Early Diagnosis of Delirium in Geriatric Patients in Emergency Departments: A Systematic Review and Meta-Analysis

Background: Acute confusional state, or delirium, is a common neuropsychiatric disorder in older adults, particularly in emergency departments. It is associated with high morbidity and mortality, as well as difficult detection. Its early identification is crucial to prevent complications and improve prognosis. This study aims to identify and analyze available strategies for the early diagnosis of delirium in geriatric patients in emergency departments. Methods: A literature review and meta-analysis were conducted between 2020 and 2026 using the PubMed, Scopus, Web of Science, CINAHL, and Cochrane databases (PRISMA 2020). To estimate the prevalence of patients with delirium in emergency departments, a meta-analysis was performed using Stats Direct statistical software (Version 4). Methodological quality was evaluated according to the Oxford Centre for Evidence-Based Medicine levels of evidence. Results: Eleven studies were included, demonstrating that delirium in emergency departments is highly prevalent among older adults, particularly those with dementia, polypharmacy, or functional impairment. The 4AT scale was the most frequently used screening tool, notable for its strong sensitivity. Hypoactive delirium emerged as the most common subtype and carried the poorest prognosis. Furthermore, its presence was associated with longer hospital stays, increased complications, and higher mortality rates, while a lack of training among healthcare staff continues to limit early detection. The meta-analysis detected no publication bias and revealed a 20.6% prevalence of delirium among patients in emergency departments. Conclusions: One in five patients attending the emergency department presents with delirium. Delirium in geriatric emergency care demands a structured clinical response grounded in prevention, early detection, and professional training. Integrating validated diagnostic tools and reinforcing the role of nursing professionals are key to improving patient outcomes and safety.