Overall benefit of antiretroviral treatment on the risk of fracture in HIV: nested case-control analysis in a health-insured population

HIV and fracture: Risk, assessment and intervention

OBJECTIVES

With management of comorbidity in people living with HIV (PLWH) a key component of clinical care, early loss of bone integrity and clinical fracture are recognized as important issues. This review aims to describe the epidemiology of fracture in PLWH, as well as summarizing the relative balance of factors that contribute to fracture. We also aim to describe fracture risk assessment and interventional strategies to modify the risk of fracture in this population.

RESULTS

Data from recent meta-analyses show that PLWH have significantly more fractures than the general population, with men and injecting drug users at higher risk. Modifiable factors that contribute to fracture risk in this cohort include body mass index (BMI), drug use, concurrent medications, frailty, and hepatitis C virus infection. Relating to antiretroviral therapy, current or ever tenofovir exposure has been identified as predictive of fracture but not cumulative use, and a potentially modest protective effect of efavirenz has been observed. Fracture Risk Assessment Tool scores underestimate fracture risk in PLWH with improved accuracy when HIV is considered a cause of secondary osteoporosis and bone mineral density (BMD) included.

CONCLUSION

Early consideration of risk, prompting evaluation of modifiable risk factors, frailty and falls risk with bone density imaging and prompt intervention may avert fracture in PLWH. Guidance on screening and lifestyle modification is available in international guidelines. Bisphosphonates are safe and effective in PLWH, with limited data for other agents.

Primary Care of the Person Living with HIV

Life-changing progress has been made over the past 30 years in the treatment of HIV infection. HIV has transformed from an illness that resulted in one complication after another and nearly always resulted in death to a chronic illness that for most patients is more easily managed than diabetes or heart disease. Antiretroviral therapy (ART) is now simple and well-tolerated. The most important priority of HIV treatment is ensuring that people living with HIV stay on continuous, effective ART. ART, although not curative, suppresses the virus and allows the immune system to recover. Even when the CD4 count remains low, suppressive ART helps prevent opportunistic infections and other HIV related complications. (1) Suppressive ART is important not only to the individual living with HIV health but is an important public health goal since people living with HIV will not transmit HIV to their sexual partners if their viral load is undetectable. (2) A respectful, culturally appropriate patient–provider relationship is one of the most important factors in keeping people living with HIV engaged in care. (3) Persons living with HIV deserve both excellent HIV and primary care. Some communities have providers that are experts in both, but often people living with HIV receive the best care by collaboration between their primary care provider and an HIV expert. This article is written to help primary care givers who are not HIV experts provide appropriate primary care to their patients who are living with HIV and emphasizes issues that deserve additional attention in people living with HIV compared to the general population

Fractures Related to Tenofovir: A Case/Noncase Study in the European Pharmacovigilance Database

BACKGROUND

There is no clear consensus on the relationship between tenofovir (TDF) and fracture risk because the studies published so far present contradictory findings.

STUDY QUESTION

Our objective was to detect, from the European pharmacovigilance database (EudraVigilance), a signal of fracture risk during TDF exposure in patients infected with HIV.

METHODS

Herein, we analyze all the cases of fractures suspected to be related to TDF recorded in EudraVigilance between 2001 and November 10, 2016. A case/noncase method was used to assess the association between fractures and TDF, calculating proportional reporting ratios (PRRs) and their 95% confidence intervals (CIs) as a measure of disproportionality. According to the Medical Dictionary for Regulatory Activities (MedDRA) terminology, osteoporotic fractures are included in High Level Group Term (HLGT) "Fractures" and traumatic fractures in HLGT "Bone and joint injuries," so, we selected cases included in both HLGTs. The noncases used as controls were all the remaining adverse drug reaction reports recorded in EudraVigilance during the same period.

RESULTS

There were 68,113 cases of fractures in the 4,776,472 reports recorded in EudraVigilance during the study period. TDF was involved in 181 cases. The median latency period until the appearance of fracture was 995 days. TDF was present as the only suspect drug in 140 cases. The PRR of TDF and fractures was 1.11 (95% CI, 0.96-1.28). Nevertheless, disproportionality was observed for some types of fractures: osteoporotic fractures (PRR 17.24; 95% CI, 9.90-30.01), bone fissure (PRR 16.60; 95% CI, 6.11-45.10), and pathological fracture (PRR 4.40; 95% CI, 2.77-7.00).

