# Early Warning Scores in Emergency Department Patients Aged 80 Years or Older

## TL;DR

This study evaluates how well five early warning scores predict short-term health decline in patients 80+ years old in Italian emergency departments.

## Contribution

The study provides a comparative analysis of EWS performance in older patients, identifying REMS as the most reliable for those over 94 years.

## Key findings

- All five EWSs showed fair discrimination in predicting clinical deterioration within 24 hours.
- REMS outperformed other scores in calibration and improved with increasing age beyond 94 years.
- Oxygen supplementation, systolic blood pressure, and Glasgow Coma Scale were key predictors for patients aged 87+.

## Abstract

This prognostic study assesses the accuracy of 5 early warning scores to predict death or intensive care unit admission within 24 hours of being seen in the emergency department in patients aged 80 years or older in Italy.

Do early warning scores (EWSs) accurately predict short-term clinical deterioration among older patients in the emergency department (ED)?

In this prognostic study including 50 645 Italian patients aged 80 years or older, 5 evaluated EWSs showed fair discrimination. The National Early Warning Score (NEWS) achieved the highest area under the curve, while the Rapid Emergency Medicine Score (REMS) showed superior calibration and positive predictive value and was the only score whose performance improved with increasing age.

NEWS and its derivatives offered greater sensitivity, whereas REMS provided higher precision that may reduce alarm fatigue and outperformed other scores in older patients.

Early warning scores (EWSs) are widely used tools to support triage and risk stratification in the emergency department (ED). However, data on their performance in identifying clinical deterioration among acutely ill adults aged 80 years or older are scarce.

To evaluate and compare the performance of 5 EWSs for predicting short-term clinical deterioration in ED patients aged 80 years or older.

This retrospective prognostic study included all consecutive nontrauma ED visits by patients aged 80 years or older between January 2015 and December 2024 at a large urban teaching hospital in Rome, Italy.

Physiologic parameters recorded at ED admission were used to calculate 5 EWSs: National Early Warning Score (NEWS), National Early Warning Score 2 (NEWS2), Modified Early Warning Score (MEWS), Rapid Emergency Medicine Score (REMS), and International Early Warning Score (IEWS).

The primary outcome was clinical deterioration, defined as death or intensive care unit (ICU) admission within 24 hours of ED arrival. Discrimination was assessed by area under the receiver operating characteristic curve (AUROC), calibration by the Brier score, and age-related performance by spline regression. Comparative contributions of variables were analyzed using Shapley additive explanations (SHAP) values.

Among 50 645 patients (median age, 85 years [IQR, 82-88 years]; 54.6% females), 1233 (2.4%) experienced clinical deterioration. All EWSs demonstrated fair discrimination (AUROC range, 0.747 [IQR, 0.731-0.763] for MEWS to 0.782 [IQR, 0.767-0.798] for NEWS). Whereas NEWS achieved the highest AUROC, REMS had the best calibration (Brier score, 0.0220; 95% CI, 0.0208-0.0232). Discriminatory performance declined with increasing age beyond 90 years except for REMS, whose predictive accuracy improved among patients older than 94 years. For patients aged 87 years or older vs 80 to 86 years, oxygen supplementation (SHAP difference, 0.59), systolic blood pressure (SHAP difference, 0.32), and Glasgow Coma Scale score (SHAP difference, 0.40) were the strongest predictors of clinical deterioration.

In this prognostic study of EWSs conducted among ED patients aged 80 years or older, all scores provided acceptable short-term prognostic accuracy. REMS demonstrated the most consistent performance in patients aged 94 years or older, supporting its use for targeted risk stratification in this population.