Ten-year incidence and risk factors of bone fractures in a cohort of treated HIV1-infected adults

In HIV/hepatitis C virus co-infected patients, higher 25-hydroxyvitamin D concentrations were not related to hepatitis C virus treatment responses but were associated with ritonavir use

BACKGROUND

Among patients with hepatitis C virus (HCV) monoinfection, 25-hydroxyvitamin D [25(OH)D] concentrations are positively associated with a response to peg-interferon/ribavirin. Data on the relation between 25(OH)D concentrations and HCV treatment response in HIV-infected patients are limited.

OBJECTIVE

The objective was to determine whether baseline 25(OH)D concentrations predict virologic response in HIV/HCV co-infected patients and to examine variables associated with 25(OH)D concentrations ≥30 ng/mL.

DESIGN

Data and samples from 144 HCV genotype 1, treatment-naive patients from a completed HCV treatment trial were examined in this retrospective study. Early virologic response (EVR) was defined as ≥2 log10 reduction in HCV RNA and/or HCV RNA <600 IU/mL at week 12 of peg-interferon/ribavirin treatment. Baseline 25(OH)D was measured by liquid chromatography/tandem mass spectrometry.

RESULTS

Compared with the non-EVR control group (n = 68), the EVR group (n = 76) was younger, had fewer cirrhotic subjects, had a higher proportion with the IL28B CC genotype, had a higher albumin concentration, and had a lower HCV viral load at baseline (P ≤ 0.05). The difference in baseline 25(OH)D concentrations between EVR and non-EVR patients was not statistically significant (median: 25 ng/mL compared with 20 ng/mL; P = 0.23). Similar results were found for sustained virologic response (SVR). In multivariable analysis, white and Hispanic race-ethnicity (OR: 6.26; 95% CI: 2.47, 15.88; P = 0.0001) and ritonavir use (OR: 2.68; 95% CI: 1.08, 6.65; P = 0.033) were associated with higher 25(OH)D concentrations (≥30 ng/mL).

CONCLUSION

Baseline 25(OH)D concentrations did not predict EVR or SVR. Because ritonavir impairs the conversion of 25(OH)D to the active metabolite, utilization of 25(OH)D may have been impaired in subjects taking ritonavir. This trial was registered at www.clinicaltrials.gov as NCT00078403.

The next therapeutic challenge in HIV: polypharmacy

With the adoption of combination antiretroviral therapy (ART), most HIV-infected individuals in care are on five or more medications and at risk of harm from polypharmacy, a risk that likely increases with number of medications, age, and physiologic frailty. Established harms of polypharmacy include decreased medication adherence and increased serious adverse drug events, including organ system injury, hospitalization, geriatric syndromes (falls, fractures, and cognitive decline) and mortality. The literature on polypharmacy among those with HIV infection is limited, and the literature on polypharmacy among non-HIV patients requires adaptation to the special issues facing those on chronic ART. First, those aging with HIV infection often initiate ART in their 3rd or 4th decade of life and are expected to remain on ART for the rest of their lives. Second, those with HIV may be at higher risk for age-associated comorbid disease, further increasing their risk of polypharmacy. Third, those with HIV may have an enhanced susceptibility to harm from polypharmacy due to decreased organ system reserve, chronic inflammation, and ongoing immune dysfunction. Finally, because ART is life-extending, nonadherence to ART is particularly concerning. After reviewing the relevant literature, we propose an adapted framework with which to address polypharmacy among those on lifelong ART and suggest areas for future work.

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

OBJECTIVE(S)

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

DESIGN

A systematic review and meta-analysis.

METHODS

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

RESULTS

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

CONCLUSION

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

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.

HIV infection is strongly associated with hip fracture risk, independently of age, gender, and comorbidities: a population-based cohort study

HIV infection and antiretroviral therapies have detrimental effects on bone metabolism, but data on their impact on fracture risk are controversial. We conducted a population-based cohort study to explore the association between clinical diagnosis of HIV infection and hip and major osteoporotic fracture risk. Data were obtained from the SIDIAP(Q) database, which contains clinical information for >2 million patients in Catalonia, Spain (30% of the population). We screened the database to identify participants with a clinical diagnosis of HIV infection, and ascertained incident hip and osteoporotic major fractures in the population aged 40 years or older in 2007 to 2009. In addition, data on incident fractures involving hospital admission were obtained from the Hospital Admissions database. Cox regression models were used to estimate hazard ratios (HRs) for the HIV-infected versus uninfected participants. Models were adjusted for age, sex, body mass index, smoking status, alcohol drinking, oral glucocorticoid use, and comorbid conditions (Charlson index). Among 1,118,156 eligible participants, we identified 2489 (0.22%) subjects with a diagnosis of HIV/AIDS. Age- and sex-adjusted HR for HIV/AIDS were 6.2 (95% confidence interval [CI] 3.5-10.9; p < 0.001) and 2.7 (2.01-3.5; p < 0.001) for hip and major fractures, respectively; this remained significant after adjustment for all mentioned potential confounders: HR 4.7 (2.4-9.5; p < 0.001) and 1.8 (1.2-2.5; p = 0.002). After stratifying by age, the association between HIV infection and major fractures was attenuated for those aged <59 years (adjusted HR 1.35 [0.88-2.07], p = 0.17) but appeared stronger in older patients (adjusted HR 2.11 [1.05-4.22], p = 0.035). We report a strong association between HIV infection and hip fracture incidence, with an almost fivefold increased risk in the HIV infected, independent of sex, age, smoking, alcohol drinking, and comorbidities. Similarly, we demonstrate a 75% higher risk of all clinical fractures and a 60% increase in risk of non-hip clinical fractures among patients with a diagnosis of HIV infection.

