Cardinal features of delirium
What is the cardinal feature of delirium and what are other core features?
Impaired environmental awareness and ability to direct, sustain, and/or appropriately shift attention defines the delirium syndrome.
This impairment is typically of acute onset and waxes and wanes in severity (usually worse at night [“sundowning”]) but there are chronic forms of delirium as well. Emotional, cognitive, psychomotor, circadian rhythm, and sleep–wake disturbances are also common in delirium.
Use of the Delirium Rating Scale-R-98 (DRS-R-98) and other rating scales can assist the diagnoses of delirium and track response to treatment.