Bone health in HIV-infected children, adolescents and young adults: a systematic review

Adults with Perinatally Acquired HIV; Emerging Clinical Outcomes and Data Gaps

In resourced settings, adults living with perinatally acquired HIV are approaching the 5th decade of life. Their clinical and psychological outcomes highlight potential future issues for the much larger number of adolescents growing up with HIV in sub-Saharan Africa, and will inform the development of appropriate healthcare services. Lifelong exposure to HIV, and increasingly to antiretroviral therapy throughout growth and development, contrasts with adults acquiring HIV in later life. This review describes the clinical outcomes for adults living with perinatally acquired HIV including post transition mortality, morbidity and retention in care. Rates of viral suppression, drug resistance and immunological function are explored. Co-morbidities focus on metabolic, cardiovascular, respiratory and bone health with quality-of-life data including neurocognitive functioning and mental health. Sexual and reproductive health including vaccine-preventable disease and the prevention of onward transmission to partners and infants are considered. The data gaps and future research questions to optimise outcomes for this emerging adult cohort are highlighted.

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.

Impaired Bone Architecture in Peripubertal Children With HIV, Despite Treatment With Antiretroviral Therapy: A Cross-Sectional Study From Zimbabwe

HIV infection has multi-system adverse effects in children, including on the growing skeleton. We aimed to determine the association between chronic HIV infection and bone architecture (density, size, strength) in peripubertal children. We conducted a cross-sectional study of children aged 8 to 16 years with HIV (CWH) on antiretroviral therapy (ART) and children without HIV (CWOH) recruited from schools and frequency-matched for age strata and sex. Outcomes, measured by tibial peripheral quantitative computed tomography (pQCT), included 4% trabecular and 38% cortical volumetric bone mineral density (vBMD), 4% and 38% cross-sectional area (CSA), and 38% stress-strain index (SSI). Multivariable linear regression tested associations between HIV status and outcomes, stratified by sex and puberty (Tanner 1-2 versus 3-5), adjusting for age, height, fat mass, physical activity, and socioeconomic and orphanhood statuses. We recruited 303 CWH and 306 CWOH; 50% were female. Although CWH were similar in age to CWOH (overall mean ± SD 12.4 ± 2.5 years), more were prepubertal (ie, Tanner 1; 41% versus 23%). Median age at ART initiation was 4 (IQR 2-7) years, whereas median ART duration was 8 (IQR 6-10) years. CWH were more often stunted (height-for-age Z-score <-2) than those without HIV (33% versus 7%). Both male and female CWH in later puberty had lower trabecular vBMD, CSA (4% and 38%), and SSI than those without HIV, whereas cortical density was similar. Adjustment explained some of these differences; however, deficits in bone size persisted in CWH in later puberty (HIV*puberty interaction p = 0.035 [males; 4% CSA] and p = 0.029 [females; 38% CSA]). Similarly, puberty further worsened the inverse association between HIV and bone strength (SSI) in both males (interaction p = 0.008) and females (interaction p = 0.004). Despite long-term ART, we identified deficits in predicted bone strength in those living with HIV, which were more overt in the later stages of puberty. This is concerning, as this may translate to higher fracture risk later in life. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Comparison of quantitative ultrasonography and dual X-ray absorptiometry for bone status assessment in South African children living with HIV

Children living with HIV (CLHIV) have decreased bone mineral content (BMC) and density (BMD), increasing risk for fracture and future osteoporosis. While DXA is the gold-standard for bone assessments, it lacks availability in resource-constrained settings (RCS). Quantitative ultrasound (QUS) offers an alternative owing to its portability, low cost, ease of handling, and lack of ionizing radiation. While QUS has detected reduced bone quality in CLHIV, the relationship between QUS and DXA in this population remains unexplored. At baseline and 12 months, BMC and BMD of the whole body, lumbar spine, and radius were measured by DXA in a longitudinal cohort of CLHIV in Johannesburg, South Africa. Calcaneal speed of sound (SOS) and broadband ultrasound attenuation (BUA) and radius SOS were obtained by QUS, and calcaneal stiffness index (SI) was calculated. Spearman correlations, with and without HIV stratification, were performed between QUS and DXA measurements at each visit and for absolute difference in measurements between visits. At baseline and 12-months, calcaneal BUA and SI displayed strong positive correlations with DXA, with only modest correlations between radial QUS and DXA at baseline. Longitudinal measures of QUS did not correlate with DXA. At both baseline and 12-months, individuals with DXA whole-body BMD z-score < -1 displayed significantly lower calcaneal BUA and SI. Cross-sectionally, calcaneal QUS correlates strongly with whole body DXA and may represent a viable diagnostic alternative in RCS. Longitudinally, the two methods do not correlate well, possibly reflecting that each method assesses distinct aspects of bone architecture.