CONCLUSIONS

Our findings do not show a disproportionality for fractures in patients treated with TDF, although disproportionality was found for some types of fractures, mainly osteoporotic fractures.

Impact of Antiretroviral Drugs on Fracture Risk in HIV-Infected Individuals: A Case-Control Study Nested Within the French Hospital Database on HIV (FHDH-ANRS CO4)

BACKGROUND

HIV-infected patients have lower bone mineral density and a higher incidence of fractures than the general population of the same age and sex. To assess the impact of antiretroviral (ARV) drugs exposure on the risk of osteoporotic fractures, we conducted a nested case-control study.

METHODS

Cases were individuals enrolled while ARV-naive, with a first prospectively recorded fracture between 2000 and 2010. Controls were randomly selected after matching for sex, age (±3 years), period of HIV diagnosis (<1997/≥1997), and clinical center. The risk of fracture was analyzed with conditional logistic regression models, using different ways to model ARV exposure. All exposure variables and potential confounders were included in multivariable models.

RESULTS

Among 861 reviewed cases, 261 fractures were osteoporotic and 254 of cases were matched to at least one control (376 controls). The median year of fracture diagnosis was 2007 (interquartile range 2004-2009): 49% of patients had been exposed to tenofovir disoproxil fumarate (TDF) and 82% to protease inhibitors (PIs). After taking into account the transmission group, AIDS status, geographic origin, body mass index, current smoking status, alcohol consumption, exposure to systemic glucocorticoids, and the period of enrollment, there was no association between the risk of fracture and exposure to TDF [odds ratio for cumulative exposure: 1.04 (0.86-1.27), similar results for ever-exposed subjects], to nucleoside reverse transcriptase inhibitors, or to PIs [odds ratio for cumulative PI exposure: 1.02 (0.92-1.12)].

CONCLUSIONS

We found no evidence of an excess risk of fracture after exposure to TDF or PIs. This has important implications for the debate concerning tenofovir alafenamide versus generic TDF.

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.

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.

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.

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.

Factors associated with fractures in HIV-infected persons: which factors matter?

This study aims to determine what factors are associated with increased risk of fracture among patients with HIV, in particular whether an important medication used to treat HIV, tenofovir, is associated with fracture. Our study found that while co-infection with hepatitis C and markers of HIV severity were associated with fracture, tenofovir was not.

INTRODUCTION

Growing evidence suggests that tenofovir disoproxil fumarate decreases bone density among patients with HIV, but there are conflicting reports as to whether this decrease in bone density translates to higher fracture risk. We aimed to determine what factors were associated with an increased risk of fracture for patients with HIV, in particular whether tenofovir is associated with elevated fracture risk.

METHODS

We conducted a retrospective cohort study at two tertiary care hospitals in Boston, MA, between 2001 and 2012 to determine whether tenofovir use is associated with elevated all-site fracture risk, as compared to other antiretroviral medications. We also examined other potential factors associated with fracture among patients with HIV.

RESULTS

We identified 1981 HIV-infected patients who had at some point used tenofovir and 682 patients who had not. The mean age was 43 years, and 72 % were male. The hepatitis C co-infection rate was 28 %, about 40 % had nadir CD4 count <200, and about 40 % had a history of an AIDS-defining illness. We did not find an association between risk of fracture and tenofovir disoproxil fumarate (TDF) (adjusted RR (aRR) 0.8, 95 % CI 0.6-1.1). However, co-infection with hepatitis C did increase risk of fracture (aRR 1.6, 95 % CI 1.1-2.3), as did nadir CD4 count <200 (aRR 3.1, 95 % CI 1.9-5.0) and history of AIDS-defining illness (aRR 1.6, 95 % CI 1.1-2.2).

CONCLUSION

There was no association found between fracture and tenofovir use, but there were associations between co-infection with hepatitis C and markers of advanced HIV disease and fracture.

