Bone mineral density and disorders of mineral metabolism in chronic liver disease

Liver function linked to bone health: A bibliometric of the liver-bone axis

BACKGROUND

The liver exerts profound influence on skeletal health, while osseous tissues reciprocally modulate hepatic function. This bidirectional metabolic axis between these two organ systems plays a pivotal role in both physiological homeostasis and pathological states.

AIM

To investigate and analyze the literatures on liver-bone axis using bibliometrics.

METHODS

A comprehensive literature search pertaining to the liver-bone axis was conducted using the Science Citation Index Expanded within the Web of Science Core Collection. Subsequently, visualization and bibliometric analyses were performed utilizing VOSviewer (version 1.6.20), Citespace (version 6.2.R4), and the R programming language.

RESULTS

This comprehensive analysis encompasses 855 publications, comprising 694 articles and 161 reviews, authored by 4988 researchers from 425 institutions across 61 countries. The United States and China emerge as the leading nations in terms of publication volume. The University of California system stands out as the most influential institution in liver-bone axis research. Guanabens N is identified as the most prolific author in this field. The annual increase in publications related to the liver-bone axis underscores its growing prominence as a research focus. The study highlights key areas of investigation, including osteoporosis, bone metabolism, non-alcoholic fatty liver disease, and insulin-like growth factor-1, which represent both current and prospective hot topics within this domain.

CONCLUSION

This investigation employs bibliometric methodologies to conduct a systematic analysis of liver-bone axis literature spanning from 2001 to 2024. The exponential growth in publications over the past two decades underscores the significance of synthesizing research outcomes in this domain. Through rigorous statistical analyses, we delineate fundamental contributions to the field while providing strategic direction for emerging scholars. Furthermore, we illuminate current research trajectories and identify promising future investigative directions. Investigation of the liver-bone axis enhances our comprehension of inter-organ communication networks. Conceptualizing these organs as an integrated system provides profound insights into pathophysiological mechanisms and disease management strategies. This paradigm not only facilitates the development of sophisticated diagnostic modalities but also catalyzes the discovery of novel therapeutic agents targeting these mechanistic pathways, thereby advancing our capacity to diagnose and treat hepatic and skeletal disorders.

Environmental Cadmium Exposure Exacerbated Bone Loss in NAFLD Mice

Due to rapid urbanization and industrialization, Cadmium (Cd) contamination is widespread. Meanwhile, the prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing. Cd is linked to bone damage. However, the osteotoxicity of environmental Cd exposure in NAFLD remains unclear. Therefore, this study aimed to investigate the effects and potential mechanisms of Cd on bone metabolism in NAFLD mice. NAFLD mice were treated with 50 mg/L cadmium chloride in drinking water for 12 weeks. Bone microstructures were scanned by Micro-CT. Liver lipid droplets and fibrosis were measured by histopathological staining. Insulin tolerance tests were performed in mice. RT-PCR and Western blot were performed to analyse hepatic inflammation factors. Results show no damage in healthy mice exposed to Cd. However, Cd exacerbated liver fibrosis and significantly reduced cancellous bone mineral density and decreased the number and thickness of trabecular bone in NAFLD mice. Additionally, the morphology of trabecular bone transformed from a plate structure to a rod structure in NAFLD mice after Cd exposure. The underlying mechanism appears to be related to the Cd-induced direct or indirect toxicity. Exacerbated liver fibrosis, increased inflammatory factors (TGF-β and IL-1β), and reduced lecithin-cholesterol acyltransferase (LCAT) and insulin-like growth factor-1 (IGF-1) might contribute to bone damages. Collectively, our study illustrates that despite lower dosing Cd exposure did not induce bone damages in healthy mice, Cd caused bone loss in NAFLD mice. Therefore, it is recommended that individuals with metabolic disorders should avoid working in Cd pollution environment and consuming cadmium-contaminated food and water.

Fragility spinal fractures among cirrhotic liver transplant candidates in Croatia

INTRODUCTION

Existing data on fragility spinal fractures prevalence in liver transplant candidates are scarce and inconsistent. This may be due to other comorbidities, besides hepatic osteodystrophy (HO), that contribute to bone loss and fragility fracture prevalence in chronic liver disease (CLD).

OBJECTIVES

The aim of this study was to investigate the prevalence of spinal thoracic and lumbar fragility fractures among cirrhotic, non-chronic kidney disease (CKD), non-diabetic liver transplant candidates and to explore their relationship with clinical characteristics, laboratory markers and dual-energy x-ray absorptiometry (DXA) results.

MATERIAL AND METHODS

This cross-sectional observational study was conducted at Merkur University Hospital, Croatia, between February 2019 and May 2023. Adult patients with liver cirrhosis referred for liver transplantation were included. Patients with acute infection, CKD, diabetes mellitus, malignancies, inflammatory bone diseases and those on corticosteroid or antiresorptive therapy were excluded. Clinical, laboratory and radiological assessment was carried out and patients were accordingly allocated into non-fractured and fractured group for the purpose of statistical analysis.

RESULTS

A total of 90 patients were included in the study. There was 123 fractures, 87 (70.7 %) in the thoracic and 36 (29.3 %) in the lumbar region. Eighty-nine (72.4 %) fractures were grade 1, 31 (25.2 %) were grade 2 and 3 (2.4 %) were grade 3. Patients in the fractured group were significantly older (p < 0.001). No significant differences between fractured and non-fractured group according to laboratory and DXA parameters were noted. Subgroup with lumbar fractures had significantly lower bone mineral density values at L1-L4 region. Statistically significant negative correlation between bone specific alkaline phosphatase (BALP) and hip total BMD (rho = -0.414, p < 0.001) and spine total BMD (rho = -0.258, p = 0.014) values was found.

CONCLUSION

Present study confirmed detrimental impact of CLD and HO on bone strength. DXA measurement correlated with the presence of lumbar fragility fractures. A combination of standard X-ray imaging and DXA is needed for adequate bone evaluation in pretransplant period and BALP could be useful for detecting HO in CLD. Searching for other risk factors and implementing bone turnover markers and additional imaging techniques for bone loss evaluation in liver transplant candidates is needed.

Vitamin D status & bone health in patients with liver cirrhosis

Background & objectives

Vitamin D plays an important role in bone metabolism, and liver is the intermediary site of vitamin D metabolism. The purpose of this study was to study the prevalence of vitamin D deficiency and bone health in patients with cirrhosis.

Methods

Prospectively, serum 25-hydroxy vitamin D [25(OH)D] level were assessed in cirrhotics by chemiluminescence method. Endocrine Society Clinical practice guideline was used to define deficiency and insufficiency of vitamin D. Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry and the World Health Organization criteria was used to define osteoporosis and osteopenia. The lowest T score at the left hip neck or lumbar spine was taken as osteoporosis or osteopenia. The Child-Turcotte-Pugh score was used to assess the severity of cirrhosis.

Results

Cirrhotics (n=350, male: 278, compensated: 210) were included. Mean serum 25(OH)D level was 8.75 ng/ml. The prevalence of vitamin D deficiency (VDD) and low-BMD (osteopenia and osteoporosis) was 89.4 and 86 per cent, respectively. VDD, insufficiency and osteoporosis was found in 86.7, 11.9 and 33.8 per cent, respectively, in patients with compensated cirrhosis; and 93.6, 3.6 and 40 per cent, respectively, in patients with decompensated cirrhosis. Body mass index of >25 kg/m2 was protective for bone health.

Interpretation & conclusions

VDD and low-BMD is prevalent in Indian patients with cirrhosis and should be looked for in patients with cirrhosis for its prevention.

Bone loss in chronic liver diseases: Could healthy liver be a requirement for good bone health?

Given that the liver is involved in many metabolic mechanisms, it is not surprising that chronic liver disease (CLD) could have numerous complications. Secondary osteoporosis and increased bone fragility are frequently overlooked complications in CLD patients. Previous studies implied that up to one-third of these individuals meet diagnostic criteria for osteopenia or osteoporosis. Recent publications indicated that CLD-induced bone fragility depends on the etiology, duration, and stage of liver disease. Therefore, the increased fracture risk in CLD patients puts a severe socioeconomic burden on the health system and urgently requires more effective prevention, diagnosis, and treatment measures. The pathogenesis of CLD-induced bone loss is multifactorial and still insufficiently understood, especially considering the relative impact of increased bone resorption and reduced bone formation in these individuals. It is essential to note that inconsistent findings regarding bone mineral density measurement were previously reported in these individuals. Bone mineral density is widely used as the "golden standard" in the clinical assessment of bone fragility although it is not adequate to predict individual fracture risk. Therefore, microscale bone alterations (bone microstructure, mechanical properties, and cellular indices) were analyzed in CLD individuals. These studies further support the thesis that bone strength could be compromised in CLD individuals, implying that an individualized approach to fracture risk assessment and subsequent therapy is necessary for CLD patients. However, more well-designed studies are required to solve the bone fragility puzzle in CLD patients.

