Trabecular bone score (TBS) is associated with sub-clinical vertebral fractures in HIV-infected patients

Guidelines for fracture risk assessment and management of osteoporosis in postmenopausal women and men above the age of 50 in Qatar

We present comprehensive guidelines for osteoporosis management in Qatar. Formulated by the Qatar Osteoporosis Association, the guidelines recommend the age-dependent Qatar fracture risk assessment tool for screening, emphasizing risk-based treatment strategies and discouraging routine dual-energy X-ray scans. They offer a vital resource for physicians managing osteoporosis and fragility fractures nationwide.

PURPOSE

Osteoporosis and related fragility fractures are a growing public health issue with an impact on individuals and the healthcare system. We aimed to present guidelines providing unified guidance to all healthcare professionals in Qatar regarding the management of osteoporosis.

METHODS

The Qatar Osteoporosis Association formulated guidelines for the diagnosis and management of osteoporosis in postmenopausal women and men above the age of 50. A panel of six local rheumatologists who are experts in the field of osteoporosis met together and conducted an extensive review of published articles and local and international guidelines to formulate guidance for the screening and management of postmenopausal women and men older than 50 years in Qatar.

RESULTS

The guidelines emphasize the use of the age-dependent hybrid model of the Qatar fracture risk assessment tool for screening osteoporosis and risk categorization. The guidelines include screening, risk stratification, investigations, treatment, and monitoring of patients with osteoporosis. The use of a dual-energy X-ray absorptiometry scan without any risk factors is discouraged. Treatment options are recommended based on risk stratification.

CONCLUSION

Guidance is provided to all physicians across the country who are involved in the care of patients with osteoporosis and fragility fractures.

Evaluation of bone mineral density, microarchitecture, and detection of fractures on young patients living with human immunodeficiency virus: when and how to screen?

PURPOSE

People living with the human immunodeficiency virus (PLWH) developed higher life expectancy along with chronic bone disease over the past years. Our purpose is to evaluate bone mineral density, bone microarchitecture and fractures in young PLWH and understand the disease's contribution to bone derangements and fracture risk.

METHODS

Eighty-one HIV-infected and 54 control young (20-50 years) male and female subjects were enrolled in this study. Methods for patient evaluation included DXA-VFA (dual energy X-rays and vertebral fracture assessment), HR-pQCT (high resolution peripheral quantitative computed tomography), biochemistry and FRAX.

RESULTS

Fifty participants from each group completed all exams. Median age was 40 (25-49) vs. 36.5 (22-50) for the HIV and control groups, respectively (p 0.120). Ethnicity, body mass index, serum phosphorus, 25-hydroxyvitamin D, PTH and CTX were similar between groups, although ALP and OC suggested higher bone turnover in PLWH. VFA identified morphometric vertebral fractures in 12% of PLWH. PLWH had lower values for lumbar spine areal BMD and Z score, volumetric BMD, trabecular bone fraction (BV/TV) and trabecular number measured at the distal tibia by HR-pQCT; as a consequence, trabecular separation and heterogeneity were higher (all p < 0.05). The FRAX-estimated risk for hip and major osteoporotic fractures was statistically higher in PLWH (p < 0.001).

CONCLUSION

Our results confirm severe bone impairment and fractures associated with HIV in young patients. Thus, we developed a screening protocol for young PLWH to detect bone fragility, reduce skeletal disease progression and morbimortality, decrease fracture risk, and increase quality of life.

Update on the clinical use of trabecular bone score (TBS) in the management of osteoporosis: results of an expert group meeting organized by the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO), and the International Osteoporosis Foundation (IOF) under the auspices of WHO Collaborating Center for Epidemiology of Musculoskeletal Health and Aging

PURPOSE

Trabecular bone score (TBS) is a grey-level textural measurement acquired from dual-energy X-ray absorptiometry lumbar spine images and is a validated index of bone microarchitecture. In 2015, a Working Group of the European Society on Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) published a review of the TBS literature, concluding that TBS predicts hip and major osteoporotic fracture, at least partly independent of bone mineral density (BMD) and clinical risk factors. It was also concluded that TBS is potentially amenable to change as a result of pharmacological therapy. Further evidence on the utility of TBS has since accumulated in both primary and secondary osteoporosis, and the introduction of FRAX and BMD T-score adjustment for TBS has accelerated adoption. This position paper therefore presents a review of the updated scientific literature and provides expert consensus statements and corresponding operational guidelines for the use of TBS.

