Low bone mass in behaviorally HIV-infected young men on antiretroviral therapy: Adolescent Trials Network Study 021B

Association between total bilirubin and bone mineral density level in adolescents

Background

Increasing bone mass accumulation in adolescence and obtaining greater peak bone mass is one of the effective methods to prevent osteoporosis in the future. We aimed to examine the association between total bilirubin and bone mineral density (BMD) level in adolescents.

Methods

We used the data from 2005–2010 and 2013–2014 cycles of National Health and Nutrition Examination Survey (NHANES). The BMD levels in the region of lumbar spine and femoral regions, including total femur, femoral neck, trochanter, and intertrochanter were measured. Univariable and multivariable linear regression model were used to assess the relationship between total bilirubin concentration and BMD.

Results

A total of 3741 participants aged 12–19 years were ultimately included in the study. There were 1997 (53.38%) males and 1744 (46.62%) females. Univariate analysis results showed that age, sex, race, education, income, body mass index, dietary calcium intake, and diabetes were correlated with BMD levels. Compared with the lowest quartile of total bilirubin concentration, the highest quartile of total bilirubin concentration was positively associated with BMD levels in the regions of total femur (β = 0.036, 95% CI = 0.021 to 0.050, P < 0.001), femur neck (β = 0.030, 95% CI = 0.016 to 0.044, P < 0.001), trochanter (β = 0.033, 95% CI = 0.019 to 0.046, P < 0.001), intertrochanter (β = 0.040, 95% CI = 0.023 to 0.056, P < 0.001), and lumbar spine (β = 0.032, 95% CI = 0.018 to 0.045, P < 0.001). We also observe the same trend in sensitivity analysis (P for trend < 0.001).

Conclusion

Our study demonstrated that total bilirubin concentration was positively associated with BMD levels in adolescents in United States. Total bilirubin concentration might be a protective marker against bone loss in adolescents.

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.

People with HIV infection had lower bone mineral density and increased fracture risk: a meta-analysis

A meta-analysis to investigate the difference in fracture risk between individuals with and without HIV infection was performed. People living with HIV had lower bone mineral density (BMD) and greater risks of overall fractures and fragility fractures. Reducing fragility and maintaining skeletal strength for PLWH are urgently needed for this population.

PURPOSE

The introduction of effective antiretroviral therapy increased the life expectancy of people living with HIV (PLWH). This population now faces problems related to aging such as decreased bone mineral density (BMD) and increased fracture risk. Some antiretroviral therapies may also negatively impact bone health. We performed a meta-analysis to investigate the difference in the fracture risk between individuals with and without HIV infection.

METHODS

We compared BMD, risk of fragility fracture, and risk of all fracture between the two groups. This study included 35 articles with 106,994 PLWH and 228,794,335 controls.

RESULTS

PLWH had lower lumbar spine and hip BMD than controls. PLWH had a higher prevalence of all fracture events (4.08% versus 0.44%) and fragility fractures (2.66% versus 2.19%). The relative risks of all and fragility fractures of PLWH were 1.91 (95% confidence interval (CI), 1.46-2.49; p < 0.001) and 1.68 (95% CI: 1.40-2.01; p < 0.001). PLWH also had more vertebral fractures (1.26% versus 0.37%; RR, 1.97; 95% CI: 1.22-3.2; p < 0.05), hip fractures (1.38% versus 0.81%; RR, 1.88; 95% CI: 0.99-3.57; p = 0.05), and wrist fractures (1.38% versus 1.29%; RR, 1.67; 95% CI: 1.13-2.45; p < 0.05) than healthy controls. The pooled incidence of fractures was 1.72 per 100 person-years in PLWH and 1.29 in healthy controls.

CONCLUSION

PLWH had lower BMD and greater risks of all fractures and fragility fractures. Reducing fragility and maintaining skeletal strength for PLWH are urgently needed for this population.

Immune Markers and Their Association with Bone Density in Children, Adolescents, and Young Adults with Perinatally Acquired HIV

To describe distributions of immune markers in children and young adults by sex and HIV status, and within groups, investigate associations of immune markers with bone density across Tanner stage. Using data and samples from 353 participants in a cross-sectional study in youth with perinatally acquired HIV (PHIV) and matched HIV-negative controls, distributions of inflammation and activation immune markers were described by sex and HIV status. Correlations and structural equation models (SEM) were used to explore marginal and multivariable associations of the immune markers with bone density and to assess whether patterns of association varied by sex and HIV status. Immune marker distributions did not differ by sex, but there were some differences by HIV status. Correlation patterns among bone, body composition, and immune markers were similar across the sex and HIV status groups. Conclusions from SEMs were limited by small sample sizes, but there was some indication that patterns of association between bone density and certain immune markers differed in male PHIV with more advanced Tanner stage compared to the other three groups. In conclusion, distributions of bone density, body composition, and immune markers may vary by sex and HIV status, although associations among these outcomes within sex and HIV status groups appear similar. Bone density of male PHIV appears to be more negatively affected than females, regardless of female HIV status. Larger longitudinal studies across Tanner stages are needed to further explore potential biological relationships between immune markers and bone density in youth living with HIV.

Bone Update: Is It Still an Issue Without Tenofovir Disoproxil Fumarate?

PURPOSE OF REVIEW

In the era of modern bone-friendly antiretroviral therapy (ART) regimens for people living with HIV (PLWH), this review discusses the research gaps and management concerns that remain for individuals who have already been exposed to ART with negative effects on bone metabolism, especially children and adolescents who have not acquired peak bone mass, and older adults who have additional risk factors for fracture.

