Association Between 10-Year Fracture Probability and Nonalcoholic Fatty Liver Disease With or Without Sarcopenia in Korean Men: A Nationwide Population-Based Cross-Sectional Study

Effects of Metabolic Dysfunction-Associated Steatotic Liver Disease on Bone Density and Fragility Fractures: Associations and Mechanisms

Metabolic dysfunction-associated steatotic liver disease (MASLD) has profound adverse effects on bone health and homeostasis. MASLD appears to be associated with changes in bone mineral density (BMD) and fracture rate. However, the data are ambiguous and conflicting. Although several studies have shown that children and adolescents with MASLD have decreased BMD, the data on the prevalence of fragility fractures among children are scarce. In adults, increasing evidence suggests that MASLD decreases BMD and increases the risk of fragility fractures, which appears to be due to deterioration of bone architecture in addition to a decrease in BMD. Effects of MASLD on bone health may also be age- and race-specific. MASLD does not seem to increase fracture risk in children and adolescents but increases the risk of fractures in elderly men, especially those of Asian origin. From a mechanistic perspective, bone remodeling is a continuous process between osteoblasts (bone-forming) and osteoclasts (bone-resorbing), with any imbalance resulting in metabolic bone disease. In individuals with MASLD, loss of anabolic insulin receptor signaling (insulin resistance) in osteoblasts and increased receptor activator of nuclear factor κB (RANK)/RANK ligand signaling in osteoclasts (proinflammatory cytokines) swings the pendulum toward accelerated bone loss. These processes are further complicated by the concomitant presence of obesity, type 2 diabetes mellitus, or sarcopenia in individuals with MASLD. This study reviews the current literature associated with the effects of MASLD on BMD and fragility fractures in children/adolescents and adults. This review also discusses the pathomechanisms that link MASLD with changes in BMD and fragility fractures.

Anti-osteoporotic treatments in the era of non-alcoholic fatty liver disease: friend or foe

Over the last years non-alcoholic fatty liver disease (NAFLD) has grown into the most common chronic liver disease globally, affecting 17-38% of the general population and 50-75% of patients with obesity and/or type 2 diabetes mellitus (T2DM). NAFLD encompasses a spectrum of chronic liver diseases, ranging from simple steatosis (non-alcoholic fatty liver, NAFL) and non-alcoholic steatohepatitis (NASH; or metabolic dysfunction-associated steatohepatitis, MASH) to fibrosis and cirrhosis with liver failure or/and hepatocellular carcinoma. Due to its increasing prevalence and associated morbidity and mortality, the disease-related and broader socioeconomic burden of NAFLD is substantial. Of note, currently there is no globally approved pharmacotherapy for NAFLD. Similar to NAFLD, osteoporosis constitutes also a silent disease, until an osteoporotic fracture occurs, which poses a markedly significant disease and socioeconomic burden. Increasing emerging data have recently highlighted links between NAFLD and osteoporosis, linking the pathogenesis of NAFLD with the process of bone remodeling. However, clinical studies are still limited demonstrating this associative relationship, while more evidence is needed towards discovering potential causative links. Since these two chronic diseases frequently co-exist, there are data suggesting that anti-osteoporosis treatments may affect NAFLD progression by impacting on its pathogenetic mechanisms. In the present review, we present on overview of the current understanding of the liver-bone cross talk and summarize the experimental and clinical evidence correlating NAFLD and osteoporosis, focusing on the possible effects of anti-osteoporotic drugs on NAFLD.

Caring for the Bone Health Among Liver Transplant Recipients

Liver transplant outcomes have improved over the years, and currently, the quality of life and long-term well-being of these patients needs to be improved. Improving bone health goes a long way toward achieving this objective. Poor bone health (osteopenia and osteoporosis) although prevalent, is often overlooked owing to its asymptomatic nature. It can be complicated by debilitating fracture affecting quality of life. It is recommended to assess and optimize bone health prior to liver transplant. Multiple factors contribute to poor bone health in a liver transplant recipient and it is vital to understand and ameliorate these. A careful and targeted approach with inputs from multidisciplinary team involving transplant physician, endocrinologist, occupational therapist, nutritionist, and nursing personnel may often be required. In this review, we aim to concisely discuss the various aspects related to prevalence, pathophysiology, evaluation, treatment, and follow-up of bone disease among liver transplant recipients.