A Systematic Review and Meta-Analysis on Metabolic Bone Disease in Patients with Primary Sclerosing Cholangitis

Data about the association between primary sclerosing cholangitis (PSC) and metabolic bone disease are still unclear. PSC is a chronic cholestatic liver disease (CCLD) which affects the biliary tract, and it has a highly variable natural history. We systematically searched until 28 February 2022 MEDLINE, Cochrane Central Register of Controlled Trials, the ISI Web of Science, and SCOPUS, for studies in patients with PSC. We identified 343 references to potential studies. After screening them, we included eight studies (893 PSC patients, 398 primary biliary cirrhosis (PBC) patients, and 673 healthy controls) for the present meta-analysis. Pooled analyses found no difference in BMD-LS (Z = 0.02, p-value = 0.98) between PSC patients and healthy controls. BMD-LS was statistically lower in PBC patients than in PSC patients (Mean Difference, MD, 0.06, 95% CI 0.03 to 0.09, p-value = 0.0007). The lumbar spine T-score was higher in the PSC patients compared with PBC patients (MD 0.23, 95% CI 0.04 to 0.42, p-value = 0.02). Given the limited literature available, better designed, and larger scale primary studies will be required to confirm our conclusion.

Proximal Hip Geometry, Trabecular Bone Score, Bone Mineral Density and Bone Mineral Parameters in Patients With Cryptogenic and Hepatitis B Related Cirrhosis- A Study From the Indian Subcontinent

The impact of cryptogenic cirrhosis on skeleton has not been studied in Indian context. So this study investigated bone health in male patients with early cryptogenic cirrhosis as defined by Child-Turcot-Pugh A (CTP-A) categorization and compared it with patients diagnosed to have hepatitis B related chronic liver disease (CLD) on treatment and age, sex-matched healthy controls. It was a cross-sectional study, in which thirty male subjects were recruited in each group. Bone mineral density (BMD), trabecular bone score (TBS), hip structural analysis (HSA) and bone mineral parameters were assessed. The mean ±SD age of the study subjects was 39.3 ± 9.2 years. The mean 25-hydroxy vitamin D was significantly lower in subjects with cryptogenic cirrhosis as compared to controls (p = 0.001). Subjects with cryptogenic cirrhosis had significantly lower (1.297 ± 0.099) TBS as compared to hepatitis-B related CLD (1.350 ± 0.094) control subjects (1.351 ± 0.088) (p = 0.04). BMD at the hip and lumbar spine was also significantly lower in subjects with cryptogenic cirrhosis as compared to hepatitis-B related CLD and healthy age matched controls (p < 0.05). Most components of HSA were significantly affected in subjects with cryptogenic cirrhosis as compared to control subjects (p < 0.05). Patients with cryptogenic cirrhosis had significantly low TBS and BMD lumbar spine and hip as well as poor proximal hip geometry which may be good predictor of future fragility fractures.

Common musculoskeletal disorders in chronic liver disease patients

Chronic liver disease (CLD) is the commonest ailment affecting the hepatobiliary system. Six significant pathologies related to CLD include hepatic osteodystrophy (HO), increased infection susceptibility, sarcopenia, osteonecrosis of the femoral head (OFH), increased risk of periprosthetic complications and fracture. Hepatic osteodystrophy, which comprises osteopenia, osteoporosis, and osteomalacia, refers to alterations in bone mineral metabolism found in patients with CLD. The HO prevalence ranges from 13 to 95%. Low complement levels, poor opsonization capacity, portosystemic shunting, decreased albumin levels, and impaired reticuloendothelial system make the cirrhotic patients more susceptible to developing infectious diseases. Septic arthritis, osteomyelitis, prosthetic joint infection, and cellulitis were common types of CLD-associated infectious conditions. The incidence of septic arthritis is 1.5 to 2-fold higher in patients with cirrhosis. Sarcopenia, also known as muscle wasting, is one of the frequently overlooked manifestations of CLD. Sarcopenia has been shown to be independent predictor of longer mechanical ventilation, hospital stay, and 12-month mortality of post-transplantation. Alcohol and steroid abuse commonly associated with CLD are the two most important contributory factors for non-traumatic osteonecrosis. However, many studies have identified cirrhosis alone to be an independent cause of atraumatic osteonecrosis. The risk of developing OFH in cirrhosis patients increases by 2.4 folds and the need for total hip arthroplasty increases by 10 folds. Liver disease has been associated with worse outcomes and higher costs after arthroplasty. Cirrhosis is a risk factor for arthroplasty complications and is associated with a prolonged hospital stay, higher costs, readmission rates, and increased mortality after arthroplasty. Greater physician awareness of risk factors associated with musculoskeletal complications of CLD patients would yield earlier interventions, lower healthcare costs, and better overall clinical outcomes for this group of patients.

Influencing Factors and Molecular Pathogenesis of Sarcopenia and Osteosarcopenia in Chronic Liver Disease

The liver plays a pivotal role in nutrient/energy metabolism and storage, anabolic hormone regulation, ammonia detoxification, and cytokine production. Impaired liver function can cause malnutrition, hyperammonemia, and chronic inflammation, leading to an imbalance between muscle protein synthesis and proteolysis. Patients with chronic liver disease (CLD) have a high prevalence of sarcopenia, characterized by progressive loss of muscle mass and function, affecting health-related quality of life and prognosis. Recent reports have revealed that osteosarcopenia, defined as the concomitant occurrence of sarcopenia and osteoporosis, is also highly prevalent in patients with CLD. Since the differentiation and growth of muscles and bones are closely interrelated through mechanical and biochemical communication, sarcopenia and osteoporosis often progress concurrently and affect each other. Osteosarcopenia further exacerbates unfavorable health outcomes, such as vertebral fracture and frailty. Therefore, a comprehensive assessment of sarcopenia, osteoporosis, and osteosarcopenia, and an understanding of the pathogenic mechanisms involving the liver, bones, and muscles, are important for prevention and treatment. This review summarizes the molecular mechanisms of sarcopenia and osteosarcopenia elucidated to data in hopes of promoting advances in treating these musculoskeletal disorders in patients with CLD.

Review article: the role of nutrition in alcohol-associated liver disease

BACKGROUND

Malnutrition is a commonly encountered issue in patients with alcohol-associated liver disease. The role of nutritional supplementation in the management of alcohol-associated liver disease is integral to patient outcomes-it has been shown to decrease rates of hepatic encephalopathy, improve outcomes post-liver transplant, reduce 90-day hospital readmissions and lower mortality. Despite these benefits, many studies have shown nutritional support to be an underutilised tool in the care of patients with alcohol-associated liver disease.

AIMS

To review the epidemiology, pathophysiology, recommendations for nutritional assessment and supplementation, as well as future directions for research of the relationship between nutrition and alcohol-associated liver disease.

METHODS

A literature search was conducted via PubMed using MeSH terms to inform this narrative review.

RESULTS

Decreased dietary intake, socioeconomic status, impaired absorption of nutrients and increased free radical species are implicated in the pathophysiology of malnutrition in alcohol-associated liver disease.

CONCLUSIONS

Malnutrition is common in alcohol-associated liver disease, and physicians should be aware of its association with poor clinical outcomes. Routine nutritional assessment, involvement of a dietician and nutritional supplementation are recommended to improve clinical outcomes in patients with alcohol-associated liver disease.

Determining Bone Turnover Status in Patients With Chronic Liver Disease

Introduction Hepatic osteodystrophy is an osteoporotic bone disease that occurs in chronic liver disease patients. The global prevalence of osteoporosis in patients with chronic liver disease is 30% to 40%. The pathogenesis of hepatic bone disease is not clear, but it occurs due to unstable bone remodeling with increased bone resorption and decreases bone formation. There has been an interest in determining the clinical utility of bone turnover markers (BTMs) in the assessment of osteoporosis in chronic liver patients. Methods This was a cross-sectional study conducted in patients with chronic liver disease at the section of chemical pathology, department of pathology and laboratory medicine, Aga Khan University (AKU). A total of 50 patients with age >8 years and a history of liver disease >6 months were recruited from January to October 2019. Liver function tests, i.e. aspartate aminotransferase (AST), alanine transaminase (ALT), albumin, and bilirubin, along with clinical signs of liver disease chronicity, were noted. The samples for BTMs, i.e. total serum alkaline phosphatase (ALP) and serum C-terminal telopeptide of type-1 collagen (CTX) were withdrawn and analyzed on Microlab (ELItech Group, Puteaux, France) and ADVIA Centaur (Siemens Diagnostics, NY), respectively. Results The majority of patients were males (n=34, 68%). Twenty-four (48%) patients suffered from fibrosis while 26 (52%) were without fibrosis. Median platelet count (68×109/L (102.5-50)) and median cholesterol levels (102.5 mg/dl (147-99.5)) were decreased, whereas gamma-glutamyl transferase (GGT) levels were higher in the fibrosis group as compared to the non-fibrosis group. The median levels of total ALP were 91.5 IU/L (103-82), and the median levels of CTX were 0.24 pg/ml (0.34-0.21). Conclusion In the present study, no significant difference was found in the BTMs of patients with and without chronic liver disease (CLD). However, there was a positive and significant correlation of BTMs, particularly CTX with age, bilirubin levels, and hepatomegaly.

