Relationship between low bone mineral density and highly active antiretroviral therapy including protease inhibitors in HIV-infected patients

Bone Tissue Changes in Individuals Living with HIV/AIDS: The Importance of a Hierarchical Approach in Investigating Bone Fragility

Skeletal alterations and their complications can significantly impact the quality of life and overall prognosis of patients living with HIV (PLWHIV). Considering skeletal alterations are often asymptomatic and unapparent during routine clinical evaluation, these conditions are frequently overlooked in the clinical management of PLWHIV. However, since the use of combined antiretroviral therapy (cART) has increased life expectancy in PLWHIV effectively, osteopenia, osteoporosis, and bone fragility are now considered to have a major health impact, with a substantial increase in healthcare costs. This narrative literature review aimed to provide a comprehensive overview of the contemporary literature related to bone changes in PLWHIV, focusing on the importance of taking a multi-scale approach in the assessment of bone hierarchical organization. Even though a low bone mineral density is frequently reported in PLWHIV, numerous ambiguities still remain to be solved. Recent data suggest that assessment of other bone properties (on various levels of the bone structure) could contribute to our understanding of bone fragility determinants in these individuals. Special attention is needed for women living with HIV/AIDS since a postmenopausal status was described as an important factor that contributes to skeletal alterations in this population. Further research on complex etiopathogenetic mechanisms underlying bone alterations in PLWHIV may lead to the development of new therapeutic approaches specifically designed to reduce the health burden associated with skeletal disorders in this population. A major challenge in the clinical management of PLWHIV lies in the adverse skeletal effects of some frequently prescribed cART regimens (e.g., regimens containing tenofovir disoproxil fumarate), which may require a switch to other pharmacological approaches for maintained HIV infection (e.g., regimens containing tenofovir alafenamide). Taken together, the findings are indicative that the HIV/AIDS status should be taken into consideration when designing new guidelines and strategies for individualized prevention, diagnosis, and treatment of increased bone fragility.

Bone, Brain, Heart study protocol: A resilient nested, tripartite prospective cohort study of the role of estrogen depletion on HIV pathology

PURPOSE

We describe the rationale for and design of an innovative, nested, tripartite prospective observational cohort study examining whether relative estrogen insufficiency-induced inflammation amplifies HIV-induced inflammation to cause end organ damage and worsen age-related co-morbidities affecting the neuro-hypothalamic-pituitary-adrenal axis (Brain), skeletal (Bone), and cardiovascular (Heart/vessels) organ systems (BBH Study).

METHODS

The BBH parent study is the Multicenter AIDS Cohort/Women's Interagency HIV Study Combined Cohort Study (MWCCS) with participants drawn from the Atlanta MWCCS site. BBH will enroll a single cohort of n = 120 women living with HIV and n = 60 HIV-negative women, equally distributed by menopausal status. The innovative multipart nested study design of BBH, which draws on data collected by the parent study, efficiently leverages resources for maximum research impact and requires extensive oversight and management in addition to careful implementation. The presence of strong infrastructure minimized BBH study disruptions due to changes in the parent study and the COVID-19 pandemic.

CONCLUSION

BBH is poised to provide insight into sex and HIV associations with the neuro-hypothalamic-pituitary-adrenal axis, skeletal, and cardiovascular systems despite several major, unexpected challenges.

Bone methabolic disorders in HIV positive patients: a case report

Fractures in patients affected by HIV are more frequent than what is reported in patients with no retroviral diseases. Chronic infection with HIV likely contributes to increased systemic inflammation, which has been associated with increased rates of fracture. We report a case of a 56-year-old male (HIV + in treatment with Atripla) heavy worker, at the beginning affected by intra-articular proximal humerus fracture treated with endoprosthesis replacement and later by periprosthetic fracture treated with plate, screws and cerclages. Follow up was performed with clinical evaluation (ROM, VAS, Quick Dash, ASES, Simple shoulder test, UCLA Score, Constant score) and shoulder radiographs. Bone metabolism disorders in HIV patients lead to low BMD values, changes in bone turnover markers, and histomorphometric abnormalities, especially when HIV is present along with HCV or other hepatopathies. Additional therapy with bisphosphonate and Vitamin D should always be carried out when possible to prevent such types of orthopaedic complications. (www.actabiomedica.it)

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

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

Morphological analysis of the skeletal development in lateral cephalometric radiographs of HIV infected children ongoing Highly Active Antiretroviral Therapy

Background

To investigate the skeletal development of HIV infected children through a morphological analysis of the cervical vertebrae (CV) in lateral cephalometric radiographs.

Material and Methods

The sample consisted of 86 lateral cephalometric radiographs of male and female children aged between 6 and 14 years old. The radiographs were equally distributed in groups 1 (HIV infected children) and 2 (non-infected children, paired by sex and age). Two examiners analyzed the CV according to the method of Hassel and Farman (1995). Spearman correlation coefficient was used to associate age and skeletal development within groups, while Mann-Whitney test compared the skeletal development between groups.

Results

The correlation of age and skeletal development in group 1 reached 0.17, 0.27 and 0.27 (p >0.05) for C2, C3 and C4, respectively, while in group 2 it reached 0.65, 0.54 and 0.60, respectively (p <0.001). Differences were not significant between groups (p >0.05).

Conclusions

HIV infected and non-infected children showed a similar development of the CV. However, the weak correlation between age and CV development in HIV infected children highlights the need for careful decisions prior to therapeutic approaches – especially those founded on the prediction of skeletal development, such as maxillofacial surgeries, and orthopedic and orthodontic procedures.

Key words:Cervical vertebrae, growth and development, HIV, radiology.

Ageing with HIV

The population of people living with HIV (PLWH) is growing older with an estimated 4 million over the age of 50 years, a figure which has doubled since the introduction of effective antiretroviral therapy (ART) and which is increasing globally. Despite effective ART, PLWH still experience excess morbidity and mortality compared to the general population with increased prevalence of age-related, non-AIDS illnesses (NAI) such as cardiovascular disease, malignancies, cognitive impairment and reduced bone mineral density, which impact disability and everyday functioning. This review will discuss the challenges presented by comorbidities in ageing PLWH and discuss the aetiology and management of age-related illnesses in this vulnerable population.

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.

Perspectives on menopause and women with HIV

Since the implementation of effective combination antiretroviral therapy, HIV infection has been transformed from a life-threatening condition into a chronic disease. As people with HIV are living longer, aging and its associated manifestations have become key priorities as part of HIV care. For women with HIV, menopause is an important part of aging to consider. Women currently represent more than one half of HIV-positive individuals worldwide. Given the vast proportion of women living with HIV who are, and will be, transitioning through age-related life events, the interaction between HIV infection and menopause must be addressed by clinicians and researchers. Menopause is a major clinical event that is universally experienced by women, but affects each individual woman uniquely. This transitional time in women's lives has various clinical implications including physical and psychological symptoms, and accelerated development and progression of other age-related comorbidities, particularly cardiovascular disease, neurocognitive dysfunction, and bone mineral disease; all of which are potentially heightened by HIV or its treatment. Furthermore, within the context of HIV, there are the additional considerations of HIV acquisition and transmission risk, progression of infection, changes in antiretroviral pharmacokinetics, response, and toxicities. These menopausal manifestations and complications must be managed concurrently with HIV, while keeping in mind the potential influence of menopause on the prognosis of HIV infection itself. This results in additional complexity for clinicians caring for women living with HIV, and highlights the shifting paradigm in HIV care that must accompany this aging and evolving population.

