Predictors of Skeletal Muscle Index for Patients Treated With Hemodialysis

There is an increased risk of skeletal muscle mass (SMM) loss among patients with stage 5 chronic kidney disease treated with maintenance hemodialysis (MHD). The reduced SMM considerably influences the development of protein-energy wasting (PEW). Patients who develop PEW have higher hospitalization and mortality rates than those without PEW. This study determined if key variables could predict SMM Index (SMM adjusted for height) in patients receiving MHD.

We conducted a secondary analysis of cross-sectional data obtained from the Rutgers Nutrition and Kidney Database (n = 178). Data were used to calculate both SMM and SMM Index. Univariate and multiple linear regression models explored the relationship between SMM Index and the following variables: serum albumin, urea clearance normalized treatment ratio, normalized protein catabolic rate, serum creatinine, and urea reduction ratio (URR).

Most participants were Black/African American (82.9%), male (59.1%), and obese (39%), with a mean age of 55.9 ± 11.9 years. The median Subjective Global Assessment score was 5, indicating a lower risk of malnutrition. Participants had a mean SMM of 26.4 kg and a median SMM Index of 8.9 kg/m². Univariate regression modeling found URR to be a significant predictor of SMM Index, with increases in the percentage of URR predicting lower SMM Index values. The adjusted regression modeling found similar results, with increases in URR percentage predicting declines in SMM Index.

This study found that URR was a predictor of SMM Index in patients receiving MHD. Further research is required to explore these relationships and provide clinicians with a more extensive array of tools to recognize early signs of SMM loss to prevent the progression of PEW.