Prevalence of low bone mineral density in men and women infected with human immunodeficiency virus 1 and a proposal for screening strategy

The Impact of Tenofovir Disoproxil Fumarate on Reduced Bone Mineral Density and Fractures in Liver Transplant Recipients

BACKGROUND

Tenofovir disoproxil fumarate (TDF) is associated with reduced bone density in patients with human immunodeficiency virus, but the effect of TDF on bone density in liver transplant (LT) recipients is unknown.

METHODS

We performed a single-center, retrospective study of LT recipients with hepatitis B taking TDF compared to a control group with non-hepatitis B virus viral hepatitis. The primary outcome was reduced bone density, defined as femoral neck or lumbar T-score less than -1. Other outcomes included mean T-score and fractures.

RESULTS

Three hundred ninety-three patients were studied: 52 patients in the TDF group and 341 patients in the control group; 64.3% patients in the TDF group had reduced bone density vs 71.4% in the control group (P = .58) before LT, compared to 75% and 81.5% (P = .57), respectively, after LT. Mean posttransplant lumbar T-scores were lower in the TDF group (-1.74 vs -0.75, P = .04). There was no difference between the 2 groups for the other outcomes. In a multivariate Cox proportional hazards model, TDF use did not affect the risk of post-LT reduced bone density (hazard ratio = 0.99; 95% confidence interval, 0.56-1.76; P = .97).

CONCLUSION

TDF use was not associated with reduced bone mineral density or increased rates of fractures in LT recipients compared to controls in this study.

Prevalence of and Risk Factors for Low Bone Mineral Density Assessed by Quantitative Computed Tomography in People Living With HIV and Uninfected Controls

BACKGROUND

Low bone mineral density (BMD) has been described in people living with HIV (PLWH). We examined the prevalence of low BMD measured by quantitative computed tomography (QCT), a method that allows 3-dimensional volumetric density measures at the thoracic spine, in well-treated PLWH and uninfected controls and assessed risk factors for reduced BMD.

METHODS

Cross-sectional study including 718 PLWH from the Copenhagen Co-Morbidity in HIV infection (COCOMO) study and 718 uninfected controls matched on age and sex from the Copenhagen General Population Study (CGPS). Trabecular BMD was determined by QCT.

RESULTS

Median BMD was 144.2 mg/cm in PLWH vs. 146.6 mg/cm in controls (P = 0.580). HIV status was not associated with BMD in univariable or multivariable linear analyses. However, a higher prevalence of very low BMD (T-score ≤ -2.5) was found in PLWH (17.2% vs. 11.0% in controls, P = 0.003). In unadjusted analysis, HIV was associated with very low BMD (odds ratio 1.68 [95% confidence interval: 1.24-2.27], P = 0.001), but this association was not significant after adjusting for age, sex, smoking, alcohol, body mass index, physical activity, and ethnicity. Previous AIDS-defining disease was associated with lower BMD, but no other associations with HIV-specific variables were identified.

CONCLUSION

Using QCT, we found a higher prevalence of very low BMD in PLWH than in controls. However, HIV status was not independently associated with BMD indicating that traditional risk factors contribute to the difference in prevalence of very low BMD. Focus on improvement of lifestyle factors, especially in PLWH with previous AIDS-defining disease, may prevent very low BMD in PLWH.

Osteopenia and osteoporosis among treatment-experienced people living with HIV

Introduction

Life expectancy of people living with human immunodeficiency (PLHIV) has increased mainly due to the accessibility and effectiveness of antiretroviral therapy (ART). However, adverse effects from long-term use of antiretrovirals, and the physiological changes associated with aging, may compromise the quality of life of PLHIV, in addition to causing new demands on the healthcare system.

Objectives

Estimate the frequency of osteoporosis and osteopenia in patients on prolonged ART and to verify their associated factors.

