Serum creatinine-to-cystatin C ratio as an indicator of sarcopenia in hemodialysis patients

Background and aims: In hemodialysis patients, sarcopenia is common and related to morbidity and mortality. In non-dialysis patients, the serum creatinine-to-cystatin C (Cre/Cys-C) ratio is a marker of sarcopenia. Its clinical utility in hemodialysis populations, however, is still unknown. Our study aimed to determine whether sarcopenia could be detected using the Cre/Cys-C ratio in hemodialysis patients.Methods: This retrospective cross-sectional study included 85 hemodialysis patients whose handgrip strength (HGS) and bioimpedance analysis-estimated skeletal muscle index (SMI) were assessed. Sar-copenia was diagnosed as a combination of reduced muscle strength (women: HGS <18 kg; men: HGS <28 kg) and decreased muscle mass volume (women: SMI <5.7 kg/m2; men: SMI <7.0 kg/m2).Results: Sarcopenia was observed in 33 (38.8%) patients. Patients with sarcopenia had a significantly lower Cre/Cys-C ratio than those without (1.3 & PLUSMN; 0.2 vs 1.7 & PLUSMN; 0.3, respectively; p < 0.0001). The Cre/Cys-C ratio was independently associated with HGS (5 = 0.303, p = 0.011) and SMI (5 = 0.376, p = 0.0007). After adjustment for sex and age, the C-statistic of the Cre/Cys-C ratio that predicted sarcopenia was 0.898 (95% CI [0.827, 0.969], p < 0.0001). Moreover, as Cre/Cys-C ratios increased, the risk of sarcopenia significantly decreased (adjusted OR: 0.665 for each 0.1 increase in the Cre/Cys-C ratio) (95% CI [0.501, 0.857], p = 0.0002).Conclusion: The Cre/Cys-C ratio may be a helpful prediction tool for sarcopenia in patients receiving hemodialysis.& COPY; 2023 The Author(s). Published by Elsevier Ltd on behalf of European Society for Clinical Nutrition and Metabolism. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).