Impact of hepatitis C virus infection on bone mineral density in renal transplant recipients

BACKGROUND

The average prevalence of hepatitis C virus (HCV) infection in renal transplant recipients is 10%. Studies of these patients with HCV infection usually focuses on long-term graft survival and patient survival. Studies of the correlation between HCV infection and bone mineral density (BMD) in renal transplant patients are limited. The aim of this study was to investigate whether HCV infection is a risk factor for BMD change during a short follow-up period.

METHODS

Seventy-six renal transplant recipients underwent 2 separate dual-energy X-ray absorptiometry (DXA) scans during a mean period of 14 months. Fifteen patients were HCV infection. First bone mineral density (BMD) at the lumbar spine, hip, and femoral neck was determined using dual-energy X-ray absorptiometry (DXA) between September 2008 and March 2009. After that, 34 patients took alendronate sodium 70 mg per week. Subgroups risk factors analysis was also performed into with or without alendronate. Immunosuppressive agents, bisphosphonates, patient characteristics, and biochemical factors were analyzed to identify associations with BMD.

RESULTS

After 14 months, in 76 patients, BMD of the lumbar spine had significantly increased (from 0.9 g/cm² to 0.92 g/cm², p<0.001), whereas BMD of the hip and femoral neck had not. Multiple linear regression analysis showed that HCV infection was negatively associated with BMD change in the lumbar spine ( β: -0.247, 95% CI, -0.035 to -0.002; p = 0.028). Moreover, in subgroup analysis, among 42 patients without alendronate, multiple linear regression analysis showed HCV infection was a risk factor for adverse BMD change of the lumbar spine ( β: -0.371, 95% CI, -0.043 to -0.003; p = 0.023).

CONCLUSION

HCV infection in renal transplant recipients was a negative risk factor for BMD change in the lumbar spine. Moreover, alendronate may be able to reverse the negative effect of HCV infection on bone in renal transplant recipients.

Vitamin D for your patients with chronic hepatitis C?

Vitamin D is increasingly becoming recognized as an important physiological regulator with pleiotropic functions outside of its classical role in skeletal homeostasis. A growing body of clinical evidence highlights the prevalence and risks of vitamin D deficiency in patients suffering from chronic hepatitis C infection, and vitamin D supplementation has been proposed as an adjunct to current standards of care. This review considers the experimental evidence for the anti-inflammatory, antifibrotic and antiviral effects of vitamin D, and discusses the therapeutic potential of vitamin D supplementation to protect against liver disease progression and improve responses to treatment.

HIV infection and osteoporosis: pathophysiology, diagnosis, and treatment options

As the population with HIV continues to age, specialists in HIV care are increasingly encountering chronic health conditions, which now include osteoporosis, osteopenia, and fragility fractures. The pathophysiology of the bone effects of HIV infection is complex and includes traditional risk factors for bone loss as well as specific effects due to the virus itself, chronic inflammation, and HAART. Examining risk factors for low bone density and screening of certain patients is suggested, and consideration should be given to treatment for those considered high risk for fracture.

Osteoporosis and bone health in HIV

Patients with HIV can develop several complications that involve bone including low bone mineral density and osteoporosis, osteonecrosis, and rarely osteomalacia. Low bone mineral density leading to osteoporosis is the most common bone pathology. This may result from HIV infection (directly or indirectly), antiretroviral toxicity, or as a consequence of other co-morbidities. The clinical relevance of osteoporosis in HIV infection has been uncertain; however, fragility fractures are increasingly reported in HIV-infected patients. Further research is required to understand the pathogenesis of osteoporosis in HIV-infected patients and determine effective management; however, initiation of antiretroviral therapy seems to accelerate (in the short-term) bone demineralization. Tenofovir may be associated with a greater degree of short-term loss of bone density than other antiviral agents and the potential long-term bone dysfunction is unclear. As the HIV-infected population ages, screening for low bone mineral density will become increasingly important.

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.

The combination of FRAX and Ageing Male Symptoms scale better identifies treated HIV males at risk for major fracture

OBJECTIVE

Osteoporosis and hypogonadism are common in men with HIV infection. Ageing Male Symptoms (AMS) scale measures symptoms related to hypogonadism. FRAX provides 10-year probability of major fractures. We investigated the role of AMS scale combined with FRAX without bone mineral density (BMD), in identifying HIV men with bone fragility.