RECENT FINDINGS

Data now support the use of avoidance of TDF and use of bone-friendly regimens that include integrase strand transfer inhibitors in PLWH with increased risk of fracture for either ART initiation or switch. Despite significant advances in our understanding of ART choice for PLWH with regard to bone health, additional diagnostic tests to determine fracture risk and management strategies beyond ART choice are necessary, especially in vulnerable PLWH populations, such as children and adolescents and older adults.

Changes in Bone Mass After Discontinuation of Preexposure Prophylaxis With Tenofovir Disoproxil Fumarate/Emtricitabine in Young Men Who Have Sex With Men: Extension Phase Results of Adolescent Trials Network Protocols 110 and 113

Human immunodeficiency virus-seronegative men aged 15-22 years who lost bone mineral density (BMD) during tenofovir disoproxil fumarate/emtricitabine preexposure prophylaxis (PrEP) showed BMD recovery 48 weeks following PrEP discontinuation. Lumbar spine and whole body BMD z-scores remained below baseline 48 weeks off PrEP in participants aged 15-19 years. Clinical Trials Registration. NCT01772823 (ATN 110) and NCT01769456 (ATN 113).

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.

Bone mass preservation with high-dose cholecalciferol and dietary calcium in HIV patients following antiretroviral therapy. Is it possible?

OBJECTIVE

To evaluate whether treatment with 100,000 IU/month (equivalent to 3200 IU/day) of cholecalciferol and 1 g/day of dietary calcium supplementation in HIV patients following different cART regimens yields normal levels of vitamin D3 and PTH as well as whether changes in bone mineral density are clinically significant.

METHODS

Consecutive HIV patients following different cART regimens received 100,000 IU/month (equivalent to 3200 IU/day) of cholecalciferol and 1 g/day of dietary calcium supplementation. The participants underwent BMD assessment via dual energy X-ray absorptiometry of the spine and hip at baseline (T0) and after 24 months (T1). Levels of 25(OH) vitamin D3 and parathyroid hormone (PTH) were assessed at T0 and T1. Quantitative variables were assessed with a paired t-test, independent t-test or analysis of variance, as appropriate. A chi-squared analysis was used to assess the association between qualitative variables. A p-value <0.05 was considered significant. Patients were divided into three groups depending on the cART regimen.

RESULTS

A total of 79 patients were included (40 males, 51% and 39 females, 49%), with a mean age of 46.6 (SD ±11.2) years, a baseline CD4 count of 649 cells/µl and a mean 25 hydroxycholecalciferol (25(OH) D3) value of 25 + 10 ng/ml. After 24 months, the 25(OH) D3 increased to 40 + 11 ng/ml. The initial BMDs at T0 were estimated as 0.919 (±0.27) and 0.867 (±0.14) g/cm² at the spine and hip, respectively. After 24 months, the BMD was 0.933 (±0.15) g/cm² at the spine and 0.857 (±0.14) g/cm² at the hip. Based on a BMD change exceeding 3%, a worsening was observed in 23% of patients at the spine and 27% at the hip, whereas stability or improvement was demonstrated in 77% of patients at the spine and 73% at the hip. Subgrouping patients based on antiretroviral therapy indicated that, at T1, there was a statistically significant increase in vitamin D3 concentration in all patients, while PTH concentration was not significantly reduced in patients taking tenofovir or efavirenz. BMD stability or improvement was demonstrated in 77% of patients at the spine and 73% at the hip after 24 months. The multivariate analysis confirms a decrease in vitamin D3 and an increase in PTH levels in smokers, as well higher vitamin D3 concentrations in males and lower spine BMDs in menopausal females.

CONCLUSION

The proposed protocol of cholecalciferol and dietary calcium supplementation is safe and valid for correcting vitamin D abnormalities in almost all patients as well as reducing PTH levels in a high percentage of patients; however, it is not sufficient for normalization, particularly in patients exposed to tenofovir or efavirenz. At the spine, no significant BMD change was found in any of the therapy groups. At the hip, our data confirm a modest negative effect on bone mass caused by tenofovir and efavirenz.

People Living With HIV: Implications for Rehabilitation Nurses

PURPOSE

The aim of this study was to present a brief overview of challenges faced by people living with HIV (PLHIV) as they age, to discuss the relevance of HIV to rehabilitation nurses, and to provide evidence-based recommendations for rehabilitation professionals working with PLHIV.

DESIGN

Current issues article.

METHODS

Literature review related to age-related comorbidities in PLHIV with implications for rehabilitation nurses.

FINDINGS

Rehabilitation nurses must be prepared to address issues specific to people living with HIV including sensitivity and privacy regarding HIV status and increased risk of delayed or complicated healing. Rehabilitation nurses should also promote self-management behavior to optimize health in people living with HIV.

CONCLUSIONS

Understanding unique characteristics of PLHIV as well as applying focused assessment and tailored interventions in PLHIV will give rehabilitation nurses the tools to successfully guide PLHIV through the rehabilitation process and optimize clinical outcomes.

CLINICAL RELEVANCE

As people with HIV age and experience acute and chronic comorbidities, they will require the clinical expertise of rehabilitation nurses in the process to successfully transition through acute and subacute health care and regain function.

Prevalence of and risk factors for low bone mineral density in Spanish treated HIV-infected patients

Objectives

Several studies have involved antiretroviral therapy in the pathogenesis of low bone mineral density (BMD), while others have not confirmed this association. In this study we analyze the impact of HIV status, traditional risk factors and antiretroviral therapy in BMD in an HIV-infected population living in Madrid.