Tenofovir and bone health

PURPOSE OF REVIEW

With continued improvements to the antiviral efficacy and tolerability of antiretroviral therapy, long-term safety of antiretroviral therapy has become paramount. Low bone mineral density and fragility fractures are more common in HIV-infected individuals than in the general population. The aims of this review are to describe potential mechanisms underlying the adverse effects of tenofovir on bone, clinical studies of tenofovir disoproxil fumarate (TDF) and bone, and more recent bone data on tenofovir alafenamide.

RECENT FINDING

Several studies have demonstrated an approximately 1-3% greater bone mineral density loss with TDF compared with other agents. Recent studies with tenofovir alafenamide have shown improved bone (and renal) safety with similar virologic efficacy when compared to TDF.

SUMMARY

Given these findings, TDF-containing regimens may be gradually replaced with non-TDF containing regimens for the treatment of HIV infection, especially in those at higher risk for fragility fracture.

Do people with HIV infection have a higher risk of fracture compared with those without HIV infection?

PURPOSE OF REVIEW

This review details recent findings that inform the prevalence and incidence of fractures in people living with HIV (PLWH) and examines the effects of HIV infection and antiretroviral therapy (ART), as well as demographics and traditional risk factors on fractures. As antiretroviral guidelines have recently changed to recommend the introduction of ART at diagnosis of HIV infection, the long-term effects of ART on bone health and fracture risk need to be better understood.

RECENT FINDINGS

It is apparent that both the effects of HIV infection alone and initiation of ART are associated with significant bone loss in individuals with HIV infection, resulting in osteopenia and osteoporosis. The clinical consequence of low bone mineral density is a greater risk of fragility fractures that are more common in older HIV patients, and those on ART. Frailty occurs at a prevalence of about 10% (about twice that of the general population), and the increased propensity of falls results in greater fracture prevalence, morbidity and mortality.

SUMMARY

This review examines data from recent cohort studies and clinical trials to inform a better understanding of the complex relationship between the effects of HIV infection, ART and demographics on fractures in PLWH.

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.

Key toxicity issues with the WHO-recommended first-line antiretroviral therapy regimen

INTRODUCTION

WHO recommends tenofovir, efavirenz, and lamivudine or emtricitabine for first-line antiretroviral therapy (ART) in adults, which replaced more toxic regimens using stavudine, zidovudine or nevirapine. Areas covered: We searched Pubmed to identify observational studies and randomized controlled trials reporting toxicity of these antiretrovirals published between 2011 and 2016, and hand-searched abstracts presented at major HIV conferences in 2015 and 2016, focusing on data from sub-Saharan Africa. Tenofovir's nephrotoxicity manifests as mild renal tubular dysfunction (common and of uncertain clinical significance), acute kidney injury (rare), and chronic declining glomerular filtration rate (common). African studies, which include high proportions of patients with renal dysfunction from opportunistic diseases, report population improvement in renal function after starting tenofovir-based ART. Tenofovir modestly decreases bone mineral density, and there is emerging data that this increases fracture risk. Efavirenz commonly causes early self-limiting neuropsychiatric toxicity and hypersensitivity rashes. Recent studies have highlighted its long-term neuropsychiatric effects, notably suicidality and neurocognitive impairment, and metabolic toxicities (dyslipidemia, dysglycemia, and lipoatrophy). We point out the challenges clinicians face in the recognition and attribution of adverse drug reactions. Expert commentary: Tenofovir and efavirenz are generally well tolerated, but both are associated with potentially serious toxicities. Pharmacovigilance systems in resource-limited settings with high HIV burden should be strengthened.

Increased Fracture Incidence in Middle-Aged HIV-Infected and HIV-Uninfected Women: Updated Results From the Women's Interagency HIV Study

BACKGROUND

We previously reported that fracture incidence rates did not differ by HIV status among predominantly premenopausal Women's Interagency HIV Study participants. We now conduct a follow-up study with 5 additional observation years to further characterize fracture risk associated with HIV infection in women as they age.

METHODS

We measured time to first new fracture at any site in 2375 (1713 HIV-infected and 662 HIV-uninfected) Women's Interagency HIV Study participants, with median 10-year follow-up. Fractures were self-reported semiannually. Proportional hazards models assessed predictors of incident fracture.