HIV infection and osteoporosis

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

Bone mineral density changes after 2 years of ARV treatment, compared to naive HIV-1-infected patients not on HAART

BACKGROUND

The prevalence of osteopenia and osteoporosis is increased in human immunodeficiency virus (HIV)-infected patients. The pathogenesis of this low bone mineral density (BMD) is multifactorial.

METHODS

We conducted a prospective study over a 2-year period of the BMD in non-treated ARV-naïve HIV-infected-males, in comparison to HIV-infected males commencing a first ARV treatment, and analyzed the evolution of bone turnover markers.

RESULTS

A total of 39 caucasian males (median age 38.6 years) were enrolled, including 10 who started ARV treatment (group 1), and 29 without indications for ARV therapy (group 2). In the latter group, 11 subjects commenced ARV during the study; therefore the remainder of their follow-up was within group 1, which finally consisted of 21 patients. At baseline, 9 patients (19.5%) had osteoporosis at least at 1 site, while 28 (61%) showed osteopenia. Lower BMD was correlated with tobacco use. Lumbar spine and total hip BMD significantly decreased in group 1 patients after 6 months of treatment, then stabilized (2.4% and 4% loss, respectively, at 24 months), while no significant change in BMD was observed in group 2 subjects. At baseline, one patient had an increased CTX (C-terminal cross-linking telopeptide of type 1 collagen) and all BSAP (bone-specific alkaline phosphatase) results were normal. During follow-up, both CTX and BSAP increased in group 1 patients, while they did not change in group 2.

CONCLUSION

Osteoporosis and osteopenia are frequent in HIV-infected males. After ARV initiation, BMD decreased, and bone turnover markers increased, even though the BMD remained stable in non-treated patients. These results underline the impact of HIV treatment on BMD and bone metabolism.

Osteoporosis and fracture risk associated with HIV infection and treatment

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

Bone turnover and bone mineral density in HIV-1 infected Chinese taking highly active antiretroviral therapy -a prospective observational study

Background

Low bone mass and high bone turnover have been reported in HIV-infected individuals, both as a consequence of HIV infection itself, as well as from treatment with highly active antiretroviral therapy (HAART). The purpose of this study is to evaluate the impact of HAART on bone mineral density and bone turnover in HIV-1 infected Chinese patients.

Methods

Forty HIV-1 infected patients were enrolled in this study; all patients were followed through 48 weeks, and 17 patients completed 96 weeks. Bone mineral density (BMD), procollagen type 1 N-terminal propeptide (P1NP), collagen type 1 cross-linked C-telopeptide (β-CTX), parathyroid hormone (PTH), and 25-OH vitamin D levels were measured at baseline, 48 and 96 weeks. Baseline measurements were compared with an age-, gender-, and BMI-matched healthy control population.

Results

At baseline, raw BMD in the lumbar spine of HIV-1 infected patients was significantly lower than that of healthy controls (1.138 ± 0.112 g/cm² vs. 1.195 ± 0.139 g/cm², p = 0.047). During the first 48 weeks after initiating HAART, BMD of lumbar spine, femoral neck, and total hip decreased significantly in HIV-1 infected patients, with annual percent decline ranging from 1.78-3.28%. However, from week 48 to 96, BMD remained stable. Baseline levels of β-CTX (0.31 ± 0.16 ng/mL vs. 0.42 ± 0.19 ng/mL, p = 0.008) and P1NP (32.96 ± 14.00 ng/mL vs. 55.82 ± 26.87 ng/mL, p = 0.05) were lower in HIV-infected patients compared with controls, respectively. Both β-CTX and P1NP levels increased after onset of HAART until week 48, and remained elevated during the next 48 weeks. 25-OH vitamin D in HIV-infected patients was lower at baseline compared to healthy controls, but this difference was not statistically significant. PTH, however, was higher in HIV patients at baseline, and showed a significant increase throughout the study.

Conclusions

Chinese adults with HIV-1 infection have low bone turnover prior to HAART as well as lower raw BMD of the lumbar spine compared with healthy controls, with further bone loss occurring following the initiation of HAART. The long-term clinical implications of these findings remain unclear at this time.

The Role of Inflammatory Cytokines, the RANKL/OPG Axis, and the Immunoskeletal Interface in Physiological Bone Turnover and Osteoporosis

Although it has long been recognized that inflammation, a consequence of immune-driven processes, significantly impacts bone turnover, the degree of centralization of skeletal and immune functions has begun to be dissected only recently. It is now recognized that formation of osteoclasts, the bone resorbing cells of the body, is centered on the key osteoclastogenic cytokine, receptor activator of NF- κ B ligand (RANKL). Although numerous inflammatory cytokines are now recognized to promote osteoclast formation and skeletal degradation, with just a few exceptions, RANKL is now considered to be the final downstream effector cytokine that drives osteoclastogenesis and regulates osteoclastic bone resorption. The biological activity of RANKL is moderated by its physiological decoy receptor, osteoprotegerin (OPG). New discoveries concerning the sources and regulation of RANKL and OPG in physiological bone turnover as well as under pathological (osteoporotic) conditions continue to be made, opening a window to the complex regulatory processes that control skeletal integrity and the depth of integration of the skeleton within the immune response. This paper will examine the interconnection between bone turnover and the immune system and the implications thereof for physiological and pathological bone turnover.

Reduced bone mineral density among HIV-infected patients in Taiwan: prevalence and associated factors

BACKGROUND

Reduced bone mineral density (BMD) is an emerging threat to the successful long-term management of human immunodeficiency virus (HIV) infection among patients with access to combination antiretroviral therapy (cART). Data on the prevalence and associated factors of reduced BMD in Asian populations remain scarce.

METHODS

From March 2002 to April 2006, a cross-sectional survey was conducted among HIV-infected patients aged ≥ 20 years at the National Taiwan University Hospital. BMD of the lumbar spine was measured with the use of dual-energy X-ray absorptiometry. Osteopenia was defined as a BMD T-score between -1.0 and -2.5, and osteoporosis was defined as a BMD T-score ≤ -2.5. Linear and ordinal logistic regression analyses were performed.

RESULTS

Among 320 patients with a median age of 37.3 years, body mass index (BMI) of 21.4kg/m(2) and 94.4% on cART, osteopenia and osteoporosis were diagnosed in 35.6% and 3.8%, respectively. On multivariate linear analysis, factors associated with reduced BMD were increasing age (p=0.006), longer duration on antiretroviral therapy (p=0.007), and a decreasing BMI (p=0.002). Using ordinal logistic regression, being underweight with a body mass index (BMI)<18.5kg/m(2) was independently associated with reduced BMD (proportional odds ratio, 4.12; 95% confidence interval, 1.93-8.82).