Methods

A cross-sectional study was conducted in Belo Horizonte, Minas Gerais, Brazil, from August 2017 to June 2018, in a sample of PLHIV (age ≥ 18 years) who started ART between 2001 and 2005. Data were collected through face-to-face interviews, physical evaluation, laboratory tests, and Dual-Energy X-Ray Absorptiometry Screening (DEXA). The outcome of interest was presence of bone alteration, defined as presence of osteopenia or osteoporosis in DEXA. The association between the explanatory variables and the event was assessed through odds ratio (OR) estimate, with 95% confidence interval (CI). Multiple logistic regression was performed to evaluate factors independently associated with bone alteration.

Results

Among 92 participants, 47.8% presented bone alteration (19.6% osteoporosis and 28.2% osteopenia). The variables that remained in the final logistic regression model were age ≥ 50 years (OR: 12.53; 95% CI: 4.37–35.90) and current alcohol use (OR: 2.63; 95% CI: 0.94–7.37).

Conclusions

This study showed a high frequency of bone changes, especially in PLHIV older than 50 years. This information is useful to stimulate the screening and timely intervention of this comorbidity of PLHIV on prolonged use of ART in order to prevent or minimize complications and new demands on the healthcare system.

Nevirapine Use Is Associated with Higher Bone Mineral Density in HIV-1 Positive Subjects on Long-Term Antiretroviral Therapy

We assessed bone mineral density (BMD) in a cohort of human immunodeficiency virus (HIV)-positive patients after a median of 11 years of combination antiretroviral therapy (cART) and evaluated the respective role of HIV infection and antiretroviral drugs (ARVs). A cross-sectional study of 162 participants (131 male) from the ANRS-C08 cohort was performed with bone dual-energy X-ray absorptiometry (DXA) scans and renal assessment. The window of exposure to ARVs was defined as an exposure of more than six cumulative months during the last 3 years before the DXA evaluation to account for a cumulative exposure that could affect bone remodeling. The association with low BMD (Z-score < -2) was assessed by a multiple logistic regression model. The study population was 50 years (median), hepatitis C virus (HCV) (18%), and hepatitis B virus (HBV) (8%) coinfection with HIV-RNA <50 c/mL in 89%, median CD4 of 619/mm³. Prevalence of low BMD was 18% in males and 6% in females. The factors associated with a Z-score < -2 in males were uric acid renal loss [adjusted odds ratio (aOR): 6.1; 95% confidence interval (CI): 1.2-31.5; p = .03], HCV coinfection (aOR: 4.0; 95% CI: 1.3-12.2; p = .02), and less frequent window of exposure to nevirapine (NVP) (aOR: 0.1; 95% CI: 0.02-0.6; p = .01). For the full study sample, there was a strong positive association between duration of exposure to NVP and lumbar spine Z-score (p = .004). HIV-positive patients exposed to long-term cART have a high incidence of low BMD. Tenofovir disoproxil fumarate and ritonavir-boosted protease inhibitors did not seem to be associated with increased risk of low BMD, whereas NVP exposure appeared to have an independent positive association.

Impact of Estimated Pre-Exposure Prophylaxis (PrEP) Adherence Patterns on Bone Mineral Density in a Large PrEP Demonstration Project