Macrophage-Stimulating Protein Enhances Osteoblastic Differentiation via the Recepteur d&apos;Origine Nantais Receptor and Extracellular Signal-Regulated Kinase Signaling Pathway

Background

Macrophage-stimulating protein (MSP; also known as macrophage stimulating 1 and hepatocyte growth factor-like protein) has been shown to play a crucial role in calcium homeostasis and skeletal mineralization in zebrafish. However, the precise role of MSP in osteoblasts has not been elucidated. In this study, we investigated the effect of MSP on osteoblast differentiation of pre-osteoblast cells.

Methods

Osteoblast differentiation upon MSP treatment was evaluated by analyzing the osteogenic gene expression, alkaline phosphatase (ALP) activity, and mineralized nodule formation. To assess changes in the MSP-RON signaling pathway, knockdown of Ron gene was performed using siRNA and pharmacological inhibitor treatment.

Results

Expression of the tyrosine kinase receptor RON, a receptor of MSP, was found to be significantly increased during osteoblast differentiation. MSP treatment significantly upregulated the expression of osteogenic marker genes and remarkably increased ALP activity and mineralized nodule formation. Conversely, knockdown of Ron significantly attenuated the expression of osteogenic marker genes and ALP activity that were induced upon MSP treatment. Mechanistically, MSP treatment significantly enhanced the phosphorylation of extracellular signal-regulated kinase (ERK); however, additional treatment with the selective ERK inhibitor PD98059 attenuated the effect of MSP on osteoblast differentiation.

Conclusions

Altogether, these results indicate that the MSP-RON axis is involved in promoting osteoblast differentiation via activation of the ERK signaling pathway.

Hepatic osteodystrophy in cirrhosis due to alcohol-related liver disease

INTRODUCTION

hepatic osteodystrophy, including osteoporosis, is an abnormal bone metabolism related with chronic liver diseases. Osteoporosis is associated with an increased risk of bone fractures, with a significant impact on morbidity, mortality and healthcare costs. Nevertheless, bone disorders tend to be undervalued in cirrhosis due to alcohol-related liver disease (ALD cirrhosis). This study aimed to assess the prevalence of hepatic osteodystrophy and osteoporosis in ALD cirrhosis.

METHODS

a prospective observational study was performed that included patients with ALD cirrhosis, between September 2017 and December 2018. Bone mineral density was determined by dual energy X-ray absorptiometry at the lumbar spine and the femoral neck. Hepatic osteodystrophy was defined as a T-score below -1 SD and osteoporosis as a T-score below -2.5 SD.

RESULTS

ninety-four patients were included; 24.5 % (n = 23) had prior fragility fractures and ten patients suffered new osteoporotic fractures during the study period. Hepatic osteodystrophy was diagnosed in 79.8 % (n = 75) and osteoporosis in 21.3 % (n = 20) of cases. Patients with hepatic osteodystrophy presented significantly worse Child-Turcotte-Pugh (p < 0.05) and Model for End-Stage Liver Disease (MELD-sodium) scores (p = 0.01). According to the multivariate analysis, lower body mass index (BMI) (OR = 0.787, 95 % CI: 0.688-0.901, p = 0.001) and vitamin D deficiency (OR = 6.798, 95 % CI: 1.775-26.038, p = 0.005) were significantly and independently associated with hepatic osteodystrophy. Patients with osteoporosis also had a lower BMI (p = 0.01). Female patients and those with prior fragility fractures were more likely to suffer from osteoporosis (p < 0.05).

CONCLUSION

our study revealed a high prevalence of hepatic osteodystrophy and osteoporosis in patients with ALD cirrhosis (particularly in those with a lower BMI) and a concerning high rate of fragility fractures. Bone mineral density should be assessed in order to allow for an early diagnosis and the implementation of preventive measures.

Association between osteoporosis and hepatitis B cirrhosis: a case-control study

Background and aims

Hepatitis B virus (HBV)-related cirrhosis is associated with decreased bone mineral density (BMD); however, the mechanism is yet unknown. To assess the incidence of osteoporosis in patients with HBV-associated cirrhosis and relevant mechanisms.

Methods

A total of 80 hospitalized patients with HBV-associated cirrhosis and 80 healthy controls were enrolled. The levels of serum osteocalcin, total procollagen type 1 amino-terminal propeptide, β-C-terminal telopeptide of type I collagen (β-CTX), and 25-hydroxy vitamin D3 (25(OH)D3) was evaluated in the cirrhosis group.

Results

The BMDs of the lumbar spine (P<0.001) and hip joints (P=0.015) in the cirrhosis group were significantly lower than those in the controls. The incidence of osteoporosis in the cirrhosis group was significantly higher than that in the control group (P<0.001). Compared to the patients of the Child-Pugh grade A and B, the BMD of lumbar spine and 25(OH)D3 was significantly decreased in patients of grade C, while β-CTX was elevated. Patients in the cirrhosis group faced a higher risk of osteoporosis as compared to the controls(P<0.001).

Conclusions

Enhanced bone resorption accounted for increased risk of osteoporosis in severe cirrhosis. Thus, HBV-associated cirrhosis was a risk factor for osteoporosis.

A critical assessment of the potential of pharmacological modulation of aldehyde dehydrogenases to treat the diseases of bone loss

Chronic alcoholism (CA) decreases bone mass and increases the risk of hip fracture. Alcohol and its main metabolite, acetaldehyde impairs osteoblastogenesis by increasing oxidative stress. Aldehyde dehydrogenase (ALDH) is the rate-limiting enzyme in clearing acetaldehyde from the body. The clinical relevance of ALDH in skeletal function has been established by the discovery of single nucleotide polymorphism, SNP (rs671) in the ALDH2 gene giving rise to an inactive form of the enzyme (ALDH2*2) that causes increased serum acetaldehyde and osteoporosis in the affected individuals. Subsequent mouse genetics studies have replicated human phenotype in mice and confirmed the non-redundant role of ALDH2 in bone homeostasis. The activity of ALDH2 is amenable to pharmacological modulation. ALDH2 inhibition by disulfiram (DSF) and activation by alda-1 cause reduction and induction of bone formation, respectively. DSF also inhibits peak bone mass accrual in growing rats. On the other hand, DSF showed an anti-osteoclastogenic effect and protected mice from alcohol-induced osteopenia by inhibiting ALDH1a1 in bone marrow monocytes. Besides DSF, there are several classes of ALDH inhibitors with disparate skeletal effects. Alda-1, the ALDH2 activator induced osteoblast differentiation by increasing bone morphogenic protein 2 (BMP2) expression via ALDH2 activation. Alda-1 also restored ovariectomy-induced bone loss. The scope of structure-activity based studies with ALDH2 and the alda-1-like molecule could lead to the discovery of novel osteoanabolic molecules. This review will critically discuss the molecular mechanism of the ethanol and its principal metabolite, acetaldehyde in the context of ALDH2 in bone cells, and skeletal homeostasis.

Hepatic osteodystrophy and fracture risk prediction using FRAX tool in Indian patients with cirrhosis

BACKGROUND AND AIM

The main clinical relevance of hepatic osteodystrophy is the increased risk of fractures. Dual-energy X ray absorptiometry (DEXA)-based assessment of bone mineral density, the current gold standard for diagnosing osteoporosis, is not the sole determinant of fracture risk. Other clinical risk factors also play an important role. This study was carried out to assess the prevalence and risk factors of hepatic osteodystrophy and estimate the entailed fracture risk by using the FRAX tool in a cohort of Indian cirrhotics.

METHODS

Consecutive patients with cirrhosis (n = 120) were recruited. Etiologic workup, liver function tests, serum calcium, phosphate, 25(OH)D, HbA1c, and DEXA scan were performed. Hepatic osteodystrophy was defined as a T score of < -1. FRAX scores were calculated using the Indian calculator.

