Association Between Geriatric Nutritional Risk Index and the Progression of Chronic Critical Illness and Short-term Prognosis in Sepsis Patients

Background: The impact of nutritional status on the advancement to chronic critical illness (CCI) in sepsis patients is not well understood. This study aimed to explore the connection between the nutritional risk index (GNRI) and the development of CCI. Methods: We performed a retrospective study utilizing data from 7,380 sepsis patients in the MIMIC-IV database. The patients were categorized into High GNRI (n = 3412) and Low GNRI (n = 3968) groups. CCI was defined as an ICU stay >14 days with persistent organ dysfunction. Statistical analyses included univariate and multivariate logistic regression, Cox regression, and curve fitting. Results: Among 7,380 patients (59.1% male, median age 66 years), the high GNRI group had lower body weight, albumin levels, and higher incidence of acute kidney injury. GNRI was a significant predictor of CCI progression (OR: 0.99, 95% CI: 0.98–0.99, p<0.001). After adjusting for confounders, the negative correlation remained (adjusted OR: 0.99, 95% CI: 0.98–1.00, p=0.002). A nonlinear relationship was observed, with an inflection point at GNRI 96.616. Subgroup analyses showed more pronounced protective effects in patients <65 years old and those without cancer, chronic kidney disease, or acute kidney injury. GNRI was also negatively associated with 28-day mortality (adjusted OR: 0.94, 95% CI: 0.93–0.96, p<0.001). Conclusion: GNRI is an independent predictor of CCI progression and 28-day mortality in sepsis patients. Early nutritional assessment and personalized interventions are crucial in critical care settings. Future research should validate these findings in diverse populations and explore targeted nutritional interventions.