits and pubertal delays, particularly in LRS.

Vitamin D supplementation decreases immune activation and exhaustion in HIV-1-infected youth

BACKGROUND

Heightened immune activation and exhaustion drive HIV disease progression and comorbidities. Vitamin D has pleiotropic immunomodulatory effects, but little is known about the effects of supplementation in HIV. Our study investigates changes in immune activation and exhaustion markers after 12 months of supplementation in virologically suppressed HIV-infected youth with vitamin D insufficiency.

METHODS

This is a randomized, active-control, double-blind trial investigating with three different vitamin D3 doses (18,000 [standard/active-control dose], 60,000 [moderate dose] and 120,000 IU/month [high dose]) in 8-25-year-old HIV-infected youth on combination antiretroviral therapy with baseline serum 25-hydroxyvitamin D (25(OH)D) concentrations ≤30 ng/ml. Only subjects (n=51) who maintained an undetectable HIV-1 RNA over the 12-month study period were included in this analysis.

RESULTS

Baseline serum 25(OH)D concentrations and immune activation/exhaustion markers were not different between groups. By 12 months, 25(OH)D increased significantly within each dosing group with the greatest increase and most sustained concentrations ≥30 ng/ml in the high-dose group. Overall, all measured markers decreased with CD4 activation (CD4+CD38+HLA-DR+), CD8 activation (CD8+CD38+HLA-DR+), CD4 exhaustion (CD4+CD38+HLA-DR+PD1+) and inflammatory monocytes (CD14+CD16+) reaching statistical significance. When analysed separately, there were no significant decreases in the moderate- or standard-dose groups, but CD4 and CD8 activation and inflammatory monocytes decreased significantly in the high-dose group.

CONCLUSIONS

Vitamin D supplementation decreased markers of T-cell activation/exhaustion and monocyte activation in HIV-infected youth, with subjects given the highest dose (120,000 IU/month) showing the greatest decreases. These data suggest that high-dose vitamin D supplementation may attenuate immune activation and exhaustion, and serve as adjuvant therapy to antiretroviral therapy in HIV. ClinicalTrials.gov identifier: NCT01523496.