Abstract
BACKGROUND: Malnutrition is a complication of chronic kidney disease (CKD). Whether malnutrition, assessed via the geriatric nutritional risk index (GNRI), is associated with the incidence and risk of CKD in older individuals remains unclear. METHODS: Data from the National Health and Nutrition Examination Survey and the UK Biobank database were used. Older participants over 60 years old with available data for GNRI assessment and CKD diagnosis were enrolled. Logistic regression models and Cox regression models were used to assess associations between the geriatric nutritional risk index and the risk of and mortality associated with CKD. RESULTS: This study enrolled 13,162 participants from the NHANES and 66,326 participants from the UK Biobank. We identified 6,135 and 16,662 CKD patients in the NHANES and UK Biobank, respectively, with the majority being male (74% in the NHANES and 52% in the UK Biobank). The average age of CKD patients was 72.3 (SD 7.2) years in the NHANES and 64.9 (SD 2.9) years in the UK Biobank. The median follow-up times of older CKD patients were 81 months and 162 months in the NHANES and UK Biobank, respectively. According to the cross-sectional analysis, individuals with a lower GNRI had an increased likelihood of having CKD, with odds ratios of 1.38 (95% CI: 1.05-1.80, P = 0.020) in the NHANES and 2.35 (95% CI: 1.89-2.92, P < 0.001) in the UK Biobank. According to our analysis of the risk of incident CKD in the UK Biobank, a lower GNRI was associated with a greater incidence of CKD (HR: 1.11, 95% CI: 1.04-1.18; P = 0.002). According to the analysis of the risk of mortality, a lower GNRI was associated with an increased risk of death among older CKD patients (NHANES: HR: 1.69, 95% CI: 1.13-2.53, P = 0.011; UK Biobank: HR: 2.28, 95% CI: 1.94-2.69, P < 0.001). CONCLUSION: Malnutrition assessed by the GNRI was significantly and independently associated with the incidence of CKD. Moreover, CKD patients with malnutrition also have a high risk of mortality.