Geriatric nutritional risk index as a screening tool for malnutrition in patients on chronic peritoneal dialysis

Abstract

Background: Malnutrition is common among peritoneal dialysis (PD) patients. Recently, the Geriatric Nutrition Risk Index (GNRI) was found to be a reliable tool for screening malnutrition in hemodialysis patients. However, the GNRI has not been validated in PD patients.

Methods: We studied 314 unselected, adult PD patients from a single dialysis unit. We compared their GNRI scores with their comprehensive Malnutrition-Inflammation Scores (MIS) and 7-point Subjective Global Assessment (SGA) scores. We randomly selected 106 patients for a repeated assessment, and the changes in their three indices were compared.

Results: Baseline GNRI was significantly correlated with MIS (r = -0.487, P < .0001) and SGA (r = 0.234, P < .0001). When MIS >or=6 was defined as malnutrition, the sensitivity and specificity of GNRI <or=93 in predicting malnutrition were 68.0% and 67.7%, respectively. When SGA <or=5 was used to define malnutrition, the sensitivity and specificity were 54.5% and 71.1%, respectively. The change in GNRI was correlated with the change in MIS (r = -0.244, P = .012) and overall SGA score (r = 0.266, P = .006), respectively. When an increase in MIS was defined as a worsening of nutrition, the sensitivity and specificity of GNRI were 45.7% and 81.7%, respectively. When a decrease in SGA was used to define a worsening of nutrition, the sensitivity and specificity were 42.3% and 87.0%, respectively.

Conclusions: Although GNRI is significantly correlated with other nutritional indices, it is not sensitive for screening malnutrition in PD patients. Serial measurements of GNRI are also not sensitive in detecting a change in nutritional status. Further study is needed to identify a simple and reliable tool for the assessment and monitoring of nutritional status in PD patients.