METHODS

An Expert Working Group was convened by the ESCEO and a systematic review of the evidence undertaken, with defined search strategies for four key topics with respect to the potential use of TBS: (1) fracture prediction in men and women; (2) initiating and monitoring treatment in postmenopausal osteoporosis; (3) fracture prediction in secondary osteoporosis; and (4) treatment monitoring in secondary osteoporosis. Statements to guide the clinical use of TBS were derived from the review and graded by consensus using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach.

RESULTS

A total of 96 articles were reviewed and included data on the use of TBS for fracture prediction in men and women, from over 20 countries. The updated evidence shows that TBS enhances fracture risk prediction in both primary and secondary osteoporosis, and can, when taken with BMD and clinical risk factors, inform treatment initiation and the choice of antiosteoporosis treatment. Evidence also indicates that TBS provides useful adjunctive information in monitoring treatment with long-term denosumab and anabolic agents. All expert consensus statements were voted as strongly recommended.

CONCLUSION

The addition of TBS assessment to FRAX and/or BMD enhances fracture risk prediction in primary and secondary osteoporosis, adding useful information for treatment decision-making and monitoring. The expert consensus statements provided in this paper can be used to guide the integration of TBS in clinical practice for the assessment and management of osteoporosis. An example of an operational approach is provided in the appendix. This position paper presents an up-to-date review of the evidence base, synthesised through expert consensus statements, which informs the implementation of Trabecular Bone Score in clinical practice.

Gender and sex considerations in HIV and bone health

PURPOSE OF REVIEW

People with HIV (PWHIV) are at increased risk for osteoporosis and fractures, because of the effects of HIV and inflammation and antiretroviral therapy (ART) initiation as well as traditional risk factors. This review from recent literature focuses on sex differences in rates of bone disease, risk of fractures, and effects of ART.

RECENT FINDINGS

Women with HIV in resource-constrained settings experience bone loss because of the additive effect of initiating TDF-containing ART during pregnancy, lactation, and menopause. Children and adolescents experience lower bone accrual during the pubertal growth years. There has been less focus on bone health in recent trials of ART containing tenofovir alafenamide and/or integrase inhibitors. Very few clinical trials or studies compare sex-specific changes in inflammation, immune activation, response to ART and bone turnover or change in BMD resulting in significant knowledge gaps.

SUMMARY

More data is needed to determine changes in prevalence of osteopenia, osteoporosis, and fractures in the era of immediate initiation of ART at high CD4 cell counts and the use of more bone-friendly ART. The long-term effects of ART and low bone mass on fractures in the ageing population of PWHIV is yet to be realized.

Bone Quality in Relation to HIV and Antiretroviral Drugs

PURPOSE OF REVIEW

People living with HIV (PLWH) are at an increased risk for osteoporosis, a disease defined by the loss of bone mineral density (BMD) and deterioration of bone quality, both of which independently contribute to an increased risk of skeletal fractures. While there is an emerging body of literature focusing on the factors that contribute to BMD loss in PLWH, the contribution of these factors to bone quality changes are less understood. The current review summarizes and critically reviews the data describing the effects of HIV, HIV disease-related factors, and antiretroviral drugs (ARVs) on bone quality.

RECENT FINDINGS

The increased availability of high-resolution peripheral quantitative computed tomography has confirmed that both HIV infection and ARVs negatively affect bone architecture. There is considerably less data on their effects on bone remodeling or the composition of bone matrix. Whether changes in bone quality independently predict fracture risk, as seen in HIV-uninfected populations, is largely unknown. The available data suggests that bone quality deterioration occurs in PLWH. Future studies are needed to define which factors, viral or ARVs, contribute to loss of bone quality and which bone quality factors are most associated with increased fracture risk.

