Noll Campbell

Anticholinergic drugs are still prescribed for a host of ailments. That’s despite growing awareness of their link to dementia risk and dementia-like symptoms, especially in older adults. Now, researchers are preparing to conduct what they say is the first clinical trial to determine whether the drugs cause cognitive decline. They’ll also look at whether deprescribing can be done safely.

Anticholinergics are used to treat everything from depression to Parkinson’s disease, and include over-the-counter medications such as Tylenol PM. Their link to dementia has been acknowledged for nearly a decade. A recent study tied the drugs to a 50% higher risk of dementia in older adults, McKnight’s has reported.

This fall, researchers from Regenstrief Institute and the Indiana University School of Medicine will start recruiting participants for the new trial, using a $3.3 million grant from the National Institute for Aging. They’ll measure the effects of switching from anticholinergics to alternative medications.

If deprescribing is found to improve cognition, that result will signal “a true causal relationship” between the drugs and dementia, said researcher Noll Campbell, PharmD. And if cognition can be improved without compromising patient safety, he told McKnight’s, the next step will be to find the best way to deprescribe for the many conditions these drugs address.

In the meantime, Campbell advises caution. He recommends that patients remain on their medications until they can discuss the pros and cons of treatment and safe alternatives with their doctor or pharmacist. “Whether benefits for brain health can be realized by stopping these medicines will not be known until we see the results of our trials,” he said.