Upper Airway Resistance Syndrome (UARS): a common underlying cause for all "chronic complex illnesses"? (ME/CFS, fibro, GWI, etc.)

I'm actually not trying to discuss it in relationship to the UARS theory at the moment. I'm just pointing out the fact that people continually say that PEM is unique to ME/CFS (which is just a name for a syndrome - a group of symptoms that tends to co-occur - after all; no one has confirmed that all ME/CFS is indeed one underlying disease process/disorder), so people should may want to stop doing that if it hasn't been proven to be true.

ETA: Perhaps better said, people should stop presuming ME/CFS is one disorder when this hasn't ben proven to be true (I'm aware that ME/CFS is the only disorder for which PEM appears in the diagnostic criteria, but ME/CFS hasn't been confirmed to be one underlying disorder).

Perhaps this is best discussed under the PEM thread where these points have been considered/discussed. I think someone posted the link in a comment above.
 
I'm actually not trying to discuss it in relationship to the UARS theory at the moment. I'm just pointing out the fact that people continually say that PEM is unique to ME/CFS (which is just a name for a syndrome - a group of symptoms that tends to co-occur - after all; no one has confirmed that all ME/CFS is indeed one underlying disease process/disorder), so people should may want to stop doing that if it hasn't been proven to be true.

ETA: Perhaps better said, people should stop presuming ME/CFS is one disorder when this hasn't ben proven to be true (I'm aware that ME/CFS is the only disorder for which PEM appears in the diagnostic criteria, but ME/CFS hasn't been confirmed to be one underlying disorder).
It feels like you’re arguing against strawmen here. I don’t think it has been claimed in this thread that ME/CFS must be one disorder or that PEM is definitely unique to ME/CFS.

I know you’ll get a lot of unfounded statements on pretty much any other platforms, but those are not S4ME..

And I second Peter in that that discussion belongs elsewhere.

But to address another argument of yours:
Technically PEM could be a symptom of multiple disorders too (though as we would likely both agree it's probably not - or at least restricted to a small # of disorders - I just happen to think that presence/absence of PEM does not make it a different disorder).
That simply is not how you categorise health conditions. The presence or absence of PEM makes such a profound difference to the impact on the person’s health that to not distinguish between the different presentations makes no sense.

And biologically speaking, there has to be a distinct difference between someone with or without PEM, otherwise they would both have it or not have it. We don’t know what that difference is yet, but that isn’t relevant.
 
ETA: Perhaps better said, people should stop presuming ME/CFS is one disorder when this hasn't ben proven to be true (I'm aware that ME/CFS is the only disorder for which PEM appears in the diagnostic criteria, but ME/CFS hasn't been confirmed to be one underlying disorder).

I don't think ME/CFS is a single disorder either, due to the lack of specificity of the diagnosis method, but UARS presents quite differently to ME/CFS in terms of symptoms. Some doctors may well misdiagnose it (ME/CFS instead of something else like UARS) because doctors often make mistakes but UARS is definitely not the primary cause of most chronic illnesses.
 
I don't think ME/CFS is a single disorder either, due to the lack of specificity of the diagnosis method, but UARS presents quite differently to ME/CFS in terms of symptoms. Some doctors may well misdiagnose it (ME/CFS instead of something else like UARS) because doctors often make mistakes but UARS is definitely not the primary cause of most chronic illnesses.
Sorry, I think we're supposed to be keeping this thread inactive at the moment (so we can discuss this in DMs if you want), but how could you possibly know that "UARS presents quite differently to ME/CFS in terms of symptoms?" Only a sleep doctor who sees UARS patients on a regular basis could know that, and apparently sleep doctors who do, like the ones who wrote this article on UARS (Dr. Gold is not an author by the way), think that "tiredness/fatigue, fibromyalgia, headaches, insomnia, cold extremities, fainting, and low/normal BP" is how UARS patients often present. That sounds very similar to ME/CFS to me...
 
ME/CFS is not simply a list of vaguely defined symptoms. It's not just sleep doctors but doctors who focus on ME/CFS who can tell the difference.

"Tiredness" in particular can mean very different things.

The tiredness that a UARS patient experiences is quite different (since it is usually due to the breathing difficulties during sleep) and that leads to a big difference in the daily experience of a patient. Any daytime sleepiness in particular is experienced very differently.

Many ME/CFS patients do go to sleep clinics and find out that is not the issue. CPET studies likewise show airway resistance is rarely a problem.