The associations of alcoholic liver disease and nonalcoholic fatty liver disease with bone mineral density and the mediation of serum 25-Hydroxyvitamin D: A bidirectional and two-step Mendelian randomization

BACKGROUND

Reduced bone mineral density (BMD) and osteoporosis are common in chronic liver diseases. However, the causal effect of alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) on BMD remains uncertain.

OBJECTIVES

This study uses a two-sample Mendelian randomization (MR) design to evaluate the genetically predicted effect of ALD and NAFLD on BMDs using summary data from publically available genome-wide association studies (GWASs).

METHODS

The GWAS summary statistics of ALD (1416 cases and 213,592 controls) and NAFLD (894 cases and 217,898 controls) were obtained from the FinnGen consortium. BMDs of four sites (total body, n = 56,284; femoral neck, n = 32,735; lumbar spine, n = 28,498; forearm, n = 8143) were from the GEnetic Factors for OSteoporosis Consortium. Data for alcohol consumption (n = 112,117) and smoking (n = 33,299) and serum 25-Hydroxyvitamin D (25-OHD) level (n = 417,580) were from UK-biobank. We first performed univariate MR analysis with the Inverse Variance Weighted (IVW) method as the primary analysis to investigate the genetically predicted effect of ALD or NAFLD on BMD. Then, multivariate MR and mediation analysis were performed to identify whether the effect was mediated by alcohol consumption, smoking, or serum 25-OHD level.

RESULTS

The MR results suggested a robust genetically predicted effect of ALD on reduced BMD in the femoral neck (FN-BMD) (IVW beta = -0.0288; 95% CI: -0.0488, -0.00871; P = 0.00494) but not the other three sites. Serum 25-OHD level exhibited a significant mediating effect on the association between ALD and reduced FN-BMD albeit the proportion of mediation was mild (2.21%). No significant effects of NAFLD, alcohol consumption, or smoking on BMD in four sites, or reverse effect of BMD on ALD or NAFLD were detected.

CONCLUSION

Our findings confirm the genetically predicted effect of ALD on reduced FN-BMD, and highlight the importance of periodic BMD and serum 25-OHD monitoring and vitamin D supplementation as needed in patients with ALD. Future research is required to validate our results and investigate the probable underlying mechanisms.

Nonalcoholic Fatty Liver Disease Is Associated With Decreased Bone Mineral Density in Adults: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate the effect of nonalcoholic fatty liver disease (NAFLD) on bone mineral density (BMD) and the risk of osteoporosis and osteoporotic fracture in adults. We searched PubMed, MEDLINE, Embase, CINAHL, Web of Science, Cochrane Library, and Scopus for observational studies published from inception to January 2023 that reported adjusted effect sizes of NAFLD on BMD, osteopenia/osteoporosis, and osteoporotic fracture. The data were synthesized using multilevel and random-effects models. A total of 19 studies were included; of these, nine (21,294 participants) evaluated the effect of NAFLD on BMD, six (133,319 participants) investigated the risk of osteoporosis, and five (227,901 participants) assessed the risk of osteoporotic fracture. This meta-analysis showed that NAFLD was associated with decreased BMD (mean difference -0.019 g/cm2 , 95% confidence interval [CI] -0.036 to -0.002, I2 = 93%) and increased risks of osteoporosis (adjusted risk ratio [RR] = 1.28, 95% CI 1.08 to 1.52, I2 = 84%) and osteoporotic fractures (adjusted RR = 1.17, 95% CI 1.00 to 1.37, I2 = 67%). Subgroup analyses revealed that NAFLD had a significantly detrimental effect on BMD in men and on the BMD of the femoral neck and total hip. Stratified analyses by ethnicity demonstrated that NAFLD was not associated with BMD, osteoporosis, or osteoporotic fracture in non-Asian populations. The publication bias of all included studies was low; however, there was considerable heterogeneity among the studies, warranting a careful interpretation of the findings. Overall, our results suggest that NAFLD is associated with decreased BMD and an increased risk of osteoporosis or osteoporotic fractures. Male sex and the BMD of the femoral neck and total hip may be potential risk factors for decreased BMD in adults with NAFLD. Additionally, ethnic disparities were observed between Asian and non-Asian populations regarding BMD and osteoporotic fractures. © 2023 American Society for Bone and Mineral Research (ASBMR).

