Delirium Masquerading as Dementia

doi:10.1017/9781108985055.024

Chapter 24 - Delirium Masquerading as Dementia

from Section 3 - Treatment of the Dementias

Published online by Cambridge University Press: 17 November 2025

Sara C. LaHue and

S. Andrew Josephson

Edited by

Bruce L. Miller and

Bradley F. Boeve

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Bruce L. Miller: Affiliation:
University of California, San Francisco
Bradley F. Boeve: Affiliation:
Mayo Clinic, Minnesota

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Summary

Delirium is an acute disturbance in mental status characterized by fluctuations in cognition and attention that affects more than 2.6 million hospitalized older adults in the United States annually, a rate that is expected to increase with the aging population. Delirium is associated with a myriad of poor outcomes, including prolonged hospital stay and readmission, loss of independence, new or accelerated cognitive impairment, and death. The relationship between delirium and dementia is complex, as dementia is one of the most significant risk factors for delirium, and delirium is independently associated with an increased risk of subsequent cognitive decline. Here, we provide a current review on the epidemiology, evaluation and management of older adults with delirium, focusing on those instances where it can be mistaken for a dementing illness.

Keywords

delirium dementia confusion encephalopathy hospitalization

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Type: Chapter
Information: The Behavioral Neurology of Dementia , pp. 399 - 412

DOI: https://doi.org/10.1017/9781108985055.024 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2025

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