Common drugs linked to cognitive impairment

A recent study of 13,000 seniors shows that some over-the-counter medications with anticholinergic activity, which are frequently taken by older adults for diseases like hypertension and congestive heart failure, can cause cognitive impairment and possibly death.

Anticholinergics affect the brain by blocking acetylcholine, a nervous system neurotransmitter. Common products containing diphenhydramine—sold under various brand names such as Benadryl, Dramamine, Excedrin PM, Nytol, Sominex, Tylenol PM and Unisom—have anticolinergic activity, researchers said. Other anticholinergic drugs, such as Paxil, Detrol, Demerol and Elavil, are available by prescription.

“Our findings make it clear that clinicians need to review the cumulative anticholinergic burden in people presenting with cognitive impairment to determine if the drugs are causing decline in mental status,” said study co-author Malaz Boustani, MD, associate professor of medicine at Indiana University School of Medicine. Boustani helped develop the Anticholinergic Cognitive Burden Scale, which was used in the study and supported by the U.S. National Institute on Aging.

The two-year study, part of the Medical Research Council (UK) Cognitive Function and Ageing Studies, a large UK-based longitudinal multi-center study initiative looking at health and cognitive function in older adults, has been published online at the Journal of the American Geriatrics Society.

The study found that older age, lower income and greater number of health conditions increased use of medications with anticholinergic activity. Women were more likely to report taking anticholinergic medications, due to the greater number of health conditions reported by women than by men. Participants living in institutions were more likely to report taking anticholinergic medications.

Researchers concluded the need for follow-up reporting “to determine the degree to which anticholinergics are being prescribed for diseases with significant risk of death.”

The study was funded by the Medical Research Council.

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Anticholinergic Cognitive Burden Scale

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