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

Abstract

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.