Associations of Myosteatosis with Osteoporosis, Vertebral Fractures, and Long-Term Prognosis in Patients with Cirrhosis

Background: Myosteatosis is increasingly recognized as a clinically relevant skeletal muscle abnormality associated with adverse clinical outcomes. This study aimed to investigate the associations of myosteatosis with osteoporosis, vertebral fractures, and prognosis in patients with cirrhosis. Methods: This retrospective study included 139 patients with cirrhosis. Skeletal muscle radiodensity was calculated as the mean Hounsfield unit (HU) at the L3 level on computed tomography. Myosteatosis was defined as <33 HU for men and <28 HU for women, using previously reported sex-specific cutoffs derived from a cohort of patients with cirrhosis. Sarcopenia and osteoporosis were diagnosed according to the Japanese Society of Hepatology and World Health Organization criteria, respectively. Vertebral fractures were assessed using lateral thoracolumbar radiographs. Results: The prevalences of myosteatosis, osteoporosis, vertebral fractures, and sarcopenia were 62.6%, 32.4%, 30.9%, and 36.0%, respectively. During a median follow-up of 67.1 months, 37 liver-related deaths (26.6%) occurred. The prevalence of myosteatosis was significantly higher in patients with osteoporosis (p = 0.003), vertebral fractures (p = 0.021), and sarcopenia (p < 0.001) than in those without the respective conditions. The coexistence of myosteatosis and sarcopenia was associated with a higher prevalence of osteoporosis and vertebral fractures than either condition alone or neither condition (p < 0.001 for both). Osteoporosis remained independently associated with myosteatosis after multivariable adjustment (adjusted odds ratio = 3.04; p = 0.039). Liver-related mortality-free survival was significantly lower in the myosteatosis group than in the non-myosteatosis group (p = 0.007). Furthermore, myosteatosis was independently associated with liver-related mortality (adjusted hazard ratio = 2.78; p = 0.026). Conclusions: Myosteatosis is associated with bone diseases and poorer survival, highlighting the importance of comprehensive musculoskeletal assessment in patients with myosteatosis.