RESULTS

The study cohort was predominantly male (86.7%) with a median age of 49 (40-65) years. Alcohol was the most common etiology (80%). All patients had Child-Turcotte-Pugh class B (63.3%) or class B (36.7%) cirrhosis. Hepatic osteodystrophy was present in 83.3% patients. On multivariate analysis, smoking (odds ratio [OR]: 3.1 [1.76-4.7], P < 0.001) and serum 25(OH)D (OR: 0.23 [0.09-0.94]; P = 0.03) showed significant association with hepatic osteodystrophy. The 10-year probability of major osteoporotic fracture and hip fracture was 5.7% (2.1-28.9) and 2.5% (1.4-7.4), respectively. Using a FRAX probability cut-off of 20% for major osteoporotic fracture and 3% for hip fracture, 30% patients qualified for osteoporosis treatment.

CONCLUSION

Hepatic osteodystrophy is widely prevalent among Indian patients with cirrhosis and entails a high risk of fractures. Approximately one-third of patients with cirrhosis need treatment to reduce the risk of osteoporotic fractures.

Relationship between Osteosarcopenia and Frailty in Patients with Chronic Liver Disease

Osteosarcopenia and frailty have a negative health impact on an aging society. This cross-sectional study aimed to investigate the clinical characteristics and relationship of osteosarcopenia and frailty in 291 patients with chronic liver disease (CLD), who comprised 137 males and 154 females, with a median age of 70.0 years. Sarcopenia was diagnosed according to the Japan Society of Hepatology criteria. Bone mineral density was measured using dual-energy X-ray absorptiometry. Frailty was defined by five parameters (exhaustion, slowness, weakness, low physical activity, and weight loss). Among the 291 patients, 49 (16.8%) and 81 (27.8%) had osteosarcopenia and frailty, respectively. Frailty and vertebral fracture were more frequently noted in patients with osteosarcopenia than in those without osteosarcopenia (79.6% vs. 17.4% and 59.2% vs. 20.2%, respectively; p < 0.001 for both). Meanwhile, osteosarcopenia and vertebral fracture were more frequently observed in patients with frailty than in those without frailty (48.1% vs. 4.8% and 49.4% vs. 18.1%, respectively; p < 0.001 for both). On multivariate analysis, frailty was an independent factor associated with osteosarcopenia (odds ratio (OR), 9.837; p < 0.001), and vice versa (OR, 10.069; p < 0.001). Osteosarcopenia and frailty were prevalent, closely interrelated, and increased the risk of vertebral fracture in patients with CLD.

Bone mineral density and trabecular bone score in treatment-naïve patients with non-cirrhotic hepatitis C virus infection

We studied 112 treatment-naïve chronic HCV patients without cirrhosis, and we found that, especially HCV+ postmenopausal women, they had lower TBS and BMD values than healthy controls. This suggests that HCV infection is an independent risk factor for osteoporosis, and therefore, screening for osteoporosis in postmenopausal HCV+ women should be considered.

PURPOSE

To know whether patients in earlier stages of chronic HCV infection are at increased risk of developing low bone mass and bone microarchitectural changes and whether there is an association between bone metabolism and the severity of the liver disease.

METHODS

We studied 112 treatment-naïve chronic HCV outpatients and 233 healthy age- and sex-matched controls. Bone mineral density (BMD) and trabecular bone score (TBS) were assessed by DXA. Serum 25(OH)D, PTH, P1NP, and CTX were determined by electrochemiluminescence.

RESULTS

TBS values were significantly lower in HCV patients than in controls, both considering the population as a whole (1.337 ± 0.119 vs. 1.377 ± 0.122; p < 0.005) and after stratifying by sex (1.347 ± 0.12 vs. 1.381 ± 0.13 in men and 1.314 ± 0.10 vs. 1.369 ± 0.11 in women). The difference remained significant (p < 0.0001 in all cases) after adjusting for confounders. BMD was also lower in HCV patients (lumbar spine, 0.935 ± 0.151 vs. 0.991 ± 0.143 g/cm², p 0.001; femoral neck, 0.764 ± 0.123 vs. 0.818 ± 0.123 g/cm², p 0.0001; total hip, 0.926 ± 0.148 vs. 0.963 ± 0.132 g/cm², p 0.02), although, after adjustment, differences kept a clear trend towards statistical significance in women at the lumbar spine and femoral neck. However, in men and at the total hip in women, differences were no longer significant. We find no relationship between these parameters and the severity of the disease. No significant difference was observed in PTH and 25OHD status after adjustment. Finally, serum P1NP, but not CTX, was higher in HCV patients.

CONCLUSIONS

Our findings suggest that HCV infection is an independent risk factor for osteoporosis, especially among postmenopausal women. Therefore, the appropriateness of screening for osteoporosis in postmenopausal HCV-positive women should be considered.

Comparative assessment of sarcopenia using the JSH, AWGS, and EWGSOP2 criteria and the relationship between sarcopenia, osteoporosis, and osteosarcopenia in patients with liver cirrhosis

BACKGROUND

Sarcopenia and osteoporosis reduce life quality and worsen prognosis in patients with liver cirrhosis (LC). When these two complications coexist, a diagnosis of osteosarcopenia is made. We aimed to investigate the actual situations of sarcopenia, osteoporosis, osteosarcopenia, and vertebral fracture, and to clarify the relationship among these events in patients with LC.

METHODS

We describe a cross-sectional study of 142 patients with LC. Sarcopenia was defined according to the Japan Society of Hepatology (JSH) criteria, Asian Working Group for Sarcopenia (AWGS) criteria, and European Working Group on Sarcopenia in Older People (EWGSOP2) criteria. The skeletal muscle mass index (SMI) and handgrip strength were assessed using bioelectrical impedance analysis and a digital grip strength dynamometer, respectively. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry, and vertebral fracture was evaluated using spinal lateral X-rays. The severity of LC was assessed using the Child-Pugh classification.

RESULTS

Among the 142 patients, the prevalence of sarcopenia was 33.8% (48/142) according to the JSH and AWGS criteria and 28.2% (40/142) according to the EWGSOP2 criteria. The number of patients with osteoporosis, osteosarcopenia, and vertebral fracture was 49 (34.5%), 31 (21.8%), and 41 (28.9%), respectively. Multivariate analysis revealed a close association between sarcopenia and osteoporosis. Osteoporosis was independently associated with sarcopenia [odds ratio (OR) = 3.923, P = 0.010]. Conversely, sarcopenia was independently associated with osteoporosis (OR = 5.722, P < 0.001). Vertebral fracture occurred most frequently in patients with osteosarcopenia (19/31; 61.3%) and least frequently in those without both sarcopenia and osteoporosis (12/76; 15.8%). The SMI and handgrip strength values were significantly correlated with the BMD of the lumbar spine (r = 0.55 and 0.51, respectively; P < 0.001 for both), femoral neck, (r = 0.67 and 0.62, respectively; P < 0.001 for both), and total hip (r = 0.67 and 0.61, respectively; P < 0.001 for both).

CONCLUSIONS

Sarcopenia, osteoporosis, osteosarcopenia, and vertebral fracture were highly prevalent and closely associated with one another in patients with LC. Specifically, patients with osteosarcopenia had the highest risk of vertebral fractures. Early diagnosis of these complications is essential for treatment intervention.

Hepatic Osteodystrophy-Molecular Mechanisms Proposed to Favor Its Development

Almost all patients with chronic liver diseases (CLD) show altered bone metabolism. Depending on the etiology, this manifests in a severe osteoporosis in up to 75% of the affected patients. Due to high prevalence, the generic term hepatic osteodystrophy (HOD) evolved, describing altered bone metabolism, decreased bone mineral density, and deterioration of bone structure in patients with CLD. Once developed, HOD is difficult to treat and increases the risk of fragility fractures. Existing fractures affect the quality of life and, more importantly, long-term prognosis of these patients, which presents with increased mortality. Thus, special care is required to support the healing process. However, for early diagnosis (reduce fracture risk) and development of adequate treatment strategies (support healing of existing fractures), it is essential to understand the underlying mechanisms that link disturbed liver function with this bone phenotype. In the present review, we summarize proposed molecular mechanisms favoring the development of HOD and compromising the healing of associated fractures, including alterations in vitamin D metabolism and action, disbalances in transforming growth factor beta (TGF-β) and bone morphogenetic protein (BMP) signaling with histone deacetylases (HDACs) as secondary regulators, as well as alterations in the receptor activator of nuclear factor kappa B ligand (RANKL)-osteoprotegerin (OPG) system mediated by sclerostin. Based on these mechanisms, we give an overview on the limitations of early diagnosis of HOD with established serum markers.