Material and methods

We performed a cross-sectional analysis of 107 individuals infected with HIV and exposed to antiretroviral treatment to estimate the prevalence of decreased BMD. Bone mineral density of lumbar spine and femoral neck was measured by dual-energy X-ray absorptiometry. In a multivariate analysis variables related with HIV status, antiretroviral drugs and traditional risk factors were included.

Results

Low BMD was diagnosed in 63 participants (58.9%), including osteoporosis in 11 (10%). At least one cause of osteoporosis was identified in 43 patients (40%), with a deficiency of vitamin D in 86 (89%) and secondary hyperparathyroidism in 30 (28%). In multivariate analysis, increasing age, a treatment based on boosted PI and tenofovir DF, and previous exposure to tenofovir were identified as independent risk factors for a decreased BMD in both lumbar spine and femoral neck.

Conclusions

We have confirmed a high prevalence of reduced BMD, which is favoured by ritonavir-boosted PI and TDF. Bone safety should continue to be evaluated in clinical trials and cohort studies in order to demonstrate that the new drugs offer additional advantages regarding the impact on BMD.

Soluble CD14, CD163, and CD27 biomarkers distinguish ART-suppressed youth living with HIV from healthy controls

OBJECTIVE

To define inflammatory pathways in youth living with HIV infection (YLWH), assessments of biomarkers associated with lymphocyte and macrophage activation, vascular injury, or bone metabolism were performed in YLWH in comparison with healthy controls (HC).

DESIGN

Longitudinal multicenter study comparing biomarkers in YLWH suppressed on antiretroviral therapy (ART), those with ongoing viral replication, and HC were compared using single blood samples obtained at end of study.

METHODS

Twenty-three plasma proteins were measured by ELISA or multiplex assays. Principal component analysis (PCA) was used to define contributions of individual biomarkers to define outcome groups.

RESULTS

The study cohort included 129 predominantly African American, male participants, 21-25 years old at entry. Nine biomarkers of lymphocyte and macrophage activation and cardiovascular injury differed between HC and YLWH. Significant positive correlations were identified between lymphocyte and macrophage activation biomarkers among HC and YLWH. Correlations distinct to YLWH were predominantly between biomarkers of macrophage and vascular inflammation. PCA of outcome groups showed HC and suppressed YLWH clustering together for lymphocyte activation biomarkers, whereas macrophage activation markers showed all YLWH clustering distinct from HC. Cardiovascular biomarkers were indistinguishable across groups. Averaged variable importance projection to assess single biomarkers that maximally contribute to discriminate among outcome groups identified soluble CD27, CD14, and CD163 as the 3 most important with TNFα and LPS also highly relevant in providing separation.

CONCLUSIONS

Soluble inflammatory and lymphocyte biomarkers sufficiently distinguish YLWH from HC. Persistent macrophage activation biomarkers may provide a means to monitor consequences of HIV infection in fully suppressed YLWH.

The Association of Fat and Lean Tissue With Whole Body and Spine Bone Mineral Density Is Modified by HIV Status and Sex in Children and Youth

BACKGROUND

HIV-infected (HIV-pos) male children/youth showed lower bone mineral density at sexual maturity than HIV-uninfected (HIV-neg) females. It is not known whether complications of HIV disease, including abnormal body fat distribution, contribute to lower bone accrual in male HIV-pos adolescents.

METHODS

In a cross-sectional study, we evaluated the relationship between body composition (fat and lean mass) and bone mass in HIV-pos and HIV-neg children/youth and determined if it is modified by HIV status and sex. We used generalized estimating equations to simultaneously model the effect of fat/lean mass on multiple bone outcomes, including total body bone mineral density and bone mineral content and spine bone mineral density. We evaluated effect modification by HIV and sex.

RESULTS

The analysis cohort consisted of 143 HIV-neg and 236 HIV-pos, of whom 55% were black non-Hispanic and 53% were male. Ages ranged from 7 to < 25 years. Half of the children/youth were at Tanner stage 1 and 20% at Tanner 5. Fat mass was more strongly positively correlated with bone mass in HIV-neg than HIV-pos children/youth and these relationships were more evident for total body bone than spine outcomes. Within HIV strata, fat mass and bone were more correlated in female than male children/youth. The relationship between lean mass and bone varied by sex, but not by HIV status.

CONCLUSIONS

HIV disease diminishes the positive relationship of greater fat mass on bone mass in children/youth. Disruptions in body fat distribution, which are common in HIV disease, may have an impact on bone accretion during pubertal development.

Effects of Vitamin D Supplementation on Bone Mineral Density and Bone Markers in HIV-Infected Youth

BACKGROUND

Low bone mineral density (BMD) is a significant comorbidity in HIV. However, studies evaluating vitamin D supplementation on bone health in this population are limited. This study investigates changes in bone health parameters after 12 months of supplementation in HIV-infected youth with vitamin D insufficiency.

METHODS

This is a randomized, active-control, double-blind trial investigating changes in bone parameters with 3 different vitamin D3 doses [18,000 (standard/control dose), 60,000 (moderate dose), and 120,000 IU/monthly (high dose)] in HIV-infected youth 8-25 years old with baseline serum 25-hydroxyvitamin D (25(OH)D) concentrations <30 ng/mL. BMD and bone turnover markers were measured at baseline and 12 months.