Healthcare resource utilization and costs associated with renal, bone and cardiovascular comorbidities among persons living with HIV compared to the general population in Quebec, Canada

There is limited understanding on healthcare utilization and costs of age-related comorbidities such as cardiovascular, bone and renal disease/disorder in people living with human immunodeficiency virus, so we compared comorbidity prevalence and associated healthcare utilization and costs. Through the Quebec health insurance database, people living with human immunodeficiency virus on antiretroviral therapy for ≥6 months from January 2006 to June 2012 were categorized by their comorbidity status using International Classification of Diseases (ICD)-9 codes, and controls without human immunodeficiency virus diagnosis or antiretroviral therapy use were age and gender matched. We compared healthcare utilization and costs. A total of 3,905 people living with human immunodeficiency virus and 11,715 control individuals were included. The mean age of people living with human immunodeficiency virus was 45.3 years and 77.3% were men. Prevalence of comorbidities was higher and occurred earlier in people living with human immunodeficiency virus and increased with older age regardless of human immunodeficiency virus status. Interestingly, bone comorbidity was high (37%) and 5-fold greater in people living with human immunodeficiency virus <20 years than the controls. Polypharmacy and comorbidity scores were greater in people living with human immunodeficiency virus than controls (p<0.01), as were cardiovascular, bone and renal comorbidities (40.3%, 26.0% and 5.5%, respectively; p<0.01). People living with human immunodeficiency virus had higher healthcare utilization and costs than controls largely due to longer hospital stays and prescriptions. Mean total healthcare cost/person/year for people living with human immunodeficiency virus was CAD$6,248 and was highest for those with renal disease (CAD$19,617). Comorbidities in people living with human immunodeficiency virus are more prevalent, occur earlier and incur a higher burden on the healthcare system; earlier screening and improved preventative and management strategies may reduce the burden to people living with human immunodeficiency virus and to the healthcare system.

Vitamin D3 and calcium carbonate supplementation for adolescents with HIV to reduce musculoskeletal morbidity and immunopathology (VITALITY trial): study protocol for a randomised placebo-controlled trial

BACKGROUND

Of the 2 million children living with HIV globally, 90% live in sub-Saharan Africa. Despite antiretroviral therapy, longstanding HIV infection is associated with several chronic complications in children including growth failure, particularly stunting and delayed puberty. Vitamin D deficiency, which is highly prevalent among children living with HIV in sub-Saharan Africa, has a further adverse impact on bone health. This trial aims to establish whether supplementation with vitamin D3 and calcium carbonate improves musculoskeletal health among peripubertal children living with HIV.

METHODS/DESIGN

We will conduct an individually randomised, double-blinded, placebo-controlled trial of weekly high-dose vitamin D3 (20,000 IU) plus daily calcium carbonate (500mg) supplementation for 48 weeks. Eight hundred and forty children living with HIV aged 11-19 years taking ART for ≥6 months will be enrolled and followed up for 96 weeks. The primary outcome is total body less-head bone mineral content for lean mass adjusted for height (TBLH-BMCLBM) Z-score at 48 weeks, measured by dual-energy X-ray absorptiometry (DEXA). Secondary outcomes are DEXA-measured lumbar spine bone mineral apparent density Z-score, number of respiratory infections, lean muscle mass and grip strength at 48 and 96 weeks and TBLH-BMCLBM Z-scores at 96 weeks. Sub-studies will investigate the effect of the intervention on vitamin D3 pathway metabolites and markers of bone turnover, intestinal microbiota, and innate and acquired immune function.

DISCUSSION

This is the largest trial to date of vitamin D supplementation in children living with HIV. Intervening to address deficits in bone accrual in childhood is critical for optimising adolescent and early adult bone health and prevention of later adult osteoporotic fractures. Trial results will draw attention to the need to screen for and treat long-term comorbidities in children living with HIV in resource-limited settings.

TRIAL REGISTRATION

Pan African Clinical Trials Registry PACTR20200989766029 . Registered on 3 September 2020.

Association between handgrip strength and bone mass parameters in HIV-infected children and adolescents. A cross-sectional study

BACKGROUND

Low bone mineral content (BMC) and bone mineral density (BMD) have been identified in human immunodeficiency virus (HIV)-infected children and adolescents. The direct adverse effects of HIV infection and combined antiretroviral therapy (ART) negatively contribute to bone metabolism. A direct relationship between muscle strength levels and BMD in HIV-infected adults and older adults has been described. However, it is unknown whether handgrip strength (HGS) is associated with bone mass in pediatric populations diagnosed with HIV.