CONCLUSION

Reduced BMD was prevalent among HIV-infected Taiwanese adults on cART. Increased age, lower BMI, and exposure to antiretroviral therapy were significantly associated with decrease of BMD.

Dairy calcium intake and lifestyle risk factors for bone loss in hiv-infected and uninfected Mediterranean subjects

BACKGROUND

Despite the reported high prevalence of osteoporosis in the human immunodeficiency virus (HIV)-population, there have been no previous studies examining dairy calcium intake and bone mineral density (BMD) in HIV-subjects. We assessed the prevalence of low BMD in HIV-infected and uninfected subjects and analyzed the effects of calcium intake, lifestyle and HIV-related risk factors on BMD.

METHODS

One hundred and twelve HIV-infected subjects were consecutively enrolled. Seventy- six HIV-uninfected subjects matched for age and sex were enrolled as the control group. The HIV-subjects were interviewed about lifestyle habits and completed a weekly food-frequency questionnaire to estimate calcium intake. HIV-RNA, CD4+ T-cell count and data on antiretroviral therapy were also recorded. Both biochemical bone turnover markers and BMD, assessed by dual-energy radiographic absorptiometry (DXA) were recorded in the HIV-cases and controls. We also calculated the 10-year fracture risks using the WHO FRAX equation.

RESULTS

Osteoporosis prevalence was significantly higher in the HIV-cases than controls (p < 0.05). BMI values were positively correlated with BMD (p < 0.05). Vitamin D levels were lower in the HIV-subjects (p < 0.02). No correlation was found with daily calcium intake. BMI values were significantly correlated with dairy intake quartiles (p < 0.003). In HIV-subjects, the mean of FRAX score was 1.2 % for hip and 4.7 % for major osteoporotic fractures. On multivariate analysis of the lumbar spine DXA T-score, age (p < 0.005) and HIV/hepatitis C virus co-infection (p < 0.0001) were negatively correlated with BMD, while yogurt intake was a protective predictor of BMD (p < 0.05). In the femur DXA T-score, age (p < 0.01), nadir CD4 + T-cell count < 200 cells/μL (p < 0.05) and drug addiction ( p < 0.0001) were negatively correlated with BMD.

CONCLUSIONS

Among the foods rich in calcium, yogurt was a protective predictor of BMD in HIV-subjects. HIV/HCV co-infection, nadir CD4 + T-cell count < 200 cells/μL and drug addiction were independent predictors of severe BMD. Promoting behavioral changes in food intake and lifestyle, aimed at the primary prevention of bone disease in the chronically-infected subjects seems to be essential for implementing medical intervention in these cases.

HIV medications: an update and review of metabolic complications

In the past 30 years, medical advances for those with human immunodeficiency virus (HIV) have reduced morbidity and mortality to extend life with highly active antiretroviral therapy (HAART) and with the continued development of new therapies. With this success, HIV is being managed chronically, but other health issues of an aging HIV-infected population have emerged. The challenges of treating HIV infection have shifted from AIDS-related mortality improvements to drug-induced disease from HAART, including cardiovascular disease, metabolic disorders, and bone health. Prolonged use of antiretroviral therapy maintaining immune restoration appears to represent additional, ongoing risk factors for the development of these metabolic complications. These drug-related problems continue to challenge patients and clinicians in the management of HIV disease, as well as ongoing research for drug development improvements to minimize these risks. These health risks imposed by HAART must be vigilantly monitored and aggressively addressed to improve the overall health of those treated for HIV infection.

Vitamin D status in young HIV infected women of various ethnic origins: incidence of vitamin D deficiency and possible impact on bone density

BACKGROUND

Decreased bone mineral density (BMD) was reported in HIV infected patients. Mechanisms leading to this decrease are poorly understood.

AIMS

To assess factors relating to BMD in young HIV infected Israeli women of Ethiopian and Caucasian origin.

PATIENTS AND METHODS

75 young HIV infected women aged 34.5 ± 8.5 followed up at the Institute of Allergy, Clinical Immunology & AIDS filled a questionnaire about sun exposure, daily calcium intake and dress habits. Data about HIV status and treatment regimens were collected from the patients' charts. Serum hydroxyvitamin D [25(OH)D] levels, bone turnover markers and bone densitometry were evaluated.

RESULTS

28 (65%) of Ethiopians and 2 (6.25%) of Caucasians had 25(OH)D serum levels <10 ng/ml (vitamin D deficiency), p = 0.001. 21 (67.7%) Ethiopians and 16 (39%) Caucasians avoided sun exposure, p = 0.019. Mean daily calcium intake was 491 ± 268.6 mg and 279 ± 252.6 mg, respectively, p = 0.001. Z scores < -1 found at Lumbar spine in 26 (89.7%), at Femoral neck in 20 (69%) at Total hip in 17 (58.6%) of vitamin D deficient patients compared to 20 (48.8%), 17 (41.5%), 9 (22%), in patients with 25(OH)D > 10 ng/ml, p < 0.01, <0.03, <0.001, respectively. Significantly more Ethiopian than Caucasian women covered their face (32.3% and 9.5%, p = 0.003) and hands (58.1% and 30.9%, p = 0.03). There was no difference in bone turnover markers levels.

CONCLUSION

Poorer vitamin D status was observed in Ethiopian women might be one of the important factors related to lower BMD in this group.

Reduced quantitative ultrasound bone mineral density in HIV-infected patients on antiretroviral therapy in Senegal

BACKGROUND

Bone status in HIV-infected patients on antiretroviral treatment (ART) is poorly documented in resource-limited settings. We compared bone mineral density between HIV-infected patients and control subjects from Dakar, Senegal.

METHODS

A total of 207 (134 women and 73 men) HIV-infected patients from an observational cohort in Dakar (ANRS 1215) and 207 age- and sex-matched controls from the general population were enrolled. Bone mineral density was assessed by quantitative ultrasound (QUS) at the calcaneus, an alternative to the reference method (i.e. dual X-absorptiometry), often not available in resource-limited countries.

RESULTS

Mean age was 47.0 (±8.5) years. Patients had received ART for a median duration of 8.8 years; 45% received a protease inhibitor and 27% tenofovir; 84% had undetectable viral load. Patients had lower body mass index (BMI) than controls (23 versus 26 kg/m(2), P<0.001). In unadjusted analysis, QUS bone mineral density was lower in HIV-infected patients than in controls (difference: -0.36 standard deviation, 95% confidence interval (CI): -0.59;-0.12, P = 0.003). Adjusting for BMI, physical activity, smoking and calcium intake attenuated the difference (-0.27, CI: -0.53;-0.002, P = 0.05). Differences in BMI between patients and controls explained a third of the difference in QUS bone mineral density. Among patients, BMI was independently associated with QUS bone mineral density (P<0.001). An association between undetectable viral load and QUS bone density was also suggested (β = 0.48, CI: 0.02;0.93; P = 0.04). No association between protease inhibitor or tenofovir use and QUS bone mineral density was found.