RESULTS

One hundred two subjects enrolled. Over 12 months, serum 25(OH)D concentrations increased with all doses, but the high dose (ie, 120,000 IU/monthly) maintained serum 25(OH)D concentrations in an optimal range (≥30 or ≥20 ng/mL) throughout the study period for more subjects (85% and 93%, respectively) compared with either the moderate (54% and 88%, respectively) or standard dose (63% and 80%, respectively). All dosing groups showed some improvement in BMD; however, only the high-dose arm showed significant decreases in bone turnover markers for both procollagen type 1 aminoterminal propeptide (-3.7 ng/mL; P = 0.001) and Β-CrossLaps (-0.13 ng/mL; P = 0.0005).

CONCLUSIONS

High-dose vitamin D supplementation (120,000 IU/mo) given over 12 months decreases bone turnover markers in HIV-infected youth with vitamin D insufficiency, which may represent an early, beneficial effect on bone health. High vitamin D doses are needed to maintain optimal serum 25(OH)D concentrations.

Brief Report: Macrophage Activation in HIV-Infected Adolescent Males Contributes to Differential Bone Loss by Sex: Adolescent Trials Network Study 021

Accumulating evidence suggests that rates of low bone mass are greater in HIV-infected males than females. Of 11 biomarkers assessed by sex and HIV-status, HIV-infected males had increased levels of soluble CD14 which inversely correlated with bone mineral content and bone mineral density measures, suggesting macrophage activation as a possible mechanism of differential bone loss.

Modeling aging in HIV infection in nonhuman primates to address an emerging challenge of the post-ART era

The advent of antiretroviral therapy (ART) has dramatically improved both quality and length of life for subjects infected with human immunodeficiency virus (HIV), delaying or preventing progression to acquired immunodeficiency syndrome (AIDS). However, the virus induces aging-related changes to the immune system which confound treatment. Additionally, the normal physiologic events that occur during aging lead to deficiencies in immunity which not only exacerbate HIV pathogenesis but also trigger a variety of comorbidities. Here, the synergistic linkage between aging and HIV infection is examined in regard to the immunological and pathological mechanisms that drive both senescence and disease progression. The use of NHPs to investigate potential therapeutic strategies to control the deleterious consequences of aging with HIV infection is also reviewed.

An increased rate of fracture occurs a decade earlier in HIV+ compared with HIV- men

OBJECTIVES

To determine the incidence of fracture among aging HIV-infected (HIV+) and uninfected men (HIV-). To evaluate factors independently associated with fracture risk.

DESIGN

Prospective, multicenter cohort study of men with or at risk for HIV.

METHODS

Outcome measures: all fractures (excluding skull, face and digits) and fragility fractures (vertebral column, femur, wrist and humerus) were collected semiannually in 1221 HIV+ and 1408 HIV- men aged at least 40. Adjusted incident rate ratios (aIRR) with an interaction term for age (40-49, 50-59 and ≥60 years) and HIV serostatus were estimated with Poisson regression models accounting for additional risk factors.

RESULTS

Fracture incidence increased with age among both HIV+ and HIV- men. Although there was no significant difference in fracture incidence by HIV serostatus among men aged 40-49 years, the HIV+ men aged 50-59 years had a significantly higher incidence of all fractures [aIRR: 2.06 (1.49, 2.84)] and fragility fractures [aIRR: 2.06 (1.21, 3.50)] compared with HIV- participants of similar age. HIV modified the effect of age on all fractures (P = 0.002) but did not significantly modify the effect for fragility fractures (P = 0.135). Hypertension increased the rate of all fractures by 32% after adjustment for covariates [aIRR: 1.32 (1.04, 1.69)].

CONCLUSION

Fracture incidence increased with age among HIV+ and HIV- men but was higher among HIV+ men. A significant increase in fracture incidence was found among 50-59-year-old HIV+ men, highlighting the importance of osteoporosis screening for HIV-infected men above the age of 50.

An HIV Preexposure Prophylaxis Demonstration Project and Safety Study for Young MSM

BACKGROUND

Young men who have sex with men (YMSM) are a key population for implementation of preexposure prophylaxis (PrEP) interventions. This open-label study examined adherence to PrEP and assessed sexual behavior among a diverse sample of YMSM in 12 US cities.

METHODS

Eligible participants were 18- to 22-year-old HIV-uninfected MSM who reported HIV transmission risk behavior in the previous 6 months. Participants were provided daily tenofovir disoproxil fumarate/emtricitabine (Truvada). Study visits occurred at baseline, monthly through week 12, and then quarterly through week 48. Dried blood spots were serially collected for the quantification of tenofovir diphosphate (TFV-DP).

RESULTS

Between March and September 2013, 2186 individuals were approached and 400 were found to be preliminarily eligible. Of those 400, 277 were scheduled for an in-person screening visit and 200 were enrolled (mean age = 20.2; 54.5% black, 26.5% Latino). Diagnosis of sexually transmitted infections, including urethral and rectal chlamydial/gonococcal infection and syphilis, at baseline was 22% and remained high across visits. At week 4, 56% of participants had TFV-DP levels consistent with ≥4 pills per week. By week 48, 34% of participants had TFV-DP levels consistent with ≥4 pills per week, with a noticeable drop-off occurring at week 24. Four HIV seroconversions occurred on study (3.29/100 person-years). Condomless sex was reported by >80% of participants, and condomless anal sex with last partner was associated with higher TFV-DP levels.

CONCLUSIONS

Acceptability of PrEP was high, and most participants achieved protective drug levels during monthly visits. As visit frequency decreased, so did adherence. YMSM in the United States may need PrEP access in youth-friendly settings with tailored adherence support and potentially augmented visit schedules.