OBJECTIVE

To ascertain whether HGS levels are associated with BMC and BMD in HIV-infected children and adolescents.

DESIGN AND SETTING

Cross-sectional study conducted in Florianãpolis, Brazil, in 2016.

METHODS

The subjects were 65 children and adolescents (8-15 years) diagnosed with vertically-transmitted HIV. Subtotal and lumbar-spine BMC and BMD were obtained via dual-emission X-ray absorptiometry (DXA). HGS was measured using manual dynamometers. The covariates of sex, ART, CD4+ T lymphocytes and viral load were obtained through questionnaires and medical records. Sexual maturation was self-reported and physical activity was measured using accelerometers. Simple and multiple linear regression were used, with P < 0.05.

RESULTS

HGS was directly associated with subtotal BMD (β = 0.002; R² = 0.670; P < 0.001), subtotal BMC (β = 0.090; R² = 0.734; P = 0.005) and lumbar-spine BMC (β = 1.004; R² = 0.656; P = 0.010) in the adjusted analyses. However, no significant association was found between HGS and lumbar-spine BMD (β = 0.001; R² = 0.464; P = 0.299).

CONCLUSION

HGS was directly associated with BMD and BMC in HIV-infected children and adolescents.

Effect of HIV infection on growth and bone density in peripubertal children in the era of antiretroviral therapy: a cross-sectional study in Zimbabwe

Background

Faltered linear growth and pubertal delay, which are both common in children with HIV in sub-Saharan Africa, might affect adolescent bone accrual and future fragility fracture risk. We investigated the association of HIV with bone density adjusted for skeletal size in peripubertal children in Zimbabwe.

Methods

We did a cross-sectional study of baseline data from the IMVASK cohort, which enrolled children aged 8–16 years with HIV who had been taking antiretroviral therapy (ART) for at least 2 years, and children of the same age without HIV. Children with HIV were recruited from public sector HIV clinics at Parirenyatwa General Hospital and Harare Central Hospital (Harare, Zimbabwe), and children without HIV were recruited from six schools in the same suburbs that the hospitals serve. Sociodemographic, clinical, and anthropometric data were collected. Dual-energy X-ray absorptiometry (DXA) was used to measure the bone outcomes of total-body less-head bone mineral content for lean mass adjusted for height (TBLH-BMC^LBM), and lumbar spine bone mineral apparent density (LS-BMAD), and we assessed the prevalence of low TBLH-BMC^LBM and low LS-BMAD (defined by Z-scores of less than −2·0). Size adjustment techniques were used to overcome the size dependence of DXA measurement. We used linear regression models, with multiple imputation for missing data, to assess relationships between risk factors and TBLH-BMC^LBM and LS-BMAD Z-scores in children with and without HIV.

Findings

We recruited 303 children with HIV (mean age 12·4 years [SD 2·5]; 151 [50%] girls) and 306 children without HIV (mean age 12·5 years [SD 2·5]; 155 [51%] girls). In children with HIV, median age of HIV diagnosis was 3·0 years (IQR 1·2–5·8), and median ART duration was 8·1 years (6·2–9·5); for 102 (34%) children, ART included tenofovir disoproxil fumarate (TDF). Children with HIV had a higher prevalence of low TBLH-BMC^LBM Z-score than children without HIV (29 [10%] of 279 children with available data vs 18 [6%] of 292 with available data; p=0·066) and a higher prevalence of low LS-BMAD Z-score (40 [14%] of 279 vs 17 [6%] of 293 with available data; p=0·0007). HIV and male sex were associated with earlier pubertal (Tanner) stage. The negative associations between HIV and Z-scores for TBLH-BMC^LBM and LS-BMAD were more pronounced with pubertal maturation, particularly in girls. Among children with HIV, TDF exposure and orphanhood were associated with lower TBLH-BMC^LBM Z-score in confounder-adjusted analysis. Current TDF use (vs non-TDF-based ART) was associated with a reduction in TBLH-BMC^LBM Z-score of 0·41 (95% CI 0·08–0·74; p=0·015) and in LS-BMAD Z-score of 0·31 (0·08–0·69; p=0·12).

Interpretation

Despite ART, HIV is associated with substantial skeletal deficits towards the end of puberty. The extent of bone deficits associated with TDF and its widespread use in children in sub-Saharan Africa are a concern for future adult fracture risk.

Funding

Wellcome Trust.

Impact of vitamin D and calcium supplementation on bone mineral density and bone metabolism among Thai adolescents with perinatally acquired HIV infection: A randomized clinical trial

BACKGROUND

To evaluate the impact of vitamin D and calcium supplementation(VitD/Ca) on lumbar spine bone mineral density(LSBMD) and bone metabolism among Thai adolescents with perinatally acquired HIV(PHIVA).

