Using Anti-cholinergic Drugs May Increase Cognitive Decline In Older People

The study looked at the effects of taking a medication with anticholinergic properties on the annual change in thinking abilities of 870 Catholic nuns and clergy members who were an average of 75 years old. All of the participants were part of the Rush Religious Orders Study, an ongoing, longitudinal, clinical study of older people without dementia.

All of the participants underwent annual cognitive tests and reported their medication use for an average followup period of eight years. During the study, 679 people took at least one medication with anticholinergic properties.

The study found those people who took anticholinergic drugs saw their rate of cognitive function decline 1.5 times as fast as those people who did not take the drugs.

"Our findings point to anticholinergic drugs having an adverse impact on cognitive performance in otherwise normal, older people," said study author Jack Tsao, MD, DPhil, Associate Professor of Neurology at Uniformed Services University in Bethesda, Maryland, and member of the American Academy of Neurology. "Doctors may need to take this into account before prescribing these commonly used drugs."

Tsao says more research is needed to determine the mechanism behind the rapid memory loss apparently associated with anticholinergic drugs and to identify which drugs, in particular, may be more likely to impair cognition.

This research was presented at the American Academy of Neurology 60th Anniversary Annual Meeting in Chicago, April 17, 2008. The study was supported by the American Philosophical Society Daland Grant and grants from the National Institute on Aging.