Bone health in HIV-infected children and adolescents

PURPOSE OF REVIEW

Chronic HIV infection and exposure to antiretroviral therapy compromises bone health in children and adolescents, potentially impacting their long-term quality of life. Thus, the purpose of this article is to review the most recent literature on this topic in HIV-infected children and adolescents.

RECENT FINDINGS

Recent studies continue to demonstrate bone abnormalities in HIV-infected children and adolescents, whether HIV is acquired perinatally or during adolescence. Researchers have employed new modalities, both high tech and those that can be utilized in resource-limited settings, to better assess bone health. New data suggest that this population may also be experiencing an increase incidence of fractures, and they may not acquire the same peak bone mass as their HIV-uninfected counterparts. Reassuringly, however, in-utero tenofovir exposure does not appear to have a significant impact on bone health in HIV-exposed, uninfected infants.

SUMMARY

HIV-infected children and adolescents are exposed to HIV and antiretroviral therapy for many decades starting early in life and during the most critical time for skeletal growth and bone mass accrual. Recent findings underscore the need for further research on bone in this population. Longitudinal studies are especially needed to evaluate long-term risk of osteoporosis and fracture.

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.

HIV infection and bone disease

The success of antiretroviral therapy in treating HIV infection has greatly prolonged life expectancy in affected individuals, transforming the disease into a chronic condition. A number of HIV-associated non-AIDS comorbidities have emerged in the ageing HIV-infected population, including osteoporosis and increased risk of fracture. The pathogenesis of fracture is multifactorial with contributions from both traditional and HIV-specific risk factors. Significant bone loss occurs on initiation of antiretroviral therapy but stabilizes on long-term therapy. Fracture risk assessment should be performed in HIV-infected individuals and bone mineral density measured when indicated. Lifestyle measures to optimize bone health should be advised and, in individuals at high risk of fracture, treatment with bisphosphonates considered.

HIV and Orthopaedics: Musculoskeletal Manifestations and Outcomes

➤Advances in combined antiretroviral therapy (cART) in recent years have transformed HIV infection into a chronic disease when treatment is available, increasing a patient's life expectancy and the chances that orthopaedic surgeons will encounter such patients in their clinical practice.➤Musculoskeletal manifestations in patients with HIV infection are common and sometimes are the initial presentation of the disease. Knowledge about neoplasms and associated conditions affecting muscle, bones, and joints is essential for successful management.➤Since the advent of cART, total joint arthroplasty has been shown to be a safe procedure; however, perioperative infection is still a small risk in patients with uncontrolled viral loads or CD4 counts of <400 cells/mm(3).➤With regard to trauma surgery, the rates of early and late infection around implants, as well as union rates, are comparable with those in the HIV-negative population; however, there is an increased risk of pulmonary, renal, and infectious or septic complications in the polytrauma setting.➤Factors such as CD4 count, nutritional status, cART therapy, viral load count, and other comorbidities (hemophilia, infection among intravenous drug users, etc.) should be considered when treating these patients in order to optimize their clinical outcomes.

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.

Profiles of Risk Among HIV-Infected Youth in Clinic Settings

Despite the rising number of new HIV infections among youth, few tailored interventions for youth living with HIV (YLH) have been developed and rigorously tested. Developing tailored interventions necessitates identifying different profiles of YLH and understanding how risk and protective factors cluster together. Obtaining this critical information requires accessing a sufficiently large sample of YLH from diverse geographic settings such as those available through the Adolescent Trials Network for HIV Interventions (ATN). We recruited a cross-sectional sample of 1,712 YLH from ATN clinics; participants completed a survey on psychosocial and health factors. Using latent class analysis on nine composite variables representing risk factors, we identified five classes distinguished by substance use, sexual behavior, and pregnancy history and differing on health outcomes. Findings suggest a need for tailored interventions addressing multiple risky behaviors of HIV-infected youth and research to clarify how intervention effectiveness may differ by risk profile.

Effects of Emtricitabine/Tenofovir on Bone Mineral Density in HIV-Negative Persons in a Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

Daily preexposure prophylaxis (PrEP) with oral emtricitabine and tenofovir disoproxil fumarate (FTC/TDF) decreases the risk of human immunodeficiency virus (HIV) acquisition. Initiation of TDF decreases bone mineral density (BMD) in HIV-infected people. We report the effect of FTC/TDF on BMD in HIV-seronegative men who have sex with men and in transgender women.

METHODS

Dual-energy X-ray absorptiometry was performed at baseline and 24-week intervals in a substudy of iPrEx, a randomized, double-blind, placebo-controlled trial of FTC/TDF PrEP. Plasma and intracellular tenofovir concentrations were measured in participants randomized to FTC/TDF.

RESULTS

In 498 participants (247 FTC/TDF, 251 placebo), BMD in those randomized to FTC/TDF decreased modestly but statistically significantly by 24 weeks in the spine (net difference, -0.91% [95% confidence interval {CI}, -1.44% to -.38%]; P = .001) and hip (-0.61% [95% CI, -.96% to -.27%], P = .001). Changes within each subsequent 24-week interval were not statistically significant. Changes in BMD by week 24 correlated inversely with intracellular tenofovir diphosphate (TFV-DP), which was detected in 53% of those randomized to FTC/TDF. Net BMD loss by week 24 in participants with TFV-DP levels indicative of consistent dosing averaged -1.42% ± 29% and -0.85% ± 19% in the spine and hip, respectively (P < .001 vs placebo). Spine BMD tended to rebound following discontinuation of FTC/TDF. There were no differences in fractures (P = .62) or incidence of low BMD.

