Relationship between probable sarcopenia and nutritional disorders as evaluated using the Geriatric Nutritional Risk Index and serum phosphorus concentration in maintenance dialysis patients: A cross-sectional study

Abstract Background To explore the relationship between sarcopenia and nutritional disorders, as evaluated using the Geriatric Nutritional Risk Index (GNRI) and serum phosphorus concentration (P). Methods: This cross-sectional study analyzed 909 Japanese maintenance hemodialysis patients from a multicenter hemodialysis unit. The nutritional indices (GNRI and P) and sarcopenia indices [grip strength and Short Physical Performance Battery (SPPB)] were evaluated in all patients. Multiple logistic regression analysis was performed with the sarcopenia indices as dependent variables and GNRI only, P only, and combined GNRI and P as independent variables adjusted for patient attributes. The odds ratio (OR) and 95% confidence interval (95% CI) for the reference value were calculated by setting the category reference value to GNRI ≥90 and P to 3.6-5.0 mg/dL. The main outcome measure was presence of probable sarcopenia. Results: Grip strength was associated with decreased GNRI only (OR: 2.27, 95% CI: 1.64-3.16) and decreased GNRI and P (OR: 3.77, 95% CI: 1.49-9.53). In addition, SPPB was associated with decreased GNRI only (OR: 1.78, 95% CI: 1.30-2.44) and decreased GNRI and P (OR: 8.82, 95% CI: 3.52-22.12). Conclusions: Nutritional disorders, in which both GNRI and P are decreased, are strongly related to sarcopenia compared with nutritional disorders in which only GNRI or only P is decreased.