# Parkinsons caused by neuropathogen traveling up vagus nerve from gut. Curable with antibiotics? **URL:** \ **Category:** Factual Questions\ **Created:** [August 14, 2015, 1:43pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830 "2015-08-14T13:43:46Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [August 14, 2015, 1:43pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/1 "2015-08-14T13:43:46Z")
New findings here - does this mean we can kill ongoing Parkinsons with antibiotics or is the damage already done by the time the disease presents itself? > **[Parkinson's May Spread From Gut to Brain via Vagus Nerve](https://www.medscape.com/viewarticle/849140?src=wnl_edit_newsal&uac=69152PN&impID=792378&faf=1)** > > New observational data support theory that Parkinson's disease may begin in the gastrointestinal tract and spread through the vagus nerve to the brain. > [@](#): > > A large Danish epidemiologic study supports the theory that Parkinson’s disease (PD) may begin in the gastrointestinal tract and spread through the vagus nerve to the brain. Researchers found that patients who have had the entire vagus nerve severed were less apt to develop PD. > > “Their risk was halved after 20 years,” Elisabeth Svensson, PhD, from the Department of Clinical Epidemiology, Aarhus University in Denmark, said in a statement. > [@](#): > > Gut-Brain Connection in PD > > In the past, vagotomy was commonly performed for peptic ulcer, the researchers note in their paper. The two most common procedures were full truncal vagotomy, in which both vagal trunks were severed, and superselective vagotomy, in which only the nerves supplying the fundus and body of the stomach were resected. > > Using prospectively collected Danish registry data, the researchers investigated the risk for PD in 5339 patients who had truncal and 5870 who had superselective vagotomy, in relation to 66,711 and 60,500 matched population controls, respectively. > > A direct comparison of the two vagotomy groups showed that patients who had truncal vagotomy had a lower risk for PD than did those having the superselective procedure, after adjustment for age and sex (adjusted hazard ratio [HR], 0.85; 95% confidence interval [CI], 0.56 - 1.27). After a follow-up period of over 20 years after the date of surgery, the age- and sex-adjusted HR was 0.58 (95% CI, 0.28 - 1.20), the researchers report. > > The risk for PD was also lower after truncal vagotomy when compared with the general population. The overall adjusted HR was 0.84 (95% CI, 0.63 - 1.14). After more than 20 years’ follow-up, the adjusted HR was 0.53 (95% CI, 0.28 - 0.99). > The risk for PD in patients who had superselective vagotomy was similar to that in population controls overall (HR, 1.09; 95% CI, 0.84 - 1.43) and after 20 years (HR, 1.16; 95% CI, 0.80 - 1.70). > > These findings, say the researchers, “suggest that having an intact vagus nerve increases the risk of developing PD. The finding is in accord with a primary pathological process being initiated in the gastrointestinal mucosa, which then uses the vagus as a major entry point into the brain.” ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [August 14, 2015, 2:19pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/2 "2015-08-14T14:19:29Z")
While this looks like an intriguing bit of epidemiology, the evidence presented here is extremely weak. To take one particular quote from the abstract: > [@](#): > > Risk of PD was decreased in patients who underwent truncal (… follow-up of \>20 years: HR = 0.58; 95% CI: 0.28–1.20) compared to superselective vagotomy. Their data shows there might be anywhere from a 72% decrease to a **20% increase** in Parkinson’s disease in patients. IMO, the data is too weak to say that there was a real decrease. In the larger context of research, there’s a “file drawer” effect where negative results never see the light of day. That means there’s a significant bias for publishing false positives. Without more research, I’m going to assume that this is a statistical fluke. (Of course, I work in a field where I can rely on large effect sizes and large samples that are trivial to collect, so it’s not really fair for me to judge the epidemiologists…) ---
**Author:** ![grude](https://avatars.discourse-cdn.com/v4/letter/g/e47774/32.png) [@grude](https://boards.straightdope.com/u/grude)\ **Post date:** [August 14, 2015, 2:25pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/3 "2015-08-14T14:25:50Z")
Couldn’t they be jumping to conclusions with the infection pathway theory? Maybe it is something else related but not an infection pathway. ---