METHODS

A multicenter, randomized, active-control, open-labeled trial was conducted. PHIVA(aged10-20years) who were on stable cART were enrolled. Baseline LSBMD status was defined as low(z-score≤-2) and normal(z-score>-2). Eligible PHIVA were randomly assigned to receive standard-dose VitD/Ca (400IU/1,200mg daily), or high-dose VitD/Ca supplementation (400IU/1,200mg daily plus ergocalciferol 20,000IU weekly) for 48 weeks (ratio 1:1,stratified by baseline LSBMD). Study outcomes were the changes in LSBMD, LSBMD z-scores, and bone metabolism-related biomarkers (25-hydoxyvitamin D[25OHD], intact parathyroid hormone[iPTH], C-terminal telopeptide[CTX], procollagen type I amino-terminal propeptide[PINP]) from baseline to week48.

RESULTS

Among 200 enrolled PHIVA, a median age was 16 (IQR:14-18)years; 61% were on NNRTI-based cART. The median 25OHD level was 25.5 (IQR:20.8-33.0)ng/ml. After a 48-week VitD/Ca supplementation, LSBMD significantly increased in both treatment groups (high-dose,median:+0.07g/cm 2,IQR:+0.04 to +0.11g/cm 2,P<0.001; standard-dose,median:+0.09g/cm 2, IQR:+0.03 to +0.13g/cm 2,P<0.001). Notably, the change in LSBMD z-scores was significantly greater in high-dose versus standard-dose groups (median:+0.4,IQR:-0.1 to +0.9 versus median:+0.1,IQR:-0.4 to +0.7;P=0.02). The levels of 25OHD increased, whereas iPTH, CTX, and PINP declined significantly in both groups(P<0.05); but no between-group differences were demonstrated.

CONCLUSIONS

Over the 48-week VitD/Ca supplementation, significant increase in LSBMD, and significant decreases in bone metabolism-related markers were observed among our Thai PHIVA in both treatment groups. The improvement in LSBMD z-score was more enhanced with high-dose VitD/Ca supplementation compared with standard-dose. High-dose VitD/Ca supplementation might be considered to promote bone health in this population.

Profiling of Inflammatory Proteins in Plasma of HIV-1-Infected Children Receiving Antiretroviral Therapy

Treatment of HIV-1-infected patients results in improved clinical and immunological conditions, but severe non-AIDS-related conditions still persist. Novel proteomic platforms have identified inflammatory proteins where abundance is dysregulated in adult treated patients, whereas limited data are available in treated HIV-1 infection of children. Using a proteomic plasma profiling approach comprising 92 inflammation-related molecules, we analyzed specimens from 43 vertically HIV-1-infected children receiving antiretroviral treatment (ART) and matched controls in Ethiopia. The infected children were analyzed as a group and separately, according to age of treatment initiation. Proteins displaying a significantly different abundance between groups were hierarchically clustered and presented in heat maps. Random forest analysis was performed to pin-point proteins discriminating between groups; five proteins (STAMBP, CD5, TFG-α, TRANCE, AXIN1) were the strongest prediction factors for treated HIV-1 infection. TRANCE was previously linked to reduced bone mass levels in HIV-1-infected children. CCL4 chemokine, ligand to HIV-1 co-receptor CCR5, was the most critical protein for successful classification between children who initiated ART at different time points. Our data provide evidence that a dysregulated expression of proteins linked to immunological abnormalities and bone metabolism can be found in HIV-1-infected children with prolonged exposure to ART.

Chronic comorbidities in children and adolescents with perinatally acquired HIV infection in sub-Saharan Africa in the era of antiretroviral therapy

Globally, 1·7 million children are living with HIV, of which 90% are in sub-Saharan Africa. The remarkable scale-up of combination antiretroviral therapy has resulted in increasing numbers of children with HIV surviving to adolescence. Unfortunately, in sub-Saharan Africa, HIV diagnosis is often delayed with children starting antiretroviral therapy late in childhood. There have been increasing reports from low-income settings of children with HIV who have multisystem chronic comorbidities despite antiretroviral therapy. Many of these chronic conditions show clinical phenotypes distinct from those in adults with HIV, and result in disability and reduced quality of life. In this Review, we discuss the spectrum and pathogenesis of comorbidities in children with HIV in sub-Saharan Africa. Prompt diagnosis and treatment of perinatally acquired HIV infection is a priority. Additionally, there is a need for increased awareness of the burden of chronic comorbidities. Diagnostic and therapeutic strategies need to be collectively developed if children with HIV are to achieve their full potential.

