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JAIDS Journal of Acquired Immune Deficiency Syndromes:
doi: 10.1097/QAI.0b013e3182845d88
Clinical Science

Chronic Viral Hepatitis Is Associated With Low Bone Mineral Density in HIV-Infected Patients, ANRS CO 3 Aquitaine Cohort

Lawson-Ayayi, Sylvie PharmD, PhD*,†,‡; Cazanave, Charles MD, PhD‡,§; Kpozehouen, Alphonse PhD*,†; Barthe, Nicole PharmD; Mehsen, Nadia MD; Hessamfar, Mojgan MD, PhD*,†,‡,#; Dupon, Michel MD‡,§; Dabis, François MD, PhD*,†,‡; Neau, Didier MD, PhD‡,§; for the Groupe Epidémiologie Clinique du SIDA en Aquitaine (GECSA)

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Author Information

*INSERM Unité 897, Université Bordeaux Segalen, Bordeaux, France;

Institut de Santé Publique, Epidémiologie et Développement (ISPED), Université Bordeaux Segalen, Bordeaux, France;

COREVIH d’Aquitaine, Centre Hospitalier Universitaire (CHU) de Bordeaux, Bordeaux, France;

§Services des Maladies Infectieuses et Médecine Tropicale, Hôpital Pellegrin, CHU de Bordeaux, Bordeaux, France;

Service d’Imagerie Médicale, CHU de Bordeaux, Bordeaux, France;

Service de Rhumatologie, CHU de Bordeaux, Bordeaux, France; and

#Service de Médecine Interne et de Maladies Infectieuses, Hôpital Saint André, CHU de Bordeaux, Bordeaux, France.

**See the Appendix for details.

Correspondence to: Charles Cazanave, MD, PhD, Service des Maladies Infectieuses et Médecine Tropicale, Hôpital Pellegrin, Place Amélie Raba-Léon, Bordeaux Cedex 33076, France (e-mail: charles.cazanave@chu-bordeaux.fr).

The Aquitaine Cohort is supported by the Agence Nationale de Recherches sur le SIDA et les hépatites virales (ANRS), grant ANRS C03. This study was supported in part by a grant from the French Charity Ensemble contre le SIDA/SIDACTION (15th call for proposals) and Roche Pharmaceuticals.

The authors have no other funding or conflicts of interest to disclose.

Received June 12, 2012

Accepted December 20, 2012

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Abstract

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

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

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

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

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INTRODUCTION

The prognosis of HIV-infected patients treated with antiretroviral therapy (ART) has dramatically improved over the past 15 years, and HIV infection is now a chronic disease with life-long treatment plans. Concomitantly, many studies have reported long-term complications of HIV infection, ART or both, involving systemic organs, and metabolic bone mineral diseases. High prevalence rates of osteopenia and osteoporosis have thus been observed in HIV-infected people,1 and the prediction of low bone mineral density (BMD) requires careful investigation within this population. Mechanisms involving either HIV itself or ART exposure, particularly the use of protease inhibitors (PIs) have been suggested1–10: bone loss has been more frequently observed in HIV-infected patients than in negative controls, but the precise mechanisms by which ART affects BMD remain unclear. Antiretroviral drugs have also been exonerated.11

In the general population, osteoporosis occurs frequently among the elderly and especially among postmenopausal women.12 Cross-sectional surveys have suggested that osteoporosis was frequent among younger HIV-infected patients of both genders.13 Risk factors for HIV-associated BMD loss are not well established, and few studies have examined the role of chronic viral hepatitis. Nevertheless, osteoporosis is frequent in the course of liver diseases.14 The prevalence of osteoporosis, based on the World Health Organization diagnosis criteria,15 varies from 8 to 56% in surveys among patients with chronic liver disease,16,17 with numerous hypotheses about its determinants,18 but the exact mechanism whereby liver disease affects BMD remains to be elucidated. In addition, many studies conducted among cirrhotic patients have suggested reduced bone formation and increased bone loss, both related to low levels of insulin-like growth factors.14,19–21

Many studies reported a relationship between an increased risk of fracture and hepatitis coinfection22,23 supporting the hypothesis of an association between chronic viral hepatitis and low BMD in HIV-infected patients, and even a differential gender effect was found.24

We aimed to compare BMD in HIV-infected patients of both genders, with or without viral hepatitis, and investigated the relationship between BMD and cirrhosis as an indicator of an advanced stage of chronic liver disease.