CONCLUSIONS

In HIV-uninfected persons, FTC/TDF PrEP was associated with small but statistically significant decreases in BMD by week 24 that inversely correlated with TFV-DP, with more stable BMD thereafter.

CLINICAL TRIALS REGISTRATION

NCT00458393.

Prevalence and predictors of low bone mineral density and fragility fractures among HIV-infected patients at one Italian center after universal DXA screening: sensitivity and specificity of current guidelines on bone mineral density management

Low bone mineral density (BMD) is frequent in HIV infection regardless of the use of antiretroviral therapy (ART). Uncertainties remain, however, as to when in HIV infection BMD screening should be performed. We designed a prospective study to estimate the efficacy of universal BMD screening by dual-energy X-ray absorptiometry (DXA). Since April 2009 through March 2011, HIV patients attending our Center were offered femoral/lumbar DXA to screen BMD. Low BMD for chronological age, that is significant osteopenia, was defined as a Z-score ≤ -2.0 at femur and lumbar spine. Nontraumatic bone fractures (NTBFs) were evaluated. The final sample included 163 patients. A Z-score ≤ -2.0 at any site was observed in 19.6% of cases: among these, 18.8% had no indication to DXA using current Italian HIV guidelines for BMD screening. A lower femoral Z-score was independently associated with lower BMI, AIDS diagnosis, HCV co-infection, antiretroviral treatment, and NTBFs; a lower lumbar Z-score with age, BMI, Nadir CD4 T-cell counts, and NTBFs. Prevalence of NTBFs was 27.0%, predictors being male gender, HCV co-infection, and lower femoral Z-scores. Our results suggest that measuring BMD by DXA in all HIV patients regardless of any further specification may help retrieving one-fifth of patients with early BMD disorders not identified using current criteria for selective screening of BMD.

HIV infection and osteoporosis

In the past two decades, the life expectancy of people living with HIV infection has increased significantly, and osteoporosis has emerged as a significant comorbidity. In addition to traditional risk factors for fracture, specific factors related to HIV infection are also likely to contribute, including antiretroviral therapy. The heterogeneity of the HIV-infected population in terms of age and ethnicity presents many challenges to the prevention and management of bone disease, and further studies are required to establish optimal approaches to risk assessment and treatment.

Skeletal health in adults with HIV infection

Concern has been raised that HIV infection, its treatment, or both adversely affect skeletal health. Cross-sectional studies show that bone mineral density (BMD) is 3-5% lower in patients infected with HIV than in uninfected controls, but patients with HIV infection are, on average, 5 kg lighter than uninfected people. After this weight difference is accounted for, BMD differences are smaller and not clinically relevant. Longitudinal studies show short-term BMD loss of 2-4% over 1-2 years when antiretroviral therapy is started, followed by longer periods of BMD increase or stability. Losses are greatest with treatment regimens that contain tenofovir. Patients infected with HIV have slightly higher fracture rates than controls, but the increased risk of fracture is substantially attenuated by adjustment for traditional risk factors for fracture. These reassuring findings suggest that management of skeletal health in HIV should follow guidelines for the general population. In general, effective antiretroviral treatment and avoidance of undernutrition are the two most important factors for maintenance of skeletal health in patients infected with HIV.

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

BACKGROUND

Children and adolescents, who either acquire HIV infection perinatally, from contaminated blood products or via sexual transmission early in life, have the greatest cumulative exposure to the negative direct and indirect effects of HIV infection and ART on bone, which may lead to increased lifetime risk for osteoporosis and fracture. We conducted a systematic review to evaluate the literature on bone health in children and adolescents with HIV.

METHODS

We performed a comprehensive search of the Medline, Scopus, and Cochrane Library databases (up to April 1, 2014) for studies that reported on bone imaging or bone fractures in HIV-infected children, adolescents, or young adults.

RESULTS

A total of 32 publications met our inclusion criteria. Seventeen studies were cross-sectional and 15 were longitudinal. The majority of studies were conducted in high-income countries, three in middle-income countries and none in low-income countries. Overall, the studies we reviewed indicate that measures of bone mass are reduced, with increased prevalence of low BMD in children and adolescents with HIV. However, the studies are highly variable with respect to comparison sources, measurement methods, adjustment techniques for body size or growth retardation, and highlighted risk factors, including aspects related to medication exposures as well as the effects of HIV infection per se.

CONCLUSION

HIV infection appears to be associated with decreased bone accrual throughout childhood and adolescence. Initial studies indicate that sub-optimal bone accrual may be persistent and result in reduced peak bone mass, an important determinant of future risk of osteoporosis and fracture. Important areas for future research include evaluation of bone mass, bone quality and fracture risk across the life course among those with early-life infection with HIV, particularly in resource-limited settings where the majority of children with HIV live.

Low bone mineral density in patients with well-suppressed HIV infection: association with body weight, smoking, and prior advanced HIV disease

BACKGROUND

Human immunodeficiency virus (HIV) and combination antiretroviral therapy (cART) may both contribute to the higher prevalence of osteoporosis and osteopenia in HIV-infected individuals.

METHODS

Using dual-energy X-ray absorptiometry, we compared lumbar spine, total hip, and femoral neck bone mineral density (BMD) in 581 HIV-positive (94.7% receiving cART) and 520 HIV-negative participants of the AGEhIV Cohort Study, aged ≥45 years. We used multivariable linear regression to investigate independent associations between HIV, HIV disease characteristics, ART, and BMD.

