Wisdom Wednesday: These Common Drugs May Raise Your Risk of Dementia

A landmark study has linked the long-term use of certain anticholinergic drugs to a higher risk of dementia later on. This investigation is believed to be the “largest and most detailed” study to date into long-term anticholinergic use and dementia risk.

Anticholinergics work by blocking a chemical messenger, or neurotransmitter, called acetylcholine that carries brain signals for controlling muscles. They are used to treat a variety of conditions, from Parkinson’s disease and loss of bladder control to asthma, chronic obstructive pulmonary disease, and depression.

Anticholinergics for depression, such as amitriphtyline, dosulepin, and paroxetine, have previously been liked to higher risk of dementia, even when they were used up to 20 years beforehand. Some studies have also suggested that use of any anticholinergic is linked to raised risk of dementia.

But the new study – which was led by the University of East Anglia (UES) in the United Kingdom and is now published in The BMJ – discovered that long-term use of only certain types of anticholinergics is linked to higher dementia risk. It confirms the link to long-term use of anticholinergics for depression, and for Parkinson’s disease and loss of bladder control. However, the study found no link between increased dementia risk and other anticholinergic drugs, such as antihistamines and medications for abdominal cramps.

For their investigation, the researchers used data from the Clinical Practice Research Database, which contains anonymized records for more than 11 million people across the U.K. The researchers used a system called the Anticholinergic Cognitive Burden (ACB) scale to score the anticholinergic effect of the drugs that the patients had been prescribed. An ACB score of 1 meant that a drug was “possibly anticholinergic,” whereas a score of 2 or 3 meant that it was “definitely anticholinergic.” Altogether, they analyzed more than 27 million prescriptions.



Analysis revealed that drugs with an ACB score of 3 that had been prescribed for depression, Parkinson’s disease, and loss of bladder control were linked to higher risk of dementia up to 20 years “after exposure.” No such link was found, however for drugs that scored 1 on the ACB scale, nor for respiratory and gastrointestinal drugs that scored 3.

My Take:
In an editorial linked to the study, two professors agree that “As suggested by the guidelines, anticholinergics in general should be avoided in older adults.” How about just avoided regardless of age? After all, the studies show a link at least 20 years after exposure.

The study failed to list any of the common names for these drugs. Although the list of anticholinergic drugs is quite extensive, you may know these – Benadryl, Elavil, Thorazine and any OTC anti-inflammatory drug with PM on the end of it, like Bayer PM or Advil PM.
Many of the drugs on this list have been discontinued or are no longer available in the U.S. They were removed because of obvious, serious side effects. Thorazine is a prime example of a discontinued anticholinergic.

The Bottom Line:
Avoid medications, prescription or OTC, whenever possible. It’s much easier than following a diet. If you feel you must take a drug (the average American takes four prescription drugs per day) make sure it isn’t an anticholinergic.

Source: April 26, 2018 National Institutes of Health