The IMpact of Vertical HIV infection on child and Adolescent SKeletal development in Harare, Zimbabwe (IMVASK Study): a protocol for a prospective cohort study

INTRODUCTION

The scale-up of antiretroviral therapy (ART) across sub-Saharan Africa (SSA) has reduced mortality so that increasing numbers of children with HIV (CWH) are surviving to adolescence. However, they experience a range of morbidities due to chronic HIV infection and its treatment. Impaired linear growth (stunting) is a common manifestation, affecting up to 50% of children. However, the effect of HIV on bone and muscle development during adolescent growth is not well characterised. Given the close link between pubertal timing and musculoskeletal development, any impairments in adolescence are likely to impact on future adult musculoskeletal health. We hypothesise that bone and muscle mass accrual in CWH is reduced, putting them at risk of reduced bone mineral density (BMD) and muscle function and increasing fracture risk. This study aims to determine the impact of HIV on BMD and muscle function in peripubertal children on ART in Zimbabwe.

METHODS AND ANALYSIS

Children with (n=300) and without HIV (n=300), aged 8-16 years, established on ART, will be recruited into a frequency-matched prospective cohort study and compared. Musculoskeletal assessments including dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, grip strength and standing long jump will be conducted at baseline and after 1 year. Linear regression will be used to estimate mean size-adjusted bone density and Z-scores by HIV status (ie, total-body less-head bone mineral content for lean mass adjusted for height and lumbar spine bone mineral apparent density. The prevalence of low size-adjusted BMD (ie, Z-scores <-2) will also be determined.

ETHICS AND DISSEMINATION

Ethical approval for this study has been granted by the Medical Research Council of Zimbabwe and the London School of Hygiene and Tropical Medicine Ethics Committee. Baseline and longitudinal analyses will be published in peer-reviewed journals and disseminated to research communities.

Stunting and growth velocity of adolescents with perinatally acquired HIV: differential evolution for males and females. A multiregional analysis from the IeDEA global paediatric collaboration

INTRODUCTION

Stunting is a key issue for adolescents with perinatally acquired HIV (APH) that needs to be better understood. As part of the IeDEA multiregional consortium, we described growth evolution during adolescence for APH on antiretroviral therapy (ART).

METHODS

We included data from sub-Saharan Africa, the Asia-Pacific, and the Caribbean, Central and South America regions collected between 2003 and 2016. Adolescents on ART, reporting perinatally acquired infection or entering HIV care before 10 years of age, with at least one height measurement between 10 and 16 years of age, and followed in care until at least 14 years of age were included. Characteristics at ART initiation and at 10 years of age were compared by sex. Correlates of growth defined by height-for-age z-scores (HAZ) between ages 10 and 19 years were studied separately for males and females, using linear mixed models.

RESULTS

Overall, 8737 APH were included, with 46% from Southern Africa. Median age at ART initiation was 8.1 years (interquartile range (IQR) 6.1 to 9.6), 50% were females, and 41% were stunted (HAZ<-2 SD) at ART initiation. Males and females did not differ by age and stunting at ART initiation, CD4 count over time or retention in care. At 10 years of age, 34% of males were stunted versus 39% of females (p < 0.001). Females had better subsequent growth, resulting in a higher prevalence of stunting for males compared to females by age 15 (48% vs. 25%) and 18 years (31% vs. 15%). In linear mixed models, older age at ART initiation and low CD4 count were associated with poor growth over time (p < 0.001). Those stunted at 10 years of age or at ART initiation had the greatest growth improvement during adolescence.

CONCLUSIONS

Prevalence of stunting is high among APH worldwide. Substantial sex-based differences in growth evolution during adolescence were observed in this global cohort, which were not explained by differences in age of access to HIV care, degree of immunosuppression or region. Other factors influencing growth differences in APH, such as differences in pubertal development, should be better documented, to guide further research and inform interventions to optimize growth and health outcomes among APH.

