The clinical frailty scale score in older persons (≥ 65 years) admitted via the emergency department: a prospective cohort study

BACKGROUND: Frailty is becoming a major health factor among older adults. Emergency department risk stratification is effective with the Clinical Frailty Scale (CFS). This study examined the association between CFS level and hospital outcomes including in hospital mortality, length of hospital stay, and 30-day readmission rate in older patients admitted through the emergency department of a tertiary hospital in Jordan. METHODS: King Abdullah University Hospital conducted this prospective cohort study from September 2024 to June 2025. Emergency department admissions of 949 65-year-olds were included. Patients were divided into mild/non-frail (CFS 1-5, n = 252) and moderate/severe frail (CFS 6-8, n = 697) groups. Study participants with CFS 9 (n = 12) were eliminated. The main outcome was hospital death. Secondary outcomes were stay length and 30-day readmission rates. Continuous variables were assessed for normality (Kolmogorov-Smirnov test) and expressed as mean ± SD or median (Interquartile range), with Student's t-test or Mann-Whitney U test for group comparisons. Multivariable logistic regression was performed to identify independent predictors of mortality, adjusting for age, sex, comorbidities, clinical presentation, and length of stay. RESULTS: Mean age was 75.4 ± 7.3 years, of which 53.8% were male. The moderate/severe frail patients were older (76.7 ± 7.2 vs. 71.8 ± 6.4 years, p < 0.001) and had an extended hospital stay (7.6+-8.6 vs. 4.2 ± 4.5 days, p < 0.001). There was a significant increase in in-hospital mortality in the moderate/severe frailty group (20.6% vs. 4.8%, OR 5.2, 95% CI 3.0-10.4, p < 0.001). There was a progressive rise in mortality risk with CFS scores: CFS 5 (OR 8.3), CFS 6 (OR 12.8), CFS 7 (OR 28.2), and CFS 8 (OR 64.0) versus CFS 1-4. Frailer patients also had a greater 30-day re-admission rate (24.8% vs. 10.4% OR 2.8, 95% CI 1.79-4.47, p < 0.001). CONCLUSIONS: The Clinical Frailty Scale is a robust predictor of in-hospital mortality among older patients in the emergency department. Routine CFS evaluation should be instituted, potentially enhancing risk classification and clinical decision-making in this vulnerable population. TRIAL REGISTRATION: Not applicable.