Changes in trabecular bone score and bone mineral density in Chinese HIV-Infected individuals after one year of antiretroviral therapy

OBJECTIVE

Human immunodeficiency virus (HIV) infection and antiretroviral therapy (ART) have been associated with reduced bone mineral density (BMD) in persons with HIV (PWH). BMD provides information only about bone mineral quantity. Trabecular bone score (TBS) is a noninvasive tool that estimates bone microarchitecture. The aim of this study is to measure BMD and TBS of Chinese PWH after one-year ART.

METHODS

We designed a retrospective study of adult Chinese PWH. Patients with a dual-energy X-ray absorptiometry (DXA) scan prior to ART initiation, and again 48 weeks later were included. Information regarding demographic and clinical history, HIV treatment history, BMD and TBS were collected. We analyzed differences in BMD and TBS over 48 weeks and associations between key risk factors and changes in BMD and TBS.

RESULTS

Our study included 233 ​PWH (mean age ​= ​36.6 ​± ​11.1 years). Before ART initiation, 19.3% of PWH had normal BMD but abnormal TBS. Both BMD and TBS decreased after one-year ART. TDF and LPV/r-containing regimens were associated with greater declines in BMD at different site. Traditional risk factors such as old age, low BMI and female sex were associated with lower baseline TBS. Greater change in TBS over one year was associated with lower BMI and lower baseline CD4+ cell count, but unlike BMD measures, it was not correlated with treatment with TDF and LPV/r in our study population.

CONCLUSIONS

We present the first longitudinal analysis of change in TBS over 48 weeks compared with BMD among Asian PWH receiving ART. Before ART initiation, approximately 20% of PWH with impaired bone microarchitecture would not have been identified if DXA were used alone to assess for bone damage. Both BMD and TBS decreased after one-year ART. Change in TBS was not associated with different antiretroviral agents.

THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE

The trabecular microarchitecture measured indirectly by TBS may provide clinicians additional information about bone damage in PWH.

Long-term trabecular bone score and bone mineral density changes in Chinese antiretroviral-treated HIV-infected individuals

This is the first 5-year analysis among persons with HIV (PWH) that reports both trabecular bone score (TBS), which is a novel index that estimates bone microarchitecture, and bone mineral density (BMD) over time to evaluate the long-term impact of antiretroviral therapy (ART) on bone health.

PURPOSE

HIV infection and antiretroviral therapy (ART) have been associated with decreased bone mineral density (BMD). This study aims to evaluate long-term changes in trabecular bone score (TBS), a novel index that estimates bone microarchitecture, and BMD among Chinese persons with HIV (PWH) treated with ART.

METHODS

We conducted a retrospective chart review of adult PWH at a large tertiary care hospital in China. Patients who had a DXA scan prior to ART and at least one follow-up DXA after ART initiation were included. Subgroup analyses examined the TBS and BMD changes in patients who switch from a non-TDF-containing regimen to one containing TDF, as compared to those who did not switch.

RESULTS

Four hundred fifty-nine PWH were included. Among 68 patients ≥ 50 years, 13 patients (19.1%) had a normal BMD but partially degraded or degraded TBS. The mean percent decrease in lumbar spine (LS) BMD nadired at 48 weeks after ART initiation and then gradually improved. Percent decrease in femoral neck (FN) and total hip (TH) BMD nadired at 96 weeks and remained stably low thereafter. After switch to a TDF-containing regimen, only percent change in TH BMD was significant (-3.2%, p = 0.006). In the regression analyses, switch to a TDF-containing regimen was not associated with long-term change in TBS or BMD.

