Geriatric nutritional risk index as a predictor of 28-day and 365-day mortality in patients with heart failure complicated by sepsis: A retrospective cohort study using the MIMIC-IV database

Objective: To evaluate the association between the Geriatric Nutritional Risk Index (GNRI) at ICU admission and mortality in patients with heart failure complicated by sepsis, a high-risk population in which the prognostic value of this validated malnutrition risk assessment tool remains underexplored. Methods: Patients with heart failure and sepsis were identified from the Medical Information Mart for Intensive Care (MIMIC-IV) database and stratified into four GNRI groups. The primary endpoints were 28-day and 365-day all-cause mortality. Survival analysis used Kaplan-Meier curves and Cox proportional hazards models. Linearity was assessed using restricted cubic splines (RCS), while GNRI’s predictive performance was evaluated using receiver operating characteristic (ROC) curves. Results: Altogether, 1713 patients with heart failure complicated by sepsis were identified in the present study. Kaplan-Meier analysis revealed 28-day mortality rates of 40.44% (high-risk) vs . 25.27% (no-risk) ( P <.001), with a similar trend for 365-day mortality (63.75 % vs. 43.96%, P <.001). RCS confirmed a linear inverse relationship between GNRI and mortality. Cox regression demonstrated that each unit GNRI increase reduced 28-day (hazard ratio [HR], 0.99; 95% confidence interval [ CI ] 0.98-1.00) and 365-day mortality risk (HR, 0.98; 95% CI 0.98-0.99). ROC analysis indicated a moderate predictive value of GNRI for 28-day all-cause mortality (AUC=0.58, sensitivity=66.61%, specificity=45.62%, P <.001) and 365-day all-cause mortality (AUC=0.60, sensitivity=66.52%, specificity=51.28%, P <.001). Furthermore, the addition of GNRI significantly enhanced the predictive performance of the SAPSII (AUC increased from 0.69 to 0.70, P =.02), SOFA (AUC increased from 0.73 to 0.74, P =.02), and LODS (AUC increased from 0.67 to 0.68, P =.03) scores, with these improvements achieving statistical significance. Conclusions: Admission GNRI is an independent risk factor for in-hospital mortality in ICU patients with heart failure complicated by sepsis. GNRI scores serve as a valuable prognostic indicator for assessing mortality risk in this patient population.