Development of an emergency department risk score for in-hospital mortality in elderly patients with urinary tract infection

BACKGROUND: Urinary tract infection (UTI) is among the most prevalent bacterial infections globally, particularly impacting elderly populations in emergency departments (EDs). This study aimed to develop and validate an ED-specific risk score predicting in-hospital mortality for elderly patients with UTI. METHODS: Using data from the MIMIC-IV-ED database, we enrolled patients aged 65 or older with confirmed UTI admitted to wards or ICUs. Variables were selected through stepwise logistic regression using Bayesian Information Criterion in the derivation cohort (70 %), and dichotomized by optimal cut-offs identified by Youden's index. A point-based scoring system was developed from regression coefficients. Internal validation was performed on a separate validation cohort (30 %) assessing discrimination (AUC), calibration, and clinical utility using decision curve analysis. RESULTS: . Scores ≥4 predicted a mortality rate of 29.9 % compared to 4.5 % in lower-scoring groups, with sensitivity and specificity of 59.6 % and 93.1 %, respectively, and a negative predictive value of 95.5 %. Validation cohort performance remained consistent (AUC 0.73), and the model outperformed established risk scores. CONCLUSIONS: The EARL-UTI score provides an easily implemented bedside tool for rapid identification of elderly ED patients at high risk for in-hospital mortality, potentially guiding early intervention and resource allocation decisions. Future prospective multicenter studies are necessary to confirm its clinical impact and generalizability.