As many of us know, Penn State is infected with sick college students. I find it nearly impossible to go ten seconds without someone either sneezing or coughing profusely around me in our SC 200 class. When we are sick, many of us take medication like Benadryl to control or cough or runny nose. We are also well aware that there are numerous side-affects listed on the packaging but we barely bother to read around 30 side-affects. Could dementia be one of those side affects?
Dementia is a very serious condition that affects millions of people around the world. If you are not aware of dementia, it is something caused by our brains which causes things like memory loss, impaired thinking, confusion, and mental decline. Dementia is most common in elderly people over age 60.
Benadryl is a very common over-the-counter drug that is widely available at places like Walgreens and CVS all across the world. Benadryl is part of a class of drugs called antihistamines. Antihistamines work by blocking histamine receptors in our body which can cause things like runny nose and insomnia.
In this case, the null hypothesis would be that antihistamines like Benadryl do nothing to cause dementia. While, the alternative hypothesis would be that in fact antihistamines play a role in dementia. Scientists can choose to either accept or reject the null hypothesis.
A study conducted by JAMA Internal Medicine in 2015 studied the potential link between anticholinergic use and dementia. Anticholinergics are drugs that block acetylcholine from reaching the body (antihistamines like Benadryl are anticholinergic drugs). The study was a longitudinal study, which as we mentioned in class in the “is smoking bad for you” session, is a observational study that studies some sort of trend across a long period of time. The longitudinal study tracked 3,434 people aged 65 and older over 10 years. Specifically, the study looked into constant use of anticholinergics and dementia. New participants were enrolled into study to replace previous participants that passed away. Computerized pharmacy dispensing data was used to see if the participants were using anticholinergics frequently. This data showed the name of the person, the amount, and how they took the prescribed anticholinergics.
The results of the study showed a positive correlation between anticholinergic use and dementia in the participants. 797 out of the 3,434 participants developed during the course of the study. Participants who took more anticholinergics had a higher risk of developing dementia. A number of third variables like college education, regular physical activity, and smoking were taken into account.
In my opinion, this is one of the most important studies ever conducted in medicine. I believe that the study was extremely well conducted by accounting for a number of third variables and had an incredibly large sample size. Most of my previous blogs contained studies that had 20-50 people, this one had just under 3,500. Although this study definitely proves the positive correlation between anticholinergic use and dementia, we know that correlation need not equal causation. This study does not prove that if you take anticholinergics you will get dementia, it just shows that there is a link between the two. Reverse causation can be ruled out due to the lapse of time.
MS, Shelly L. Gray PharmD. “Strong Anticholinergics and Incident Dementia.”The JAMA Network. Jama Internal Medicine, 01 Mar. 2015. Web. 20 Oct. 2016.