(and it is the PEM discussion that is being redirected elsewhere)
 
ME/CFS is not simply a list of vaguely defined symptoms. It's not just sleep doctors but doctors who focus on ME/CFS who can tell the difference.
Well, according to sleep doctors who diagnose UARS patients, they usually seek treatment for a "functional somatic syndrome" rather than sleep-disordered breathing or excessive daytime sleepiness before eventually being diagnosed with UARS: https://pubmed.ncbi.nlm.nih.gov/15510051/

And in the article I shared with you in the previous post it said "It is frequent that UARS is misinterpreted as chronic fatigue syndrome, fibromyalgia" (I'm proposing it's not misinterpreted but that it can cause them)
"Tiredness" in particular can mean very different things.
Agreed.
The tiredness that a UARS patient experiences is quite different (since it is usually due to the breathing difficulties during sleep) and that leads to a big difference in the daily experience of a patient. Any daytime sleepiness in particular is experienced very differently.
No, tiredness in UARS patients is not due to work of breathing (please read my OP). The majority of people with sleep-disordered breathing are asymptomatic (and they have the same "breathing difficulties" as those who are symptomatic). All of this is laid out in my OP along with the theory about what is causing the symptoms in sleep-disordered breathing patients but here is a good thread on Bluesky that discusses it too (it focuses on sleepiness because that's all they collected data on).
Many ME/CFS patients do go to sleep clinics and find out that is not the issue.
Very few sleep clinics evaluate for UARS and if they do they go based on RERA/RDI criteria which is not reliable; at the vast majority of sleep clinics when people have an AHI <5 they are told they have no problem and sent away. Even when OSA (AHI ≥ 5) is diagnosed and CPAP is prescribed, it's hardly ever manually titrated in the lab to eliminate inspiratory flow limitation (IFL), and people are usually put on an auto-titrating setting which may or may not be eliminating IFL.

IMO the only reliable way to diagnose UARS (or OSAS for that matter) is: presence of IFL + daytime symptoms + improvement in symptoms with adequate treatment that is actually significantly reducing/eliminating IFL.

So essentially UARS is never being ruled out.
CPET studies likewise show airway resistance is rarely a problem.
UARS/OSAS has nothing to do with airway resistance while awake, it is caused by pharyngeal narrowing/collapse during sleep due to relaxation of airway muscles + something else (again, since the majority of people with pharyngeal narrowing/collapse during sleep are asymptomatic), and Dr. Gold's theory is that is a stress response in the brain to inspiratory flow limitation.
(and it is the PEM discussion that is being redirected elsewhere)
Yes, but there was kind of a general consensus to stop the UARS discussion too since people were not happy with the way I have the information on it currently organized, and so it was kind of agreed it was better to just come back to it when it was in a more accessible format to people. However, this will require a lot of work on my part, creating multiple sub-threads (or posts? can someone explain the difference between threads and posts on S4ME?), etc. I'm not sure that's how my time would be best spent at the moment, but I do plan to do it eventually...

I think what I have now is a decent overview and there's links to all the research (and my detailed Bluesky threads) for those who want to dig into it more.
 
Sorry, I think we're supposed to be keeping this thread inactive at the moment (so we can discuss this in DMs if you want), but how could you possibly know that "UARS presents quite differently to ME/CFS in terms

My understanding @nataliezzz was that you wanted time out from the thread to reformulate your proposition, rather than any consensus that the thread would be inactive while you did so. Given members have varying degrees of opportunity to participate in the site it would seem unfair to expect people not to comment here when able.

However if it is felt a thread needs to be paused or commenting suspended for whatever reason, normally moderators would close it to comments with a post indicating what is happening. That is something you could discuss with the moderators.

Perhaps something of a tangent (I must infuriate moderators trying to keep a thread on track), but -

I think it is an interesting question when reformulating ideas whether that is best done as a new post or posts or as a reedit of an initial post, my personal preference is that posts are not substantially rewritten after the fact unless there is misinformation, so we can see how ideas have developed through discussion and as it also may give rise to confusion given subsequent posts by others were responding to the original content that has subsequently disappeared. Further people following the thread may not realise the initial post has been rewritten given edits are not normally notified/flagged up. However others may think differently.

We tend only to replace whole posts when we are collectively drafting material for sharing externally as agreed S4ME communications or materials, such as our response to the consultation leading up to the new NICE ME/CFS guidelines or more recently our fact sheets. However that is not to preclude that there may be other good reasons for doing so.

There is also the option if material is substantially altered that a new thread is started, though it can get very confusing when two threads on the same topic are running in parallel (I suspect the moderators would not like that and would intervene, unless there was a clear reason for discussion to take place in a members only thread, but with more polished/edited material being placed in a public thread). This is probably something best discussed with moderators.
 
