Serum anticholinergic activity levels and delirium in the elderly.

This article will briefly review the clinical studies focusing on measurement of serum levels of anticholinergic activity in delirious states. Three experimental approaches have been taken. First, to identify medications currently prescribed that have subtle anticholinergic effects. The current "list" includes 48 commonly prescribed medications. Second, to associate serum anticholinergic activity with delirium in various clinical states including postcardiotomy delirium, postelectroconvulsive delirium, delirious elderly medical inpatients, and nursing home patients. Third, to intervene in patients with elevated anticholinergic activity by reducing known anticholinergics and correlating this reduction with clinical measures of cognition and delirium. Our most recent data investigate the impact of anticholinergics on demented patients. Prevalence of delirium was significantly higher in patients receiving larger numbers of anticholinergics.