DESIGN

Cross-sectional observational study.

METHODS

Fifty HIV-positive men treated with highly active antiretroviral therapy and 27 controls underwent hormonal evaluation, BMD scan and spine X-ray. The AMS questionnaire was administered.

RESULTS

Osteoporosis was found in 24·0% of HIV patients and in 3·7% of controls (P = 0·05). In HIV patients, 9 radiological vertebral fractures were found (none in controls, P = 0·04). Calculated free testosterone suggested hypogonadism in 26% of HIV patients vs 4% of controls (P = 0·04); an abnormal AMS score (≥27) was found in 62% HIV patients compared with 41% controls (P = 0·04). ROC curves showed that FRAX for major fracture had a 23% sensitivity and a 100% specificity in identifying HIV patients with bone fragility (P = 0·002, with the threshold of 7% at which bisphosphonate therapy is cost-effective). Considering a value of AMS ≥27, we obtained an 82·6% sensitivity and a 42·9% specificity (P = 0·04). The combination of AMS and FRAX score achieved a 77·3% sensitivity and a 69% specificity (P = 0·02, cut-off 34).

CONCLUSION

Combination of FRAX (without BMD) and AMS improved sensitivity of FRAX alone in identifying HIV patients at fracture risk, at the expense of reduced specificity.

Hyperparathyroidism and complications associated with vitamin D deficiency in HIV-infected adults in New York City, New York

Although recent studies report a high prevalence of vitamin D deficiency in HIV-infected adults similar to that in the general population, metabolic complications of vitamin D deficiency may be worsened with HIV infection and remain insufficiently characterized. We conducted a retrospective cross-sectional cohort study to determine prevalence and correlates of vitamin D deficiency and hyperparathyroidism among HIV-infected patients attending an urban clinic. Vitamin D deficiency was defined as 25(OH)-vitamin D <20 ng/ml and insufficiency as 20 to <30 ng/ml, and hyperparathyroidism as parathyroid-hormone >65 pg/ml. We used the X(2) test to compare proportions and logistic regression to assess for associations. Among 463 HIV-infected patients, the prevalence of vitamin D deficiency was 59%. The prevalence of hyperparathyroidism was 30% among patients with vitamin D deficiency, 23% among those with insufficiency, and 12% among those with sufficient vitamin D levels. Vitamin D deficiency was associated with increased odds of hyperparathyroidism. Severe vitamin D deficiency was associated with elevated alkaline phosphatase, a marker for increased bone turnover. Although efavirenz use was associated with vitamin D deficiency, and protease inhibitor use with decreased odds of vitamin D deficiency, there was no statistical difference in rates of hyperparathyroidism stratified by combination antiretroviral therapy (cART) use. Given the increased risk of osteopenia with HIV infection and cART use, vitamin D supplementation for all HIV-infected patients on cART should be prescribed in accordance with the 2011 Endocrine Society guidelines. In HIV-infected patients with severe vitamin D deficiency or hyperparathyroidism, screening for osteomalacia and osteopenia may be warranted.

Hip bone geometry in HIV/HCV-co-infected men and healthy controls

People with both HIV and hepatitis C are more likely than those with HIV alone to have wrist, hip, and spine fractures. We compared hip strength between HIV/HCV-co-infected men and healthy men and found that HIV/HCV-co-infected men had decreased hip strength due to lower lean body mass.

INTRODUCTION

Hepatitis C co-infection is a risk factor for fragility fracture among HIV-infected populations. Whether bone strength is compromised in HIV/HCV-co-infected patients is unknown.

METHODS

We compared dual-energy x-ray absorptiometry (DXA)-derived hip geometry, a measure of bone strength, in 88 HIV/HCV-co-infected men from the Johns Hopkins HIV Clinic to 289 men of similar age and race and without HIV or HCV from the Boston Area Community Health Survey/Bone Survey. Hip geometry was assessed at the narrow neck, intertrochanter, and shaft using hip structural analysis. Lean body mass (LBM), total fat mass (FM), and fat mass ratio (FMR) were measured by whole-body DXA. Linear regression was used to identify body composition parameters that accounted for differences in bone strength between cohorts.

RESULTS

HIV/HCV-co-infected men had lower BMI, LBM, and FM and higher FMR compared to controls (all p < 0.05). At the narrow neck, significant differences were observed between HIV/HCV-co-infected men and controls in bone mineral density, cross-sectional area, section modulus, buckling ratio, and centroid position. After adjustment for race, age, smoking status, height, and weight, only buckling ratio and centroid position remained significantly different between cohorts (all p < 0.05). Substituting LBM, FM, and FMR for weight in the multivariate model revealed that differences in LBM, but not FM or FMR, accounted for differences in all narrow neck parameters between cohorts, except buckling ratio and centroid position.