Non-Alcoholic Fatty Liver Disease and Bone Tissue Metabolism: Current Findings and Future Perspectives

Non-alcoholic fatty liver disease (NAFLD) is reaching epidemic proportions worldwide. Moreover, the prevalence of this liver disease is expected to increase rapidly in the near future, aligning with the rise in obesity and the aging of the population. The pathogenesis of NAFLD is considered to be complex and to include the interaction between genetic, metabolic, inflammatory, and environmental factors. It is now well documented that NAFLD is linked to the other conditions common to insulin resistance, such as abnormal lipid levels, metabolic syndrome, and type 2 diabetes mellitus. Additionally, it is considered that the insulin resistance may be one of the main mechanisms determining the disturbances in both bone tissue metabolism and skeletal muscles quality and functions in patients with NAFLD. To date, the association between NAFLD and osteoporosis has been described in several studies, though it worth noting that most of them included postmenopausal women or elderly patients and originated from Asia. However, taking into account the health and economic burdens of NAFLD, and the increasing prevalence of obesity in children and adolescents worldwide, further investigation of the relationship between osteopenia, osteoporosis and sarcopenia in NAFLD, including in young and middle-aged patients, is of great importance. In addition, this will help to justify active screening and surveillance of osteopenia and osteoporosis in patients with NAFLD. In this review, we will discuss various pathophysiological mechanisms and possible biologically active molecules that may interplay between NAFLD and bone tissue metabolism.

Osteosarcopenia in NAFLD/MAFLD: An Underappreciated Clinical Problem in Chronic Liver Disease

Chronic liver disease (CLD), including non-alcoholic fatty liver disease (NAFLD) and its advanced form, non-alcoholic steatohepatitis (NASH), affects a significant portion of the population worldwide. NAFLD is characterised by fat accumulation in the liver, while NASH is associated with inflammation and liver damage. Osteosarcopenia, which combines muscle and bone mass loss, is an emerging clinical problem in chronic liver disease that is often underappreciated. The reductions in muscle and bone mass share several common pathophysiological pathways; insulin resistance and chronic systemic inflammation are the most crucial predisposing factors and are related to the presence and gravity of NAFLD and to the worsening of the outcome of liver disease. This article explores the relationship between osteosarcopenia and NAFLD/MAFLD, focusing on the diagnosis, prevention and treatment of this condition in patients with CLD.

Liver-bone crosstalk in non-alcoholic fatty liver disease: Clinical implications and underlying pathophysiology

Osteoporosis is a common complication of many types of chronic liver diseases (CLDs), such as cholestatic liver disease, viral hepatitis, and alcoholic liver disease. Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent metabolic liver disease, affecting almost one third of adults around the world, and is emerging as the dominant cause of CLDs. Liver serves as a hub for nutrient and energy metabolism in the body, and its crosstalk with other tissues, such as adipose tissue, heart, and brain, has been well recognized. However, much less is known about the crosstalk that occurs between the liver and bone. Moreover, the mechanisms by which CLDs increase the risk for osteoporosis remain unclear. This review summarizes the latest research on the liver-bone axis and discusses the relationship between NAFLD and osteoporosis. We cover key signaling molecules secreted by liver, such as insulin-like growth factor-1 (IGF-1), fibroblast growth factor 21 (FGF21), insulin-like growth factor binding protein 1 (IGFBP1), fetuin-A, tumor necrosis factor-alpha (TNF-α), and osteopontin (OPN), and their relevance to the homeostasis of bone metabolism. Finally, we consider the disordered liver metabolism that occurs in patients with NAFLD and how this disrupts signaling to the bone, thereby perturbing the balance between osteoclasts and osteoblasts and leading to osteoporosis or hepatic osteodystrophy (HOD).