Bone mineral density (BMD) declines due to tenofovir-containing pre-exposure prophylaxis (PrEP) have varied among PrEP demonstration projects, potentially related to variable adherence. Characterization of BMD changes in highly adherent individuals, estimated via tenofovir-diphosphate (TFV-DP) levels in dried blood spots (DBS), can assist clinicians when counseling patients. Cisgender men who have sex with men and transwomen in the optional dual-energy X-ray absorptiometry (DXA) substudy of a large, international, open-label PrEP demonstration project, the iPrEx-open-label extension (OLE) study underwent DXA scans and DBS collection every 24 weeks, with average weekly dosing adherence patterns (2, 4, and 7 doses/week) estimated from validated TFV-DP cut-offs. The mean percent BMD change was estimated in strata of average weekly adherence by using a linear mixed-effects model to calculate the BMD decline in highly adherent individuals on PrEP for the first time. DXA/DBS data were available for 254 individuals over a median of 24 weeks in iPrEx-OLE from June 2011 to December 2013. The percent decline in spine BMD was monotonically associated with strata of increasing average weekly adherence (p < .001 trend); the p value for trends using hip BMD measurements was .07. Individuals with estimated daily adherence experienced a 1.2% decrease in spine BMD and a 0.5% drop in hip BMD. In highly adherent PrEP users, we found a lower-than-expected drop in BMD when compared with previous studies. This drop is likely not clinically significant for most PrEP users. However, for those at the highest risk of fracture who plan prolonged PrEP use, alternate PrEP strategies could be considered.

Vitamin D and Bone Mineral Density in HIV Newly Diagnosed Therapy-Naive Patients Without Any Secondary Causes of Osteoporosis

Bone loss and vitamin D deficiency are common in HIV patients. However, bone health status in newly diagnosed HIV patients has not been thoroughly described. Our aim was to assess the bone mineral density (BMD), bone resorption and vitamin D status in newly diagnosed HIV patients. A prospective observational study in HIV newly diagnosed therapy-naive persons. Patients with secondary causes of osteoporosis were excluded. Bone densitometry (DXA), a bone resorption marker (CTx), 25-hydroxyvitamin D (25OHD), CD4 count and HIV viral load (VL) were done in 70 patients. Vitamin D results were compared with a group of healthy volunteers. All patients were men, mean age 31 years (19-50). Low BMD (Z score ≤ 2.0) was found in 13%, all of them in lumbar spine, and in only one patient also in femoral neck. Bone resorption was high in 16%. One out of four participants had low BMD or high bone resorption. Vitamin D deficiency (25OHD < 20 ng/mL) was found in 66%. Mean 25OHD in patients was significantly lower than in healthy volunteers (p = 0.04). No associations were found between BMD, CTx, 25OHD and VL or CD4 count. We hypothesize that HIV infection negatively affects bone health based on the results we found among newly diagnosed, therapy-naive, HIV-infected patients, without any known secondary causes of osteoporosis. Low BMD or high bone resorption, are significantly prevalent in these patients. HIV-infected patients had a higher prevalence of vitamin D deficiency than controls, which was not correlated with CD4 count or VL.

The antiviral drug tenofovir, an inhibitor of Pannexin-1-mediated ATP release, prevents liver and skin fibrosis by downregulating adenosine levels in the liver and skin

Background

Fibrosing diseases are a leading cause of morbidity and mortality worldwide and, therefore, there is a need for safe and effective antifibrotic therapies. Adenosine, generated extracellularly by the dephosphorylation of adenine nucleotides, ligates specific receptors which play a critical role in development of hepatic and dermal fibrosis. Results of recent clinical trials indicate that tenofovir, a widely used antiviral agent, reverses hepatic fibrosis/cirrhosis in patients with chronic hepatitis B infection. Belonging to the class of acyclic nucleoside phosphonates, tenofovir is an analogue of AMP. We tested the hypothesis that tenofovir has direct antifibrotic effects in vivo by interfering with adenosine pathways of fibrosis using two distinct models of adenosine and A2AR-mediated fibrosis.

Methods

Thioacetamide (100mg/kg IP)-treated mice were treated with vehicle, or tenofovir (75mg/kg, SubQ) (n = 5–10). Bleomycin (0.25U, SubQ)-treated mice were treated with vehicle or tenofovir (75mg/kg, IP) (n = 5–10). Adenosine levels were determined by HPLC, and ATP release was quantitated as luciferase-dependent bioluminescence. Skin breaking strength was analysed and H&E and picrosirus red-stained slides were imaged. Pannexin-1expression was knocked down following retroviral-mediated expression of of Pannexin-1-specific or scrambled siRNA.