RESULTS

At index visit, HIV-infected women were older [median age of 40 years (IQR: 34-46) vs. 35 (27-43), P < 0.0001] and more likely to be postmenopausal, hepatitis C virus infected, and weigh less than HIV-uninfected women. Among HIV-infected women, mean CD4 count was 480 cells per microliter and 63% were taking highly active antiretroviral therapy. Unadjusted incidence rates of any fracture were higher in HIV-infected than in HIV-uninfected women [2.19/100 person-years (py) vs. 1.54/100 py, P = 0.002]. In multivariate models, HIV status, older age, white (vs. black) race, prior fracture, history of cocaine use, and history of injection drug use were significant predictors of incident fracture. Among HIV-infected women, age, white race, prior fracture, smoking, and prior AIDS were predictors of new fracture.

CONCLUSIONS

Middle-aged HIV-infected women had a higher adjusted fracture rate than HIV-uninfected women. Cocaine use and injection drug use were also associated with a greater risk of incident fracture. Further research is needed to understand whether the risk of fracture associated with cocaine use relates to increased rate of falls or direct effects on bone metabolism.

Assessment of radiological vertebral fractures in HIV-infected patients: clinical implications and predictive factors

OBJECTIVES

The aim of this study was to evaluate the clinical impact of including lateral spine X-ray in the screening of bone diseases in HIV-positive patients.

METHODS

A total of 194 HIV-positive patients underwent dual-energy X-ray absorptiometry (DEXA), lateral spine X-ray and bone biochemical analysis. Vertebral fractures were identified using a morphometric analysis of X-rays and classified using the semiquantitative scoring system of Genant et al. For each patient, a spine deformity index (SDI) score was calculated by summing the grades of vertebral deformities. Reductions in vertebral body height of > 25% were considered vertebral fractures, and those < 25% were considered vertebral deformities. Risk factors associated with vertebral fractures were evaluated by univariate and multivariate analysis.

RESULTS

Vertebral fractures were detected in 24 patients (12.4%) and vertebral deformities in 17 patients (8.7%); 153 patients (78.9%) did not show any vertebral deformity. Among patients with fractures, only two with SDI > 10 reported lumbar pain; the remaining were asymptomatic. Patients over 50 years old showed a higher prevalence of vertebral fracture [24.4% versus 11.8% in patients 41-50 years old (P = 0.05) and 1.9% in patients ≤ 40 years old (P = 0.04)]. No significant increase in the prevalence according to bone mineral density (BMD) reduction was observed, and 70% of fractures were diagnosed in nonosteoporotic patients. Older age [adjusted odds ratio 1.09; 95% confidence interval (CI) 1.03-1.13; P = 0.001] and steroid use (adjusted odds ratio 3.64; 95% CI 1.29-10.3; P = 0.01) were independently associated with vertebral fracture; no association was found with HIV- or highly active antiretroviral therapy (HAART)-related variables.

CONCLUSIONS

A prevalence of vertebral fractures of 12.4% was observed in our HIV-positive cohort. Given that two-thirds of fractures occurred in nonosteoporotic patients, spine X-ray may be considered in patients at increased risk, irrespective of BMD; that is, in elderly patients and/or patients using steroids.

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.

Primary care of women aging with HIV

Women are living longer with HIV infection, but their life expectancy remains shorter than for women in the general population. How best to manage the multiple comorbidities and polypharmacy that are common in individuals wtih HIV has not been studied. This article explores areas where the primary care of women with HIV may differ from that of aging women in the general population. We also discuss aspects of care that may not commonly be considered in those under the age of 65, specifically multimorbidity and polypharmacy. Incorporating a gerontologic approach in the care of these women may optimize outcomes until research provides more definitive answers for how best to collaborate with women with HIV in order to provide them with optimal care.

Changes in bone mineral density after 96 weeks of treatment with atazanavir/ritonavir or lopinavir/ritonavir plus tenofovir DF/emtricitabine in treatment-naive patients with HIV-1 infection: the CASTLE body composition substudy

: Antiretroviral therapy initiation is associated with declines in bone mineral density (BMD), which seem greatest with tenofovir disoproxil fumarate (DF)-containing regimens. Data comparing protease inhibitors are limited. This CASTLE substudy compared paired baseline with week 96 BMD in patients initiating tenofovir DF/emtricitabine plus atazanavir/ritonavir (n = 106) vs lopinavir/ritonavir (n = 70). In both groups, week 96 BMD declined significantly in arm, leg, trunk, and total body regions. Atazanavir/ritonavir was associated with smaller 96-week trunk and total body BMD declines compared with lopinavir/ritonavir [multivariate-adjusted least squares mean difference +2.00% (95% confidence interval: 0.52 to 3.45; P = 0.008) and +1.24% (95% confidence interval: 0.13 to 2.35; P = 0.029), respectively]. In addition, low baseline CD4 cell count (<50 cells per microliter) and increasing age were associated with larger declines in BMD.

