SAT-787 Lower Muscle Area and Immunosuppressive Agents are Associated with Greater Bone Loss in Liver Transplant Recipients

Abstract Disclosure: S. Baek: None. J. Park: None. S. Cho: None. N. Hong: None. E. Min: None. J. Lee: None. D. Joo: None. Y. Rhee: None. Liver transplantation is a critical treatment for end-stage liver disease, but musculoskeletal complications significantly affect long-term outcomes. We introduce the Skeletal and Muscular Investigation in LiVER Transplantation (SiLVER) study to prospectively investigate changes in bone mineral density (BMD), muscle mass, muscular function, and body composition parameters in liver transplant recipients during the pre- and post-transplant periods. This comprehensive study assesses musculoskeletal health through biochemical, radiographic, and functional measures, with extensive muscular parameters including hand grip strength, weight-corrected peak jump power, and Short Physical Performance Battery (SPPB) collected serially.Among the 313 participants enrolled to date, Hepatitis B (HBV) was the most common indication for liver transplantation (37.4%), followed by alcohol-related liver disease, liver cirrhosis (non-B, non-C), and hepatitis C. 44 patients (14.1%) died during the follow-up period. Preliminary analysis revealed that 44.14% had osteopenia, 19.14% had osteoporosis, and 42.38% were diagnosed with sarcopenia at baseline. Corticosteroids and tacrolimus were used in most patients post-transplant (98.08% each), followed by mycophenolate (81.47%), mTOR inhibitors (46.33%), and cyclosporine (33.55%). Of 117 HBV patients, 47% were treated with entecavir and 42% were treated with tenofovir. The median daily corticosteroid dose was 9 mg in prednisolone equivalents.In analysis of 94 participants who completed the 1-year follow-up, significant BMD loss was observed at the femoral neck (-5.2%, p<0.0001) and total hip (-4.9%, p<0.0001). Post-transplant improvements were observed in grip strength (20.8%, p=0.0001) and weight-corrected peak jump power (19.3%, p=0.0003). Muscle mass decreased significantly (-4.49 cm2/m2, p<0.0001), with increases in muscle density (1.92 HU, p=0.0219). Increases in both subcutaneous fat (4.50 cm2/m2, p=0.0350) and visceral fat (8.07 cm2/m2, p=0.0001) were noted. A random forest regressor model and SHapley Additive exPlanations (SHAP) were used to identify the most impactful predictors of BMD loss. Higher tacrolimus doses, lower mycophenolate doses, and low muscle area were found to have the most significant impact on BMD decline.As one of the first large-scale, longitudinal, multidimensional studies in this field, the SiLVER study has the potential to provide valuable insights to guide evidence-based strategies for improving musculoskeletal health and optimizing perioperative and postoperative care. Presentation: Saturday, July 12, 2025