Results

Treatment of mice with tenofovir diminished adenosine release from the skin of bleomycin-treated mice and the liver of thioacetamide-treated mice, models of diffuse skin fibrosis and hepatic cirrhosis, respectively. More importantly, tenofovir treatment diminished skin and liver fibrosis in these models. Tenofovir diminished extracellular adenosine concentrations by inhibiting, in a dose-dependent fashion, cellular ATP release but not in cells lacking Pannexin-1.

Conclusions

These studies suggest that tenofovir, a widely used antiviral agent, could be useful in the treatment of fibrosing diseases.

Brief Report: Recovery of Bone Mineral Density After Discontinuation of Tenofovir-Based HIV Pre-exposure Prophylaxis

BACKGROUND

Oral tenofovir disoproxil fumarate (TDF) for HIV prevention and treatment is associated with decreases in bone mineral density (BMD). Previous reports suggest that these changes may be reversible after discontinuation of TDF.

SETTING

A metabolic substudy of 498 participants in a randomized, placebo-controlled HIV prevention trial of oral coformulated TDF with emtricitabine (TDF/FTC, Truvada) for HIV pre-exposure prophylaxis (PrEP) enrolling a global sample of men who have sex with men and trans women.

METHODS

Participants underwent dual X-ray absorptiometry to quantify bone mineral density (BMD) in the hip and spine during PrEP and at 2 visits after stopping (median of 23 and 79 weeks post-PrEP, respectively). Results are stratified by pharmacologic measure of TDF/FTC adherence.

RESULTS

There was no significant difference in change in hip/spine BMD at any time point between placebo and those with low adherence. Adherent participants had a mean (standard error) BMD change at TDF/FTC discontinuation of -1.02% (0.24) in the hip and -1.84% (0.36) in the spine. After stop, annualized BMD increases of 1.13% per year (0.27) in hip and 1.81% per year (0.36) in spine BMD were observed in adherent participants compared with 0.19% (0.16) and 0.74% (0.21) in the placebo group, respectively (P = 0.003, both comparisons). On average, BMD returned to baseline levels by 1 year after PrEP stop. Recovery was consistent across age, baseline BMD z-score, and treatment duration.

CONCLUSIONS

Mean BMD returns to baseline levels within 12-18 months after TDF-based PrEP discontinuation in both hip and spine with consistency across participant subgroups.

CLINICAL TRIALS REGISTRATION

clinicaltrials.gov NCT00458393.

How to predict the risk of fracture in HIV?

PURPOSE OF REVIEW

Skeletal fractures are more common in HIV, and impact the medical, functional and economic status of frequently vulnerable patients. Identifying asymptomatic patients with low bone mineral density (BMD)/osteoporosis requiring intervention can be expected to reduce fracture risk and complications. Clinical tools are available to determine fracture risk in the general population and are being evaluated in HIV patients. The FRAX calculator, incorporating demographics and risk factors for osteoporosis, with or without BMD results, has been investigated most often in HIV patients.

RECENT FINDINGS

The few published studies that have calculated the 10-year FRAX risk for both major osteoporosis and hip fractures without BMD generally show limited precision in predicting the presence of osteoporosis severe enough to initiate treatment. It remains uncertain whether using HIV as a secondary risk factor and adding dual X-ray absorptiometry (DXA)-BMD information improves case-finding compared with using DXA results only. Not incorporating risks relevant to aging HIV patients such as antiretroviral exposure, hepatitis C virus coinfection and history of falls is other potential limitation.

SUMMARY

Accurate screening tools using clinical risk factors alone to determine fracture risk in HIV are not yet available. Further research and validation studies are necessary.