Tenofovir Has Minimal Effect on Biomarkers of Bone Health in Youth with HIV Receiving Initial Antiretroviral Therapy

Both HIV infection and tenofovir disoproxil fumarate (TDF) treatment adversely impact bone metabolism and may lead to osteopenia, which has critical implications for youth with HIV (YWH). This study evaluates changes in the biomarkers of bone metabolism and inflammation among YWH receiving initial treatment with TDF- and non-TDF-containing antiretroviral therapies (ARTs). YWH [n = 23, median age 21 years (range 18-24), 87% male, 61% African American] were assessed for inflammatory and bone metabolism biomarkers at enrollment, after 48 weeks of TDF-containing ART, and 96 weeks of ART without TDF with continued viral suppression. Spearman's rank correlation evaluated biomarker associations. Bone alkaline phosphatase, parathyroid hormone, and osteopontin increased after TDF treatment. All fell after TDF was discontinued. Levels of RANKL and osteoprotegerin did not change throughout the study. There was little correlation between biomarkers of bone metabolism and either macrophage or lymphocyte activation at any time point. Our results establish baseline associations between bone metabolism and immune biomarkers for this population, and find that before CD4 T cell decline chronic inflammation does not perturb biomarkers of bone metabolism among YWH. The adverse effects of TDF on bone health may be marginal for YWH at the early stages of disease.

Older age at initiation of antiretroviral therapy predicts low bone mineral density in children with perinatally-infected HIV in Zimbabwe

BACKGROUND

Perinatally-acquired HIV infection commonly causes stunting in children; how this affects bone and muscle development is unclear. We investigated differences in bone and muscle mass and muscle function between children with HIV (CWH) and uninfected children.

SETTING

Cross-sectional study of CWH (6-16 years) receiving antiretroviral therapy (ART) for >6 months and similar aged children testing HIV-negative at primary health clinics in Zimbabwe.

METHODS

From Dual-energy X-ray Absorptiometry (DXA) we calculated total-body less-head (TBLH) Bone Mineral Content (BMC) for lean mass adjusted-for-height (TBLH-BMCLBM) Z-scores, and lumbar spine (LS) Bone Mineral Apparent Density (BMAD) Z-scores.

RESULTS

The 97 CWH were older (mean age 12.7 vs. 10.0 years) and taller (mean height 142 cm vs. 134 cm) than 77 uninfected. However, stunting (height-for-age Z-score ≤ -2) was more prevalent in CWH (35% vs. 5%, p < 0.001). Among CWH, 15% had low LS-BMAD (Z-score ≤ -2) and 13% low TBLH-BMCLBM, vs. 1% and 3% respectively in those uninfected (both p ≤ 0.02). After age, sex, height and puberty adjustment, LS-BMAD was 0.33 SDs (95%CI -0.01, 0.67; p = 0.06) lower in CWH, with no differences by HIV status in TBLH-BMCLBM, lean mass (0.11 [-0.03, 0.24], p = 0.11) or grip strength (0.05 [-0.16, 0.27], p = 0.62). However, age at ART initiation was correlated with both LS-BMAD Z-score (r = -0.33, p = 0.001) and TBLH-BMCLBM Z-score (r = -0.23, p = 0.027); for each year ART initiation was delayed a 0.13 SD reduction in LS-BMAD was seen.

CONCLUSION

Size-adjusted low bone density is common in CWH. Delay in initiating ART adversely affects bone density. Findings support immediate ART initiation at HIV diagnosis.

Safety, efficacy, and pharmacokinetics of single-tablet elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide in virologically suppressed, HIV-infected children: a single-arm, open-label trial

BACKGROUND

No once-daily single-tablet regimen is available for HIV-infected children under 12 years. The single-tablet, fixed-dose combination of elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide is a once-daily, integrase strand transfer inhibitor-based regimen approved in the USA and European Union for individuals aged 12 years or older. In this study, we aimed to assess the pharmacokinetics, safety, and efficacy of this regimen in virologically suppressed, HIV-infected children.

METHODS

In this single-arm, open-label trial, we enrolled virologically suppressed, HIV-infected children from five hospital clinics in Uganda, the USA, and Thailand. Eligible participants were aged 6-11 years, weighed 25 kg or more, had virological suppression (<50 copies of HIV-1 RNA per mL) on a stable regimen for at least 6 months, CD4 count of more than 100 cells per μL, and no history of resistance to elvitegravir, emtricitabine, tenofovir alafenamide, or tenofovir. All participants received the available fixed-dose oral formulation of elvitegravir 150 mg, cobicistat 150 mg, emtricitabine 200 mg, and tenofovir alafenamide 10 mg once per day. Primary outcomes were the pharmacokinetic parameters area under the curve (AUC) concentration at the end of the dosing interval (AUC_tau) for elvitegravir and the AUC from time zero to the last quantifiable concentration (AUC_last) of tenofovir alafenamide, treatment-emergent serious adverse events, and all treatment-emergent adverse events. Results from baseline to week 24 are reported, unless specified otherwise. Primary and safety analyses included all enrolled participants who received one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT01854775.

