Delirium is a disturbance in mental abilities that results in confused thinking and a reduced awareness of the environment. It affects 8 to 17 percent of older patients in the emergency department (ED) setting.

It is unclear how often delirium in the ED persists into hospitalization or what impact it has on long–term function and cognition. To try to answer that, Jin Han, MD, MSc, and colleagues performed a prospective cohort study of 228 ED patients who were 65 years or older.

Their report, published in the Journal of the American Geriatrics Society, concluded that delirium in the ED is not a transient event. It persisted into hospitalization in 77 percent of cases for a median duration of three days.

Patients’ function and cognition were assessed at six months. The longer the delirium lasted, the more patients’ function and cognition declined. These findings suggest that ED delirium interventions to preserve patients’ long–term function and cognition are needed.