CONCLUSION

HIV/HCV-co-infected men have compromised hip strength at the narrow neck compared to uninfected controls, which is attributable in large part to lower lean body mass.

Use of dual-energy x-ray absorptiometry (DXA) scans in HIV-infected patients

Multiple studies have demonstrated increased rates of osteopenia and osteoporosis in HIV-infected patients but there have been no published studies on current screening practices. We conducted a retrospective chart review of 2924 patients attending an urban HIV clinic. Thirty patients (1%) had dual-energy x-ray absorptiometry (DXA) scans. Patients undergoing DXA scans were more likely to be older, women, and have nondetectable HIV viral load and CD4 count ≥200. The most frequently cited indications for screening were perimenopausal or postmenopausal status and HIV infection. Of the patients screened, 96% had osteopenia or osteoporosis with a median T-score of -1.9 and a median of 3.8 osteoporosis risk factors in addition to HIV.  Of the 20 practitioners in the clinic, only 7 had patients with screening DXA scans. DXA scans are underutilized in the HIV population given the high rate of osteopenia and osteoporosis detected in this study.

The frequency of low muscle mass and its overlap with low bone mineral density and lipodystrophy in individuals with HIV--a pilot study using DXA total body composition analysis

As a result of the advances in antiretroviral therapy, the life span of human immunodeficiency virus (HIV)-infected patients has increased dramatically. Attendant to these effects are signs of premature aging with notable changes in the musculoskeletal system. Although changes in bone and fat distribution have been studied extensively, far less is known about changes in muscle. This study examined the extent of low muscle mass (LMM) and its relationship with low bone mineral density (BMD) and lipodystrophy (LD) in HIV-positive males. As such, HIV-positive males on therapy or treatment naive underwent dual-energy X-ray absorptiometry total body composition measurements. Appendicular lean mass/(height)2 and lowest 20% of residuals from regression analysis were used to define LMM. BMD criteria defined osteopenia/osteoporosis, and the percent central fat/percent lower extremity ratio defined LD. Several potential risk factors were assessed through chart review. Sixty-six males (57 with treatment and 9 treatment naive) volunteered. Treated individuals were older than naive (44 vs 34 yr) and had HIV longer (108 vs 14 mo). When definitions for sarcopenia (SP) in elderly individuals were applied, the prevalence of LMM was 21.9% and 18.8% depending on the definition used. Low BMD was present in 68.2% of participants. LD with a cutoff of 1.5 and 1.961 was present in 54.7% and 42.2% of participants, respectively. LMM and LD were negatively associated. In conclusion, this study shows that LMM is common in males with HIV and that SP affecting muscle function could be present in a substantial number of individuals. Future research needs to examine what impact decreased muscle mass and function has on morbidity, physical function, and quality of life in individuals with HIV.

Effects of vitamin D deficiency and combination antiretroviral therapy on bone in HIV-positive patients

OBJECTIVES

In the era of combination antiretroviral therapy (cART), vitamin D deficiency, low bone mineral density (BMD) and fractures have emerged as subjects of concern in HIV-positive patients. Testing for vitamin D deficiency has been widely adopted in clinical practice even though the benefits of vitamin D supplementation in this population remain uncertain. The objective of this review was to evaluate the evidence for such a strategy.

DESIGN

Systematic review of the literature on vitamin D deficiency in HIV infection, the effects of cART on vitamin D status, and the effects of vitamin D deficiency and cART on parathyroid hormone (PTH), bone turnover, BMD and the incidence of fractures in HIV-positive patients.

METHODS

PubMed was used to identify relevant articles up to September 2011.

RESULTS

Vitamin D deficiency, secondary hyperparathyroidism and low BMD are common in HIV-positive patients. Efavirenz is associated with a reduction in 25-hydroxy vitamin D levels, tenofovir with secondary hyperparathyroidism, and cART with increased bone turnover and low BMD. The clinical significance of low BMD, however, remains unclear, especially in younger patients. Although the incidence of fractures may be increased in HIV-positive patients, the contribution of low BMD and vitamin D deficiency to these fractures is uncertain. Limited data on vitamin D supplementation in HIV-positive patients have shown transient, beneficial effects on PTH, but no effects on BMD.

CONCLUSION

The benefits of vitamin D supplementation in this population need to be demonstrated before widespread 'test and treat' policies can be recommended as part of routine clinical practice.

Low CD4 count is associated with an increased risk of fragility fracture in HIV-infected patients

BACKGROUND

Low bone mineral density in HIV-infected patients is an increasingly recognized clinical problem. The aim of this study was to determine the incidence, prevalence, and risk factors for development of low trauma or fragility fractures in an HIV-infected population.

METHODS

A 1:2 matched case-control study was performed of HIV-infected patients attending the Alfred Hospital between 1998 and 2009. Controls were matched on gender, age, and duration of HIV infection.