CONCLUSION

This is the first study among PWH to evaluate the long-term impact of ART on TBS and BMD. At baseline, approximately 20% of patients had a normal BMD but impaired bone microstructure based upon TBS. For patients with 5 years of exposure to ART, there is a stabilization of TBS and BMD after initial nadir in the first 144 weeks. However, FN BMD, TH BMD, and TBS remained low at 5 years relative to baseline.

Ability of FRAX Sri Lanka adjusted for trabecular bone score to discriminate between postmenopausal women with a recent fracture and without a fracture

Objectives

We evaluated the ability of fracture risk assessment tool (FRAX) Sri Lanka to discriminate between women with a recent fracture and without a fracture, when trabecular bone score (TBS) is added to the calculation.

Methods

We studied 394 women without previous fractures and 87 women who underwent dual energy X-ray absorptiometry within 3 months after the first fragility fracture. Fracture probabilities (FP) were estimated with and without TBS using Sri Lankan FRAX model and their ability to discriminate those with and without fracture was tested.

Results

Women without fractures had higher bone mineral densities (BMDs) and lower FPs, compared to those with a recent fracture. Area under curves of receiver operating characteristic for FPs unadjusted were not different from those adjusted for TBS. The odd ratios of FPs unadjusted were not different from those of adjusted. The FPs estimated with TBS were higher, hence the intervention thresholds (ITs) were higher compared to FPs estimated without TBS. Thirty-two percent of women without previous fracture were above the ITs and the inclusion of TBS increased this to 36%. The integrated discriminatory index analysis showed a 8% increase in the discriminatory slope.

Conclusions

The inclusion of TBS to Sri Lankan FRAX did not show an added advantage in discriminating between postmenopausal women with a recent fracture and without a fracture. TBS inclusion in fracture risk calculation among those without previous fractures, however, showed a marginal increase in the number of women above ITs.

People living with HIV and fracture risk

PLHIV have an increased risk of osteoporosis and fractures when compared with people of the same age and sex. In this review, we address the epidemiology and the pathophysiology of bone disease and fractures in PLHIV. The assessment of fracture risk and fracture prevention in these subjects is also discussed. The spectrum of HIV-associated disease has changed dramatically since the introduction of potent antiretroviral drugs. Today, the survival of people living with HIV (PLHIV) is close to that of the general population. However, the longer life-span in PLHIV is accompanied by an increased prevalence of chronic diseases. Detrimental effects on bone health are well recognised, with an increased risk of osteoporosis and fractures, including vertebral fractures, compared to the general population. The causes of bone disease in PLHIV are not fully understood, but include HIV-specific risk factors such as use of antiretrovirals and the presence of chronic inflammation, as well as traditional risk factors for fracture. Current guidelines recommend the use of FRAX to assess fracture probability in PLHIV age ≥ 40 years and measurement of bone mineral density in those at increased fracture risk. Vitamin D deficiency, if present, should be treated. Bisphosphonates have been shown to increase bone density in PLHIV although fracture outcomes are not available.

Bone fracture among people living with HIV: A systematic review and meta-regression of prevalence, incidence, and risk factors

Introduction

People living with HIV (PLWH) had a higher prevalence and incidence rate of bone fracture compared to general population. Although several studies have explored this phenomenon, the prevalence and incidence rate of fracture were varied.

Objective

The aim of the study is to determine and analyze the pooled prevalence, incidence rate of fracture and fracture risk factors among people living with HIV (PLWH).

Methods

PubMed, Cochrane Library, CINAHL with full Text, and Medline databases for studies published up to August 2019 were searched. Studies reporting the prevalence or incidence of fracture among PLWH were included. Study quality was assessed using the Joanna Briggs Institute (JBI) appraisal tool. A meta-analysis with random-effects model was performed to determine pooled estimates of prevalence and incidence rates of fracture. A meta-regression was performed to determine the source of heterogeneity.