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METHODS

Study Design and Population

Prevalence of osteopenia and osteoporosis has been previously studied through a cross-sectional study in HIV-infected patients consecutively enrolled in the ANRS CO3 Aquitaine Cohort between December 2004 and May 2005, but most of them were free of hepatitis B or C viruses (HBV or HCV) coinfection.13 We updated this study sample by further enrolling patients coinfected with HBV or HCV, and who presented between November 2008 and October 2009 at Bordeaux Hospital outpatient clinics. The protocol was approved by the research ethical committee, and all the patients provided informed consent to participate in the study.

Epidemiological, clinical, biological, and therapeutic variables were recorded through patients' medical records and interview of patients.

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Bone Mineral Density Measurements

BMD of the lumbar spine, femoral neck, and total body were measured using the same instrument, dual energy x-ray absorptiometry (DXA; Hologic, Bedford, CT). Scans were analyzed by the same technician. Results were compared with normative curves and expressed as T-score and Z-score. The World Health Organization diagnosis classification was used to categorize bone status as normal if the T-score was >−1, osteopenia if the T-score was between −1 and −2.5, and osteoporosis if the T-score was <−2.5. Furthermore, because bone abnormalities affected rather young HIV-infected patients,13 the Z-scores were used to compare patients' BMD with the average value for a person of the same age and gender. Thus, a Z-score <−2.0 was used to characterize HIV-infected patients having less bone mass than expected.

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Viral Hepatitis and Cirrhosis

Positive hepatitis B surface antigen for at least 6 months defined chronic HBV infection. Chronic HCV infection was confirmed by positive anti-HCV antibodies and HCV RNA. Cirrhosis was diagnosed based on a hierarchical algorithm used in ANRS coinfection studies25: liver biopsy results (F4 in the Metavir system) or if non available, the presence of indirect clinical signs of cirrhosis (ascites, esophageal varices with or without bleeding, hepatic encephalopathy). Otherwise, noninvasive methods were used: the FibroScan result (with an elasticity value >12.5 kPa)26 in priority and the result of FibroTest (F4 in the METAVIR system)27 in the absence of atazanavir- or indinavir-related hyperbilirubinemia.

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Statistical Analyses

Statistical analyses were carried out using SAS software (SAS Institute Inc, Cary, NC). Comparative analysis between groups was based on the Kruskal–Wallis test for median values and their interquartile ranges (IQR) if continuous data; χ2 test was used to analyze the differences in categorical data. Statistical significance was set with a P value <0.05.

Univariable regression (stepwise forward) was performed to identify variables predictive of osteopenia and osteoporosis. All variables with a P value <0.25 were included in a multivariable polytomial logistic regression model to examine the potential determinants of osteopenia or osteoporosis. Modeling was stratified by gender because BMD standards (scores and curves) differed among women and men.

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RESULTS

Patients' Characteristics

Four hundred eighty-six HIV-infected patients were consecutively enrolled in the initial survey, and 140 viral hepatitis coinfected patients were additionally recruited.

Additional coinfected patients were more likely to be older (43 versus 45 years, P = 5 × 10−4) and be contaminated by intravenous drug use route (42.6% versus 58.6%, P = 0.009) than the monoinfected ones. There were significant differences with the original sample in HIV infection duration (15.0 versus 17.9 years, P = 10−4), and osteoporosis prevalence (27.1% versus 41.4%, P = 0.014). Not surprisingly, coinfected patients newly recruited experienced longer antiretroviral drugs, especially PI, nucleoside reverse transcriptase inhibitor, and tenofovir drugs (3.0 versus 2.0 years, P = 0.027; 9.4 versus 7.8 years, P = 3.10−4; and 1.2 versus 0.0 year, P = 10−4, respectively). No significant differences were found in gender, postmenopausal status, AIDS stage, body mass index (BMI), HIV viroimmunological markers, and previous hepatitis C treatment.