Erythrocytosis and fatigue fractures associated with hepatoblastoma in a 3-year-old gelding

Hepatoblastoma was diagnosed in a 3-year-old Thoroughbred gelding presented with forelimb lameness with bilateral fatigue fractures of the proximal third metacarpal bones. An abdominal mass was detected on ultrasound examination of the abdomen. Absolute erythrocytosis was diagnosed after clinical and haematological evaluation. The fractured metacarpal bones were surgically removed but complications after surgery were fatal. The liver mass was diagnosed as a hepatoblastoma based on histology and immunochemical staining. The combination of hepatoblastoma and fatigue fractures has not been described previously in horses. A potential link between the hepatic and orthopaedic pathologies is hypothesised.

Nutrition in Alcoholic Liver Disease: An Update

Malnutrition is a change in body composition owing to disordered nutrition associated with a decrease in function and poor clinical outcomes. Malnutrition can result from overnutrition, undernutrition and inflammatory activity. Patients with alcoholic liver disease are at increased risk for malnutrition. In this article, we discuss the different methods used to assess malnutrition, prevalence of malnutrition, potential mechanisms underlying malnutrition, and its treatments in patients with alcoholic liver disease.

Bone mineral density in osteoporotic patients with pyogenic vertebral osteomyelitis: effect of early versus late treatment for osteoporosis

Patients with pyogenic vertebral osteomyelitis (PVO) are at greater risk of bone loss. However, treatment guidelines for bone loss have been lacking. Early bisphosphonate treatment within 6 weeks after PVO diagnosis was significantly associated with superior outcome in femoral BMD at 2-year follow-up, compared to that with late treatment.

INTRODUCTION

Due to absence of concern and proper guidelines, management of bone loss or osteoporosis in PVO is often neglected or delayed. A retrospective cohort study was planned to investigate differences in bone mineral density (BMD) in PVO patients with osteoporosis according to the timing of osteoporosis treatment.

METHODS

The PVO cohort consisted of 192 patients with osteoporosis who visited our institution between January 2003 and March 2015 and received bisphosphonate treatment for osteoporosis. According to the interval between PVO diagnosis and initiation of bisphosphonate, the patients were divided into three groups: group A (within 6 weeks after PVO diagnosis), group B (between 6 weeks and 3 months after diagnosis), and group C (more than 3 months after PVO diagnosis).

RESULTS

The percent increase in total femoral BMD in group A was significantly larger than that in group B at 2-year follow-up (p = 0.036). Similarly, the percent increase in trochanteric (p = 0.008) and total femoral (p = 0009) BMD in group A was significantly larger than that in group C at 2-year follow-up. Even after multivariate adjustment, total femoral BMD changes were significantly associated with the treatment group. Group B (odds ratio = 2.824, p = 0.013) and group C (odds ratio = 3.591, p = 0.001) were more significantly associated with total femoral BMD decreases at 2-year follow-up compared with group A.

CONCLUSIONS

Early bisphosphonate treatment within 6 weeks after PVO diagnosis (group A) was significantly associated with superior outcome in femoral BMD at 2-year follow-up, compared to that with late treatment (groups B and C).

Association between sarcopenia and osteoporosis in chronic liver disease

AIM

Sarcopenia and osteoporosis are important complications in chronic liver disease (CLD). The aim of this study was to investigate the relationship between sarcopenia and osteoporosis in patients with CLD.

METHODS

We retrospectively investigated the relationship between sarcopenia and osteoporosis in 112 CLD patients (57 men and 55 women), including 40 cirrhotic patients (36%), by measuring the appendicular skeletal muscle mass index (ASMI) using bio-impedance analysis. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry.

RESULTS

The sarcopenia rate was 13% (14/112), and the osteoporosis and osteopenia rates were 17% (19/112) and 65% (73/112), respectively. The rate of osteoporosis was significant and high in patients with sarcopenia or cirrhosis. In linear regression analysis, sarcopenia was significantly associated with the BMD of the lumbar spine (coefficient = -0.149, P = 0.014) and the femur neck (coefficient = -0.110, P = 0.003). Cirrhosis was also significantly associated with low BMD of the lumbar spine (coefficient = -0.160, P < 0.001) and the femur neck (coefficient = -0.066, P = 0.015). In the logistic analysis, sarcopenia (odds ratio = 6.16, P = 0.039) and cirrhosis (odds ratio = 15.8, P = 0.002) were independent risk factors for osteoporosis. The ASMI cut-off values for osteoporosis were 7.33 kg/m² in men and 5.71 kg/m² in women.

CONCLUSIONS

Sarcopenia was closely associated with osteoporosis, and a low ASMI was a potential predictor of osteoporosis in CLD patients. Screening for BMD might be required to detect osteoporosis in cirrhotic patients.

Association of serum zinc with markers of liver injury in very heavy drinking alcohol-dependent patients

Zinc deficiency is a frequent complication of alcohol abuse for multiple reasons including poor intake, increased excretion, internal redistribution and altered transporters. Zinc deficiency has been postulated to play a role in the development/progression of alcoholic liver disease (ALD). This study aimed to relate serum zinc levels with alcohol intake, serum albumin concentration and markers of inflammation and liver injury. One hundred and eight male and female very heavy drinking (≥10 drinks/day) individuals without clinical evidence of ALD were grouped by serum zinc concentration: normal-zinc group (zinc level≥71 μg/dl) included 67 patients, and low-zinc group (zinc level<71 μg/dl) included 41 patients. Data were collected on demographics, drinking history in last 90 days (heavy drinking days, HDD90 and total drinks, TD90), lifetime drinking history (LTDH) and clinical/ laboratory assessments. Our data show that in a very well-characterized, chronically heavy-drinking population without clinical evidence of liver disease, about 40% of subjects had low serum zinc levels. Frequency of heavy drinking days (HDD90) was significantly higher in the low-zinc group. Total drinks in past 90 days, LTDH and HDD90 showed significant associations with low zinc levels. The group with the low serum zinc had a higher aspartate aminotransferase/alanine aminotransferase ratio (good marker of alcoholic liver disease). Those in the low-zinc group had the lower albumin levels, a marker of hepatic synthetic function, and the highest C-reactive protein level, a biomarker of inflammation.

Reduced Serum IGF-1 Associated With Hepatic Osteodystrophy Is a Main Determinant of Low Cortical but Not Trabecular Bone Mass

Hepatic osteodystrophy is multifactorial in its pathogenesis. Numerous studies have shown that impairments of the hepatic growth hormone/insulin-like growth factor-1 axis (GH/IGF-1) are common in patients with non-alcoholic fatty liver disease, chronic viral hepatitis, liver cirrhosis, and chronic cholestatic liver disease. Moreover, these conditions are also associated with low bone mineral density (BMD) and greater fracture risk, particularly in cortical bone sites. Hence, we addressed whether disruptions in the GH/IGF-1 axis were causally related to the low bone mass in states of chronic liver disease using a mouse model of liver-specific GH-receptor (GHR) gene deletion (Li-GHRKO). These mice exhibit chronic hepatic steatosis, local inflammation, and reduced BMD. We then employed a crossing strategy to restore liver production of IGF-1 via hepatic IGF-1 transgene (HIT). The resultant Li-GHRKO-HIT mouse model allowed us to dissect the roles of liver-derived IGF-1 in the pathogenesis of osteodystrophy during liver disease. We found that hepatic IGF-1 restored cortical bone acquisition, microarchitecture, and mechanical properties during growth in Li-GHRKO-HIT mice, which was maintained during aging. However, trabecular bone volume was not restored in the Li-GHRKO-HIT mice. We found increased bone resorption indices in vivo as well as increased basal reactive oxygen species and increased mitochondrial stress in osteoblast cultures from Li-GHRKO and the Li-GHRKO-HIT compared with control mice. Changes in systemic markers such as inflammatory cytokines, osteoprotegerin, osteopontin, parathyroid hormone, osteocalcin, or carboxy-terminal collagen cross-links could not fully account for the diminished trabecular bone in the Li-GHRKO-HIT mice. Thus, the reduced serum IGF-1 associated with hepatic osteodystrophy is a main determinant of low cortical but not trabecular bone mass. © 2017 American Society for Bone and Mineral Research.

Diagnosis and Management of Cirrhosis-Related Osteoporosis

Management of cirrhosis complications has greatly improved, increasing survival and quality of life of the patients. Despite that, some of these complications are still overlooked and scarcely treated, particularly those that are not related to the liver. This is the case of osteoporosis, the only cirrhosis complication that is not solved after liver transplantation, because bone loss often increases after immunosuppressant therapy. In this review, the definitions of bone conditions in cirrhotic patients are analyzed, focusing on the more common ones and on those that have the largest impact on this population. Risk factors, physiopathology, diagnosis, screening strategies, and treatment of osteoporosis in cirrhotic patients are discussed, presenting the more striking data on this issue. Therapies used for particular conditions, such as primary biliary cirrhosis and liver transplantation, are also presented.