RESULTS

The overall fracture incidence rate was 0.53 per 100 person-years [95% confidence interval (CI): 0.43 to 0.65] and period prevalence of 3.34 per 100 patients (95% CI: 2.66 to 4.13). There were 73 low trauma fractures in 61 patients. Patients were predominantly male (89%) with a mean age of 49.8 years. Independent risk factors for fragility fracture were a CD4 cell count <200 cells per microliter odds ratio (OR): 4.91 (95% CI: 1.78 to 13.57, P = 0.002), corticosteroids OR: 8.96 (95% CI: 1.55 to 51.88, P = 0.014) and anti-epileptic medications OR: 8.88 (95% CI: 1.75 to 44.97, P = 0.008). There were no significant associations between HIV viremia (P = 0.18), use of or class of antiretroviral medication, and risk of fracture. Eighty-eight percent of patients with fracture had established osteopenia or osteoporosis.

CONCLUSION

This is the largest clinical study to date of fragility fractures occurring in an HIV-infected population. The study found that risk of fracture was strongly associated with a low CD4 cell count, use of corticosteroids, and anti-epileptic medications. There were no associations between fracture risk and viral load, use of class, or duration of antiretroviral agent.

Controlled HIV viral replication, not liver disease severity associated with low bone mineral density in HIV/HCV co-infection

BACKGROUND & AIMS

To evaluate the prevalence and risk factors for low bone mineral density (BMD) in persons co-infected with HIV and Hepatitis C.

METHODS

HIV/HCV co-infected study participants (n=179) were recruited into a prospective cohort and underwent dual-energy X-ray absorptiometry (DXA) within 1 year of a liver biopsy. Fibrosis staging was evaluated according to the METAVIR system. Osteoporosis was defined as a T-score ≤-2.5. Z-scores at the total hip, femoral neck, and lumbar spine were used as the primary outcome variables to assess the association between degree of liver disease, HIV-related variables, and BMD.

RESULTS

The population was 65% male, 85% Black with mean age 50.3 years. The prevalence of osteoporosis either at the total hip, femoral neck, or lumbar spine was 28%, with 5% having osteoporosis of the total hip, 6% at the femoral neck, 25% at the spine. The mean Z-scores (standard deviation) were -0.42 (1.01) at the total hip, -0.16 (1.05) at the femoral neck, and -0.82 (1.55) at the lumbar spine. In multivariable models, controlled HIV replication (HIV RNA <400 copies/ml vs. ≥400 copies/ml) was associated with lower Z-scores (mean ± standard error) at the total hip (-0.44 ± 0.17, p = 0.01), femoral neck (-0.59 ± 0.18, p = 0.001), and the spine (-0.98 ± 0.27, p = 0.0005). There was no association between degree of liver fibrosis and Z-score.

CONCLUSIONS

Osteoporosis was very common in this population of predominately African-American HIV/HCV co-infected patients, particularly at the spine. Lower BMD was associated with controlled HIV replication, but not liver disease severity.

Bone mineral density and fractures in antiretroviral-naive persons randomized to receive abacavir-lamivudine or tenofovir disoproxil fumarate-emtricitabine along with efavirenz or atazanavir-ritonavir: Aids Clinical Trials Group A5224s, a substudy of ACTG A5202

BACKGROUND

Long-term effects of abacavir (ABC)-lamivudine (3TC), compared with tenofovir (TDF)-emtricitabine (FTC) with efavirenz (EFV) or atazanavir plus ritonavir (ATV/r), on bone mineral density (BMD) have not been analyzed.

METHODS

A5224s was a substudy of A5202, in which HIV-infected treatment-naive participants were randomized and blinded to receive ABC-3TC or TDF-FTC with open-label EFV or ATV/r. Primary bone end points included Dual-emission X-ray absorbtiometry (DXA)-measured percent changes in spine and hip BMD at week 96. Primary analyses were intent-to-treat. Statistical tests used the factorial design and included linear regression, 2-sample t, log-rank, and Fisher's exact tests.

RESULTS

Two hundred sixty-nine persons randomized to 4 arms of ABC-3TC or TDF-FTC with EFV or ATV/r. At baseline, 85% were male, and 47% were white non-Hispanic; the median HIV-1 RNA load was 4.6 log(10) copies/mL, the median age was 38 years, the median weight was 76 kg, and the median CD4 cell count was 233 cells/μL. At week 96, the mean percentage changes from baseline in spine and hip BMD for ABC-3TC versus TDF-FTC were -1.3% and -3.3% (P = .004) and -2.6% and -4.0% (P = .024), respectively; and for EFV versus ATV/r were -1.7% and -3.1% (P = .035) and -3.1% and -3.4% (P = .61), respectively. Bone fracture was observed in 5.6% of participants. The probability of bone fractures and time to first fracture were not different across components.

CONCLUSIONS

Compared with ABC-3TC, TDF-FTC-treated participants had significantly greater decreases in spine and hip BMD, whereas ATV/r led to more significant losses in spine, but not hip, BMD than EFV. Clinical Trials Registration. NCT00118898.