Altogether, 626 patients were included in this study: Three hundred and fifty-seven had HIV alone, and 269 had also chronic viral hepatitis (208 with HCV, 45 with HBV, and 16 with both HBV and HCV). Characteristics of patients according to viral hepatitis infection status are shown in Table 1. The overall median age was 44 years (IQR: 39; 49 years), and 26.5% of patients were female, 31.3% being postmenopausal. HIV RNA was undetectable in 70.9% of patients and the median CD4 count was 506/μL (IQR: 346; 696/μL). Low BMI was more common, and the duration of HIV infection and ART exposure were longer in coinfected patients. Cirrhosis was diagnosed in 61 (22.7%) coinfected and in 2 only (0.6%) of the HIV monoinfected patients, both related to excessive alcohol consumption.

Table 1
Table 1
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Postmenopausal women were older than premenopausal ones (51.0 versus 40.0 years, P = 10−4), and they presented more frequently HIV RNA <500 copies per milliliter (98.1% versus 75.7%, P < 10−4). Other variables were significantly comparable among these 2 groups.

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Bone Mineral Density, Hepatitis, and Cirrhosis

Osteopenia was diagnosed in 320 patients (51.1%) without any difference according to hepatitis coinfection status and osteoporosis in 187 (29.9%; Table 1). Osteoporosis was present in 34.6% of coinfected patients, and 26.3% of HIV-infected patients without chronic viral hepatitis (P = 0.032). Osteoporosis seemed to be less frequently observed in coinfected patients without cirrhosis (69/208, 33.2%) than in cirrhotic ones (24/61, 39.3%; P = 0.054).

DXA measurements were compared for each anatomic site according with viral hepatitis and cirrhosis status (Table 2). Median BMD values were significantly different between the HIV monoinfected group and the patients coinfected with viral hepatitis when measured at the femoral neck but not at lumbar spine in both males and females. Using T-score and Z-score values, low BMD was predominant at the femoral neck but did not significantly differ by hepatitis coinfection and cirrhotic status.

Table 2
Table 2
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Determinants of Low BMD

Polytomial logistic regression investigated patients' determinants of osteopenia and osteoporosis, and the results are reported by gender in Tables 3 and 4. After adjustment, the final model showed that, for both male and female patients, levels of low BMD were significantly associated with older age and BMI <20 kg/m². Osteopenia and osteoporosis were also particularly frequent among men who had reported sex with men: 52.6% and 38.3%, respectively. The association between chronic viral hepatitis and osteoporosis was only present in women (OR = 19.0, P = 0.0474). Among both genders, the multivariable analysis failed to identify any association between cirrhosis and either osteopenia or osteoporosis. ART and exposure duration to each antiretroviral class were not predictive of low BMD (data not shown).

Table 3
Table 3
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Table 4
Table 4
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DISCUSSION

We documented high prevalence rates of osteoporosis, considering the average age of the HIV-infected patients recruited, but these are comparable with prevalence findings previously reported in our cohort 13 and by others.28 The frequency of osteoporosis was higher in HIV-infected patients with chronic viral hepatitis than among HIV monoinfected ones but did not differ according to cirrhotic status.

Older age and low BMI were associated with osteoporosis in both women and men. Low BMI is the only known modifiable risk factor of low BMD documented in this study as shown in a previous meta-analysis29; bone mass loss was also higher in men who have sex with men than in any other patients as previously reported.13

Most patients were clinically asymptomatic at the time of their DXA measurements and no marker of HIV disease progression was associated with osteopenia or osteoporosis in the multivariable model. Furthermore, neither infection duration nor advanced immunosuppression (CD4 count <200/μL) was associated with osteoporosis. Unlike some other reports,1,30 ART use was not found to be associated with reduced BMD in our analysis. We specifically investigated the nucleosidic and nucleotidic ART class, including lamivudine and tenofovir, as these specific drugs are known to be effective against HBV; but we could not identify any link.