Prevalence of hepatic osteodystrophy and vitamin D deficiency in cirrhosis

BACKGROUND

Hepatic osteodystrophy (HO) is a major complication of cirrhosis. However, the prevalence of HO in a general cirrhotic patient population is not well defined as previous studies were in single aetiology or pre-liver transplant patients.

AIMS

The aims of this study were to investigate the prevalence of HO and vitamin D deficiency in patients with cirrhosis of mixed aetiology and disease severity and to determine the risk factors for HO.

METHODS

This is a single-centre cross-sectional study of all patients newly diagnosed with cirrhosis between September 2009 and December 2012. All patients underwent bone mineral density assessment using dual energy X-ray absorptiometry within 3 months of diagnosis. Demographic and biochemical factors, severity of underlying liver disease, previous fragility fractures, smoking status and alcohol use were collected on diagnosis. Logistic regression analysis was used to assess risk factors for HO.

RESULTS

Among the 406 patients (67% males), the median (range) age was 56 years (21-85) and most (84%) were Childs-Pugh A or B with a median (range) model for end-stage liver disease score of 11 (5-40). Alcohol (41%) was the most common underlying aetiology. The prevalence of HO and vitamin D deficiency (≤50 nmol/L) was 56% and 54%, respectively, and previous fragility fractures had occurred in 3%. Increasing age (odds ratio (95% confidence interval): 1.49 per 10 years (1.02-2.18), P = 0.04), excessive alcohol intake (2.34 (1.03-5.32), P = 0.04) and lower body mass index (0.92 per kg/m2 (0.87-0.98), P = 0.009) were independent risk factors for HO.

CONCLUSION

There is a high prevalence of HO and vitamin D deficiency in patients with cirrhosis at presentation irrespective of disease severity or underlying aetiology.

Study of Hepatic Osteodystrophy in Patients with Chronic Liver Disease

INTRODUCTION

Chronic Liver Disease (CLD) is a major cause of morbidity and mortality worldwide. It involves haemodynamic and metabolic complications. Hepatic Osteodystrophy is a metabolic bone disease that may occur in individuals with chronic liver disease. It can significantly affect morbidity and quality of life of these patients. Fractures are also associated with an excess mortality. It has been an under recognized and inadequately studied complication among Indian population. An early diagnosis is essential to correct reversible risk factors which predispose to bone mass loss.

AIM

To assess the prevalence of metabolic bone disease and identify the risk factors associated with hepatic osteodystrophy in patients with cirrhosis.

MATERIALS AND METHODS

This was an observational, cross-sectional, hospital based study conducted at a medical college hospital. All patients more than 20-year-old, diagnosed with chronic liver disease/Cirrhosis were enrolled. They were subjected to haematological, biochemical investigations, evaluation of Vitamin D and other hormonal parameters. Bone Mineral Density (BMD) was estimated by Dual Energy X-ray Absorptiometry (DEXA).

RESULTS

A total of 72 patients with mean age 50.04±11.24 years were included in the study. Amongst causes of chronic liver disease were alcoholic liver disease 22 (30.6%), CLD due to hepatitis B 24 (33.3%) and chronic hepatitis C 26 (36.1%). Twenty one (29.2%) patients had normal BMD while 51 (70.8%) had a low BMD. Out of these 51 patients, 36 (70.6%) were diagnosed of osteopenia and 15 (29.4%) others were found to have osteoporosis. Vitamin D levels and severity of liver disease had correlation with low BMD.

CONCLUSION

Low BMD is highly prevalent in patients with chronic liver disease of variable aetiologies. We advocate more randomised and prospective studies to be conducted on homogeneous groups with chronic liver disease in its various stages. In view of numerous therapeutic options available both for liver disease and bone disease, it is prudent to characterize this condition in order to give these patients a better chance of survival with good quality of life.

Vitamin D Deficiency Promotes Liver Tumor Growth in Transforming Growth Factor-β/Smad3-Deficient Mice Through Wnt and Toll-like Receptor 7 Pathway Modulation

Disruption of the TGF-β pathway is associated with liver fibrosis and suppression of liver tumorigenesis, conditions associated with low Vitamin D (VD) levels. However, potential contributions of VD to liver tumor progression in the context of TGF-β signaling remain unexplored. Our analyses of VD deprivation (VDD) in in vivo models of liver tumor formation revealed striking three-fold increases in tumor burden in Smad3(+/-) mice, with a three-fold increase in TLR7 expression compared to controls. ChIP and transcriptional assays confirm Smad3 binding at two TLR7 promoter SBE sites. Molecular interactions between TGF-β pathway and VDD were validated clinically, where an absence of VD supplementation was associated with low TGF-β pathway member expression levels and β-catenin activation in fibrotic/cirrhotic human liver tissues. Subsequent supplementing VD led to restoration of TGF-β member expression with lower β-catenin levels. Bioinformatics analysis provides positive supportive correlation between somatic mutations for VD-related genes and the TGF-β pathway. We conclude that VDD promotes tumor growth in the context of Smad3 disruption, potentially through regulation of TLR7 expression and β-catenin activation. VD could therefore be a strong candidate for liver cancer prevention in the context of aberrant Smad3 signaling.

Crucial Role of Vitamin D in the Musculoskeletal System

Vitamin D is well known to exert multiple functions in bone biology, autoimmune diseases, cell growth, inflammation or neuromuscular and other immune functions. It is a fat-soluble vitamin present in many foods. It can be endogenously produced by ultraviolet rays from sunlight when the skin is exposed to initiate vitamin D synthesis. However, since vitamin D is biologically inert when obtained from sun exposure or diet, it must first be activated in human beings before functioning. The kidney and the liver play here a crucial role by hydroxylation of vitamin D to 25-hydroxyvitamin D in the liver and to 1,25-dihydroxyvitamin D in the kidney. In the past decades, it has been proven that vitamin D deficiency is involved in many diseases. Due to vitamin D's central role in the musculoskeletal system and consequently the strong negative impact on bone health in cases of vitamin D deficiency, our aim was to underline its importance in bone physiology by summarizing recent findings on the correlation of vitamin D status and rickets, osteomalacia, osteopenia, primary and secondary osteoporosis as well as sarcopenia and musculoskeletal pain. While these diseases all positively correlate with a vitamin D deficiency, there is a great controversy regarding the appropriate vitamin D supplementation as both positive and negative effects on bone mineral density, musculoskeletal pain and incidence of falls are reported.

Bone Mineral Density, Bone Turnover, and Systemic Inflammation in Non-cirrhotics with Chronic Hepatitis C

BACKGROUND

Whether chronic HCV, a disease characterized by systemic inflammation, impacts bone mineral density (BMD) independent of cirrhosis is unknown.

AIM

We aimed to evaluate the association between BMD, systemic inflammation, and markers of bone turnover in chronic HCV without cirrhosis.

METHODS

Non-cirrhotics, 40-60 years old, with chronic HCV underwent measurement of: (1) BMD by dual-energy X-ray absorptiometry scan and (2) serum markers of systemic inflammation and bone turnover. By Chi-squared or t test, we compared those with normal versus low BMD.

RESULTS

Of the 60 non-cirrhotics, 53 % were female and 53 % Caucasian. Mean (SD) age was 53.3 years (5.7), total bilirubin 0.7 mg/dL (0.3), creatinine 0.8 mg/dL (0.2), and body mass index 28.4 kg/m(2) (6.5). Low BMD was observed in 42 %: 30 % had osteopenia, 12 % had osteoporosis. Elevated tumor necrosis factor α, interleukin-6, and C-reactive protein levels were found in 26, 32, and 5 %, respectively, but did not differ by BMD group (p > 0.05). Patients with low BMD had higher serum phosphorus (4.1 vs. 3.5 mg/dL) and pro-peptide of type 1 collagen (P1NP; 73.1 vs. 47.5 ng/mL) [p < 0.05], but similar bone-specific alkaline phosphatase, serum C-telopeptide, and parathyroid hormone levels.

CONCLUSIONS

Low BMD is prevalent in 40- to 60-year-old non-cirrhotics with chronic HCV, but not associated with systemic inflammatory markers. Elevated P1NP levels may help to identify those at increased risk of bone complications in this population. Chronic HCV should be considered a risk factor for bone loss, prompting earlier BMD assessments in both men and women.

Prospective study of profile of hepatic osteodystrophy in patients with non-choleastatic liver cirrhosis and impact of bisphosphonate supplementation

BACKGROUND AND OBJECTIVES

Patients with liver cirrhosis are more prone to develop reduced bone mineral density (BMD), i.e. hepatic osteodystrophy (HOD). There are few data on the prevalence of HOD in the Indian population and its treatment. We aimed to determine the prevalence of HOD, factors associated with it and the impact of bisphosphonates on BMD in patients with liver cirrhosis.

