Impact of alcohol consumption and muscle mass on bone mineral density in metabolic dysfunction and alcohol-associated liver disease (MetALD) and metabolic dysfunction-associated steatotic liver disease (MASLD)

Metabolic dysfunction and alcohol-associated liver disease (MetALD) and metabolic dysfunction-associated steatotic liver disease (MASLD) are newly defined conditions within steatotic liver disease (SLD). We have previously reported that lean physique, hypertriglyceridemia and weak grip strength are risk factors for decreased bone mineral density (BMD) in patients with MASLD. While BMD is influenced by both alcohol consumption and metabolic dysfunction, the specific relationship between SLD and decreased BMD remains unclear. This study aimed to elucidate the impact of alcohol consumption in patients with MetALD and MASLD, and to identify risk factors for decreased BMD in patients with MetALD in a health examination setting. This retrospective cross-sectional study analyzed individuals who underwent health examinations from April 2018 to March 2023. BMD was determined at the calcaneus using an AOS-10SA bone densitometer. Decreased BMD was defined as T-scores below -1.0 standard deviation or ongoing treatment for osteoporosis. We evaluated 1,945 patients with MetALD and MASLD. The median age was 53 years (interquartile range: 47-61 years), and men comprised 83.9% of the cohort. In multivariate analysis of patients with MetALD and MASLD, the following were identified as independent risk factors for decreased BMD: lean physique (odds ratio [OR]: 0.52, 95% confidence interval [CI]: 0.39-0.70), hypertriglyceridemia (OR: 1.27, 95% CI: 1.02-1.57), male sex (OR: 1.63, 95% CI: 1.06-2.50), older age (OR: 1.02, 95% CI: 1.00-1.03), low creatinine levels (OR: 0.40, 95% CI: 0.17-0.97), and low grip strength (OR: 0.97, 95% CI: 0.95-0.99). Notably, moderate alcohol consumption was associated with a lower risk of decreased BMD (OR: 0.71, 95% CI: 0.55-0.92) compared to no/light alcohol consumption. A total of 535 individuals were diagnosed with MetALD. In these patients, weak grip strength was the only independent risk factor for decreased BMD (OR: 0.96, 95% CI: 0.93-1.00). BMD values showed a weak but significant positive correlation with grip strength measurements (ρ = 0.149, P < 0.001). Our study revealed that moderate alcohol consumption was associated with preserved BMD in patients with MetALD and MASLD, while patients with weak grip strength appear to be at higher risk for decreased BMD in MetALD. Low grip strength likely indicates reduced systemic skeletal muscle mass, suggesting a potential relationship with decreased BMD. Our findings suggested that patients with weak grip strength should be prioritized for BMD assessment in MetALD, enabling early intervention for bone health management. The study highlights the complex relationship between moderate alcohol consumption, muscle strength, and bone health in patients with MetALD and MASLD. (420 words).