Geriatric Nutritional Risk Index as a Possible Predictor of Decline in Kidney Function in Older People

Background: The Geriatric Nutritional Risk Index (GNRI) is associated with morbidity and mortality in older individuals. Our study explored the relationship between GNRI, decline in kidney function, and all -cause mortality in older individuals. Methods: This retrospective cohort study analyzed data from participants aged >= 60 years who underwent a general health checkup between 2002 and 2018. The primary exposure was the GNRI, divided into quartiles. The primary and secondary outcomes were a decline in kidney function assessed using the 5 -year estimated glomerular filtration rate (eGFR) and all -cause mortality, respectively. Results: The analysis included a total of 1,599 participants (median age, 63 years; interquartile range [IQR], 61-67; 54% males). The mean +/- standard deviation of GNRI was 114 +/- 7. Compared with the highest GNRI quartile, the lower GNRI quartiles were associated with steeper 5 -year slopes in eGFR, with a fully adjusted beta coefficient and 95% confidence intervals (CIs) of -0.50 (-0.86, -0.14), -0.29 (-0.63, 0.05), and -0.19 (-0.53, 0.14) for the first, second, and third GNRI quartiles, respectively. The median follow-up duration was 7.4 years (IQR, 4.6-12.4). During this period, we identified 108 deaths (7.8 per 1,000 person -years). The first GNRI quartile was associated with all -cause mortality compared to the highest GNRI quartile (hazard ratio of 2.20; 95% CI 1.23, 3.95). Conclusion: Nutritional status, as evaluated using the GNRI, was associated with 5 -year changes in kidney function and all -cause mortality in older individuals.