Prevention of bone loss and management of fracture risk in HIV-infected individuals: case studies and recommendations for different patient subgroups

Increased life-expectancy and the need for long-term antiretroviral therapy have brought new challenges to the clinical management of HIV-infected individuals. While the prevalence of osteoporosis and fractures is probably increased in HIV-infected patients, optimal strategies for risk assessment and treatment in this relatively young population are yet to be defined. Prevention of bone loss is likely to become an important component of HIV care as the HIV-infected patient population grows older. In this article, we present an overview of the literature on bone loss in individuals with HIV and discuss the practical application of the European AIDS Clinical Society (EACS) guidelines to a range of clinical case scenarios.

HIV and bone metabolism

The skeleton is an organ whose integrity is maintained by constant lifelong renewal involving coordinated removal of worn bone by osteoclasts and resynthesis of new bone by osteoblasts. In young adult humans and animals this process is homeostatic with no net gain or loss of bone mass. With natural aging and exacerbated by numerous pathological conditions, bone removal exceeds bone formation, disrupting homeostasis and resulting in bone loss. Over time, skeletal decline reaches clinical significance with development of osteopenia and eventually osteoporosis, conditions that dramatically increase bone fragility and the risk of fracture. Bone fractures can be devastating with significant morbidity and mortality. Over the last decade, it has become clear that skeletal renewal is strongly influenced by the immune system, a consequence of deep integration and centralization of common cell types and cytokine mediators, which we have termed the "immuno-skeletal interface." Consequently, dysregulated skeletal renewal and bone loss is a common feature of inflammatory conditions associated with immune activation. Interestingly, bone loss is also associated with conditions of immunodeficiency, including infection by the human immunodeficiency virus (HIV) that leads to acquired immunodeficiency syndrome (AIDS). Disruptions to the immuno-skeletal interface drive skeletal deterioration contributing to a high rate of bone fracture in HIV infection. This review examines current knowledge concerning the prevalence and etiology of skeletal complications in HIV infection, the effect of antiretroviral therapies (ART) on the skeleton, and how disruption of the immuno-skeletal interface may underlie bone loss in HIV infection and ART.

Prospective one-year bone loss in treatment-naïve HIV+ men and women on single or multiple drug HIV therapies

Antiretroviral therapy has decreased the rate of HIV-related mortality and extended the life span of HIV patients. Current guidelines recommend the use of a 3-drug regimen, such as two nucleoside reverse transcriptase inhibitors and a protease inhibitor, boosted by ritonavir. Osteoporosis can be associated with the HIV disease itself or with antiretroviral therapy. Many trials have been conducted employing a single drug regimen to simplify antiretroviral therapy but few studies assessed the effect of the single drug regimen on bone mineral density (BMD). The objectives of the study were to assess and compare the relative (%) changes in lumbar spine and hip BMD over 48 weeks in HIV patients treated with mono or triple antiretroviral regimens The study was conducted using data from a randomized trial (MONARK) conducted in 136 antiretroviral-naïve HIV patients (89 men and 47 women) comparing the antiviral efficacy of a single-drug protease inhibitor regimen of lopinavir/ritonavir (LPV/r) versus LPV/r in combination with zidovudine (ZDV) and lamivudine (3TC). Lumbar spine and total hip BMD were assessed in 100 patients by dual-energy X-ray absorptiometry at baseline and 48 weeks. 48 week-BMD data were available for 43 patients (mean age 37years) with a mean baseline lumbar spine Z-score of -0.1 in the LPV/r monotherapy group and for 25 patients (mean age 35.8years) with a mean baseline lumbar spine Z-score of -0.2 in the LPV/r+ZDV+3TC group. After 48weeks, lumbar spine BMD significantly decreased by 4.4% (-5.1% to -2.1%, P≤0.001) in the LPV/r group and by 4.0% (-5.0% to -1.7%, P≤0.0001) in the LPV/r+ZDV+3TC group. There was no significant difference in BMD changes between the two groups. These results suggest that bone loss is observed 48 weeks after the initiation of antiretroviral therapy, whether the patients receive a single- or triple-drug antiretroviral regimen.

High frequency of poor locomotor performance in HIV-infected patients

OBJECTIVES

To provide up-to-date assessments of locomotor function in HIV-infected patients and to identify potential determinants of impaired function.

DESIGN

Cross-sectional study in 324 HIV-1-infected adults from the French Agency for AIDS and Hepatitis Research (ANRS) CO3 Aquitaine Cohort using standardized locomotor tests.

METHODS

Patients underwent standardized testing assessing balance, walking ability, functional capacity and lower limb muscle performance. Poor test performance was defined by cut-offs based on age-specific data of the general population. Factors associated with poor test performance were studied by logistic regression.