**Author:** ![bordelond](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bordelond/32/150_2.png) [@bordelond](https://boards.straightdope.com/u/bordelond)\ **Post date:** [August 14, 2015, 2:52pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/4 "2015-08-14T14:52:13Z")
This post made me check out the Wikipedia article on the vagus nerve(s). Looking through the “Clinical significance” section … those nerves seem to have fingers in a lot of physiological pies. Depression. Obesity. Heart arrhythmia. Tinnitus. Epilepsy. Parkinson’s. Probably more. That’s astounding. Seems that severing those nerves would be hugely risky., yet is has been done and looks to be sometimes used in place of gastric bypass and such. I wonder how much of this stuff is tried-and-true medicine, and how much is experimental? ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [August 14, 2015, 2:52pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/5 "2015-08-14T14:52:36Z")
More here - study findings seem to be taken seriously > **[Parkinson's disease may start in the Stomach](https://www.sciencenordic.com/denmark-disease-parkinsons-disease/parkinsons-disease-may-start-in-the-stomach/1419678)** > > New study shows Parkinson's disease begins in the gut and creeps up the vagus nerve to the brain, offering hope for new treatments > [@](#): > > “It’s a fantastic experience to attend a conference in the US among world-leading scientists in Parkinson’s disease and see that they are really excited about your research. It gives us hope that our work will help to make a difference,” says Elisabeth Svensson, a post-doc from the Department of Clinical Medicine at Aarhus University in Denmark. > > She is the lead scientist in a new study just published in the journal Annals of Neurology, suggesting that the vagus nerve – which connects the brain with the abdominal tract – may transport Parkinson’s disease from the stomach up into the brain. If the nerve is severed early, the occurrence of Parkinson’s can be halved. > > According to Svensson, whilst they are still unsure how Parkinson’s starts in the gut, this is the first direct evidence that the vagus nerve is involved in the development of the disease in humans. > > “It may bring us one step closer to understanding how Parkinson’s develops,” says Svensson. > > First symptom is constipation > > The new study is extremely important and may settle an on-going dispute amongst scientists studying Parkinson’s disease, according to Per Borghammer, an assistant professor at the Department of Clinical Medicine at Aarhus University in Denmark, and a co-author of the new study. > > “A good number of scientists have doubted that the disease could be transmitted from the gut, even though several studies of animals have suggested this. But now we have outright evidence that the vagus nerve is involved in development of the disease in humans,” says Borghammer. > > “We hope that this suppresses doubts over whether or not Parkinson’s can start in the stomach, and that more money can be focussed into funding research to look at why the disorder starts here,” he says. > > It has long been known that Parkinson’s patients often suffer constipation several years before the typical symptoms of the disease appear – such as shaking, reduced mobility and even depression. > > Last year a group of scientists led by Borghammer showed, using a new PET scanning technique, that Parkinson’s patients have fewer nerve connections in the stomach than healthy people. This indicates that Parkinson’s disease doesn’t just kill brain cells but also the nerve connections between the brain and the gut. ---
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [August 14, 2015, 3:19pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/6 "2015-08-14T15:19:29Z")
> [@bordelond](#): > > Depression. Obesity. Heart arrhythmia. Tinnitus. Epilepsy. Parkinson’s. Probably more. There is a school of thought in autism, mostly consigned to the woo/nonsense/gullible parent file, that some GI disruptions are related to the severity of the deficits. Many kids on the spectrum have “delicate tummies” and proponents claim that a carefully monitored diet (often lapping over into things like gluten-free and nonsense diets of the week) can show improvements in responsiveness and attention. Maybe there is something to this idea. But waiting until there’s more than one questionable study is probably a good idea. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [August 14, 2015, 3:59pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/7 "2015-08-14T15:59:23Z")
> [@lazybratsche](#): > > Their data shows there might be anywhere from a 72% decrease to a **20% increase** in Parkinson’s disease in patients. IMO, the data is too weak to say that there was a real decrease. I think you nailed it. The results aren’t even statistically significant. And that’s after studying tens of thousands of patients. Beyond that, although the results may be consistent with bacterial spread up the vagus, I would think there are other explanations as well. For example, PD is characterized by a deficiency of the neurotransmitter dopamine in a part of the brain called the _substantia nigra_. And that leaves the effect of acetylcholine in the substantia nigra unopposed. Since the vagus is a major source of acetylcholine outflow from the brain, maybe cutting the vagus somehow makes that imbalance worse. At best, the study results are hypothesis generating. In fact, unless I am missing something, I’m surprised it was published in one of the better neurology journals. ---