My understanding @nataliezzz was that you wanted time out from the thread to reformulate your proposition, rather than any consensus that the thread would be inactive while you did so. Given members have varying degrees of opportunity to participate in the site it would seem unfair to expect people not to comment here when able.
Ok, that's fine with me; I think what I have now is good enough to have a discussion (obviously just linking to the Bluesky thread was not). I would just ask people to at least read what I have put together in the OP (like I said, I think I've done a decent job with what's there now - it's enough to where people can develop a decent understanding of the theory and a few of the supporting studies, and if they want they can dig deeper with all the links I've provided. Eventually I can get around to creating multiple threads (posts?) with sub-topics but that just feels like a daunting project/perhaps not the best use of my time for now). But I would ask people to at least read what is there and try to understand it before commenting.

I'm still not sure I understand the difference between a thread and a post; could you explain that?
 
I'm still not sure I understand the difference between a thread and a post; could you explain that?
Each message here is a post.
This section that contains all of these posts and has the title «upper airway…» is a thread.
The thread is placed in a subforum called «possible causes …»
Which is in another subforum and so on
 
I’m running out of steam, so I’ll leave this be. I’ve tried to break down what you’re trying to say, but I don’t feel like I’m making any progress., so I’ll wait for you to get things sorted how you want it.
 
What I am writing now is a ‘post’. It may be confusing as on a blog what we call ‘posts’ (other than our initial posts) would be referred to as ‘comments’. So a ‘blog post’ approximately corresponds to our initial posts.

The thread is the whole collection of posts under a heading, in this case ‘Upper Airway Resistance Syndrome (UARS): a common underlying cause for all "chronic complex illnesses"? (ME/CFS, fibro, GWI, etc.)’

When, I think by @Trish, it was suggested you might want to consider creating some new threads, that was in relation to the specific studies you cited as supporting evidence, for example the Fibromyalgia study, so we could discuss the merits and implications of that study independently of any discussion of the idea that UARS has a causal role in a number of conditions.

I think this might help with establishing what we can say about sleep related breathing issues in the various conditions in separate threads, an important issue in its own right, then examine in more detail the proposed unifying theory in this thread. @nataliezzz, you are obviously deeply engrossed in all the detail which you want to share, but by presenting it all at once it becomes overwhelming and the thread becomes very difficult to follow as different issues are being discussed simultaneously.
 
Well, according to sleep doctors who diagnose UARS patients, they usually seek treatment for a "functional somatic syndrome" rather than sleep-disordered breathing or excessive daytime sleepiness before eventually being diagnosed with UARS: https://pubmed.ncbi.nlm.nih.gov/15510051/

And in the article I shared with you in the previous post it said "It is frequent that UARS is misinterpreted as chronic fatigue syndrome, fibromyalgia" (I'm proposing it's not misinterpreted but that it can cause them)

Here is the thing, I don't consider daytime sleepiness to be a core symptom of ME/CFS.

I have to sleep a lot (10-12 hours), but my usual symptoms are not daytime "tiredness"/"sleepiness", it's physical fatigue, brainfog, permanent headache etc. any orthostatic symptoms for me are only ever a symptom of PEM, not a day to day thing (my blood pressure is normal). We also know from studies that central fatigue is due to afferent feedback from type III/IV muscle afferents (this is a simplification because there is also spinal excitability to consider which can shift for individual motor units (leading to different activating thresholds) during fatiguing exercise, which also improves endurance) - because the signal can be blocked and when it is blocked it leads to an impairment in ventilatory responses to fatigue (this also overlaps somewhat with stimulation of certain autonomic afferent nerves too), and peripheral fatigue instead of central fatigue. If there is exessive stimulation of these afferents during PEM, then we would expect altered ventilatory responses during fatiguing exercise and that is exactly what we see with the 2 day CPET - we consistently see reduced workrate at the ventilatory threshold on the second day.

So the question would be, do we see this pattern in UARS patients?
 
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Here is the thing, I don't consider daytime sleepiness to be a core symptom of ME/CFS.

Me neither.

It doesn't tend to appear on patient-generated symptom lists, and you rarely hear people grumbling about sleepiness being a nuisance except after eating (which isn't specific to ME/CFS). If it were a common symptom people would probably talk about it more.

I'd love to be sleepy during the day, it would make the enforced rest a lot less boring if I could nap through parts of it. But I don't need any more sleep than I did before I got ME/CFS five decades ago, so I'm wide awake and bored out of my tiny mind.
 
I'm actually not trying to discuss it in relationship to the UARS theory at the moment. I'm just pointing out the fact that people continually say that PEM is unique to ME/CFS (which is just a name for a syndrome - a group of symptoms that tends to co-occur - after all; no one has confirmed that all ME/CFS is indeed one underlying disease process/disorder), so people should may want to stop doing that if it hasn't been proven to be true.