Osteoarticular manifestations associated with HIV infection

About 150,000 people are HIV-positive in France, and the number of new cases is estimated at 7000-8000 per year, with no tendency to diminish over time. Admissions of HIV-positive patients have been decreasing, in contrast, since 2008, reflecting the dramatic improvements in quality of life and survival provided by triple antiretroviral regimens. HIV infection is now a chronic disease that exposes patients to the virus and antiretroviral drugs for many years. One consequence has been the emergence of new health conditions in HIV-positive patients, such as tumors, cardiovascular disease, and osteoarticular complications. These epidemiological and clinical changes have made it necessary for rheumatologists to learn about the osteoarticular abnormalities associated with the HIV, which they are likely to encounter at some point during their everyday practice. Osteoporosis is one such abnormality, and this review article starts with a discussion of the literature on this topic. Bone loss is common, chiefly in males. Multiple factors are involved. Studies have demonstrated an increase in the fracture risk and, consequently, recommendations about the screening and treatment of osteoporosis have been issued. The focus of this review article then turns to the other rheumatic manifestations seen in HIV-positive patients, including osteomalacia, avascular necrosis, and inflammatory joint disease. Osteoarticular pain is frequently reported by HIV-positive patients. Identifying the cause is essential to determine the best treatment strategy. Interestingly, immunosuppressant drugs, and even biotherapies, have shown a good safety profile in these immunodeficient patients.

Increased risk of hip fracture associated with dually treated HIV/hepatitis B virus coinfection

HIV and hepatitis B virus (HBV) infections are each associated with reduced bone mineral density, but it is unclear whether HIV/HBV coinfection is associated with an increased risk of fracture. We determined whether dually treated HIV/HBV patients had a higher incidence of hip fracture compared to treated HBV-monoinfected, antiretroviral therapy (ART)-treated HIV-monoinfected and HIV/HBV-uninfected patients. We conducted a cohort study among 4156 dually treated HIV/HBV-coinfected, 2053 treated HBV-monoinfected, 96,253 ART-treated HIV-monoinfected, and 746,794 randomly sampled uninfected persons within the US Medicaid populations of California, Florida, New York, Ohio and Pennsylvania (1999-2007). Coinfected patients were matched on propensity score to persons in each comparator cohort. Weighted survival models accounting for competing risks were used to estimate cumulative incidences and hazard ratios (HRs) with 95% confidence intervals (CIs) of incident hip fracture for dually treated coinfected patients compared to (i) HBV-monoinfected receiving nucleos(t)ide analogue or interferon alfa therapy, (ii) HIV-monoinfected on ART and (iii) uninfected persons. Dually treated coinfected patients had a higher cumulative incidence of hip fracture compared to ART-treated HIV-monoinfected (at 5 years: 1.70% vs 1.24%; adjusted HR, 1.37 [95% CI, 1.03-1.83]) and uninfected (at 5 years: 1.64% vs 1.22%; adjusted HR, 1.35 [95% CI, 1.03-1.84]) persons. The cumulative incidence of hip fracture was higher among coinfected than treated HBV-monoinfected patients (at 5 years: 0.70% vs 0.27%), but this difference was not statistically significant in competing risk analysis (adjusted HR, 2.62 [95% CI, 0.92-7.51]). Among Medicaid enrollees, the risk of hip fracture was higher among dually treated HIV/HBV-coinfected patients than ART-treated HIV-monoinfected and uninfected persons.

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.

Antiretroviral therapy: when to start

In this article, the scientific evidence and professional guidelines regarding the timing of antiretroviral therapy initiation are reviewed, with discussion of the increasingly persuasive evidence in favor of starting treatment early in the course of human immunodeficiency virus disease.

The effects of untreated and treated HIV infection on bone disease

PURPOSE OF REVIEW

Low bone mineral density (BMD) is common in those with HIV, associated with higher bone turnover and a higher prevalence of fractures. This review explores low BMD in HIV, focusing on underlying mechanisms and relationships between low BMD and HIV infection, immune dysfunction, and antiretroviral therapy (ART).