Results

The pooled estimated prevalence of fracture among PLWH was 6.6% (95% CI: 3.8–11.1) with pooled odds ratio of 1.9 (95%CI: 1.1–3.2) compared to the general population. The pooled estimates of fracture incidence were 11.3 per 1000 person-years (95% CI: 7.9–14.5) with incidence rate ratio (IRR) of 1.5 (95% CI: 1.3–1.8) compared to the general population. Risk factors for fracture incidence were older age (aHR 1.4, 95% CI: 1.3–1.6), smoking (aHR 1.3, 95% CI: 1.1–1.5), HIV/HCV co-infection (aHR 1.6, 95% CI: 1.3–1.9), and osteoporosis (aHR 3.3, 95% CI: 2.2–5.1).

Conclusions

Our finding highlights a higher risk of fracture among PLWH compared to the general population. Osteoporosis, smoking and HIV/HCV coinfection as the significant modifiable risk factors should be prioritized by the HIV health providers when care for PLWH.

CD4 T cell count is inversely associated with lumbar spine bone mass in HIV-infected men under the age of 50 years

HIV-infected men under the age of 50 years had a lower bone mass compared to that of HIV-uninfected men. Lower CD4 T cell counts, independent of whether antiretroviral therapy (ART) was used, were associated with lower BMD. HIV-infected patients with low CD4 T cell counts may need follow-up and intervention regarding bone health, including younger patients.

INTRODUCTION

HIV-infected patients have a low bone mineral density (BMD) owing to multifactorial interaction between common osteoporosis risk factors and HIV-related factors, including chronic inflammation and ART. Although HIV infection and ART might affect bone metabolism, little data is available for patients aged under 50 years. We aimed to investigate the association of HIV infection-induced low CD4 T cell counts and ART with BMD in men aged under 50 years.

METHODS

We performed an age- and body mass index-matched case-control study. BMD values of HIV-infected and HIV-uninfected men (< 50 years) were compared, and HIV-infected men were stratified by CD4 T cell counts and ART use.

RESULTS

After adjusting confounders, HIV-infected men with CD4 T cell counts ≥ 500 cells/μL (n = 28) and < 500 cells/μL (n = 139) had lower BMD at the femoral neck (FN, p < 0.001) and total hip (TH, p < 0.001) than HIV-uninfected men (n = 167). HIV-infected men with CD4 T cell counts < 500/μL had lower BMD at the lumbar spine (LS, p = 0.034) than those with counts of ≥ 500 cells/μL, but not at FN and TH. The CD4 T cell count (γ = 0.169, p = 0.031) was positively correlated with BMD at LS. There was no significant difference in the BMD (p = 0.499-> 0.999) between the ART-naïve (n = 75) and ART-user group (n = 92).

CONCLUSIONS

Despite their relatively younger age, HIV-infected men had a lower BMD than HIV-uninfected men. Lower CD4 T cell counts, irrespective of ART, might result in lower bone mass.

Diagnosis, prevention, and treatment of bone fragility in people living with HIV: a position statement from the Swiss Association against Osteoporosis

Life expectancy of people living with HIV (PLWH) is reaching similar length as in the general population. Accordingly, age-related comorbidities, including osteoporosis, are increasing. Fracture risk is higher and increases approximately 10 years earlier in PLWH. Classical risk factors of bone fragility are highly prevalent in PLWH but factors specific for HIV infection itself and the type of antiretroviral therapy (ART) (triple combination antiretroviral therapy) regimen (especially tenofovir and protease inhibitors) also contribute to bone loss. The majority of bone loss occurs during virus activity and at initiation of ART (immune reconstitution) and is associated with an increase of bone resorption (upregulation RANKL). Recent data indicate that calcium and vitamin D supplements as ART initiation lower BMD loss. The reduction of tenofovir plasma concentrations with tenofovir alafenamide attenuates BMD loss but it remains unknown whether it will contribute to reduce fracture risk. Hence, special considerations for the management of bone fragility in PLWH are warranted. Based on the current state of epidemiology and pathophysiology of osteoporosis in PLWH, we provide the consensus of the Swiss Association against Osteoporosis on best practice for diagnosis, prevention, and management of osteoporosis in this population. Periodic assessment of fracture risk is indicated in all HIV patients and general preventive measures should be implemented. All postmenopausal women, men above 50 years of age, and patients with other clinical risk for fragility fractures qualify for BMD measurement. An algorithm clarifies when treatment with bisphosphonates and review of ART regimen in favour of more bone-friendly options are indicated.