ETA: Perhaps better said, people should stop presuming ME/CFS is one disorder when this hasn't ben proven to be true (I'm aware that ME/CFS is the only disorder for which PEM appears in the diagnostic criteria, but ME/CFS hasn't been confirmed to be one underlying disorder).

It feels like you’re arguing against strawmen here. I don’t think it has been claimed in this thread that ME/CFS must be one disorder or that PEM is definitely unique to ME/CFS.

I know you’ll get a lot of unfounded statements on pretty much any other platforms, but those are not S4ME..

And I second Peter in that that discussion belongs elsewhere.

But to address another argument of yours:

That simply is not how you categorise health conditions. The presence or absence of PEM makes such a profound difference to the impact on the person’s health that to not distinguish between the different presentations makes no sense.

And biologically speaking, there has to be a distinct difference between someone with or without PEM, otherwise they would both have it or not have it. We don’t know what that difference is yet, but that isn’t relevant.
We can't assert who is with and who is without if we do not have a precise description of PEM and a description of symptoms is not an aetiology so those outside the description may nevertheless share the aetiology and presumably some of the symptomatic features (varying PEM features). For research purposes starting with an open mind and a carefully described closed cohort makes sense but it does not make good clinical sense if it risks throwing many out of the boat with no life jacket and a fair claim to having a form of PEM and possibly similar underlying biology to the closed researh cohort. As PeterT said this may belong elsewhere.
 
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Sorry, I think we're supposed to be keeping this thread inactive at the moment (so we can discuss this in DMs if you want), but how could you possibly know that "UARS presents quite differently to ME/CFS in terms of symptoms?" Only a sleep doctor who sees UARS patients on a regular basis could know that, and apparently sleep doctors who do, like the ones who wrote this article on UARS (Dr. Gold is not an author by the way), think that "tiredness/fatigue, fibromyalgia, headaches, insomnia, cold extremities, fainting, and low/normal BP" is how UARS patients often present. That sounds very similar to ME/CFS to me...
Such a doc would have to see CFS/ME without UARS too in order to tell the difference but if you are right the latter do not exist so a bit of a conumdrum (if I have understood rightly).
 
If you object to the idea We can't assert who is with and who is without if we do not have a precise description of PEM and a description of symptoms is not an aetiology so those outside the description may nevertheless sharee the aetiology and presumably some of the symptomatic features. For research purposes starting with an open mind and a carefully described closed cohort makes sense but it does not make good clinical sense if it risks throwing many out of the boat with no life jacket and a fair claim to having a form of PEM and possibly similar underlying biology to the closed reseacrh cohort. As PeterT said this may belong elsewhere.
I don’t follow. If you have a completely different clinical presentation (PEM vs no PEM), there have to be biological differences - otherwise they would have the same presentation.

Can you define what you mean by aetiology?
 
What is "completely different? How is "complete" difference defined?
You can arrive at no PEM by a specific description of PEM such that those who do not match that specific description do not have PEM even if they have a definite post exertional malaise. These cases will have biological differences from your described cohort, of course, but may have much in common. The commonalities may be more significant to overall pathology, research and treatment than the differences. Your line of argument tends to a conflation of a given descrobed PEM and ME/CFS rather than seeing PEM of whatever sort as a feature of ME/CFS. I do not think we are there yet and as I said your approach for research may be sound, but clinically is risky.
Significant aetiology may be shared among ME diagnosed with rather different presentations as to PEM.s and there is nothing to say that recoverers do not leave PEM behind. Of course it may be that recoverers never had the same form of PEM.
 
You can arrive at no PEM by a specific description of PEM such that those who do not match that specific description do not have PEM even if they have a definite post exertional malaise.
I don’t understand. PEM is just an abbreviation of post exertional malaise.
These cases will have biological differences from your described cohort, of course, but may have much in common. The commonalities may be more significant to overall pathology, research and treatment than the differences.
Can you give examples of conditions where this is the case? To me it seems like a case of something that could in theory be true, but in reality isn’t. But I might be wrong?
Your line of argument tends to a conflation of a given descrobed PEM and ME/CFS rather than seeing PEM of whatever sort as a feature of ME/CFS. I do not think we are there yet and as I said your approach for research may be sound, but clinically is risky.
Significant aetiology may be shared among ME diagnosed with rather different presentations as to PEM.s and there is nothing to say that recoverers do not leave PEM behind. Of course it may be that recoverers never had the same form of PEM.
I do not understand. «PEM of whatever sort» - what is that? And different kinds of PEM?
 
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