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.

Proton pump inhibitors and risk of bone fractures

OPINION STATEMENT

There are 34 studies in almost 2 million participants that have reported on the association between proton pump inhibitor (PPI) therapy and risk of fracture. There is substantial variation between the results of each study but systematic reviews of the data suggest overall there is an association between PPI therapy and risk of fracture. The magnitude of the association is modest and is most likely due to confounding factors as patients prescribed PPI therapy tend to be more frail with more risk factors for fractures than those not given these drugs. There is no clear dose-response relationship and there is no association between PPI therapy and risk of fracture in those at highest risk. Finally, there is no clear mechanism through which PPI therapy increases the risk of fracture, as recent randomized trials show no impact of PPI therapy on calcium absorption and there is no association between PPI therapy and risk of osteoporosis. We therefore feel there is insufficient evidence to change PPI prescribing habits based on risk of fracture. Similarly, we do not recommend bone mineral density investigations for patients taking PPI therapy other than would be normally indicated. There is no evidence to support prescription of calcium and/or vitamin D in patients simply because they are taking PPI therapy. As with all medications, we only recommend prescribing PPI therapy when there is a clear indication that benefit will outweigh risk and at the lowest effective dose. Patients should be regularly assessed as to whether acid suppression is still required.

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.

Comparison of peripheral forearm DXA and clinical risk factor screening using FRAX® to assess the risk of HIV-associated low bone mass: a cross-sectional study

There is growing awareness that HIV infection is associated with low bone mass and fracture. DXA is a relatively scarce resource. Therefore, we evaluated two tools: peripheral DXA (pDXA) at the forearm and Fracture Risk Assessment Tool (FRAX®) to see which performed best at identifying men who should undergo DXA. In this setting, neither pDXA nor FRAX® showed good sensitivity and specificity for DXA.

PURPOSE

Infection with human immunodeficiency virus (HIV) is associated with an increased risk of low bone mineral density (BMD) and fractures. European guidance advocates screening using the FRAX® tool at diagnosis, on initiation of antiretroviral therapy and biannually thereafter in order to decide the need for DXA scanning. This cross-sectional study evaluates the performance of FRAX® and compares its sensitivity and specificity with that of another screening tool, peripheral forearm DXA (pDXA).

METHODS

HIV-infected men with varying exposure to antiretroviral therapies were recruited. FRAX® scores were calculated for all participants and everybody underwent pDXA scanning. Femoral neck and lumbar spine BMD was acquired on a Hologic QDR machine by an assessor blinded to the results of the FRAX® and pDXA.

RESULTS

One hundred and sixty-eight men (median age 45 years) were recruited with a median duration since HIV diagnosis of 74 months. In total, 21 % of subjects had either osteoporosis (aged ≥50 years) or BMD lower than expected for age (aged <50 years), according to axial DXA. Using a pDXA screening threshold of T ≤ -0.9, sensitivity was high (91 %) in defining those with the worst BMD on axial DXA but with poorer specificity (33 %). Alternately, using a threshold of T ≤ -2.7 reduced sensitivity (34 %) with an increase in specificity (91 %). FRAX® with HIV included as a secondary risk factor had poor sensitivity (31 %) and specificity (74 %) for detecting those with the poorest BMD on axial DXA.

CONCLUSION

In this setting, neither pDXA scanning nor FRAX® was sensitive and specific for low bone mass on DXA and neither was performance much improved by using both screening tools. Prospective studies with fracture as an outcome are required in HIV.

Chronic viral hepatitis is associated with low bone mineral density in HIV-infected patients, ANRS CO 3 Aquitaine Cohort

BACKGROUND

High prevalence rates of low bone mineral density (BMD) have been reported in people living with HIV infection. We aimed to investigate the association of chronic viral hepatitis with low BMD in HIV-infected patients.

