Abstract: Objective To investigate the efficacy of different nutritional assessment tools in evaluating the nutritional status of elderly patients undergoing maintenance hemodialysis (MHD) and analyze their correlation with frailty and adverse outcomes. Methods A total of 146 elderly patients (aged ≥65 years) undergoing MHD were enrolled. Nutritional status was assessed using the Nutritional Risk Screening 2002 (NRS2002), Mini-Nutritional Assessment-Short Form (MNA-SF), and Malnutrition Inflammation Score (MIS), followed by consistency analysis. Patients were divided into frailty and non-frailty groups, as well as survival and death groups, based on the FRAIL scale (Fatigue, Resistance, Ambulation, Illness, Loss of Weight) and adverse outcomes. Differences in clinical data and nutritional status between groups were compared. Multivariate logistic regression was used to analyze the relationship between NRS2002, MNA-SF, MIS, and frailty. Kaplan-Meier survival analysis and multivariate Cox regression were employed to evaluate the relationship between NRS2002, MNA-SF, MIS, and prognosis.  Results The incidence of malnutrition assessed by NRS2002, MNA-SF, and MIS was 41.78%, 43.84%, and 52.74%, respectively. MIS showed good consistency with NRS2002 and MNA-SF (Kappa=0.701, 0.714), while NRS2002 and MNA-SF had low consistency (Kappa=0.427). The proportion of malnutrition assessed by NRS2002 (χ²=5.385, P=0.020), MNA-SF (χ²=5.023, P=0.025), and MIS (χ²=8.119, P=0.004) was significantly higher in the frailty group than in the non-frailty group. Multivariate logistic regression revealed that NRS2002 (OR=3.903, 95%CI: 1.393～10.937, P=0.010) and MIS (OR=4.574, 95%CI: 1.435～14.585, P=0.010) were independent risk factors for frailty. The proportion of malnutrition assessed by NRS2002 (χ²=10.905, P＜0.001), MNA-SF (χ²=6.837, P=0.009), and MIS (χ²=12.296, P＜0.001) was significantly higher in the death group than in the survival group. Kaplan-Meier analysis showed that the cumulative survival rate of malnourished patients (assessed by NRS2002, MNA-SF, MIS) was significantly lower than that of patients with normal nutrition (χ²=7.375, 9.681, 12.252, P=0.007, 0.002, <0.001, respectively). Multivariate Cox regression indicated that NRS2002 (HR=2.587, 95%CI: 1.210～5.533, P=0.014), MNA-SF (HR=2.663, 95%CI: 1.218～5.821, P=0.014), and MIS (HR=3.697, 95%CI: 1.494～9.147, P=0.005) were independent risk factors for adverse outcomes.  Conclusion  MIS shows good consistency with NRS2002 and MNA-SF in assessing nutritional status in elderly MHD patients. Both MIS and NRS2002 are risk factors for frailty and adverse outcomes and may be more suitable for clinical prognosis evaluation..

Key words: Nutritional risk screening 2002, Mini-nutritional assessment-short form, Malnutrition inflammation score, Maintenance hemodialysis, Frailty, Death