RESULTS

The study population largely consisted of men who have sex with men (MSM). Osteoporosis was significantly more prevalent in those with HIV infection (13.3% vs 6.7%; P<.001). After adjustment for body weight and smoking, being HIV-positive was no longer independently associated with BMD. Low body weight was more strongly negatively associated with BMD in HIV-positive persons with a history of a Centers for Disease Control and Prevention class B or C event. Interestingly, regardless of HIV status, younger MSM had significantly lower BMD than older MSM, heterosexual men, and women.

CONCLUSIONS

The observed lower BMD in treated HIV-positive individuals was largely explained by both lower body weight and more smoking. Having experienced symptomatic HIV disease, often associated with weight loss, was another risk factor. The low BMD observed in younger MSM remains unexplained and needs further study.

Osteoporosis and fracture risk associated with HIV infection and treatment

Osteoporosis has emerged as an important co-morbidity of HIV infection and a modest increase in fracture risk has been documented. Bone loss from the spine and hip occurs after initiation of antiretroviral therapy but most data indicate that bone mineral density is stable in HIV-infected individuals established on long-term antiretroviral therapy. Assessment of fracture probability should be performed in individuals who have clinical risk factors for fracture. Adequate dietary calcium intake and vitamin D status should be ensured and in individuals with a high fracture probability, bisphosphonate therapy may be appropriate.

Exploration of the Effect of Tobacco Smoking on Metabolic Measures in Young People Living with HIV

We conducted cross-sectional, multicenter studies in HIV-positive young women and men to assess metabolic and morphologic complications from tobacco smoking in 372 behaviorally infected HIV-positive youth, aged 14–25 years. Measurements included self-reported tobacco use, fasting lipids, glucose, fat distribution, and bone mineral density (BMD; dual-energy X-ray absorptiometry scans). Overall, 144 (38.7%) self-reported smoking tobacco and 69 (47.9%) of these reported smoking greater than five cigarettes per day. Smokers versus nonsmokers had lower mean total cholesterol (146.0 versus 156.1 mg/dL; P < 0.01) and lower mean total body fat percent (24.1% versus 27.2%, P = 0.03). There was no difference between smokers and nonsmokers in fasting glucose or BMD. There appear to be only minimal effects from tobacco smoking on markers of cardiac risk and bone health in this population of HIV-positive youth. While these smokers may not have had sufficient exposure to tobacco to detect changes in the outcome measures, given the long-term risks associated with smoking and HIV, it is critical that we encourage HIV-positive youth smokers to quit before the deleterious effects become apparent.

HIV infection, bone metabolism, and fractures

With the advent of high active antiretroviral therapy there was a significant improvement on HIV subjects survival. Thus, bone changes related to HIV became an important aspect of these individuals. HIV affects bone remodeling causing bone fragility. In addition, antiretroviral therapy may also negatively affect bone metabolism. Several studies describe an increased incidence of fractures in these patients when compared with controls without the disease. The European Society of AIDS (EACS), and other societies, have included guidance on management of osteoporosis in HIV-infected patients emphasizing the identification of patients with low bone mass. Supplementation of calcium and vitamin D and the use of alendronate in these individuals should be recommended on a case base.

Lower peak bone mass and abnormal trabecular and cortical microarchitecture in young men infected with HIV early in life

INTRODUCTION

HIV infection and antiretroviral therapy (ART) early in life may interfere with acquisition of peak bone mass, thereby increasing fracture risk in adulthood.

METHODS

We conducted a cross-sectional study of dual-energy X-ray absorptiometry (DXA) and high-resolution peripheral quantitative computed tomography (HR-pQCT) in 30 HIV-infected African-American or Hispanic Tanner stage 5 men aged 20-25 on ART (15 perinatally infected and 15 infected during adolescence) and 15 HIV-uninfected controls.

RESULTS

HIV-infected men were similar in age and BMI, but were more likely to be African-American (P = 0.01) than uninfected men. DXA-derived areal bone mineral density (aBMD) Z-scores were 0.4-1.2 lower in HIV-infected men at the spine, hip, and radius (all P < 0.05). At the radius and tibia, total and trabecular volumetric BMD (vBMD), and cortical and trabecular thickness were between 6 and 19% lower in HIV-infected than uninfected men (P <0.05). HIV-infected men had dramatic deficiencies in plate-related parameters by individual trabeculae segmentation (ITS) analyses and 14-17% lower bone stiffness by finite element analysis. Differences in most HR-pQCT parameters remained significant after adjustment for race/ethnicity. No DXA or HR-pQCT parameters differed between men infected perinatally or during adolescence.

CONCLUSION

At an age by which young men have typically acquired peak bone mass, HIV-infected men on ART have lower BMD, markedly abnormal trabecular plate and cortical microarchitecture, and decreased whole bone stiffness, whether infected perinatally or during adolescence. Reduced bone strength in young adults infected with HIV early in life may place them at higher risk for fractures as they age.

Weight and lean body mass change with antiretroviral initiation and impact on bone mineral density

OBJECTIVE

To compare the effect that initiating different antiretroviral therapy (ART) regimens has on weight, BMI, and lean body mass (LBM) and explore how changes in body composition are associated with bone mineral density (BMD).

METHODS

A5224s was a sub-study of A5202, a prospective trial of 1857 ART-naive participants randomized to blinded abacavir-lamivudine (ABC/3TC) or tenofovir DF-emtricitabine (TDF/FTC) with open-label efavirenz (EFV) or atazanavir-ritonavir (ATV/r). All participants underwent dual-energy absorptiometry (DXA) and abdominal computed tomography for body composition. Analyses used two-sample t-tests and linear regression.

