Acetylcholine and delirium

The neurotransmitter acetylcholine has been implicated in animal and human studies of delirium. This chapter will briefly review the clinical studies focussing on measurement of serum levels of anticholinergic activity in del irious states. Three approaches have been taken. First, to identify medicat ions currently prescribed that have subtle anticholinergic effects. The cur rent 'list' includes 48 commonly prescribed medications, Second, to associa te serum anticholinergic activity with delirium in various clinical states including postcardiotomy delirium, postelectroconvulsive delirium, deliriou s elderly medical inpatients, and nursing home patients. Third, to interven e in patients with elevated anticholinergic activity by reducing known anti cholinergics and correlating this reduction with clinical measures of cogni tion and delirium. Our most recent data investigates the impact of antichol inergics on demented patients. Rates of delirium were significantly higher in patients receiving larger numbers of anticholinergics.