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Delirium in elderly adults: diagnosis, prevention and treatment


Delirium is a common and serious acute neuropsychiatric syndrome with core features of inattention and global cognitive dysfunction. The etiologies of delirium are diverse and multifactorial and often reflect the pathophysiological consequences of an acute medical illness, medical complication or drug intoxication. Delirium can have a widely variable presentation, and is often missed and underdiagnosed as a result. At present, the diagnosis of delirium is clinically based and depends on the presence or absence of certain features. Management strategies for delirium are focused on prevention and symptom management. This article reviews current clinical practice in delirium in elderly individuals, including the diagnosis, treatment, outcomes and economic impact of this syndrome. Areas of future research are also discussed.

Key Points

  • Delirium is a frequent cause and a serious complication of hospitalization and has important implications from both a functional and an economic standpoint

  • Delirium is potentially preventable and treatable, but major barriers, including underrecognition of the syndrome and poor understanding of the underlying pathophysiology, have hampered the development of successful therapies

  • Neuroimaging has identified structural changes, including cortical atrophy, ventricular dilatation and white matter lesions, to be predictors of delirium

  • Current evidence suggests that disruption of neurotransmission, inflammation or acute stress responses might contribute markedly to the development of delirium

  • Delirium is not always transient and reversible, and it can result in long-term cognitive changes

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Figure 1: Relationships between various etiological factors in delirium.
Figure 2: Outcomes of delirium.


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The authors are supported by NIA PHS Grants K24AG000949 (SK Inouye) and K23AG031320 (TG Fong), and Grant IIRG-08-88737 (SK Inouye) from the Alzheimer's Association. Désirée Lie, University of California, Irvine, CA, is the author of and is solely responsible for the content of the learning objectives, questions and answers of the Medscape-accredited continuing medical education activity associated with this article.

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Correspondence to Tamara G. Fong.

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Fong, T., Tulebaev, S. & Inouye, S. Delirium in elderly adults: diagnosis, prevention and treatment. Nat Rev Neurol 5, 210–220 (2009).

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