The hypothesis of an epidemiological association between viral hepatitis and osteoporosis was the central aim of our study and was only confirmed in our HIV-infected female patients. Our results corroborate other findings published by Lo Re III et al24 who hypothesized that this association resulted from gender differences in the serum levels of hepatitis-associated cytokines, markers of bone resorption, or other factors that maintain bone balance [such as insulin-like growth factor-1 and osteoprotegerin (OPG)]. In healthy subjects, the increase in the serum receptor activator of nuclear factor kappa B ligand/OPG ratio leading to BMD loss was shown related to age, with gender differences.31 We previously identified in this cohort an association between decreased BMD and cardiovascular risk, which also supports common physiopathological mechanisms involving inflammatory factors.32 Our study was not designed to evaluate OPG and receptor activator of nuclear factor kappa B ligand levels.

Furthermore, our results do not match with published reports indicating an association between bone mass or mineral losses and liver fibrosis.33 Cirrhosis in HIV-infected patients with chronic viral hepatitis was not associated with BMD alteration in our series. The grading of cirrhosis severity we used did not detect a critical point of decline in liver disease progression as suggested in non HIV-infected populations.18,20,33

Our study had some limitations. The selection of coinfected patients occurred over 2 recruitment periods but was systematic in each period. Although we believed selection bias may exist, introduced by differences with the original coinfected patients, the cross-sectional study design did not allow a full causal assessment, but only independent association. Moreover, some potential confounders such as smoking, alcohol use, methadone use had not been collected at the time of the analysis, and the full multivariable model did not adjust on these variables.

Finally, the absence of markers of bone metabolism (such variables are not routinely measured) did not allow us to conclude about the underlying mechanisms of association between chronic viral hepatitis and osteoporosis in women.

In conclusion, our study strongly suggests that chronic viral hepatitis is associated with osteoporosis in HIV-infected women, but concludes that cirrhosis is not a condition significantly associated with osteoporosis in both genders. However, the contributive effects of cirrhosis and its consequences were not evaluated. Our findings have direct implications for clinical and therapeutical care of HIV-infected patients. For osteopenic or osteoporotic coinfected patients, preventive programs to reduce the BMD decline and the risk of fracture may be considered, while considering the specific needs of women, and should take into account the well-known risk factors (low BMI and older age). Attending physicians should encourage prevention and early treatment of bone loss to reduce fracture rate and ultimately improve patients' qualify of life.

Further longitudinal studies, are needed to elucidate the relationship between osteoporosis and chronic viral hepatitis, including inflammatory process accelerating bone mass loss.

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APPENDIX

The Groupe d'Epidémiologie Clinique du SIDA en Aquitaine (GECSA) coordinating the Aquitaine Cohort is organized as follows: Scientific committee: Prs F. Dabis (Principal Investigator), M. Dupon, P. Mercié, P. Morlat, JL. Pellegrin, and JM. Ragnaud. Epidemiology, Biostatistics: M. Bruyand, G. Chêne, F. Dabis, S. Lawson-Ayayi, R. Thiébaut. Infectious diseases, Internal Medicine: F. Bonnal, F. Bonnet, N. Bernard, O. Caubet, L. Caunègre, C. Cazanave, J. Ceccaldi, D. Chambon, I. Chossat, FA. Dauchy, C. De La Taille, S. De Witte, M. Dupon, A. Dupont, P. Duffau, H. Dutronc, S. Farbos, V. Gaborieau, MC. Gemain, Y. Gerard, C. Greib, M. Hessamfar, D. Lacoste, S. Lafarie-Castet, P. Lataste, E. Lazaro, D. Malvy, P. Mercié, E. Monlun, P. Morlat, D. Neau, A. Ochoa, JL. Pellegrin, JM. Ragnaud, MC. Receveur, S. Tchamgoué, MA. Vandenhende, JF. Viallard. Immunology: JF. Moreau, I. Pellegrin. Virology: H. Fleury, ME. Lafon, B. Masquelier, P. Trimoulet. Pharmacology: D. Breilh. Pharmacovigilance: G. Miremont-Salamé. Data collection: MJ. Blaizeau, M. Decoin, C. D’Ivernois, S. Delveaux, C. Hannapier, O. Leleux, B. Uwamaliya-Nziyumvira. Data management and Statistical analysis: S. Geffard, A. Kpozehouen, G. Palmer, D. Touchard.

Keywords:

HIV; viral hepatitis; cirrhosis; bone mineral density; osteoporosis

© 2013 Lippincott Williams & Wilkins, Inc.

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