**Author:** ![cerberus](https://avatars.discourse-cdn.com/v4/letter/c/71e660/32.png) [@cerberus](https://boards.straightdope.com/u/cerberus)\ **Post date:** [August 14, 2015, 10:14pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/8 "2015-08-14T22:14:23Z")
Remarkable that the article survived review (apparently not statistical) without strong comments on limited findings). Given that the intervals contain the null value for the hazard ratio (1), these are null findings, which are consistent with a lack of correlation. However, if the point estimates are consistently below 1, the implication is that there is some sort of risk reduction in there, somewhere. Key here is replication. ---
**Author:** ![cerberus](https://avatars.discourse-cdn.com/v4/letter/c/71e660/32.png) [@cerberus](https://boards.straightdope.com/u/cerberus)\ **Post date:** [August 14, 2015, 10:19pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/9 "2015-08-14T22:19:41Z")
To clarify: as someone who does statistical review for candidate papers, I would be sure to make very strong notes about a paper piling up statistically nonsignificant results and then still claiming an association . Very surprised that a reputable journal would or this one through with the language that it used. Unless they hVe done GR CIs hidden somewhere that have upper limits below 1, no dice. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [August 14, 2015, 10:30pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/10 "2015-08-14T22:30:28Z")
> [@cerberus](#): > > Remarkable that the article survived review (apparently not statistical) without strong comments on limited findings). Given that the intervals contain the null value for the hazard ratio (1), these are null findings, which are consistent with a lack of correlation. However, if the point estimates are consistently below 1, the implication is that there is some sort of risk reduction in there, somewhere. > > Key here is replication. As I said just above, at best the study would seem to be “hypothesis generating”. ---
**Author:** ![Jackmannii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackmannii/32/311_2.png) [@Jackmannii](https://boards.straightdope.com/u/Jackmannii)\ **Post date:** [August 14, 2015, 11:23pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/11 "2015-08-14T23:23:39Z")
> [@](#): > > According to Svensson, whilst they are still unsure how Parkinson’s starts in the gut If you’re convinced that Parkinson’s “starts in the gut”, then this latest study might fan the flames of your enthusiasm. Unfortunately we are far from being able to conclude that “the gut” is indeed the source of the disease, that an infectious agent is the trigger, or that the putative agent does in fact travel the Vagus Superhighway. ---
**Author:** ![cerberus](https://avatars.discourse-cdn.com/v4/letter/c/71e660/32.png) [@cerberus](https://boards.straightdope.com/u/cerberus)\ **Post date:** [August 14, 2015, 11:25pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/12 "2015-08-14T23:25:28Z")
Edited to fix > [@](#): > > To clarify: as someone who does statistical review for candidate papers, I would be sure to make very strong notes about a paper piling up statistically nonsignificant results and then still claiming an association . Very surprised that a reputable journal would or this one through with the language that it used. Unless they hVe done GR CIs hidden somewhere that have upper limits below 1, no dice. Unless they have some hidden hazard ratio CIs with upper bounds below 1, no dice. I could see an issue of replication or hypothesis generation if exploratory analysis yielded statistically significant findings, but there doesn’t seem to be much here. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [August 15, 2015, 1:04pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/13 "2015-08-15T13:04:32Z")
So to recap: 1. Statistically this is perhaps “suggestive” that vagotomy may reduce future risk of PD but is far from conclusive that it does so. 2. A fairly conclusive finding would be interesting and would generate multiple hypotheses. Vagotomy results in _all kinds of stuff_ (higher [heart rate](http://www.ncbi.nlm.nih.gov/pubmed/528030) and a lack of increased heart rate in response to low oxygen, for example) and [parasympathetic tone dysfunction](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2117678/) (of which the vagus nerve is part of) is already related to dementia is ways other than the gut. In fact one neurologist I know makes sure those training under him include need to urinate frequently as part of their neurological review of symptoms as that is a frequent early sign of PD. Increased salivation (also parasympathetic) is also an early sign. 3. Lastly if the very long jump to infectious agent traveling from the gut is made assuming that it is bacterial is another even longer leap. Interesting suggestive work recently that PD may in fact be [a prion disorder.](http://www.neurologyreviews.com/home/article/is-parkinsons-disease-a-prion-disorder/c41a8ef7bb23e28270164bc7337ee82e.html) ---