FINDINGS

Between July 27 and Sept 28, 2015, we screened 26 children, of whom 23 were enrolled and initiated treatment. Median age was 10 years (IQR 8-11), median weight was 30·5 kg (IQR 27·5-33·0), and all participants had virological suppression. The mean AUC_tau of elvitegravir was 33 814 ng × h/mL (coefficient of variation 58%), and the mean AUC_last of tenofovir alafenamide was 333 ng × h/mL (45%). Exposures to elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide were higher, but modestly so, than those previously reported in adults. All 23 participants tolerated the regimen well; there were no serious adverse events or adverse event-related discontinuations. All participants maintained virological suppression (HIV-1 RNA <50 copies per mL) at week 24. CD4 count decreased by a median of -130 cells per μL (range -472 to 266) with little change in CD4 cell percentage (-2·1%, range -8·4 to 5·9).

INTERPRETATION

The fixed-dose combination of elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide was efficacious and well tolerated in virologically suppressed, HIV-infected children. Although plasma exposure of all components was higher than has been reported in adults, there were no safety concerns and the overall bone and renal safety profile was favourable. These data support the use of this regimen in children at least 25 kg in weight.

FUNDING

Gilead Sciences.

HIV and Bone Complications: Understudied Populations and New Management Strategies

The higher risk of osteoporosis and fracture associated with HIV infection and certain antiretrovirals has been well established and the need for risk stratification among older adults increasingly recognized. This review focuses upon emerging data on bone complications with HIV/HCV coinfection, in children and adolescents, and with pre-exposure prophylaxis (PrEP), as well as new management strategies to minimize the negative effects of ART on bone.

Safety, efficacy, and pharmacokinetics of a single-tablet regimen containing elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide in treatment-naive, HIV-infected adolescents: a single-arm, open-label trial

BACKGROUND

The prodrug tenofovir alafenamide is associated with improved renal and bone safety compared with tenofovir disoproxil fumarate. We aimed to assess safety, pharmacokinetics, and efficacy of this single-tablet, fixed-dose combination of elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide in HIV-infected, treatment-naive adolescents.

METHODS

We did a 48 week, single-arm, open-label trial in treatment-naive adolescents with HIV from ten hospital clinics in South Africa, Thailand, Uganda, and the USA. Eligible participants were aged 12-18 years, with plasma HIV-1 RNA of at least 1000 copies per mL, a CD4 count of at least 100 cells per μL, and estimated glomerular filtration rate of at least 90 mL/min per 1·73 m² by the Schwartz formula, bodyweight of at least 35 kg, and an HIV-1 genotype with sensitivity to elvitegravir, emtricitabine, and tenofovir. Participants received a single-tablet regimen once per day with food (administered by their parent or carer) containing 150 mg elvitegravir, 150 mg cobicistat, 200 mg emtricitabine, and 10 mg tenofovir alafenamide. Study visits to the clinic occurred at weeks 1, 2, 4, 8, 12, 16, 24, 32, 40, and 48. The coprimary endpoints were the pharmacokinetic parameters of area under the curve (AUC) concentration at the end of the dosing interval (AUC_tau) for elvitegravir and the AUC from time zero to the last quantifiable concentration (AUC_last) for tenofovir alafenamide, incidence of treatment-emergent serious adverse events, and all adverse events that emerged after treatment started (including data for bone mineral density). All participants who received one dose of study drug were included in the primary and safety analyses. This trial is registered with ClinicalTrials.gov, number NCT01854775.

FINDINGS

Between May 22, 2013, and July 22, 2014, we enrolled 50 participants, and all 50 received the assigned treatment; 24 participated in the intensive pharmacokinetic assessment. 48 patients completed the 48 weeks of treatment; two discontinued (one withdrew consent at week 8, one was lost to follow-up at week 12). The regimen was well tolerated and no discontinuations related to adverse events occurred. The mean AUC_tau for elvitegravir was 23 840 ng × h per mL (coefficient of variation [CV] 25·5%), and the mean AUC_last for tenofovir alafenamide was 189 ng × h per mL (CV 55·8%). Four participants (8%) had a serious adverse event, one of which (intermediate uveitis) was deemed related to the study regimen but resolved without treatment interruption. The most common study drug-related adverse events were nausea (in ten participants), abdominal pain (in six), and vomiting (in five). Exposures to the elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide regimen were similar to those previously noted in adults.

INTERPRETATION

The elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide regimen was well tolerated and achieved component plasma pharmacokinetic exposures similar to those in adults. Although non-comparative with a small sample size, these data support the use of this regimen in HIV-infected adolescents and its timely assessment in younger children.

FUNDING

Gilead Sciences.

