Frailty in Older Patients in the Emergency Department: Assessment, Prognostication, and Clinical Application

Older patients presenting to the emergency department (ED) have markedly heterogeneous physiological reserve and functional vulnerability that are not captured by chronological age or acute illness severity alone.Frailty, a state of increased vulnerability to stressors and reduced homeostatic recovery, represents an integrative framework for prognostication in this population.This review summarizes the concepts and instruments of frailty assessment applicable to the ED (Clinical Frailty Scale [CFS], PRISMA-7, Identification of Seniors at Risk, Fatigue, Resistance, Ambulation, Illnesses, and Loss of Weight [FRAIL] scale and its Korean version [K-FRAIL], frailty index, and electronic frailty index), and synthesizes evidence that frailty predicts mortality, hospital and intensive care admission, length of stay, ED revisits, functional decline, and institutionalization.Because most brief screening instruments demonstrate high sensitivity but limited specificity, this review highlights the value of combining frailty with vital sign-based acuity and early-warning scores and linking a positive screen to evaluation of geriatric syndromes.Korean ED evidence, including a CFS-adjusted Korean Triage and Acuity Scale, the prognostic value of CFS across age groups and in older people with critical illness, and Korean tool validation, is integrated throughout, and a frailty-based ED care pathway adapted to Korean practice is proposed.Frailty assessment should guide, not determine, treatment scope by allowing early risk stratification that leads to comprehensive geriatric assessment, multidisciplinary intervention, tailored discharge planning, and shared decision-making with patients and families.