Chinese patients with type 2 diabetes mellitus and nonalcoholic fatty liver disease have lower serum osteocalcin levels compared to individuals with type 2 diabetes mellitus and no liver disease: a single-center cross-sectional study

PURPOSE

Osteocalcin may benefit nonalcoholic fatty liver disease (NAFLD). The present study aimed to explore the levels of serum osteocalcin in NAFLD in patients with type 2 diabetes mellitus (T2DM).

METHODS

In total, 1026 inpatients diagnosed with T2DM were enrolled in the study. NAFLD was defined according to the working definition of the revised guidelines for the management of NAFLD published by the Chinese Liver Disease Association, and confirmed by abdominal ultrasonography.

RESULTS

The current study found a NAFLD prevalence of 54% in the T2DM population. Subjects with NAFLD had lower concentrations of osteocalcin (8.28-13.99 ng/mL vs. 8.80-16.25 ng/mL, P = 0.001) but similar vitamin D, parathyroid hormone, beta-C-terminal telopeptide of type I collagen and procollagen type 1 N-peptide levels. Osteocalcin levels (OR: 0.956; 95% CI 0.926-0.987) were significantly associated with NAFLD. When all significant clinical indicators were analyzed together, increased BMI (OR: 1.120; 95% CI 1.065-1.178), fasting C-peptide (OR: 1.270; 95% CI 1.089-1.481) and triglycerides (OR: 1.661; 95% CI 1.284-2.148) were associated with a greater risk of NAFLD, while older age (OR: 0.967; 95% CI 0.948-0.986) and high osteocalcin levels (OR: 0.935; 95% CI 0.902-0.969) were related with a decreased risk of NAFLD. For every additional unit of osteocalcin, the patients received 7% deduced odds of NAFLD.

CONCLUSION

Low osteocalcin levels were associated with an increased risk for NAFLD in patients with T2DM.

Relationship between prevalence and risk of osteoporosis or osteoporotic fracture with non-alcoholic fatty liver disease: A systematic review and meta-analysis

The aim of this study was to investigate the relationship between prevalence and risks of osteoporosis or osteoporotic fracture and NAFLD. Patients with NAFLD should be monitored regularly for bone mineral density and bone metabolism indicators to prevent osteoporosis or osteoporotic fractures.

OBJECTIVES

The aim of this meta-analysis was to investigate the relationship between prevalence and risks of osteoporosis or osteoporotic fracture and non-alcoholic fatty liver disease (NAFLD).

METHODS

Five databases, including PubMed, Web of Science, Embase, Scopus and Cochrane Library, were searched since the conception of these databases until December 2021. The cohort studies, cross-sectional analyses or case-control studies evaluating the relationship between osteoporosis or osteoporotic fracture and NAFLD were retrieved from these databases. Relevant data were extracted from the included studies, and a meta-analysis was performed.

RESULTS

A total of seven studies were included. The prevalence of osteoporosis or osteoporotic fractures was higher in the NAFLD group than in the non-NAFLD group [OR = 1.17, 95%CI(1.04,1.31)], while the prevalence of osteoporosis was higher in the NAFLD group than in the non-NAFLD group [OR = 1.46, 95%CI (1.21,1.77) and OR = 1.48, 95%CI (1.31,1.68), respectively] in men and women. The risk of osteoporosis or osteoporotic fractures was higher in the NAFLD group than in the non-NAFLD group [OR = 1.33,95%CI (1.24,1.44) and OR = 1.57,95%CI (1.08,2.29), respectively]. The risk of osteoporosis or osteoporotic fractures was higher in male and female NAFLD groups than that in the non-NAFLD group [OR = 1.29, 95%CI(1.14,1.47) and OR = 1.36, 95%CI (1.25,1.48), respectively]. After parameter adjustment, the risk of osteoporosis or osteoporotic fracture was higher in the male NAFLD group than in the non-NAFLD group [OR = 2.10, 95%CI(1.36,3.25)], while no significant difference was found among women [OR = 1.13, 95%CI (0.86,1.48)].