Prediction of Areal Bone Mineral Density and Bone Mineral Content in Children and Adolescents Living With HIV Based on Anthropometric Variables

Children and adolescents living with HIV have low bone mass for age. There are reliable and accurate methods for evaluation of bone mass, however, alternative methods are necessary, especially, for application in limited-resource scenarios. Anthropometry is a noninvasive and low cost method that can predict bone mass in healthy youths. The aim of the study was to develop predictive equations for bone mineral content and bone mineral density in children and adolescents living with HIV based on anthropometric variables. Forty-eight children and adolescents of both sexes (24 females) from 7 to 17 years, living in greater Florianopolis area, Santa Catarina, Brazil, who were under clinical follow-up at "Hospital Infantil Joana de Gusmão", participated in the study. Dual-energy X-ray absorptiometry was used to evaluate whole-body bone mineral content (BMC) and areal bone mineral density (aBMD). Height, body weight, bone diameters, arm circumference, and triceps skinfold were measured and the body mass index and arm muscle area were calculated. Multiple regression models were fitted to predict BMC and aBMD, using backward selection (p ≥ 0.05). Two predictive models with high R² values (84%-94%) were developed. Model 1 to estimate aBMD [Y = -0.1450124 + (height × 0.0033807) + (age × 0.0146381) + (body mass index × 0.0158838) + (skin color × 0.0421068)], and model 2 to estimate BMC [Y = 1095.1 + (body weight × 45.66973) + (age × 31.36516) + (arm circumference × -53.27204) + (femoral diameter × -9.594018)].The predictive models using anthropometry provided reliable estimates and can be useful to monitor aBMD and BMC in children and adolescents living with human immunodeficiency virus where limited resources are available.

Adverse bone health and abnormal bone turnover among perinatally HIV-infected Asian adolescents with virological suppression

OBJECTIVES

This study aimed to determine the prevalence of low bone mass and assess its relationship with abnormal bone turnover among HIV-infected Asian adolescents.

METHODS

A multicentre, cross-sectional study was conducted at four paediatric HIV centres in Thailand and Indonesia. Perinatally HIV-infected adolescents aged 10-18 years receiving antiretroviral therapy (ART) with virological suppression (HIV RNA < 400 copies/mL) were enrolled. Study assessments included lumbar spine (L2-L4) dual-energy X-ray absorptiometry and measurement of bone turnover markers. Bone mineral density (BMD) and bone mineral apparent density (BMAD) Z-scores were calculated based on Thai normative age- and sex-matched references. Low bone mass was defined as BMD or BMAD Z-scores ≤ -2.

RESULTS

Of 396 participants, 57% were female. The median age was 15.0 [interquartile range (IQR) 13.3-16.9] years, and 73% were in Tanner stage 3-5. At enrolment, the median CD4 T-cell count was 734 (IQR 581-907) cells/μL, and 37% were on protease inhibitor (PI)-based regimens. The overall prevalence of lumbar spine BMD and BMAD Z-scores ≤ -2 were 16.4% and 8.3%, respectively. Z-scores were lower with older age, female sex, body mass index (BMI) <5th percentile, boosted PI exposure and CD4 T-cell percentage < 15% before ART initiation. Increased bone turnover markers were inversely associated with BMD and BMAD Z-scores.

CONCLUSIONS

Low bone mass was linked to older age, female sex, low BMI, boosted PI exposure, and poor immunological status before ART commencement in our cohort of perinatally HIV-infected Asian adolescents. Dysregulation of bone turnover was associated with bone demineralization. Screening for low bone mass should be implemented to identify individuals who might benefit from interventions to preserve bone health.

Adverse bone health among children and adolescents growing up with HIV

Adverse bone health is one of the important non-communicable conditions during the course of life-long HIV treatment. Adolescence is the critical period of bone mineral acquisition for attaining adult peak bone mass. With traditional and HIV-related risk factors, adolescents growing with HIV have a greater chance of having impaired bone mineral density (BMD). Prevalence of low BMD has been reported in 16-32% of HIV-infected adolescents from middle-income countries. The deep interaction between the immune and skeletal systems, called the immunoskeletal interface, is proposed as one of the underlying mechanisms of adverse bone health in HIV-infected individuals. Dual-energy X-ray absorptiometry (DXA) is a standard tool to assess BMD among HIV-infected adolescents. Non-invasive imaging techniques such as quantitative computed tomography (QCT) and quantitative magnetic resonance imaging (QMRI) provide more information on true volumetric density and bone microarchitecture. To date, there are no paediatric recommendations on the treatment and prevention of adverse bone health. Having a healthy lifestyle, routine weight-bearing exercises and adequate dietary intake are the standard approaches to optimise bone health. There are several ongoing randomised clinical trials using pharmacological treatment options, for example vitamin D, calcium and alendronate to improve bone health among this population.