Study disproves link between Lyme and Alzheimer's diseases

Study disproves link between Lyme and Alzheimer's diseases

(Medical Xpress)—New research from the University of Toronto Mississauga definitively puts to rest a theory that Lyme disease causes Alzheimer's.

While researching his book "The Alzheimer's Epidemic—Searching for Causes and a Cure" (Emeritus Books), U of T Mississauga Professor Emeritus Danton O'Day was intrigued to discover studies and popular professional opinion supporting a potential link between Lyme disease and Alzheimer's deaths. In 2012, there were 315 reported cases of Lyme disease in Canada, although the Canadian Lyme Disease Foundation estimates the actual number to be in the thousands. Alzheimer's disease affects 750,000 Canadians.

Lyme disease is an illness that is spread to humans through the bite of ticks infected with corkscrew-shaped bacteria known as Borrelia burgdorferi. Part of the spirochete family of bacteria, B. burgdorferi can cause neuroborreliosis, which can lead to dementia. Alzheimer's disease causes a similar loss of cognitive ability and, eventually, death.

Studies suggested a link between the two diseases because earlier research had detected the presence of spirochete bacteria, including B. burgdorferi, in the brains of individuals with Alzheimer's disease.

"Lyme disease can be easily detected and cured with antibiotics," O'Day said. "In contrast, the causes of Alzheimer's disease remain unknown and there is no cure."

Study disproves link between Lyme and Alzheimer's diseases
Neuroimaging showing normal (top row) and Alzheimer's (bottom row) brains. Credit: Danton O'Day

To investigate whether there was any substance to this unproven but potentially fatal relationship, O'Day collected data from the U.S. Centers for Disease Control and Prevention on reported incidence of Lyme disease and Alzheimer's-related deaths. Together with Andrew Catalano, a recent PhD graduate from O'Day's research group who is now a post-doctoral fellow at City College of New York, O'Day compared data to see if states with high incidences of Lyme disease also showed a high incidence of deaths related to Alzheimer's.

The pair found, in fact, that the 13 states with the highest incidence of Lyme disease actually reported the lowest number of deaths due to Alzheimer's. Furthermore, seven of the states with high incidences of Alzheimer's deaths were among the 13 states with the lowest incidence of Lyme disease. Vermont was the only state that reported a high incidence of both diseases.

"Statistical analyses revealed a complete lack of correlation between the two diseases, strongly suggesting that Lyme disease could not be the cause Alzheimer's," O'Day said.

The United States is the only source to report location-specific data on the two diseases, but O'Day says that the findings are equally relevant in Canada. "While such complete data does not exist in Canada to make equivalent comparisons, there are no valid reasons this conclusion would not hold here as well as for any other country world-wide."

"Because of this growing impact Alzheimer's disease will have in Canada and world-wide, we need to understand the true factors that underlie the disease," said O'Day. "We need to quickly rule out concerns, like Lyme disease, that unnecessarily cause widespread fear and interfere with attempts to fully understand the causes of Alzheimer's disease."

The research was published in the August 2014 issue of the Journal of Alzheimer's Disease.

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More information: Danton H. O'Day, Andrew Catalano. "A Lack of Correlation between the Incidence of Lyme Disease and Deaths due to Alzheimer's Disease." Journal of Alzheimer's Disease, May 19, 2014. DOI: 10.3233/JAD-140552
Journal information: Journal of Alzheimer's Disease

Citation: Study disproves link between Lyme and Alzheimer's diseases (2014, July 17) retrieved 23 October 2019 from
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Jul 18, 2014
Perhaps another view on the study of whether or not lyme is linked to alzheimer's can be taken, by the results. If Lyme incidence is low when Alzheimer's is in high existence then isn't it possible that lyme disease is not getting diagnosed and treated leading to a high instance of Alzheimer's. In areas where Alzheimer's is low and the incidence of Lyme Disease is high, could it not be because Lyme is being recognized and treated and thus not as many are coming down with Alzheimer's. In Vermont where there is equal prevalence, perhaps it is due to the law recently passed allowing doctors to treat Lyme and perhaps as more doctors begin to recognize and treat Lyme Disease in Vermont, the incidence of Alzheimer's will begin to go down. Perhaps this study actually proves that untreated or insufficiently treated Lyme Disease does in fact lead to many cases of Alzheimer's Disease. Thus this study shows there is a strong correlation between Lyme and Alzheimer's Disease.

Jul 18, 2014
With no 100% accurate Lyme test, there's no way to know just how Alzheimer's is caused. Has a proven cause of Alzheimer's been found? Areas high in diseases such as MS, Lupus, Alzheimer's etc with no reason why should be investigated. There has to be reason, and there has to be a caused

Jul 18, 2014
What a ridiculous way to prove a point or disprove a scientific finding. Have a look at Judith Miklossy's work finding Borrelia spirochete and Dental spirochetes in Alzheimer brains
Lancashire university dental college published last year finding Dental pathogens in Alzheimer brains thus confirming in part Miklossy's work.
Dr MacDonald was the first to publish his finding of Borrelia DNA in Alzheimer brains many years ago - what needs to happen is for researchers to properly look using the right methodology at Alzheimer brains to see if more research can replicate these findings - using wrong techniques no doubt will not find Borrelia but using correct techniques may well find Borrelia as it has syphilis spirochetes.
An interesting presentation from Dr MacDonald on Spirochetal Alzheimer's https://www.youtu...XrdJ55A8

Jul 19, 2014
Their logic falsely assumes diagnosis is quickly followed by death in both diseases, thus not allowing time for pts to move. It also assumes that death from both is always clearly indicated on death certificates. In other words, death from either is so slow that ppl have time to change states; LD and AD could contribute to death but not be on the primary cause on the certificate. Using geography to analyze and diagnose zoonotic diseases assume both animals and ppl have limited mobility. ........... I prefer to trust MacDonald autopsy research at this point. http://alzheimerb...tations/

Jul 21, 2014
AD takes decades to develop, which means gathering the geographical data would be quite complicated - the statistician would have to track each patient through all of their previous residences in order to correlate various possible regions where the original onset occurred.
There is now a growing mass of evidence that infection can start the degenerative processes in many of the dementias as well as ALS and Parkinson's. But the most glaringly obvious evidence of infection concerns borreliosis and Alzheimer's - from research that stretches back to the late 1980s, and which has now been confirmed using state-of-the-art DNA technology.
At the inaugural meeting of the Spirochaetal Alzheimer's Association, this evidence was presented by one of the key researchers, Dr Alan B MacDonald:
Does huge increases in AD cases over past decades parallel a similar rise in Lyme disease cases? A good epidemiology project perhaps?

Jul 22, 2014
The very title of this article is misleading at best. The title of the original paper suggests no "correlation", by no means proof. I agree with the comments above and that the study does not take into account variables that would impact the results. The CDC data incorporates only reported cases? Again,how can an epidemiological study have value over actual post mortem brain biopsies? Who funded this study? There is not sufficient space in the comments field to list the numerous biological studies that prove the connection between Alzheimer's and Lyme. I have first hand knowledge of a loved one who died of Alzheimer's and had Lyme that was treated according to the IDSA guidelines and presumably eradicated.

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