Relationship Between Vertebral Fractures, Bone Mineral Density, and Osteometabolic Profile in HIV and Hepatitis B and C-Infected Patients Treated With ART

Objective: The purpose of our study was to evaluate the alterations of bone metabolism and the prevalence of vertebral fractures in the population with HIV and hepatitis B and C seropositivity in treatment with antiretroviral drugs (HAART). Methods: We selected 83 patients with diagnosis of HIV, HBV, HCV infection. In all these patients biochemical examinations of phospho-calcium metabolism and a densitometry of lumbar spine were performed. We also evaluated lateral spine X-rays in order to analyze the presence of vertebral deformities and to define their severity. As a control group we analyzed the prevalence of vertebral fractures in a group of 40 non-infectious patients. Results: We selected 82 seropositive patients, 46 males and 37 females, with a median age of 55 ± 10 years. Out of these patients, 55 were infected by HIV, 12 were infected by HBV, 11 presented HIV and HCV co-infection and 4 were HCV+. The prevalence of hypovitaminosis D in the studied population was 53%, while the prevalence of osteoporosis and osteopenia was 14 and 48%, respectively. The average T-score in the fractured population was -1.9 SD. The viral load and the CD4+ cell count were respectively, directly, and inversely correlated with the number and severity of vertebral fractures. Antiretroviral therapy regimen containing TDF and PI was a significant determinant of the presence of vertebral deformities. The use of these drugs was also associated with lower levels of vitamin D and higher bone turnover levels compared to other antiretroviral drugs. Conclusions: HIV patients suffer from bone fragility, particularly at spine, independently by the level of bone mineral density. In this population, the T-score threshold for the risk of fracture is higher than that usually used in general population. For this reason, it would be indicated to perform an X-ray of the spine in order to detect vertebral deformities even in patients with a normal or slighlty reduced bone mineral density.

HIV Infection Is Associated With Abnormal Bone Microarchitecture: Measurement of Trabecular Bone Score in the Women's Interagency HIV Study

OBJECTIVES

We compared skeletal microarchitecture using trabecular bone score (TBS) and evaluated relationships between change in TBS and lumbar spine (LS) bone mineral density (BMD) in women with and without HIV.

METHODS

Dual-energy X-ray absorptiometry was performed on 319 women with HIV and 118 without HIV in the Women's Interagency HIV Study at baseline and 2 and 5 years, to measure regional BMD and lean and fat mass. TBS was extracted from LS dual-energy X-ray absorptiometry images and examined continuously and categorically [normal (≥1.35), intermediate (1.20-1.35), or degraded (≤1.20) microarchitecture]. Pearson correlation and linear regression examined associations of TBS with regional BMD at baseline and over time.

RESULTS

Women with HIV were older (43 vs. 37 years), more likely to be postmenopausal (27% vs. 4%), have lower baseline total fat mass, trunk fat, and leg fat than uninfected women, degraded microarchitecture (27% vs. 9%, P = 0.001), and lower baseline mean TBS (1.3 ± 0.1 vs. 1.4 ± 0.1, P < 0.001). After adjusting for age, race, menopause status, and body mass index, TBS remained lower in women with HIV (P < 0.0001). Annual change in TBS correlated with LS BMD change among women with HIV (r = 0.36, P < 0.0001) and without HIV (r = 0.26, P = 0.02); however, mean % annual TBS change did not differ by HIV status (-1.0%/yr ± 2.9% for HIV+ vs. -0.8%/yr ± 1.7% for HIV-, P = 0.42).

CONCLUSIONS

Women with HIV have worse bone microarchitecture than uninfected women, but annual percent change in LS BMD or TBS was similar. Use of TBS as an adjunct to BMD to improve prediction of fragility fractures in women with HIV merits further study.