**Author:** ![cerberus](https://avatars.discourse-cdn.com/v4/letter/c/71e660/32.png) [@cerberus](https://boards.straightdope.com/u/cerberus)\ **Post date:** [August 15, 2015, 1:11pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/14 "2015-08-15T13:11:50Z")
The numbers reported in the abstract are not even suggestive, the point estimates are weak, and completely ignorable given the limits of the confidence intervals. It’s as if the authors and reviewers agreed to ignore the numbers and just go with the gut hypothesis. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [August 15, 2015, 1:28pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/15 "2015-08-15T13:28:47Z")
This is a quibble but there is nothing _magical_ about the 95% CI. That is an arbitrary interval, less strong than 99% and stronger than 90%. I personally would accept this as very weakly suggestive. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [August 15, 2015, 1:57pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/16 "2015-08-15T13:57:07Z")
> [@DSeid](#): > > This is a quibble but there is nothing _magical_ about the 95% CI. That is an arbitrary interval, less strong than 99% and stronger than 90%. > > I personally would accept this as very weakly suggestive. Yes, if for no other reason than the numbers all seem to be going the same direction (albeit none on its own being statistically significant). ---
**Author:** ![Wendell\_Wagner](https://avatars.discourse-cdn.com/v4/letter/w/8491ac/32.png) [@Wendell\_Wagner](https://boards.straightdope.com/u/Wendell_Wagner)\ **Post date:** [August 15, 2015, 2:14pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/17 "2015-08-15T14:14:39Z")
Here’s a recent article from [Cracked.com](http://Cracked.com) about why you should be suspicious of medical journal articles with results not confirmed in several other articles: > **[6 Reasons You Can't Trust Science Anymore](https://www.cracked.com/article_22712_6-ways-modern-science-has-turned-into-giant-scam.html)** > > Publication is an important way for scientists to share research and advance their careers. Here's how it's destroying science. File away in your mind results like this and wait for there to be confirmation from the general medical community. If you go to a doctor and demand to be get a treatment based on this one article, the doctor will tell you that there isn’t enough evidence for it yet. He probably won’t even have heard of it. If you’re super-lucky he might know of studies for it that are being conducted currently that you might get into. Like any study, it’s iffy what would happen to you. You may get better and you may get worse. Otherwise, wait for a general medical acceptance of any new treatment. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [August 15, 2015, 6:23pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/18 "2015-08-15T18:23:03Z")
I’ve always wondered whether many modern disease are caused by infections. Anything that appears mostly randomly in individuals and can’t be tied to a specific failure, is it an infection? Huntingdon’s, hemophilia, sickle cell, etc. can all be tied to specific genetic deficiencies, and their appearance is predictably tied to the genetic lottery and parents. Parkinson’s, Alzheimer’s, Type I diabetes, autism, schizophrenia - many of these sorts of diseases appear randomly, with no specific tie to a single cause. I wonder if they could be the long-term result of some infection, much as post-polio occurs many decades after the initial infection, or syphilis returns to cause senility. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [August 15, 2015, 6:59pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/19 "2015-08-15T18:59:18Z")
> [@cerberus](#): > > The numbers reported in the abstract are not even suggestive, the point estimates are weak, and completely ignorable given the limits of the confidence intervals. > > It’s as if the authors and reviewers agreed to ignore the numbers and just go with the gut hypothesis. You’re saying they had a gut feeling about it? ---
**Author:** ![cerberus](https://avatars.discourse-cdn.com/v4/letter/c/71e660/32.png) [@cerberus](https://boards.straightdope.com/u/cerberus)\ **Post date:** [August 15, 2015, 7:50pm UTC](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830/20 "2015-08-15T19:50:43Z")
The hypothesis in context is that a GI infection travels up the vagus nerve to the brain, so yeah, gut. [Next page](https://boards.straightdope.com/t/parkinsons-caused-by-neuropathogen-traveling-up-vagus-nerve-from-gut-curable-with-antibiotics/727830.md?page=2)