CONCLUSION

Senegalese HIV-infected patients had reduced QUS bone mineral density in comparison with control subjects, in part related to their lower BMI. Further investigation is needed to clarify the clinical significance of these observations.

Prospective evaluation of bone markers, parathormone and 1,25-(OH)₂ vitamin D in HIV-positive patients after the initiation of tenofovir/emtricitabine with atazanavir/ritonavir or efavirenz

BACKGROUND

Increased risk of fractures and osteoporosis have been associated with the use of antiretroviral drugs. There is a paucity of prospective evaluations of bone markers after the initiation of drugs currently recommended to treat HIV infection and results on the evolution of these markers are conflicting. Lastly, the effect of tenofovir on 1,25-(OH)₂ vitamin D is uncertain.

METHODS

We performed a prospective study on the evolution of bone markers, parathormone and 1,25-(OH)₂ vitamin D before and after standard antiretroviral regimens. This was a sub-study of a trial conducted in antiretroviral-naïve patients randomized to tenofovir + emtricitabine in combination with either atazanavir/ritonavir (ATV/r) or efavirenz (EFV). Follow-up lasted 48 weeks. The following bone markers were analyzed: C-terminal cross-laps (CTx), osteocalcin (OC), osteoprotegerin (OPG), and receptor activator of nuclear factor κB ligand (RANKL). Mixed-factorial analysis of variance with random-coefficient general linear model was used to compare their trends over time and linear multivariable regression was performed with a backward selection method to assess predictors of their variations from baseline to week 48. Trends of parathormone and 1,25-(OH)₂ vitamin D were also evaluated.

RESULTS

Seventy-five patients were studied: 33 received EFV and 42 ATV/r. Significant increases were found for all markers except for RANKL. There was a significant direct association between CTx and OC increases. Multivariable analysis showed that higher glomerular filtration rate (estimated through cystatin C clearance) predicted greater OPG increase, while older age, higher HIV RNA at baseline and use of ATV/r predicted greater CTx increase. A significant increase of parathormone accompanied the evolution of the study markers. 1,25-(OH)₂ vitamin D remained stable, though a seasonality variation was demonstrated.

CONCLUSIONS

These data demonstrate CTx increase (bone resorption marker) corresponding to OC increase (bone formation marker) early upon HAART initiation. Moreover, predictors of bone marker increases have been suggested, possibly indicating that a stricter monitoring of bone health and pro-active interventions are needed in older patients, those with higher HIV RNA, prescribed ATV/r rather than EFV, and with decreased renal function at baseline. Further studies are needed to clarify the mechanisms responsible for up-regulation of bone turnover markers, as well as to understand if and what markers are best correlated or predictive of pathological fractures.

Higher rates of bone loss in postmenopausal HIV-infected women: a longitudinal study

CONTEXT AND OBJECTIVE

The objective of the study was to assess the effects of HIV infection and antiretroviral therapy on change in bone mineral density (BMD) in postmenopausal minority women.

DESIGN, SETTING, AND PATIENTS

We report a longitudinal analysis of change in BMD with a median duration of 15.4 (interquartile range 13.1, 20.7) months in a prospective cohort study of 128 (73 HIV+, 55 HIV-) postmenopausal Hispanic and African-American women.

MAIN OUTCOME MEASURES

Annualized change in BMD by dual-energy x-ray absorptiometry and correlation with baseline markers of bone turnover and serum levels of inflammatory cytokines were measured.

RESULTS

HIV+ women were younger (56 ± 1 vs. 59 ± 1 yr, P < 0.05) and had lower body mass index (BMI; 28 ± 1 vs. 31 ± 1 kg/m(2), P < 0.01). The majority of HIV+ women were on established antiretroviral therapy for more than 3 yr. At baseline, BMD, adjusted for age, race, and BMI, was lower in HIV+ women at the lumbar spine (LS), total hip, and radius and serum C-telopeptide was higher. Annualized rates of bone loss adjusted for baseline BMD were higher in HIV+ women by 2.4-fold at the LS (-1.2 ± 0.3% vs. -0.5 ± 0.3%, P = 0.0009), 3.7-fold at the one third radius (-1.1 ± 0.2% vs. -0.3 ± 0.2, P = 0.006) and 1.7-fold at the ultradistal radius (-1.2 ± 0.2% vs. -0.7 ± 0.2%, P = 0.02). In multivariate analysis, HIV+ status predicted bone loss at the LS, total hip, and ultradistal radius. Among HIV+ women, lower BMI, higher markers of bone turnover levels, and tenofovir were associated with more bone loss.

CONCLUSION

HIV+ postmenopausal minority women had lower BMD, increased bone turnover, and higher rates of bone loss than HIV- women. These features may place these women at increased risk for fracture as they age.

Prospective evaluation of bone mineral density among middle-aged HIV-infected and uninfected women: Association between methadone use and bone loss

OBJECTIVE

We undertook a prospective study to assess the impact of HIV infection on BMD in a cohort of HIV-infected and uninfected women that included illicit drug users, and to measure the contribution of traditional risk factors as well as HIV-related factors to loss of BMD over time.

METHODS

We analyzed BMD at baseline and after ≥18 months in 245 middle-aged HIV-infected and 219 uninfected women, and conducted linear regression analysis to determine factors associated with annual BMD change at the femoral neck, total hip and lumbar spine.

RESULTS

HIV-infected women had lower baseline BMD at the femoral neck and total hip compared with controls; unadjusted rates of BMD change did not differ by HIV status at any site. In multivariable analyses, we found that HIV seropositivity without protease inhibitor (PI) use was associated with BMD decline at the lumbar spine (-.009g/cm(2) per year, p=.03). Additional factors associated with BMD decline were: postmenopausal status, lower BMI, and methadone use at the lumbar spine; postmenopausal status and hepatitis C seropositivity at the femoral neck; and postmenopausal status, age, smoking, and lower BMI at the total hip (all p<.05). Among HIV-infected women, ≥3 years of PI use was associated with an increase in lumbar spine BMD (.013g/cm(2) per year, p=.008).

CONCLUSIONS

Bone loss among HIV-infected middle-aged women was modest, and possibly mitigated by PI use. Methadone use was associated with BMD decline, and should be considered when evaluating women for osteoporosis risk.

Antiretroviral-based microbicides and oral pre-exposure prophylaxis for HIV prevention

Numerous HIV prevention options have been tested, with limited success. Microbicides have been the focus of research specifically targeted to prevent new infections among women. After decades of research using non-HIV-specific microbicides, we now have proof of concept for antiretroviral-based microbicides. Issues of drug resistance, frequency of HIV testing and adherence to treatment remain to be explored. Drugs used for HIV treatment and with good safety profiles have been shown to provide protection to men who have sex with men. Ethical issues surrounding cost, access, future design of HIV prevention trials and composition of the prevention package offered to trial participants remain. The role of advocacy and market research will be crucial to ensure effective interventions are accessed and supported. There is renewed hope in the HIV prevention field with collective efforts needed to ensure we get the new prevention tools and options into the hands of men and women at risk of HIV infection. The purpose of this paper is to provide a review of existing research and identify issues for future enquiry.