RESULTS

A5224s included 269 participants: 85% men, 47% white non-Hispanic, median age 38 years, HIV-1 RNA 4.6 log10 copies/ml, and CD4 cell count 233 cells/μl. Overall, significant gains occurred in weight, BMI, and LBM at 96 weeks post-randomization (all P<0.001). Assignment to ATV/r (vs. EFV) resulted in significantly greater weight (mean difference 3.35 kg) and BMI gain (0.88 kg/m; both P=0.02), but not LBM (0.67 kg; P=0.15), whereas ABC/3TC and TDF/FTC were not significantly different (P≥0.10). In multivariable analysis, only lower baseline CD4 cell count and higher HIV-1 RNA were associated with greater increase in weight, BMI, or LBM. In multivariable analyses, increased LBM was associated with an increased hip BMD.

CONCLUSION

ABC/3TC vs. TDF/FTC did not differ in change in weight, BMI, or LBM; ATV/r vs. EFV resulted in greater weight and BMI gain but not LBM. A positive association between increased LBM and increased hip BMD should be further investigated through prospective interventional studies to verify the impact of increased LBM on hip BMD.

Long-term body composition and metabolic changes in HIV-infected children switched from stavudine to tenofovir and from protease inhibitors to efavirenz

This is an 8-year cohort study of 24 HIV-infected patients aged 5-17 years to assess body composition and metabolic changes after switching from lamivudine + stavudine (d4T) + protease inhibitors (PI) to lamivudine + tenofovir (TDF) + efavirenz (EFV). Body composition (dual-energy X-ray absorptiometry) and cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, glucose and insulin were measured annually. Linear mixed models and generalized linear mixed models were used to evaluate time changes of the outcome of interest. Body mass index increased linearly by 0.3 kg/m(2)/year (p < 0.001); waist circumference increased non-linearly from 68 to 74 cm (p = 0.004 for the linear term and p = 0.04 for the quadratic term). Percent body fat, percent trunk fat and percent bone mineral content increased linearly by 0.6%/year (p = 0.005), 1.2%/year (p < 0.001) and 0.02%/year (p = 0.04), respectively. Percent arm fat remained stable (p = 0.5), and percent leg fat decreased linearly by 1.2%/year (p < 0.001). The probability of low HDL was 0.2% at baseline and remained stable during the study. The probability of high triglycerides was 3% at baseline and increased linearly to become 11% at the 8th year of follow-up (p = ns). The probability of high glucose was 1% for the whole study duration.

CONCLUSIONS

patients, after switching from d4T to TDF and from PI to EFV, show most of the changes in anthropometry and body composition associated with normal growth and no frankly pathological change in metabolic parameters.

Incident fractures in HIV-infected individuals: a systematic review and meta-analysis

OBJECTIVE(S)

Some but not all studies indicate that individuals with HIV infection are at an increased risk of fracture. We systematically reviewed the literature to investigate whether incidence of fracture (both overall and fragility) differs between individuals with and without HIV.

DESIGN

A systematic review and meta-analysis.

METHODS

Medline, Scopus and the Cochrane Library databases for all studies ever published up to 28 September 2012 and electronically available conference abstracts from CROI, ASBMR, IAS and AIDS were searched. All studies reporting incidence of all fracture and fragility fracture in HIV-infected adults were included. A random effects model was used to calculate pooled estimates of incidence rate ratios (IRRs) for studies that presented data for HIV-infected and controls. For all studies, incidence rates of fracture and predictors of fracture among HIV-infected individuals were summarized.

RESULTS

Thirteen eligible studies were analysed, of which seven included controls. Nine studies reported all incident fractures and 10 presented incident fragility fractures. The pooled IRR was 1.58 [95% confidence interval (CI) 1.25-2.00] for all fracture and 1.35 (95% CI 1.10-1.65) for fragility fracture. Smoking, white race and older age were consistent predictors for fragility fractures.

CONCLUSION

Our results indicate that HIV infection is associated with a modest increase in incident fracture. Future research should focus on clarifying risk factors, designing appropriate interventions and the long-term implications of this increased risk for an ageing HIV-infected population.

Bone and vitamin D metabolism in HIV

Human immunodeficiency virus (HIV) infection has progressed to a chronic disease and HIV positive individuals are living longer lives. This has lead to an increase in morbidity and mortality due to secondary issues, one being HIV bone disease. HIV infected pediatric and adult populations have a greater incidence in reduction of BMD as compared to the controls. Osteoporosis has been reported to be present in up to 15 % of HIV positive patients. We are starting to understand the mechanism behind the changes in HIV bone disease. Viral proteins interfere with osteoblastic activity either by direct interaction or by the inflammatory process that they induce. Anti-viral management, including highly active antiretroviral therapy (HAART), protease inhibitors, and nucleoside/nucleotide reverse transcriptase inhibitors (NRTI) also are involved in disrupting proper bone metabolism. Vitamin D levels have strong correlation with bone disease in HIV patients, and are dependent not only to chronic disease state, but interaction of pharmacologic management and inflammatory process as well. Work up of the secondary causes of osteopenia and osteoporosis should be undertaken in all patients. DEXA scan is recommended in all post-menopausal women with HIV, all HIV infected men 50 years of age or older and in those with a history of fragility fractures regardless of age or gender. Preventive measures include adequate nutrition, calcium and Vitamin D intake daily, muscle strengthening and balance exercises to increase BMD and reduce fractures. Bisphosphonates are considered to be the first line for the treatment of HIV associated bone disease. This review will describe how the balanced mechanism of bone metabolism is interrupted by the HIV infection itself, the complications that arise from HIV/AIDS, and its treatment options.