CONCLUSIONS

The prevalence and risk of osteoporosis or osteoporotic fractures were significantly associated with NAFLD in men and women.

TRIAL REGISTRATION

PROSPERO 2022 CRD42022304708.

Serum Insulin-Like Growth Factor 1 Levels, Facture Risk Assessment Tool Scores and Bone Disorders in Patients with Primary Biliary Cholangitis

Insulin-like growth factor 1 (IGF-1) plays an important role in bone growth and maintenance, and its decreased levels are associated with bone disorders. This study aimed to evaluate the association of serum IGF-1 levels with osteoporosis, prevalent fractures and fracture risk based on the Fracture Risk Assessment Tool (FRAX) in patients with primary biliary cholangitis (PBC). This study included 127 consecutive patients with PBC. Based on the baseline serum IGF-1 levels, the participants were classified into the low (L)-, intermediate (I)- and high (H)-IGF-1 groups. According to the FRAX score, high fracture risk was defined as a 10-year major osteoporotic fracture probability (FRAX-MOF) ≥ 20% or a 10-year hip fracture probability (FRAX-HF) ≥ 3%. The serum IGF-1 levels were positively correlated with bone mineral density, and were negatively correlated with the FRAX-MOF/FRAX-HF. The L-IGF-1 group had the highest prevalence of osteoporosis (58.1%), prevalent fracture (48.4%) and high fracture risk (71.0%). Meanwhile, the H-IGF-1 group had the lowest prevalence of osteoporosis (9.7%), prevalent fracture (12.9%) and high fracture risk (9.7%). The prevalence of these events increased stepwise with decreasing serum IGF-1 levels. The cutoff values of IGF-1 for predicting osteoporosis, prevalent fracture and high fracture risk were 61.5 ng/mL (sensitivity/specificity, 0.545/0.894), 69.5 ng/mL (0.633/0.784) and 61.5 ng/mL (0.512/0.929), respectively. Serum IGF-1 levels were associated with bone disorders and the FRAX-derived fracture risk, and may be a useful indicator for initiating therapeutic intervention to prevent the incidence of fracture in patients with PBC.

Clinical practice advice on lifestyle modification in the management of nonalcoholic fatty liver disease in Japan: an expert review

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver diseases worldwide, including in Japan. The Japanese Society of Gastroenterology (JSGE) and the Japanese Society of Hepatology (JSH) have established the Japanese NAFLD/NASH guidelines in 2014 and revised these guidelines in 2020. As described in these guidelines, weight reduction by diet and/or exercise therapy is important for the treatment of NAFLD patients. The I148M single nucleotide polymorphism (rs738409 C > G) of PNPLA3 (patatin-like phospholipase domain-containing 3 protein) is widely known to be associated with the occurrence and progression of NAFLD. In the Japanese, the ratio of PNPLA3 gene polymorphisms found is approximately 20%, which is higher than that found in Westerners. In addition, the ratio of lean NAFLD patients is also higher in Japan than in Western countries. Therefore, the method for lifestyle guidance for the NAFLD patients in Japan would be different from that for the people in Western countries. The problems in the treatment of NAFLD patients include alcohol consumption and sarcopenia. Therefore, guidelines that can help clinicians treat Japanese patients with NAFLD are needed. In this expert review, we summarize evidence-based interventions for lifestyle modification (diet, exercise, alcohol, and sarcopenia) for the treatment of patients with NAFLD, especially from Japan and Asian countries.