The Rapidly Evolving Research on Vitamin D Among HIV-Infected Populations

With ongoing improvement in antiretroviral therapy, mortality among HIV-infected persons has dramatically decreased. For HIV-infected persons who remain engaged in care on suppressive therapy, life expectancy approaches that of the general population. Additionally, we have seen increases in comorbidities traditionally associated with aging: diabetes, hypertension, dyslipidemia, ischemic heart disease, and osteoporosis. Vitamin D deficiency has also been identified as a highly prevalent entity among HIV-infected populations. The association of vitamin D deficiency with several of these comorbidities and its impact on immune function provide the impetus for well-designed studies to evaluate the impact of vitamin D supplementation on HIV disease and antiretroviral therapy. This review summarizes the role of vitamin D in several disease states that are prevalent among HIV populations, with a specific focus on bone health and the interactions with antiretroviral medications.

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.

Endocrine complications of human immunodeficiency virus infection: hypogonadism, bone disease and tenofovir-related toxicity

Treatment with highly active antiretroviral therapy (HAART) has revolutionized care of patients with HIV infection. The cost of increased survival has been antiretroviral toxicity and increasing age-related co-morbidities that include significant metabolic issues. Hypogonadism was first described in the setting of advanced AIDS and can be primary or secondary. Data regarding treatment largely concern patients with wasting. Varied syndromes involving bone have been described in patients with HIV including osteonecrosis, low bone mineral density (BMD) and osteoporosis, and rarely osteomalacia. Low BMD leading to osteoporosis is the most common bone pathology and may be as a result of HIV infection, drug toxicity or co-morbidities. However, increasingly fragility fractures are reported in HIV-infected patients, suggesting bone demineralization in this population is of clinical relevance. Further research is required to understand its pathogenesis and determine effective management; however, initiation of antiretroviral therapy seems to accelerate (in the short-term) bone demineralization. One particular antiretroviral agent, tenofovir is widely used and is potentially implicated as having a greater role in long-term bone and renal dysfunction. As this population ages, screening for low BMD will become increasingly more important.

Bone mineral density in HIV-infected women taking antiretroviral therapy: a systematic review

There is a high prevalence of osteoporosis in HIV-infected patients. Initially described in HIV-positive men, studies have also demonstrated a high prevalence of osteoporosis in HIV-infected women. It would appear that antiretroviral therapy (ART) plays an important role in the pathogenesis of osteoporosis in HIV-infected patients, although little is known about its importance in relation to osteoporosis and fractures in HIV-positive women. The aim of this systematic review was to evaluate the frequency of bone loss, bone mineral density (BMD) and fractures in HIV-positive women taking ART or protease inhibitors (PI). After screening 597 citations from the databases of PubMed, EMBASE and Lilacs, five studies were selected for the review. A difference was demonstrated of over 3% in the BMD at the femoral neck of HIV-positive women taking PI/ART. No difference was registered in the BMD at the lumbar spine between users and non-users of PI/ART. The lack of studies has made it impossible to reach any conclusion regarding the occurrence of fractures.

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.

Prospective study of bone mineral density changes in aging men with or at risk for HIV infection

OBJECTIVE

To investigate rates and predictors of change in bone mineral density (BMD) in a cohort of aging men with or at risk for HIV infection.

DESIGN

A prospective cohort study among 230 HIV-infected and 159 HIV-uninfected men aged at least 49 years.

METHODS

Longitudinal analyses of annual change in BMD at the femoral neck, total hip, and lumbar spine.

RESULTS

At baseline, 46% of men had normal BMD, 42% had osteopenia, and 12% had osteoporosis. Of those men with normal BMD, 14% progressed to osteopenia and 86% continued to have normal BMD. Of the men initially with osteopenia, 12% progressed to osteoporosis and 83% continued to have osteopenia. Osteopenia incidence per 100 person-years at risk was 2.6 for HIV-uninfected men and 7.2 for HIV-infected men; osteoporosis incidence was 2.2 per 100 person-years at risk among men with osteopenia, regardless of HIV status. In multivariable analysis of annual change in BMD at the femoral neck, we found a significant interaction between heroin use and AIDS diagnosis, such that the greatest bone loss occurred with both AIDS and heroin use (adjusted predicted mean annual bone loss 0.0196 g/cm). Hepatitis C virus seropositivity was also associated with femoral neck bone loss (P = 0.04). The interaction between AIDS and heroin use also was associated with bone loss at the total hip, as was current methadone use (P < 0.01).

CONCLUSION

We found an association of heroin use and AIDS with BMD change, suggesting that heroin users with AIDS may be at particular risk for bone loss.

Antiretroviral therapy and bone mineral measurements in HIV-infected youths

Reduced bone mass measurements are often found in HIV-infected youths. Both in vitro and human studies demonstrated a role of antiretroviral treatment in determining bone mass alteration. Nevertheless, the data regarding the responsibility of different antiretroviral drugs on bone health in children and adolescents are highly controversial. The purpose of the current study was to relate antiretroviral treatment to bone mass measurements in a large cohort of HIV-infected children and adolescents. Bone mineral content (BMC) was measured in 86 HIV-infected youths (aged 4.8-22.1 years), and in 194 healthy controls (aged 4.9-21.9 years). Fifteen patients were naive to antiretroviral treatment, 11 were receiving a dual nucleoside reverse transcriptase inhibitor (NRTIs) combination, 32 a protease inhibitor (PI)-based antiretroviral treatment, and 28 a non-nucleoside reverse transcriptase inhibitor (NNRTIs)-based regimen. Comparisons between healthy and HIV-infected children and adolescents have been performed by multiple regression analyses to correct for differences in age, sex, and anthropometric measurements. Patients receiving a PI-based treatment had lumbar spine and whole body BMC values significantly lower than healthy children (P<0.05). BMC measurements of patients on other therapeutic regimens or naive to antiretroviral treatment did not differ significantly from those of healthy children. Among patients receiving a PI-based regimen, those receiving full dose Ritonavir had significantly lower lumbar spine BMC values compared to other patients. Lumbar spine and whole body BMC measurements of patients receiving a Stavudine-containing regimen were lower compared to healthy controls, naive patients, and patients on other antiretroviral regimens. Multivariate analyses showed that patients receiving both Stavudine and full dose Ritonavir had significantly lower BMC values both at the lumbar spine (P=0.0033), and in the whole skeleton (P=0.05). In conclusion, antiretroviral treatment may have a detrimental effect on bone health of HIV-infected youths: the use of Ritonavir full dose alone or in combination with Stavudine is associated to lower bone mass measurements. The use of antiretroviral regimens including these drugs should thus be monitored closely in HIV-infected youths.

