Comparison of geriatric nutritional risk index and creatinine index in short-term mortality prediction in maintenance hemodialysis patients.

BACKGROUND

The aim of this study is to analyze and compare the predictive values of the Geriatric Nutritional Risk Index (GNRI) and Creatinine Index (CI) in the short-term mortality of maintenance hemodialysis patients and to determine their best cut-offs.

METHODS

A total of 169 adult hemodialysis patients were included in this retrospective, cross-sectional, and single-center study. The demographic, clinical, and laboratory data of the month in which the patients were included in the study were obtained from their medical files and computer records. All-cause death was the primary outcome of the study during a 12-month follow-up after baseline GNRI and CI calculations.

RESULTS

The mean age of the study population was 57 ± 16 years (49.7% were women, 15% were diabetic). During the one-year observation period, 19 (11.24%) of the cases died (8 CV deaths). The optimal cut-off value for GNRI was determined as 104.2 by ROC analysis [AUC = 0.682 ± 0.06, (95% CI, 0.549-0.815), p = 0.01]. The low GNRI group had a higher risk for all-cause and CV mortality compared to the higher GNRI group (p = 0.02 for both in log-rank test). The optimal sex-specific cut-off was 12.18 mg/kg/day for men [AUC = 0.723 ± 0.07, (95% CI, 0.574-0.875), p = 0.03] and was 12.08 mg/kg/day for females [AUC = 0.649 ± 0.13, (95% CI, 0.384- 0.914), p = 0.01]. Patients with lower sex-specific CI values had higher all-cause and CV mortality (p = 0.001 and p = 0.009 in log-rank test, respectively). In multivariate cox models, both GNRI [HR = 4.904 (% 95 CI, 1.77-13.56), p = 0.002] and sex-specific CI [HR = 5.1 (95% CI, 1.38-18.9), p = 0.01] predicted all-cause mortality. The association of GNRI with CV was lost [HR = 2.6 (CI 95%, 0.54-13.455), p = 0.22], but low CI had a very strong association with CV mortality [HR = 11.48 (CI 95%, 1.25 -104), p = 0.03].

DISCUSSION

In hemodialysis patients, GNRI and CI have similar powers in predicting all-cause short-term mortality. The association of CI with all-cause death depends on gender. On the other hand, sex-specific CI predicts CV mortality better than GNRI.