Improved fracture prediction using different fracture risk assessment tool adjustments in HIV-infected women

OBJECTIVES

A fracture risk assessment tool (FRAX) using clinical risk factors (CRFs) alone underestimates fracture risk in HIV-infected men. Our objective was to determine whether accuracy of FRAX would be improved by considering HIV as a cause of secondary osteoporosis, and further improved with addition of dual-energy X-ray absorptiometry parameters in HIV-infected women.

DESIGN

Subgroup analysis of Women's Interagency HIV Study.

METHODS

We included 1148 women (900 HIV-infected and 248 uninfected) over age 40 with data to approximate FRAX CRFs and 10-year observational data for incident fragility fractures; 181 (20%) HIV-infected women had dual-energy X-ray absorptiometry data. Accuracy of FRAX was evaluated by the observed/estimated ratios of fracture in four models: CRFs alone; CRFs with HIV included as a cause of secondary osteoporosis; CRFs and femoral neck bone mineral density (FN BMD); and CRFs, FN BMD and trabecular bone score.

RESULTS

FRAX using CRFs were less accurate in HIV-infected than uninfected women for major osteoporotic (observed/estimated ratio: 5.05 vs. 3.26, P < 0.001) and hip fractures (observed/estimated ratio: 19.78 vs. 7.94, P < 0.001), but improved when HIV was included as a cause of secondary osteoporosis. Among HIV-infected women, FRAX accuracy improved further with addition of FN BMD (observed/estimated ratio: 4.00) for hip fractures, but no further with trabecular bone score.

CONCLUSION

FRAX using CRFs alone underestimated fracture risk more in older HIV-infected women than otherwise similar uninfected women. Accuracy is improved when including HIV as a cause of secondary osteoporosis for both major osteoporotic and hip fractures, whereas addition of FN BMD only improved accuracy for hip fracture.

The Hidden Burden of Fractures in People Living With HIV

The survival of people living with human immunodeficiency virus (HIV) has increased markedly since the advent of antiretroviral therapy (ART). However, other morbidities have emerged, including osteoporosis. The estimated incidence of fractures at any site in people living with HIV ranges from 0.1 per 1000 person‐years to 8.4 per 1000 person‐years: at least twice that of people without HIV. This increased risk seems to be related to HIV itself and its treatment. Risk factors for bone disease in HIV‐positive (HIV⁺) subjects include both classical risk factors for osteoporosis and fracture and factors linked to HIV itself, such as inflammation, reconstitution syndrome, low CD4, ART, and co‐infection with hepatitis B and C viruses. The risk of fractures in these individuals can be at least partially assessed by measurement of BMD and the Fracture Risk Assessment Tool (FRAX™). Only alendronate and zoledronic acid have been studied in HIV⁺ individuals; both show beneficial effects on BMD, although data on fracture reduction are not available. © 2018 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

HIV and Vertebral Fractures: a Systematic Review and Metanalysis

The survival of HIV-infected patients has increased with the advent of antiretroviral therapy with the emergence of new comorbidities. Vertebral fracture is a manifestation of reduced bone strength and osteoporosis. This study aims to assess the frequency of spine fractures in HIV-positive men and women aged over 18 years. We performed a systematic review of randomized controlled trials, cohort studies, cross-sectional studies, and case-control studies. Studies that evaluated morphometric and/or clinical vertebral fracture were included. In total 488 studies were found, of which 53 had their full texts evaluated. A total of 85,411 HIV positive individuals were identified in 26 studies. The meta-analysis of the prevalence of vertebral fractures included 12 studies with 10,593 subjects. The prevalence was 11.1% [95% confidence interval (95% CI) 4.5%, 25.0%, I² 98.2% p < 0.00001]. When we evaluated independently studies of clinical vertebral fracture and morphometric vertebral fracture, the prevalence was 3.9% (95% CI 0.9, 15.8, I² 96.4% p < 0.00001) and 20.2% (95% CI 15.7%, 25.6%, I² 69.9% p = 0.003) respectively. HIV-infected individuals had an odds ratio of vertebral fractures of 2.3 (95% CI 1.37, 3.85, I² 98.2% p < 0.00001) when compared with HIV-uninfected patients (n = 9 studies). In conclusion, HIV-positive subjects had a higher risk of vertebral fractures when compared with HIV-negative subjects.