PATIENTS AND METHODS

Consecutive patients with liver cirrhosis admitted at Sir Ganga Ram Hospital, New Delhi, between August 2012 and July 2013 were enrolled. Patients with chronic kidney disease, hyperparathyroidism and those on steroids were excluded. BMD was measured by dual-energy X-ray absorptiometry (DEXA) at the lumbar spine and femoral neck. Osteopenia and osteoporosis were defined according to WHO criteria. Ibandronic acid 150 mg per day orally for six months was given to patients with osteoporosis and DEXA scan repeated.

RESULTS

A total of 215 patients (males 179, 83%) with a mean age of 50.9 ± 11 years were enrolled in this study. Prevalence of HOD was found to be 66% (142/215). On multivariate analysis BMI, TLC, total serum bilirubin and transient elastography values were found to be independently associated with HOD. All the patients with osteoporosis (n = 47) were treated with ibandronic acid as per protocol. Treated patients had significant improvement in DEXA scans after six months as compared to baseline.

CONCLUSIONS

HOD was seen in two-thirds of patients with liver cirrhosis. Higher liver stiffness as determined by transient elastography is significantly associated with HOD. Severity scores of liver disease (CTP and MELD) and etiology of liver cirrhosis did not determine HOD. Ibandronic acid is a safe drug that showed significant improvement in BMD in patients with liver disease along with osteoporosis.

Twelve months of voluntary heavy alcohol consumption in male rhesus macaques suppresses intracortical bone remodeling

Chronic heavy alcohol consumption is a risk factor for cortical bone fractures in males. The increase in fracture risk may be due, in part, to reduced bone quality. Intracortical (osteonal) bone remodeling is the principle mechanism for maintaining cortical bone quality. However, it is not clear how alcohol abuse impacts intracortical bone remodeling. This study investigated the effects of long-duration heavy alcohol consumption on intracortical bone remodeling in a non-human primate model. Following a 4-month induction period, male rhesus macaques (Macaca mulatta, n=21) were allowed to voluntarily self-administer water or alcohol (4% ethanol w/v) for 22h/d, 7 d/wk for 12months. Control monkeys (n=13) received water and an isocaloric maltose-dextrin solution. Tetracycline hydrochloride was administered orally 17 and 3days prior to sacrifice for determination of active mineralization sites. Animals in the alcohol group consumed 2.7±0.2g alcohol/kg/d (mean±SE) during the 12months of self-administration, resulting in a mean daily blood alcohol concentration of 77±9mg/dl from samples taken at 7h after the start of a daily session. However, blood alcohol concentration varied widely from day to day, with peak levels exceeding 250mg/dl, modeling a binge-drinking pattern of alcohol consumption. The skeletal response to alcohol was determined by densitometry, microcomputed tomography and histomorphometry. Significant differences in tibial bone mineral content, bone mineral density, and cortical bone architecture (cross-sectional volume, cortical volume, marrow volume, cortical thickness, and polar moment of inertia) in the tibial diaphysis were not detected with treatment. However, cortical porosity was lower (1.8±0.5 % versus 0.6±0.1 %, p=0.021) and labeled osteon density was lower (0.41±0.2/mm(2)versus 0.04±0.01/mm(2), p<0.003) in alcohol-consuming monkeys compared to controls, indicating a reduced rate of intracortical bone remodeling. In concordance, plasma CTx was lower (2.5±0.3ng/ml versus 1.7±0.1ng/ml, p=0.028) in the alcohol group. These results suggest that chronic heavy alcohol consumption may negatively impact bone health, in part, by suppressing intracortical bone remodeling.

Vitamin D status and viral response to therapy in hepatitis C infected children

AIM: To study the frequency of vitamin D deficiency in patients with hepatitis C virus (HCV) infection and to evaluate the role of vitamin D supplementation in improving antiviral therapy.

METHODS: Sixty-six children aged from 7-14 years (mean ± SD, 11.17 ± 2.293) diagnosed with HCV infection were matched to 28 healthy controls. Serum levels of 25 (OH) D3, calcium, phosphorus, alkaline phosphatase and plasma level of parathormone were measured. Quantitative PCR for HCV was performed Bone density was determined by dual energy X-ray absorptiometry. All cases received conventional therapy, and only 33 patients received vitamin D supplementation.

RESULTS: Children with HCV showed significantly increased levels of HCV RNA (P < 0.001), parathormone (P < 0.01) and decreased vitamin D levels (P < 0.05) (33.3% deficient and 43.3% insufficient) compared with controls. Abnormal bone status (Z score -1.98 ± 0.75) was found in ribs, L-spine, pelvis and total body. Cases treated with vitamin D showed significant higher early (P < 0.04) and sustained (P < 0.05) virological response. There was a high frequency of vitamin D deficiency among the Egyptian HCV children, with significant decrease in bone density. The vitamin D level should be assessed before the start of antiviral treatment with the correction of any detected deficiency.

CONCLUSION: Adding vitamin D to conventional Peg/RBV therapy significantly improved the virological response and helped to prevent the risk of emerging bone fragility.

Evidence of degraded BMD and geometry at the proximal femora in male patients with alcoholic liver cirrhosis

We examined the association of alcoholic cirrhosis in 33 patients with areal bone mineral density (BMD) and the assessed bone geometric strength of their proximal femora. Lower areal BMD, cross-sectional area and section modulus, thinner cortex, and higher buckling ratio suggest that the alcoholic liver cirrhosis is associated with lower measures of bone strength.

INTRODUCTION

Hepatic bone disease is an important complication of chronic liver disease and is associated with significant morbidity through fractures resulting in pain, deformity, and immobility. In this study, we examined the association of alcoholic cirrhosis and liver insufficiency stage with areal bone mineral density (aBMD) and additionally employed hip structure analysis (HSA) as an advanced method to assess bone geometric strength of the proximal femur in men with alcoholic liver cirrhosis.

METHODS

The study included 33 male patients with alcoholic liver cirrhosis and a control group of 36 healthy patients. Laboratory testing included the following biochemical markers of bone turnover: serum levels of osteocalcin and C-telopeptide of type 1 collagen. Areal BMD was measured by dual x-ray absorptiometry on the proximal femora. Structural parameters were then derived from these scans using hip structure analysis software.

RESULTS

After adjusting for age, body height, and weight, we found lower cross-sectional area (p = 0.005) and section modulus (p = 0.005), thinner cortex (p = 0.012), and higher buckling ratio (p = 0.043) in the neck region among patients with cirrhosis. The findings suggest that alcoholic liver cirrhosis is associated with lower measures of bone strength. These findings were consistent with decreased osteocalcin values and increased C-telopeptide of type 1 collagen in patients with cirrhosis, indicating reduction in bone formation and increased bone resorption.

CONCLUSION

Our results emphasize that HSA-derived structural indices of proximal femoral structure may be an important index of greater fragility in patients with alcoholic cirrhosis.

Areal bone mineral density in pediatric patients with chronic hepatitis B or chronic hepatitis C

Decreased bone mineral density (BMD) is a known complication of chronic liver disease in adults. Data on bone mass, an important factor for the development of osteoporosis in adult life, in young patients with chronic hepatitis B (HBV) and C virus (HCV) infections are scarce. We measured BMD at the lumbar spine and whole skeleton by dual-energy X-ray absorptiometry in 11 HBV- and 21 HCV-vertically infected untreated youths (3.9-21.1 years). BMD measurements were compared to those of 202 healthy subjects (3.0-21.9 years). The median BMD Z-score of the lumbar spine of HBV-infected patients was -0.3, ranging from -1.6 to 0.6, while the median whole skeleton BMD Z-score was 0.1 (-0.8 to 0.6). HBV-infected patients showed a median Z-score of the lumbar spine of 0.6 (-1.6 to 1.9), and a median whole skeleton BMD Z-score of 0.6, ranging from -1.5 to 1.4. Multivariate analyses have been performed to correct for differences in sex, age, and anthropometric measurements. Lumbar spine BMD values of HBV and HCV-infected patients were not significantly different from those of controls. Similarly, no differences were found between groups in total body BMD measurements. Our data suggest that, unlikely adult patients, untreated young patients with chronic HBV and HCV infection may not have impaired bone mass measurements.