RESULTS

Median age was 48 years, 80% were men and 89% were on antiretroviral treatment. The most frequently altered locomotor test was the five-times sit-to-stand (5STS) test, assessing lower limb muscle performance (poor performance: 53%). In multivariable analysis, time since HIV diagnosis was associated with poor 5STS performance [odds ratio (OR) = 1.08 per year; 95% confidence interval (CI): 1.03, 1.13]. In patients below 30 years, elevated BMI was associated with higher likelihood of good performance (OR = 0.81 per kg/m(2); 95% CI: 0.69, 0.93), whereas in those above 70 years this association was reversed (OR = 1.30 per kg/m(2); 95% CI: 1.10, 1.53; P < 10(-3) for interaction). We found no association with antiretroviral treatment.

CONCLUSION

One of two adults with controlled HIV infection had poor lower limb muscle performance, which might put this population at risk of falls and fracture. The 5STS test is a simple test that should be recommended to assess muscular performance in HIV care.

Increased rates of bone fracture among HIV-infected persons in the HIV Outpatient Study (HOPS) compared with the US general population, 2000-2006

BACKGROUND

Among persons with HIV infection, low bone mineral density is common and has raised concerns about increased risk of fracture.

METHODS

We analyzed data from the HIV Outpatient Study (HOPS), an open prospective cohort study of HIV-infected adults who were followed up at 10 US HIV clinics. We assessed rates of first fractures at any anatomic site during the period 2000-2008. We indirectly standardized the rates of fracture in the HOPS to the general population by age and sex, using data from outpatients in the National Hospital Ambulatory Medical Care Survey (NHAMCS-OPD). We examined factors associated with fractures using Cox proportional hazards modeling.

RESULTS

Among 5826 active HOPS patients whose data were analyzed (median baseline age, 40 years; male sex, 79%; white race, 52%; exposure to antiretroviral therapy, 73%), 233 patients had incident fractures (crude annual rates, 59.6-93.5 fractures per 10,000 persons). Age-standardized fracture rates increased from 2000 to 2002 (P = .01) and stabilized thereafter. Among persons aged 25-54 years, both fracture rates and relative proportion of fragility fractures were higher among HOPS patients than among patients in the NHAMCS-OPD. In addition to older age and substance abuse, nadir CD4+ cell count <200 cells/mm(3) (adjusted hazard ratio [aHR], 1.60; 95% confidence interval [CI], 1.11-2.31), hepatitis C infection (aHR, 1.61; 95% CI, 1.13-2.29) and diabetes (aHR, 1.62; 95% CI, 1.00-2.64) were associated with incident fractures.

CONCLUSIONS

Age-adjusted fracture rates among HOPS patients were higher than rates in the general US population during the period 2000-2006. Clinicians should regularly assess HIV-infected persons for fracture risk, especially those with low nadir CD4+ cell counts or other established risk factors for fracture.

HIV/HCV co-infection: pathogenesis, clinical complications, treatment, and new therapeutic technologies

World-wide, hepatitis C virus (HCV) accounts for approximately 130 million chronic infections, with an overall 3% prevalence. Four to 5 million persons are co-infected with HIV. It is well established that HIV has a negative impact on the natural history of HCV, including a higher rate of viral persistence, increased viral load, and more rapid progression to fibrosis, end-stage liver disease, and death. Whether HCV has a negative impact on HIV disease progression continues to be debated. However, following the introduction of effective combination antiretroviral therapy, the survival of coinfected individuals has significantly improved and HCV-associated diseases have emerged as the most important co-morbidities. In this review, we summarize the newest studies regarding the pathogenesis of HIV/HCV coinfection, including effects of coinfection on HIV disease progression, HCV-associated liver disease, the immune system, kidney and cardiovascular disease, and neurologic status; and effectiveness of current anti-HIV and HCV therapies and proposed new treatment strategies.

Increased risk of fragility fractures among HIV infected compared to uninfected male veterans

Background

HIV infection has been associated with an increased risk of fragility fracture. We explored whether or not this increased risk persisted in HIV infected and uninfected men when controlling for traditional fragility fracture risk factors.

Methodology/Principal Findings

Cox regression models were used to assess the association of HIV infection with the risk for incident hip, vertebral, or upper arm fracture in male Veterans enrolled in the Veterans Aging Cohort Study Virtual Cohort (VACS-VC). We calculated adjusted hazard ratios comparing HIV status and controlling for demographics and other established risk factors. The sample consisted of 119,318 men, 33% of whom were HIV infected (34% aged 50 years or older at baseline, and 55% black or Hispanic). Median body mass index (BMI) was lower in HIV infected compared with uninfected men (25 vs. 28 kg/m²; p<0.0001). Unadjusted risk for fracture was higher among HIV infected compared with uninfected men [HR: 1.32 (95% CI: 1.20, 1.47)]. After adjusting for demographics, comorbid disease, smoking and alcohol abuse, HIV infection remained associated with an increased fracture risk [HR: 1.24 (95% CI: 1.11, 1.39)]. However, adjusting for BMI attenuated this association [HR: 1.10 (95% CI: 0.97, 1.25)]. The only HIV-specific factor associated with fragility fracture was current protease inhibitor use [HR: 1.41 (95% CI: 1.16, 1.70)].

