Article

Cholinergic deficiency hypothesis in delirium: a synthesis of current evidence.

Warren Alpert Medical School of Brown University, Providence, RI, USA.
The Journals of Gerontology Series A Biological Sciences and Medical Sciences (impact factor: 4.6). 08/2008; 63(7):764-72. pp.764-72
Source: PubMed

ABSTRACT Deficits in cholinergic function have been postulated to cause delirium and cognitive decline. This review examines current understanding of the cholinergic deficiency hypothesis in delirium by synthesizing evidence on potential pathophysiological pathways. Acetylcholine synthesis involves various precursors, enzymes, and receptors, and dysfunction in these components can lead to delirium. Insults to the brain, like ischemia and immunological stressors, can precipitously alter acetylcholine levels. Imbalances between cholinergic and other neurotransmitter pathways may result in delirium. Furthermore, genetic, enzymatic, and immunological overlaps exist between delirium and dementia related to the cholinergic pathway. Important areas for future research include identifying biomarkers, determining genetic contributions, and evaluating response to cholinergic drugs in delirium. Understanding how the cholinergic pathway relates to delirium may yield innovative approaches in the diagnosis, prevention, and treatment of this common, costly, and morbid condition.

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Keywords

biomarkers
 
cause delirium
 
cholinergic deficiency hypothesis
 
cholinergic drugs
 
cholinergic function
 
cholinergic pathway
 
cholinergic pathway relates
 
cognitive decline
 
common
 
delirium
 
dementia
 
future research
 
genetic contributions
 
immunological overlaps
 
immunological stressors
 
morbid condition
 
neurotransmitter pathways
 
potential pathophysiological pathways
 
review examines current understanding
 
various precursors
 

Tammy T Hshieh