Hepatic osteodystrophy

Metabolic disturbances of bone are frequent in patients with chronic liver disease. The prevalence of osteoporosis among patients with advanced chronic liver disease is reported between 12% and 55%; it is higher in primary biliary cirrhosis. All patients with advanced liver disease should be screened for osteoporosis with a densitometry, especially if the etiology is cholestatic and in the presence of other risk factors. Clinical relevance of hepatic osteodystrophy increases after liver transplantation. After liver transplant, a rapid loss of bone mineral density can be detected in the first 6 months, followed by stabilization and slight improvement of the values. At the time of transplantation, bone density values are very important prognostic factors. Therapy of hepatic osteodystrophy is based primarily on the control of risk factors: cessation of tobacco and alcohol assumption, reduction of caffeine ingestion, exercise, supplementation of calcium and vitamin D, limitation of drugs such as loop diuretics, corticosteroids, cholestyramine. Bisphosphonates have been proposed for the therapy of osteoporosis in patients with liver disease, particularly after liver transplantation. The possible side effects of oral administration of bisphosphonates, such as the occurrence of esophageal ulcerations, are of particular concern in patients with liver cirrhosis and portal hypertension, due to the risk of gastrointestinal hemorrhage from ruptured esophageal varices, although this risk is probably overestimated.

Prevalence of vitamin D deficiency and insufficiency in Bulgarian patients with chronic hepatitis C viral infection

AIMS

The present pilot study aimed to determine vitamin D status in Bulgarian patients with chronic HCV infection in respect to the severity of liver disease and response to interferon-ribavirin therapy.

METHODS

The study encompassed 296 patients: 161 males (54.4%) aged 42.08 ± 14.87 years, 135 females (45.6%) aged 45.72 ± 14.34 years, 86.5% of them infected with HCV genotype 1. Total 25-hydroxyvitamin-D (25OHD) was determined by liquid chromatography/tandem-mass spectrometric detection.

RESULTS

The median 25OHD level of the studied cohort was 50.40 nmol/L (range: 29.6-71.05). 25OHD deficient (< 25 nmol/L) were 16% of patients, 33% showed profound insufficiency (25-50 nmol/L), another 33% were in the range 50-80 nmol/L (mild insufficiency), the rest 18% were 25OHD sufficient. Significantly lower 25OHD levels were registered in cases with advanced fibrosis compared to those with mild or absent fibrosis (37.10 nmol/L vs. 53.00 nmol/L, respectively, p < 0.05). This association remained unchanged by seasonal variations in 25OHD levels. Inverse relationship was found between 25OHD and HCV-RNA (p < 0.01). Patients with sustained virological response to therapy had significantly higher 25OHD levels, compared to patients who failed to achieve viral eradication (56.90 nmol/L vs. 45.00 nmol/L, p = 0.012).

CONCLUSION

More than 80% of HCV-infected patients were vitamin D-deficient and -insufficient. The inverse relationship between 25OHD levels and viral load, liver fibrosis and treatment outcomes supports the hypothesis that improvement of vitamin D status may have considerable potential to amend the host defense against HCV infection and response to therapy.

Chronic CCl4 intoxication causes liver and bone damage similar to the human pathology of hepatic osteodystrophy: a mouse model to analyse the liver-bone axis

Patients with chronic liver diseases frequently exhibit decreased bone mineral densities (BMD), which is defined as hepatic osteodystrophy (HOD). HOD is a multifactorial disease whose regulatory mechanisms are barely understood. Thus, an early diagnosis and therapy is hardly possible. Therefore, the aim of our study consisted in characterizing a mouse model reflecting the human pathomechanism. Serum samples were collected from patients with chronic liver diseases and 12-week old C57Bl6/N mice after 6-week treatment with carbon tetrachloride (CCl4). Repetitive injections of CCl4 induced liver damage in mice, resembling liver fibrosis in patients, as assessed by serum analysis and histological staining. Although CCl4 did not affect primary osteoblast cultures, μCT analysis revealed significantly decreased BMD, bone volume, trabecular number and thickness in CCl4-treated mice. In both HOD patients and CCl4-treated mice, an altered vitamin D metabolism with decreased CYP27A1, CYP2R1, vitamin D-binding protein GC and increased 7-dehydrocholesterol reductase hepatic gene expression, results in decreased 25-OH vitamin D serum levels. Moreover, both groups exhibit excessively high active transforming growth factor-beta (TGF-β) serum levels, inhibiting osteoblast function in vitro. Summarizing, our mouse model presents possible mediators of HOD, e.g. altered vitamin D metabolism and increased active TGF-β. Liver damage and significant changes in bone structure and mineralization are already visible by μCT analysis after 6 weeks of CCl4 treatment. This fast response and easy transferability makes it an ideal model to investigate specific gene functions in HOD.

Alcohol and bone

Alcohol is widely consumed across the world in different cultural and social settings. Types of alcohol consumption differ between (a) light, only occasional consumption, (b) heavy chronic alcohol consumption, and (c) binge drinking as seen as a new pattern of alcohol consumption among teenagers and young adults. Heavy alcohol consumption is detrimental to many organs and tissues, including bones. Osteoporosis is regularly mentioned as a secondary consequence of alcoholism, and chronic alcohol abuse is established as an independent risk factor for osteoporosis. The review will present the different mechanisms and effects of alcohol intake on bone mass, bone metabolism, and bone strength, including alcoholism-related "life-style factors" such as malnutrition, lack of exercise, and hormonal changes as additional causative factors, which also contribute to the development of osteoporosis due to alcohol abuse.

Increased bone mineral density in patients with non-alcoholic steatohepatitis

AIM: To determine the relationship between non-alcoholic steatohepatitis (NASH) and bone mineral density (BMD).

METHODS: A total of 38 patients (25 males) with a diagnosis of histologically proven NASH and 42 healthy controls (24 males) were enrolled in the study. Demographic features, clinical findings, complete blood count and routine biochemical analysis, as well as adrenal, thyroid and gonadal functions, were recorded. Additionally, intact parathormone, 25-OH-vitamin-D3, tumor necrosis factor-α, interleukin-6, interleukin-1, insulin-like growth factor-1 and insulin-like growth factor binding protein-3 levels were measured in both groups. Furthermore, lumbar spine and femoral neck BMD of both groups were measured by the dual-energy X-ray absorptiometry (DXA) method.

RESULTS: The mean age was 41 ± 12 years in the NASH group and 43 ± 11 years in the control group. Among demographic features, waist circumference was significantly larger in the NASH group compared to the control group (P < 0.019). Among laboratory parameters, serum triglyceride (P < 0.008), alanine transaminase (P < 0.0001), aspartate transaminase (P < 0.001), alkaline phosphatase (P < 0.016), gamma glutamyl transferase (P < 0.0001), ferritin (P < 0.001) and 25-OH-vitamin-D3 levels (P < 0.0001) were significantly higher in the NASH group compared to the control group. Lumbar BMD was significantly higher in the NASH group compared to the control group (1.057 ± 0.119 g/cm²vs 0.941 ± 0.133 g/cm²; P < 0.001, respectively). In the NASH group, there was no significant relationship between BMD and fibrosis stage in liver biopsy.

CONCLUSION: NASH increases BMD and may be related to an elevated serum 25-OH-vitamin D3 level.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Decline in serum 25 hydroxyvitamin D levels in HIV-HBV-coinfected patients after long-term antiretroviral therapy

BACKGROUND

Vitamin D insufficiency plays an important role in the development of fibrosis in chronic liver disease.

METHODS

This was a cross-sectional study from Thailand. Liver fibrosis was assessed by transient elastography. Serum 25 hydroxyvitamin D (25[OH]D)<30 ng/ml was defined as hypovitaminosis D. 25(OH)D was assessed prior to and following tenofovir disoproxil fumarate (TDF). Factors related to 25(OH)D levels were determined by logistic regression analysis.

RESULTS

A total of 158 HIV-HBV-coinfected patients (32% female, median age 43 years) were included. Overall, liver disease was mild with 13.4% having a fibrosis score (FS) of 7.1-14 kPa and 2% with a FS>14 kPa. Median (IQR) duration on TDF was 5 years (4-7). The median estimated glomerular filtration rate was 96.9 ml/min/1.73 m(2). The median (IQR) serum 25(OH)D levels prior to and following TDF were 24.8 ng/ml (21.3-30.6) and 22.8 ng/ml (18.0-27.7), respectively; P≤0.001). The proportion of patients with hypovitaminosis D significantly increased from 72.2% (95% CI 64.7, 78.6) prior to TDF to 84.2% (95% CI 77.7, 89.0) after taking TDF (P=0.01). Factors associated with hypovitaminosis D by multivariate analysis were female sex (adjusted OR 3.8, 95% CI 1.1, 13.7; P=0.038) and duration of antiretroviral therapy (ART)>5 years (OR 3.3, 95% CI 1.2, 8.8; P=0.017). Vitamin D levels were not associated with significant liver fibrosis.

CONCLUSIONS

Although our HIV-HBV-coinfected patients live in the tropics, there was a high prevalence of hypovitaminosis D, especially in female patients and those receiving prolonged ART. Since HIV-HBV-coinfection requires long-term use of the HBV-active drug, TDF, which can also contribute to bone loss, routine vitamin D assessment and supplementation as necessary should be considered.