alzheimer’s disease linked to commonly used medications

ALZHEIMER’S DISEASE has become an epidemic here in America, with everyone and his brother trying to figure out what causes it (if you click the link, you’ll see that the list is significant).  According to the most recent issue of JAMA Internal Medicine (another of the many scientific journals published by the American Medical Association) you can now add any number of common drugs to this list. 

Certain kinds of ANTIDEPRESSANTS, SLEEPING AIDS, MUSCLE RELAXERS, VALIUM, Antihistamines, and drugs taken to control urinary incontinence (Antimuscarinics), as well as certain anti-ulcer drugs and cardiovascular medications that are known as “Anticholinergics” (they block the neurotransmitter acetylcholine).  Listen to what a popular online encyclopedia has to say about acetylcholine:  “One well-supported function of acetylcholine (ACh) in the brain’s cortex is increased responsiveness to sensory stimuli, a form of attention.….    Some forms of learning and plasticity in the cortex appear dependent on the presence of acetylcholine”  In other words, hinder the ability of actylcholine to work as it should and some of the numerous effects you are going to get include distractedness, unresponsiveness, and an inability to learn. 

This is almost exactly what researchers from the University of Washington’s School of Pharmacy discovered and subsequently published in their study (Cumulative Use of Strong Anticholinergics and Incident Dementia), which is a continuation of a study that started over two decades ago.  None of the individuals had Dementia when they started the study, but after an average of 7.3 years, nearly one in four did; with 80% of these being diagnosed as Alzheimer’s.  The medicated group had nearly double the amount of Dementia as did the non-medicated group.  And there’s a punch-line to this study, but it won’t leave you laughing.

In a sister article published in the same issue of the journal (Adverse Cognitive Effects of Medications: Turning Attention to Reversibility), we discover that unfortunately these cognitive side effects of anticholinergic drugs cannot be reversed simply by pulling patients off their meds.  Listen to what the authors say. “The risk for dementia was consistent when comparing participants with recent and past heavy use of such medications with nonusers, suggesting that the adverse cognitive effects are permanent. Other studies have consistently shown similar results.”  Other studies?  What other studies?

Although the press is treating this study that came out two days ago as though it is big news, rest assured that there is nothing new here.  Not only did we see the same thing six years ago in the very same journal (Drugs With Anticholinergic Properties, Cognitive Decline, and Dementia in an Elderly General Population), but we saw it late last summer as well.   We can’t really “oooohhh” and “aaahhh” about how scary this most recent study is, when the September issue of the British Medical Journal carried an almost identical one (Benzodiazepine Use and Risk of Alzheimer’s Disease: Case-Control Study).  Should we be surprised by any of this?  How could we be, when it’s the very nature of what we call “EVIDENCE-BASED MEDICINE“.