GINKGO BILOBA AND ALZHEIMERS DISEASE
Sep 11, 2012
By Trevor Shewfelt, Pharmacist at the Dauphin Clinic Pharmacy
The day before my kids first day of school, I got to have my own back to school experience. I went to the University of Manitoba for a day long course on giving injections. The course was interesting, but the campus was fascinating. I think this was my first time back on campus since I left pharmacy school. To begin with the nursing building my course was in didnt exist when I went to the U of M. The pharmacy building I went to was still standing, but it now says Biological Sciences not pharmacy on it. The new pharmacy building is at the Health Sciences Center, and Ive actually never even seen it. The biggest shock to me was Tache Hall. I knew Tache was being converted and was no longer going to be a student residence. However seeing the building I lived in for 3 years all boarded up and the new huge glass residence behind it was disconcerting. Apparently the University has moved on without me.
Pharmacy knowledge is always moving on too. When I was leaving pharmacy school, ginkgo biloba was going to be the next big thing. This herb was going to prevent Alzheimers disease. Alzheimers disease is a degenerative disease of the brain and the most common kind of dementia. Some small scale animal and human trials seemed to indicate that ginkgo could fix or delay Alzheimers disease. It was thought that ginkgo might reduce the oxidative damage in the brain, might make the blood a little thinner and thus get more blood to different parts of the brain.
It looks like ginkgo might not be good a preventing Alzheimers disease after all. The biggest study yet on Ginkgo and Alzheimers disease was done in 2008. DeKosky et al. published a paper in the November 2008 JAMA called, Ginkgo biloba for prevention of dementia: a randomized controlled trial. It was a nice big trial with over 3000 participants who were over 75 years old. Half of the group got ginkgo and half got a sugar pill. They were followed for about 6 years. In the sugar pill group, 246 got dementia. In the ginkgo group 277 got dementia. For a trial this size, 246 and 277 are basically the same number. This trial said you were as likely to get dementia if you took ginkgo or a sugar pill. If you remember Alzheimers disease is a type of dementia, this trial was pretty good proof that ginkgo does not prevent Alzheimers disease.
Although the DeKosky JAMA trial is still the biggest and possibly best ginkgo and Alzheimers disease trial, another more recent trial just came out from France. Vellas et al published a paper in the Sept 2012 Lancet Neurology that looked at 2854 patients over the age of 70. Half were given ginkgo and half got a sugar pill. They were followed up for about 5 years. After 5 years the researchers found 61 of the ginkgo group had developed Alzheimers disease and 73 people in the sugar pill group had developed Alzheimers disease. For a study of this size, those numbers should be considered identical. So again it seems pretty clear ginkgo doesnt prevent Alzheimers disease.
So what does prevent Alzheimers disease? The full answer is we dont know because there are many things we still dont understand about this condition. We do know some of the risk factors for Alzheimers disease, though. Some risk factors you cant change. The older you get, the more likely you are to develop Alzheimers disease. If you are female, you are more likely to get Alzheimers disease. You have to pick you parents carefully, as genetics plays some role in developing this type of dementia. But researchers think there are some simple things you can do to reduce your risk. The most common type of Alzheimers disease probably does have a genetic component, but lifestyle matters as well. Some identical twin studies show that up to 60% of the risk of getting Alzheimers disease seems to come from lifestyle, not from genes.
Some of the risk factors you can change include keeping your heart healthy. Keeping your blood pressure down and cholesterol under control reduce your risk of dementia as well as heart attack and stroke. Take care of your diabetes. There is research into effects of insulin and the brain. Some people are even calling Alzheimers disease Type 3 diabetes. The existence of Type 3 diabetes is still controversial, but the better you control your diabetes, the less likely you are to get Alzheimers disease. Get a good education. Again more research needs to be done, but the suggestion from researchers is that people with University degrees, who know a second language, or in other ways have crammed more knowledge into their heads are better off. The theory says that as brain cells are damaged by early Alzheimers disease, the people who have learned more have more brain cells that can be disabled and still be able to function. Finally stop banging your head into the wall. The more head injuries a person gets, the more likely they are to have Alzheimers disease when they get older.
My kids enjoyed their first day of back after summer holidays. Now is their time to enjoy elementary school. I got quite nostalgic watching the first year university students walk around the U of M. It is their time to discover the wonders of University life. As I am now decades older than those first year students, my presence on campus seems antiquated. Ginkgo biloba for Alzheimers disease and I should just ride into the sunset and admit our time has come and gone.
As always if you have any questions or concerns about these or other products, ask your pharmacist.
The information in this article is intended as a helpful guide only. It is not intended to be used as a substitute for professional advice. If you have any questions about your medications and what is right for you see your doctor, pharmacist or other health care professional.
We now have this and most other articles published in the Parkland Shopper on our Website. Please visit us at www.dcp.ca
Lancet Neurology article : http://www.thelancet.com/journals/laneur/article/PIIS1474-4422(12)70206-5/abstract
JAMA article : http://jama.jamanetwork.com/article.aspx?articleid=182920
Alzheimer Society Canada : http://www.alzheimer.ca/en