Study of 500,000 Medical Records Links Viruses to Alzheimer's Again And Again

Ed1937

https://tinyurl.com/yckhkjzj  

White Crane

Very interesting, Ed.  Thanks for posting.

Michael Ellenbogen

 From everything I know this just seems very false to me and this is the first time I am reading or hearing this.

Larrytherunner

I have read several articles in the past about virus infections increasing the risk of Alzheimers. One way to reduce the risk is to reduce immune system neuroinflammation that increases with the exposure of viruses and virus fragments. Even if viruses are not active, virus fragments can still stimulate microglia to produce substances that increase inflammation. The common anti-inflammatory asthma drug, montelukast, which reduces leukotriene immune signaling, could possibly be used to reduce neuroinflammation and treat Alzheimers. 

A small FDA clinical trial using montelukast to treat participants with early stage Alzheimers was completed at Emory University in November 2022. I was able to contact a physician envolved in the trial and he emailed me that they are still analyzing the data. I am hopeful that the results will be announced soon. If the small trial is successful, then I expect that a much larger FDA trial at Emory seeking FDA approval will be coming.

Sligo177

Very interesting, I hope more investigation takes place on this one.  You read so many theories about how Alzheimer's begins - this could be significant for prevention.  Thanks for sharing!

Joe C.

This is far from a new theory. My my aunt (mother’s sister) developed an unspecified dementia in the 1970s and her doctors attributed it to having encephalitis in an outbreak in early 1920s when she would been 10-12 years old. The moving Awakenings starring Robin Williams is loosely based in fact about a doctor working with institutionalized patients who survived the same encephalitis outbreak and had severe cognitive decline.

gampiano

This is so interesting. When my Dad was diagnosed with Parkinson's, back in the 1960s, he participated in an L DOPA clinical trial. Several of the patients in the trial had been ill with encephalitis during the 1920's, including him. He responded to the drug with great improvement in mobility, decrease in tremors, etc. Unfortunately, after he returned home, the hallucinations began, and he had to be placed in a facility. The doctors were convinced that the virus was instrumental in his PD. 

Larrytherunner

I just read about this study in Alzforum and it mentioned that the data was taken from medical billing codes of hospitalized patients. For most of these viruses identified, people are unlikely to be hospitalized, so the study is based on the more serious cases. There may be a connection but it may not be as great as the study suggests. Covid is another virus that is going to get a lot more scientific attention about its future neurological effects. This study reminds me of the importance of getting vaccinated when possible.

https://www.alzforum.org/news/research-news/nothing-sneeze-viruses-raise-risk-neurodegenerative-disease

Josie in Podunk

That’s a very interesting article and not the first time I have heard of a virus as a possible cause.

My late father-in-law developed dementia from a rare kidney infection that went to his brain.

When I told our doc about it he had heard of it and added that blood test to the regular protocol done to see if there was a definable root cause for my hubby’s dementia.  I’m sorry I don’t remember the name of it, but it is about a mile long.

We remain with the dx of dementia of unknown cause.

Crushed

folks this is correlation research .  the weakness in such medical research is you don't know which  way causation goes. 

eg married people live longer than single people  
but we have no idea  if they are from the same pool
 

eg both viruses and Alzheimer's could be related to some kind of vulnerable brain  

   Most prominently, the pairings are only associations; they do not prove the viruses are causing the brain diseases. There may be genetic reasons someone is more susceptible to both viruses and Parkinson’s, for example. And other environmental exposures likely also play a role in causing neurodegenerative diseases.
 In fact, a key part of the authors’ analysis undermines the notion that viruses are triggering disease, says Cornelia van Duijn, a genetic epidemiologist at the University of Oxford. As part of the study, the team used the Finnish data to examine the strength of the association for each virus-disease pairing at 1, 5, and 15 years after infection. Because neurodegenerative diseases take years or decades to develop, one might expect the highest risk after 15 years. But the authors found the opposite: For virtually every pairing, the elevation in risk was greatest 1 year after infection and diminished over time.
“That is usually a flag for epidemiologists,” van Duijn says, indicating that the viral infections might not be causing the disease, but rather be a byproduct of it. It’s known, she says, that in the years leading up to a diagnosis of dementia, for instance, people become “metabolically and immunologically a mess.”

  

https://www.science.org/content/article/study-links-viral-infections-alzheimer-s-parkinson-s-many-caveats

  
  
 

Crushed

Note the word LINKS  in correlation research is considered incredibly misleading

Chains have links they are known real connections.  
 
eg If  A causes B
And   A causes C
  
B and C are not Linked

Lane Simonian

Between definite causation and correlation is a vast expanse.  There is a great desire to find a single cause for Alzheimer's disease because then you could potentially find a simple treatment that would work for everyone (an anti-viral medication, for example).  Unfortunately, there are likely multiple causes of Alzheimer's disease not only in general but often within one person.  The following I think got it right:

"In the absence of a definitive ultimate cause, it may be that the symptoms of Alzheimer's disease can arise from many different types of insult to the brain. There have been several papers, says Dr Le Guillou, that have found correlations between various infectious organisms and Alzheimer's. "It could be a bit like the Mississippi river," says Dr Hardy. "You can start in all sorts of places, but eventually you're going to end up in New Orleans." If Alzheimer's is a general response to all sorts of neurological triggers then it may be that the fungal infections found by Dr Carrasco are simply one of a long list of causes."