Non-alcoholic fatty liver disease is associated with decreased bone mineral density in upper Egyptian patients

Nonlinear Association Between Serum Uric Acid and Femoral Neck Bone Mineral Density in Male Patients with Metabolic Dysfunction-Associated Fatty Liver Disease

Purpose

To investigate the relationship between serum uric acid (SUA) levels and femoral neck bone mineral density (BMD) in patients with metabolic dysfunction-associated fatty liver disease (MAFLD).

Patients and Methods

This cross-sectional study included 597 adult inpatients with type 2 diabetes mellitus and ultrasonography-confirmed fatty liver disease. Participants were stratified into tertiles based on femoral neck BMD. Gender-stratified linear regression analyses were performed to assess the relationship between SUA and femoral neck BMD. Nonlinear associations were explored using generalized additive models and two-piece linear regression.

Results

No significant linear association was observed between SUA and femoral neck BMD in either gender (all P > 0.05). However, after adjusting for confounders, a nonlinear relationship was identified in male patients, with a threshold at 388 μmol/L. The effect sizes for SUA levels below and above this threshold were 0.001 (95% CI: 0.000 to 0.002, P = 0.008) and -0.000 (95% CI: -0.002 to 0.000, P = 0.117), respectively. No nonlinear relationship was observed in female patients.

Conclusion

In male MAFLD patients, SUA levels exhibit a nonlinear relationship with femoral neck BMD, with a positive association observed between 300 μmol/L and 388 μmol/L. This relationship was not observed in female patients, suggesting gender-specific effects of SUA on bone health in MAFLD.

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.