Myosteatosis is associated with adiposity, metabolic derangements and mortality in patients with chronic kidney disease

Background/Objectives: Myosteatosis has been associated with sarcopenia, and increased mortality risk in patients on hemodialysis. We aimed to explore the associations between myosteatosis, as assessed by computed tomography (CT), with demographic parameters, body composition metrics, muscle strength, metabolic parameters and mortality in patients with chronic kidney disease (CKD). Subjects/Methods: We enrolled 216 patients (age 60.3 +/- 10.6 years, 63% men) with CKD stages 3-5. Abdominal CT scans at the third lumbar vertebra (L3) were used to assess body composition. Abdominal obesity was determined by abdominal adipose tissue (AT), sarcopenia by low skeletal muscle area (SMA) and low handgrip strength. Myosteatosis was evaluated by two parameters using CT scans at L3: mean muscle attenuation and percentage of intermuscular adipose tissue (%IMAT) within SMA. We evaluated the correlation between parameters of myosteatosis with demographic, clinical and metabolic variables. To determine independent predictors of myosteatosis, a multiple linear regression model was fitted. Mortality risk was evaluated with Cox-regression analysis. Results: Both parameters of myosteatosis were independently associated with age, metabolic syndrome, abdominal AT and SMA in the multiple linear regression analysis (adjusted R2 for multiple linear regression: muscle attenuation model 0.535, P < 0.001; %IMAT model 0.462, P < 0.001). Moreover, higher %IMAT and lower attenuation were associated with a higher mortality risk. Conclusion: In patients with CKD, increased myosteatosis, as assessed by abdominal CT, was associated with old age, adiposity, metabolic dysfunction, and higher mortality risk.