Bone density, microarchitecture, and tissue quality after 1 year of treatment with tenofovir disoproxil fumarate

OBJECIVE

Bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) is used to assess bone health in HIV patients. DXA measures the amount of mineral, but not other key aspects of bone strength such as bone microarchitecture or bone quality. Trabecular bone score (TBS) and in-vivo microindentation directly measure trabecular microarchitecture and bone tissue quality, respectively. The aim of this study is to measure bone strength properties using these techniques.

RESULTS

Forty naive HIV patients who were going to start antiretroviral therapy (ART), a single pill treatment with elvitegravir/cobicistat, tenofovir disoproxil fumarate (TDF), emtricitavine (FTC) were included. A significant reduction in BMD at spine (-3.25%, P < 0.001) and in femoral neck (-3.82%, P = 0.016) between baseline and 48 weeks of treatment were found. Bone microarchitecture score at the spine, as measured by TBS, also significantly decreased from 1.357 (0.09) to 1.322 (0.09) (-2.5%, P = 0.011) between baseline to 48 weeks of treatment. Microindentation (BMSi) values were significantly higher than at baseline [89.04 (4.2) versus 86.07 (6.1); 3.49%, P < 0.001] after 48 weeks of TDF-based ART treatment, indicating improved bone material properties CONCLUSION:: A significant decrease in BMD and TBS were observed after 1 year of TDF therapy. However, tissue quality significantly improved after 1 year of treatment, suggesting a recovery of bone material properties following the control of the infection despite the significant reduction of BMD. These techniques provide additional and necessary information to DXA about bone health in treated HIV patients, and because of its convenience and feasibility they could be routinely apply to assess bone in clinical practice.

The role of carboxy-terminal cross-linking telopeptide of type I collagen, dual x-ray absorptiometry bone strain and Romberg test in a new osteoporotic fracture risk evaluation: A proposal from an observational study

The consolidated way of diagnosing and treating osteoporosis in order to prevent fragility fractures has recently been questioned by some papers, which complained of overdiagnosis and consequent overtreatment of this pathology with underestimating other causes of the fragility fractures, like falls. A new clinical approach is proposed for identifying the subgroup of patients prone to fragility fractures. This retrospective observational study was conducted from January to June 2015 at the Nuclear Medicine-Bone Metabolic Unit of the of the Fondazione IRCCS Ca' Granda, Milan, Italy. An Italian population of 125 consecutive postmenopausal women was investigated for bone quantity and bone quality. Patients with neurological diseases regarding balance and vestibular dysfunction, sarcopenia, past or current history of diseases and use of drugs known to affect bone metabolism were excluded. Dual X-ray absorptiometry was used to assess bone quantity (bone mineral density) and bone quality (trabecular bone score and bone strain). Biochemical markers of bone turnover (type I collagen carboxy-terminal telopeptide, alkaline phosphatase, vitamin D) have been measured. Morphometric fractures have been searched by spine radiography. Balance was evaluated by the Romberg test. The data were evaluated with the neural network analysis using the Auto Contractive Map algorithm. The resulting semantic map shows the Minimal Spanning Tree and the Maximally Regular Graph of the interrelations between bone status parameters, balance conditions and fractures of the studied population. A low fracture risk seems to be related to a low carboxy-terminal cross-linking telopeptide of type I collagen level, whereas a positive Romberg test, together with compromised bone trabecular microarchitecture DXA parameters, appears to be strictly connected with fragility fractures. A simple assessment of the risk of fragility fracture is proposed in order to identify those frail patients at risk for osteoporotic fractures, who may have the best benefit from a pharmacological and physiotherapeutic approach.