4AT screening for delirium in dementia: meta-analysis of diagnostic performance.

Delirium is frequently underdiagnosed in older adults, especially those with dementia, due to overlapping clinical features. In this meta-analysis, we evaluate the diagnostic performance of the 4 'A's Test (4AT) in detecting delirium specifically among dementia patients. Five eligible diagnostic accuracy studies were identified in a systematic search in six databases, comprising 1,304 older adults, including 482 with dementia. Pooled sensitivity and specificity were 88 and 79%, respectively, with a diagnostic odds ratio of 32.0, indicating strong discriminatory power. The 4AT high sensitivity supports its use as an initial screening tool to rule out delirium in dementia patients, especially in acute or resource-limited settings. However, moderate specificity highlights the need for confirmatory assessments in positive cases. In this review, we underscore the clinical utility of the 4AT for rapid delirium detection in complex geriatric populations and recommend further research on its performance across dementia subtypes and healthcare environments.