Longitudinal study of body composition of 101 HIV men with lipodystrophy: dual-energy X-ray criteria for lipodystrophy evolution

The aim of this study was to define evolution profiles of body composition among human immunodeficiency virus (HIV)-infected men with lipodystrophy. The design is a retrospective analysis using observational data collected longitudinally. We included 101 HIV-infected men with lipodystrophy managed in routine practice and who had 2 dual energy X-ray absorptiometry scans within a minimum interval of 18 mo. Lipodystrophy was defined as a fat mass ratio (FMR, defined as the ratio of the percentage of the trunk fat mass over the percentage of the lower limbs fat mass) equal or superior to 1.5. Patients were classified in "improved" group (IG: increase of lower limbs fat mass >/= 10%) or "nonimproved" group (NIG). Body composition, immunovirological and epidemiological data were collected and compared between the 2 groups. In the whole population, over a 4-yr period, a significant increase was observed for total fat mass, trunk fat mass, and lower limbs fat mass, whereas total lean mass was stable. Total body mineral density decreased. Fifty-nine patients (IG), less exposed to zidovudine than the NIG, had an increase of lower limbs fat mass higher than 10%. But only 13 (22%) regained a normal distribution of fat mass (FMR < 1.5), showing that lipodystrophy was slowly reversible. Among the NIG, 5 patients (11.9%), less exposed to zidovudine and with a higher mean of viral load, reached an FMR below 1.5. It was mainly because of a loss of trunk fat mass, which could be the sign of a lipodystrophy worsening. Lipodystrophy improved for 58.4% of men. The improvement was very slow. Recovery was observed only in patients with an earlier intervention. No correlation was observed between lipodystrophy and total body bone mineral density. The loss of trunk fat mass without gain of lower limbs fat mass may indicate a worsening of HIV disease.

Total body and spinal bone mineral density across Tanner stage in perinatally HIV-infected and uninfected children and youth in PACTG 1045

OBJECTIVE

To characterize total body bone mineral content (BMC) and total body and spinal bone mineral density (BMD) in perinatally HIV-infected and uninfected children/youth across puberty.

DESIGN

HIV-infected (7-24 years) were randomly selected from six strata based on Tanner stage/protease inhibitor use. HIV-uninfected were frequency-matched by Tanner group and sociodemographic background to the HIV-infected.

METHODS

Dual-energy X-ray absorptiometry (DXA) measured BMC and BMD. Linear regression models tested differences in bone outcomes by HIV and the interaction of HIV by Tanner group (1-2, 3-4, 5). Models were performed separately by sex and adjusted for DXA scanner, race/ethnicity, height, age and lean body mass.

RESULTS

HIV-infected (N = 236) and uninfected (N = 143) were comparable on sex and race/ethnicity. HIV-infected were slightly older (median 12.6 versus 11.9 years). In adjusted models, HIV-infected males had significantly lower total body BMC and total body and spinal BMD at Tanner 5, lower BMC at Tanner 3-4 and similar BMC and BMD at Tanner 1-2, compared to HIV-uninfected males. HIV-infected and uninfected girls did not differ significantly on any bone outcome, but there was a marginally significant interaction of HIV and Tanner group for spinal BMD. Kaletra/ritonavir was associated with lower BMC and total body BMD and nevirapine was associated with higher spinal BMD in a model with all HIV-infected.

CONCLUSIONS

Perinatally HIV-infected males showed more evidence of lower bone density especially in the final stage of pubertal development than HIV-infected girls and they may be at increased risk for bone disease during adulthood.

Bone loss in patients with HIV infection

The prognosis of HIV infection has been considerably improved by the introduction of antiretroviral drugs. However, the longer survival times are associated with the emergence of new complications including decreased bone mineral density (BMD) values and/or bone insufficiency fractures. A meta-analysis of studies published between 1966 and 2005 showed bone absorptiometry results indicating osteoporosis in 15% of HIV patients and osteopenia in 52%. Longitudinal studies found no evidence that antiretroviral drug therapy contributed to the occurrence of bone loss. Available data indicate uncoupling with increases in bone resorption markers and decreases in bone formation markers. In addition to conventional risk factors for osteoporotic fractures, factors in HIV-infected patients may include malnutrition (wasting syndrome), hypogonadism, disorders in calcium and phosphate metabolism, and HIV infection per se. In patients with established bone insufficiency, bisphosphonate therapy should be considered. Alendronate in combination with vitamin D and calcium supplementation has been found effective in improving BMD values.

Short-term bone loss in HIV-infected premenopausal women

BACKGROUND

Low bone mineral density (BMD) has been reported in HIV+ women, but less is known about the longitudinal evolution of BMD and fracture incidence.

METHODS

In 100 HIV+ and 68 HIV- premenopausal women in the Women's Interagency HIV Study, BMD was measured by dual energy x-ray absorptiometry at the femoral neck (FN) and lumbar spine (LS) at index visit and after a median of 2.5 years.

RESULTS

In HIV+ women, BMD at index visit was normal but 5% lower at the LS and FN than in HIV- women. Annual percent decrease in BMD did not differ between HIV+ and HIV- women at the LS (-0.8% +/- 0.2% vs -0.4% +/- 0.2%, P = 0.20) or FN (-0.8% +/- 0.3% vs -0.6% +/- 0.3%, P = 0.56) and remained similar after adjustment for age, weight, and BMD at index visit. Among HIV+ women, bone loss was associated with vitamin D deficiency and opiate use but not with use or class of antiretrovirals. Incidence of self-reported fracture was 0.74 per 100 person-years in HIV+ women and similar in HIV- women.

CONCLUSIONS

In premenopausal HIV+ women, index BMD was lower than comparable HIV- women; however, rates of bone loss at the LS and FN were similar over 2.5 years of observation, irrespective of antiretroviral therapy.

Continuous antiretroviral therapy decreases bone mineral density

OBJECTIVES

To assess the effects of antiretroviral therapy (ART) on bone mineral density (BMD) DESIGN: Randomized comparison of continuous ART (viral suppression group; VS) with intermittent ART (drug conservation group; DC) SETTING: Outpatient clinics in the United States, Australia, and Spain.

PARTICIPANTS

Participants in the Strategies for Management of Antiretroviral Therapy (SMART) Body Composition substudy.

MAIN OUTCOME MEASURES

Annual hip and spine BMD by dual-energy radiographic absorptiometry (DXA) and spine BMD by quantitative computed tomography (qCT).

METHODS

Comparisons were by intention-to-treat analysis, using longitudinal models for change in BMD. Risk factors for BMD loss were evaluated.

RESULTS

The 214 participants (median 44 years, 19% female participants, 73% on ART; median T-scores -0.5 total hip, -0.7 spine DXA, -0.9 spine qCT; 98 randomized to VS and 116 to DC) were followed for a mean 2.4 years. With continuous ART, BMD declined per year by 0.8% (hip), 0.4% (spine DXA), and 2.4% (spine qCT). BMD declined significantly less with intermittent ART. Estimated DC minus VS group differences in mean BMD change through follow-up were 1.4% [hip; 95% confidence interval (CI) 0.6-2.3; P = 0.002], 1.3% (spine DXA; 95% CI 0.1-2.4, P = 0.03), and 3.0% (spine qCT; 95% CI 0.8-5.2, P = 0.007). No consistent drug-specific association with BMD decline was found. In the parent study, 10 of 2753 participants in the VS group and two of 2720 in the DC group reported serious fractures (hazard ratio 4.9; 95% CI 1.1-22.5; P = 0.04).