METHODS

A hospital-based cohort of HIV-infected patients was screened for hepatitis B and C coinfection. BMD was measured by dual energy x-ray absorptiometry. T-score was used to define bone status according to the World Health Organization's classification; moreover, each observed BMD value was compared with reference to an average person of the same age and gender as a Z-score <-2.0 allow the diagnosis of patients having less bone mass and/or losing bone material more rapidly than expected. A polytomial logistic regression was performed by gender to investigate the association between chronic viral hepatitis and low BMD (osteopenia and osteoporosis) in HIV-infected patients.

RESULTS

A total of 626 patients (166 females of whom 52 postmenopausal) were recruited: 357 HIV monoinfected, and 269 HIV-coinfected with chronic viral hepatitis, among whom 61 with a diagnosis of cirrhosis. Osteopenia was present in 320 patients (51.1%) and osteoporosis in 187 (29.9%). After adjustment, osteoporosis was associated with older age and low body mass index in both genders. The association between chronic viral hepatitis B or C and osteoporosis was found in women only (odds ratio: 19.0; P value: 0.047).

CONCLUSIONS

We found a high prevalence of low BMD overall, but chronic viral hepatitis was independently associated with osteoporosis only in female participants. Our data confirm the need of BMD evaluations for patients living with HIV.

Prevalence of and risk factors for osteoporosis and fracture among a male HIV-infected population in the UK

Rates of osteoporosis and fracture may be increased in HIV but there are few UK data. Our aim was to examine the prevalence of and risk factors for osteoporosis and fractures among a homogeneous cohort of well-characterized HIV-infected men. In total, 168 men were recruited, median age 45 years, 37 combination antiretroviral therapy (cART) naïve, 46 with <3 years cART exposure and 85 cART-exposed longer term (median >10 years). All participants provided information on bone health and underwent DEXA scanning. Osteopenia was found in 58% of subjects and osteoporosis in 12%; 14% reported fractures since HIV diagnosis. Number of fractures since HIV diagnosis was significantly increased among those with osteoporosis (OR 3.5, 95% CI 1.2-10.4, p = 0.018). Duration of infection greater than 13 years was significantly associated with osteoporosis. Duration of cART was associated in univariate but not multivariate analyses. Strategies to prevent osteoporosis and fractures in HIV will require attention to viral and lifestyle factors and not just cART.

Long-term HIV infection and antiretroviral therapy are associated with bone microstructure alterations in premenopausal women

We evaluated the influence of long-term HIV infection and its treatment on distal tibia and radius microstructure. Premenopausal eumenorrheic HIV-positive women displayed trabecular and cortical microstructure alterations, which could contribute to increased bone fragility in those patients.

INTRODUCTION

Bone fragility is an emerging issue in HIV-infected patients. Dual-energy X-ray absorptiometry (DXA) quantified areal bone mineral density (BMD) predicts fracture risk, but a significant proportion of fracture risk results from microstructural alterations.

METHODS

We studied the influence of long-term HIV infection on bone microstructure as evaluated by high-resolution peripheral quantitative computed tomography (HR-pQCT) in 22 HIV-positive (+ve) premenopausal eumenorrheic women and 44 age- and body mass index (BMI)-matched HIV-negative (-ve) controls. All subjects completed questionnaires regarding calcium/protein intakes and physical activity, and underwent DXA and HR-pQCT examinations for BMD and peripheral skeleton microstructure, respectively. A risk factor analysis of tibia trabecular density using linear mixed models was conducted.

RESULTS

In HIV+ve women on successful antiretroviral therapy (undetectable HIV-RNA, median CD4 cell count, 626), infection duration was 16.5 ± 3.5 (mean ± SD) years; median BMI was 22 (IQR, 21-26) kg/m². More HIV+ve women were smokers (82 versus 50 %, p = 0.013). Compared to controls, HIV+ve women had lower lumbar spine (spine T-score -0.70 vs -0.03, p = 0.014), but similar proximal femur BMD. At distal tibia, HIV+ve women had a 14.1 % lower trabecular density and a 13.2 % reduction in trabecular number compared to HIV-ve women (p = 0.013 and 0.029, respectively). HR-pQCT differences in distal radius were significant for cortical density (-3.0 %; p = 0.029).

