Overview of Delirium and Dementia By Juebin Huang, MD, PhD, Department of Neurology, University of Mississippi Medical Center Reviewed / Revised Feb 2023 View Patient Education Topic Resources Differences Between Delirium... Delirium (sometimes called acute confusional state) and dementia are the most common causes of cognitive impairment, although affective disorders (eg, depression) can also disrupt cognition.