CONCLUSION

Continuous ART is associated with decline in BMD and possibly more fractures relative to intermittent, CD4 cell count-guided ART.

First line zidovudine/lamivudine/lopinavir/ritonavir leads to greater bone loss compared to nevirapine/lopinavir/ritonavir

OBJECTIVE

We studied changes in bone mineral density (BMD) and bone turnover after initiation of combination antiretroviral therapy (cART) and the contribution of zidovudine/lamivudine (ZDV/3TC) in particular.

DESIGN

Randomized clinical trial comparing lopinavir/ritonavir(LPV/r) + ZDV/3TC with LPV/r + nevirapine (NVP) in 50 cART-naive men.

METHODS

Dual energy X-ray absorptiometry (DXA) and quantitative computed tomography scans (QCT) were performed at baseline and 3, 12, and 24 months after cART initiation. Serum 25-hydroxy-vitamin D3, parathyroid hormone (PTH), osteocalcin, and urine deoxypyridinoline (DPD)/creatinine ratio were measured.

RESULTS

BMD decreased rapidly in both femoral neck and lumbar spine after cART initiation. BMD loss during 24 months measured by DXA, but not by QCT, was greater in the ZDV/3TC/LPV/r group compared to the NVP/LPV/r group [femoral neck: -6.3% +/- 1.0% (P < 0.0001) compared to -2.3% +/- 0.9% (P = 0.01), between-group P = 0.0006); lumbar spine: -5.1% +/- 0.8% (P < 0.0001) compared to -2.6% +/- 0.7% (P = 0.0006), between-group P = 0.07]. Osteocalcin [+1.60 +/- 0.32 (P < 0.0001) and +1.81 +/- 0.29 (P < 0.0001) nmol/l] and the urine DPD/creatinine ratio [+1.35 +/- 0.44 (P = 0.0029) and +1.19 +/- 0.38 nmol/mmol (P = 0.0024)] increased in both groups over 24 months, with no significant difference between groups. PTH increased to a greater degree in the NVP/LPV/r group [+2.0 +/- 0.31 pmol/l (P < 0.0001)] compared to [+0.81 +/- 0.33 pmol/l (P = 0.021) in the ZDV/3TC/LPV/r group].

CONCLUSION

BMD in both femoral neck and lumbar spine decreased rapidly after initiation of cART, in parallel to an increase in bone turnover. The greater bone loss in the ZDV/3TC/LPV/r group compared to the NVP/LPV/r group suggests that ZDV/3TC contributes to this process. The PTH increase does not explain this greater bone loss.

Greater decrease in bone mineral density with protease inhibitor regimens compared with nonnucleoside reverse transcriptase inhibitor regimens in HIV-1 infected naive patients

OBJECTIVE

To evaluate the change in bone mineral density (BMD) at specific sites in patients initiating antiretroviral therapy in a substudy of the ANRS 121 trial.

METHODS

Antiretroviral-naive patients were randomized (2: 1: 1) into three treatment strategy arms: a nonnucleoside reverse transcriptase inhibitor (NNRTI) and a boosted protease inhibitor (PI/r), a PI/r and two nucleoside reverse transcriptase inhibitors (NRTIs) or an NNRTI and NRTIs. Hip and lumbar spine standardized BMD were evaluated at baseline and week 48 by dual X-ray absorptiometry by a central reading laboratory.

RESULTS

Seventy-one patients were enrolled: 36 in the PI/r and NNRTI, 19 in the PI/r and NRTIs and 16 in the NNRTI and NRTIs arms. Baseline characteristics were [median (interquartile range)]: male (77%), age 40 years (33-49), 69% white, 58% smokers, BMI 23 kg/m2 (21-24), CD4 cell count 219 cells/microl (144-285). In the arms with NRTIs, 86% of patients received zidovudine/lamivudine. At baseline, 31% had osteopenia and 3% had osteoporosis. At week 48, there was a mean change in BMD of -4.1 +/- 3.9% at lumbar spine and -2.8 +/- 4.7% at hip (both P< or = 0.001). The decrease of BMD at lumbar spine was significantly worse in the PI/r and NNRTI arm (-4.4 +/- 3.4%) and in the PI/r and NRTIs arm (-5.8 +/- 4.5%) compared with the NNRTI and NRTIs arm (-1.5 +/- 2.9%), P = 0.007 and P = 0.001, respectively.

CONCLUSION

BMD was impaired in 34% of patients, before starting any antiretrovirals. After 1 year, the decrease in lumbar spine BMD was more pronounced in patients receiving either PI/r-containing regimen compared with NNRTI and NRTIs. BMD at specific sites should be monitored during lifelong antiretroviral therapy.

High frequency of vitamin D deficiency in ambulatory HIV-Positive patients

Several reports have suggested an increased prevalence of osteopenia and osteoporosis in HIV-infected individuals. Vitamin D deficiency may be a risk factor for osteoporosis and bone fractures. We aimed to determine the prevalence of vitamin D insufficiency in an outpatient HIV clinic in Boston. We collected serum levels of 25-OH vitamin D and evaluated calcium and vitamin D intake in adult HIV-positive outpatients during the winter and spring of 2005. Fifty-seven subjects were enrolled. The prevalence of moderate (< or = 20 and>10 ng/ml) and severe (< or =10 ng/ml) 25-OH vitamin D deficiency was 36.8% and 10.5%, respectively. Lower vitamin D intake was significantly associated with severe 25-OH vitamin D deficiency (p=0.01). Lactose intolerance tended to be associated with severe vitamin D deficiency (p=0.08). Antiretroviral use and low daily calcium intake were significantly associated with elevated parathyroid hormone levels (p=0.01 and 0.03, respectively). Vitamin D deficiency was frequent in ambulatory HIV-positive patients. HIV-infected individuals living in areas with low exposure to ultraviolet light during winter may benefit from vitamin D supplementation.

Evolution and predictors of change in total bone mineral density over time in HIV-infected men and women in the nutrition for healthy living study

BACKGROUND

Osteopenia is common in the era of effective antiretroviral therapy (ART), yet the etiology is unclear. We evaluated the association of host factors, disease severity, and ART to changes in total body bone mineral density (total BMD) over time in HIV-infected men (n = 283) and women (n = 96).

METHODS

Total BMD was measured annually by whole-body dual-energy absorptiometry (DXA), and medical, dietary, and behavioral history was collected. The median time from first to last DXA was 2.5 years (range 0.9-6.8 years). Using a repeated measures regression model, we identified variables independently associated with percent change in total BMD between consecutive DXA exams (n = 799 intervals), adjusted for age, race, sex, menopause, and smoking. We estimated percent change in total BMD over an average interval (1 year) standardized for representative levels of each determinant in males, premenopausal women, and postmenopausal women.