CONCLUSIONS

Compared with HIV-ve subjects, premenopausal HIV+ve treated women had trabecular and cortical bone alterations. Adjusted analysis revealed that HIV status was the only determinant of between group tibia trabecular density differences. The latter could contribute to increased bone fragility in HIV+ve patients.

Bone health and human immunodeficiency virus infection

Low bone mineral density is common among persons with human immunodeficiency virus (HIV) infection, and studies reporting increased fracture rates in this patient population are emerging. The causes of low bone mineral density, osteoporosis, and fractures in persons with HIV are likely multifactorial, involving traditional risk factors, HIV infection, and exposure to antiretroviral treatment. Specific antiretrovirals such as tenofovir may cause a greater loss of bone mineral density compared with other agents and have recently been linked to an increased risk for fracture. As a result, recent treatment guidelines suggest that clinicians consider avoiding tenofovir as initial therapy in postmenopausal women. Evaluating bone mineral density and vitamin D status in persons with HIV may be important steps in identifying those requiring pharmacotherapy; however, the appropriate timing for bone mineral density and vitamin D screening is uncertain, as is the appropriate method of replacing vitamin D in HIV-positive patients who are deficient. Further study is necessary to definitively determine the approach to evaluating bone health and managing low bone mineral density and vitamin D deficiency in patients with HIV infection.

HIV and its effects on bone: a primer for rheumatologists

PURPOSE OF REVIEW

As patients with HIV are living longer because of effective treatments, rates of comorbid chronic diseases such as bone complications are increasing. There is a growing body of literature showing increased rates of osteopenia and osteporosis in the HIV population. Less is known about the risk of fracture, as well as other bone complications, such as avascular necrosis (AVN).

RECENT FINDINGS

Increased rates of osteopenia and osteoporosis are seen in the HIV population, likely secondary to an interaction of traditional osteoporotic and HIV-specific risk factors, and possibly the effect of antiretroviral therapy (ART). There are conflicting recent data as to whether the decrease in bone mineral density seen in the HIV population, specifically with particular ART regimens, translates into an increased risk of fracture. Conflicting evidence emerges from recent studies exploring whether supplementation of vitamin D and calcium can prevent the bone loss seen with specific ART regimens.

SUMMARY

Bone disease is common in the HIV population, and will likely be a medical problem increasingly seen by rheumatologists. The role of ART regimens on bone complications such as fracture and AVN is unclear, and further research in this area as well as possible prevention strategies are needed.

Fractures after antiretroviral initiation

BACKGROUND

Bone mineral density declines by 2-6% within 1-2 years after initiation of antiretroviral therapy (ART); however, it is uncertain whether this results in an immediate or cumulative increase in fracture rates.

METHODS

We evaluated the incidence and predictors of fracture in 4640 HIV-positive participants from 26 randomized ART studies followed in the AIDS Clinical Trials Group (ACTG) Longitudinal-Linked Randomized Trial study for a median of 5 years. Fragility and nonfragility fractures were recorded prospectively at semiannual visits. Incidence was calculated as fractures/total person-years. Cox proportional hazards models evaluated effects of traditional fracture risks, HIV disease characteristics, and ART exposure on fracture incidence.

RESULTS

Median (interquartile range) age was 39 (33, 45) years; 83% were men, 48% white, and median nadir CD4 cell count was 187 (65, 308) cells/μl. Overall, 116 fractures were reported in 106 participants with median time-to-first fracture of 2.3 years. Fracture incidence was 0.40 of 100 person-years among all participants and 0.38 of 100 person-years among 3398 participants who were ART naive at enrollment into ACTG parent studies. Among ART-naive participants, fracture rates were higher within the first 2 years after ART initiation (0.53/100 person-years) than subsequent years (0.30/100 person-years). In a multivariate analysis of ART-naive participants, increased hazard of fracture was associated with current smoking and glucocorticoid use but not with exposure to specific antiretrovirals.

CONCLUSION

Fracture rates were higher within the first 2 years after ART initiation, relative to subsequent years. However, continuation of ART was not associated with increasing fracture rates in these relatively young HIV-positive individuals.