RECENT FINDINGS

Greater reductions in BMD accompanying reductions in HIV viremia at initiation of first-line or second-line ART suggest an important role for immune- or viral-mediated mechanisms in its pathogenesis.

SUMMARY

As bone metabolism is part-regulated by T cells and B cells, we propose that earlier initiation of ART at higher CD4 T-cell counts may attenuate BMD loss by abrogating immune- and viral-mediated disturbances in bone metabolism that accompany ART initiation. Further pathogenesis-based research is required in this field, focusing on the complex interaction between virus, immune system, ART, and bone metabolism.

Osteoporosis in Human Immunodeficiency Virus Patients - An Emerging Clinical Concern

The advent of highly active anti-retroviral therapy (HAART) has significantly improved the survival of human immunodeficiency virus (HIV)-infected patients transforming the HIV infection from a fatal illness into a manageable chronic disease. As the number of older HIV-infected individuals increases, several ageing-related co-morbidities including osteopenia/osteoporosis and fractures have emerged. Patients exposed to HIV infection and its treatment may develop fragility fractures with potential significant impact on quality of life and survival. However, the awareness of HIV-related skeletal fragility is still relatively low and most HIV-infected patients are not investigated for osteoporosis and treated with anti-osteoporotic drugs in daily clinical practice. This article reviews the literature data on osteoporosis and osteopenia in HIV infection, focusing on the pathophysiological, clinical and therapeutic aspects of fragility fractures.

HIV and ageing: what the geriatrician needs to know

The transformation of human immunodeficiency virus (HIV) from a rapidly fatal disease to a chronic manageable illness has resulted in annual increases in the numbers of people living with HIV. The HIV cohort is therefore ageing, with numbers of older adults with HIV climbing, through both prolonged survival and late acquisition of the disease. Associated with ageing is an accumulation of HIV-associated non-AIDS related co-morbidities, creating a complex patient group affected by multi-morbidity along with polypharmacy, functional decline and complex social issues. With this in mind, this review seeks to explore areas where HIV (diagnosed or undetected) may impact on the work of clinical geriatricians.

Changes in bone mineral density over a 2-year period in HIV-1-infected men under combined antiretroviral therapy with osteopenia

OBJECTIVE

Although osteopenia is common in HIV-infected patients, there is by now limited data on the evolution of bone mineral density in this population. We aimed to evaluate the course of osteopenia over a 2-year period in HIV-1-infected men, and to identify risk factors for abnormal bone mineral density (BMD) decline.

METHODS

HIV-1-infected men on combined antiretroviral therapy (cART) screened in the ANRS 120 Fosivir trial, diagnosed with low BMD (-2.5 ≤T-score <-1), not receiving antiosteoporotic agents, with sequential dual-energy-X ray-absorptiometry (DXA) available at baseline were eligible for this study and had a second DXA performed between months 24 and 36.

RESULTS

We enrolled 94 men with a median age of 46 years [interquartile range (IQR), 41-53], BMI 22 kg/m² (21-25) and a CD4 cell nadir of 164/μl (69-261). They were receiving cART for a median of 7.5 years (5.8-9.5). Over a median interval of 2.6 years (2.3-2.9) between the two DXA tests, the mean change in BMD was -0.5 ± 1.7% per year (P = 0.010) at the lumbar spine and -0.4 ± 1.8% per year (P = 0.033) at the hip. BMD fell by more than the smallest detectable difference (SDD) in, respectively, 25.5 and 27.7% of patients at the lumbar spine and hip. Tenofovir (TDF) exposure was independently associated with a larger decline in BMD at both sites [lumbar spine, OR = 2.4 (1.2-4.9); hip, OR = 2.8 (1.3-5.9)].

CONCLUSION

Although osteopenia overall modestly changes over 2 years in long-term cART-treated patients, a quarter of patients experienced a significant loss (>1 SDD) associated with TDF exposure.