Conclusions/Significance

HIV infection is associated with fragility fracture risk. This risk is attenuated by BMI.

HIV infection and bone disease: implications for an aging population

Now more than ever, the management of age-related problems, from cardiovascular morbidity to bone pathology, is increasingly relevant for HIV physicians. Low bone mineral density (BMD) and fractures are more common in HIV-infected patients. Although a multifactorial aetiology underlies this condition, increasing evidence suggests a role for antiretroviral therapy in low BMD, especially upon initiation. This review will detail the epidemiology, pathogenesis, diagnosis and management of osteoporosis and low BMD in HIV-infected patients, with particular emphasis on aging.

Fracture incidence in HIV-infected women: results from the Women's Interagency HIV Study

BACKGROUND

The clinical importance of the association of HIV infection and antiretroviral therapy (ART) with low bone mineral density (BMD) in premenopausal women is uncertain because BMD stabilizes on established ART and fracture data are limited.

METHODS

We measured time to first new fracture at any site with median follow-up of 5.4 years in 2391 (1728 HIV-infected, 663 HIV-uninfected) participants in the Women's Interagency HIV Study (WIHS). Self-report of fracture was recorded at semiannual visits. Proportional hazard models assessed predictors of incident fracture.

RESULTS

At baseline, HIV-infected women were older (40 ± 9 vs. 36 ± 10 years, P < 0.0001), more likely to report postmenopausal status and be hepatitis C virus-infected, and weighed less than HIV-uninfected women. Among HIV-infected women, mean CD4(+) cell count was 482 cells/μl; 66% were taking ART. Unadjusted incidence of fracture did not differ between HIV-infected and uninfected women (1.8 vs. 1.4/100 person-years, respectively, P = 0.18). In multivariate models, white (vs. African-American) race, hepatitis C virus infection, and higher serum creatinine, but not HIV serostatus, were statistically significant predictors of incident fracture. Among HIV-infected women, older age, white race, current cigarette use, and history of AIDS-defining illness were associated with incidence of new fracture.

CONCLUSION

Among predominantly premenopausal women, there was little difference in fracture incidence rates by HIV status, rather traditional risk factors were important predictors. Further research is necessary to characterize fracture risk in HIV-infected women during and after the menopausal transition.

Incidence densities in a competing events analysis

Epidemiologists often study the incidence density (ID; also known as incidence rate), which is the number of observed events divided by population-time at risk. Its computational simplicity makes it attractive in applications, but a common concern is that the ID is misleading if the underlying hazard is not constant in time. Another difficulty arises if competing events are present, which seems to have attracted less attention in the literature. However, there are situations in which the presence of competing events obscures the analysis more than nonconstant hazards do. The authors illustrate such a situation using data on infectious complications in patients receiving stem cell transplants, showing that a certain transplant type reduces the infection ID but eventually increases the cumulative infection probability because of its effect on the competing event. The authors investigate the extent to which IDs allow for a reasonable analysis of competing events. They suggest a simple multistate-type graphic based on IDs, which immediately displays the competing event situation. The authors also suggest a more formal summary analysis in terms of a best approximating effect on the cumulative event probability, considering another data example of US women infected with human immunodeficiency virus. Competing events and even more complex event patterns may be adequately addressed with the suggested methodology.

Bone disease in HIV infection: a practical review and recommendations for HIV care providers

Low bone mineral density (BMD) is prevalent in human immunodeficiency virus (HIV)-infected subjects. Initiation of antiretroviral therapy is associated with a 2%-6% decrease in BMD over the first 2 years, a decrease that is similar in magnitude to that sustained during the first 2 years of menopause. Recent studies have also described increased fracture rates in the HIV-infected population. The causes of low BMD in individuals with HIV infection appear to be multifactorial and likely represent a complex interaction between HIV infection, traditional osteoporosis risk factors, and antiretroviral-related factors. In this review, we make the point that HIV infection should be considered as a risk factor for bone disease. We recommend screening patients with fragility fractures, all HIV-infected post-menopausal women, and all HIV-infected men ⩾50 years of age. We also discuss the importance of considering secondary causes of osteoporosis. Finally, we discuss treatment of the more severe cases of bone disease, while outlining the caveats and gaps in our knowledge.

Impact of metabolic complications on antiretroviral treatment adherence: clinical and public health implications

Antiretroviral therapy (ART) is an effective strategy for preventing disease progression of HIV infection, particularly when patients adhere closely to the treatment regimen. However, ART medications can cause side effects, including metabolic complications that can impact patients' adherence levels. Selected chronic complications associated with ART include lipodystrophy, hyperlipidemia, insulin resistance and diabetes, peripheral neuropathy, and bone disorders such as osteopenia/osteoporosis. In this article, we review the effects of these metabolic complications on ART adherence and approaches to prevent or reverse them.