RESULTS

Median baseline age, CD4, and viral load were 42 years, 364 cells per cubic millimeter, and 2.7 log10 copies per milliliter, respectively. The estimated change in total BMD for those not on ART was -0.37% per year [95% confidence interval (CI) -0.76 to -0.02] for men, -0.08% per year (95% CI -0.49 to 0.33) for premenopausal women, and -1.07% per year (95% CI -1.86 to -0.28) for postmenopausal women. Greater loss of total BMD was associated with lower albumin, lower body mass index, prednisone/hydrocortisone use, tenofovir use, and longer duration of didanosine. Strength training and long duration of d4T and saquinavir prevented or mitigated bone loss. For those on ART for 3 years (not including the above agents), the rate of loss was -0.57% per year (95% CI -1.00 to -0.14) for men, -0.28% (95% CI -0.71 to 0.15) for premenopausal women, and -1.27% (95% CI -2.07 to -0.47) for postmenopausal women. Postmenopausal women had greater loss than premenopausal women and men.

CONCLUSIONS

Low body weight, low albumin, catabolic steroid use, and menopause may accelerate bone loss, and strength training may be protective. Tenofovir and didanosine may also have a deleterious effect on BMD.

Tenofovir: what have over 1 million years of patient experience taught us?

Several groundbreaking trials and over 1 million years of patient experience have established tenofovir as an important component of HIV treatment. Tenofovir has demonstrated potent antiviral efficacy, with a low risk of developing resistance when used as part of an effective combination regimen. It is generally well tolerated, with a low risk of lipoatrophy and a favourable effect on lipid profile compared with older nucleoside analogue agents such as stavudine or zidovudine. Clinical data suggest that switching from thymidine analogues to a tenofovir-containing regimen can benefit patients with lipid abnormalities or lipoatrophy. This article reviews the development of tenofovir, including pivotal studies that have influenced HIV clinical practice.

[Bone mineral loss in patients with human immunodeficiency virus infection]

Life expectancy and quality of life among patients infected with human immunodeficiency virus (HIV) has dramatically improved with the advent of highly active antiretroviral therapy. Nonetheless, with the transformation of HIV infection into a chronic disease, a series of long-term consequences have been observed, among them osteoporosis. The prevalence of this condition is increasing among individuals with HIV infection. Although an epidemic of fragility fractures has not been described in these patients, an increase in the incidence of such fractures is anticipated as the HIV population ages, and this will undoubtedly have an impact on their quality of life. The numerous factors that favor the development of osteoporosis in these patients are related to the infection, itself, and the treatment received.

The tangle of nuclear receptors that controls xenobiotic metabolism and transport: crosstalk and consequences

The expression of many genes involved in xenobiotic/drug metabolism and transport is regulated by at least three nuclear receptors or xenosensors: aryl hydrocarbon receptor (AhR), constitutive androstane receptor (CAR), and pregnane X receptor (PXR). These receptors establish crosstalk with other nuclear receptors or transcription factors controlling signaling pathways that regulate the homeostasis of bile acids, lipids, glucose, inflammation, vitamins, hormones, and others. These crosstalks are expected to modify profoundly our vision of xenobiotic/drug disposition and toxicity. They provide molecular mechanisms to explain how physiopathological stimuli affect xenobiotic/drug disposition, and how xenobiotics/drugs may affect physiological functions and generate toxic responses. In addition, the possibility that xenosensors may control other signaling pathways opens the way to new pharmacological opportunities.

Evolution of bone mineral density in AIDS patients on treatment with zidovudine/lamivudine plus abacavir or lopinavir/ritonavir

OBJECTIVES

The aim of the study was to determine the factors that may contribute to decreases in bone mineral density (BMD) in patients with AIDS.

METHODS

This was a prospective, non-randomized study. Dual X-ray absorptiometry (DXA) was used to determine the BMD of the lumbar spine, femoral neck and distal radius in treatment-naïve HIV-infected male patients with AIDS before and after 1 year of treatment with zidovudine (ZDV)/lamivudine (3TC) plus abacavir (ABC) or lopinavir/ritonavir (LPV/r).

RESULTS

Basal DXA was performed in 50 patients with CD4 counts <200 cells/microL and/or any AIDS-defining condition. Thirty-two patients completed 1 year with full adherence (17 on ABC and 15 on LPV/r) and a second DXA was then performed. At baseline, 19% had osteopenia at the lumbar spine and 19% at the femoral neck. Low body weight was related to low BMD. After 48 weeks, BMD loss was significant at the three locations. The percentage of BMD loss at the femoral neck tended to be greater in the lopinavir group (5.3 vs. 3.2%, P=0.058). The differences became significant at the lumbar spine (5.7 vs. 2.7%, P=0.044). In the multivariate analysis, the treatment with LPV/r remained associated with bone loss at the lumbar spine.

CONCLUSIONS

Osteopenia is frequent in treatment-naïve HIV-infected men with AIDS. Bone loss is higher with LPV/r-based regimens compared with triple nucleoside reverse transcriptase inhibitors.

CLINICAL Review # : low body weight mediates the relationship between HIV infection and low bone mineral density: a meta-analysis

CONTEXT

HIV infection has been associated with low bone mineral density (BMD) in many cross-sectional studies, although longitudinal studies have not demonstrated accelerated bone loss. The cross-sectional studies may have been confounded by the failure to control for low body weight in HIV-infected patients.

OBJECTIVE

Our objective was to determine whether low body weight might explain the association of HIV infection with low BMD.

DATA SOURCES

MEDLINE and EMBASE were searched for English language studies published from 1966 to March 2007, and conference abstracts prior to 2007 were hand-searched.

STUDY SELECTION

All studies reporting BMD and weight or body mass index in adult patients with HIV and a healthy age- and sex-comparable control group were included. Nine of 40 identified studies and one of 68 identified abstracts were eligible.

DATA SYNTHESIS

We adjusted for the between-groups weight differences using regression coefficients from published cohorts of healthy men and women. On average, HIV-infected patients were 5.1 kg [95% confidence interval (CI), -6.8, -3.4; P < 0.001] lighter than controls. At all skeletal sites, unadjusted BMD was lower by 4.4-7.0% in the HIV-infected groups than the controls (P < 0.01). After adjustment for body weight, residual between-groups differences in BMD were small (2.2-4.7%) [lumbar spine, -0.02 (95% CI, -0.05, 0.01) g/cm2; P = 0.12; total hip, -0.02 (95% CI, -0.04, 0.00) g/cm2; P = 0.031; femoral neck, -0.04 (95% CI, -0.07, -0.01) g/cm2; P = 0.013; and total body, -0.03 (95% CI, -0.07, 0.01) g/cm2, P = 0.11].

CONCLUSION

HIV-infected patients are lighter than controls and low body weight may largely account for the high prevalence of low BMD reported in HIV-infected patients. However, in the setting of current treatment practice, HIV infection per se is not a risk factor for low BMD.