Post-Exertional Malaise - a discussion including defining and measuring PEM

[chillier]

And maybe I am saying that we should not think it is likely to be either. It is the circuitry in the cockpit electronics that makes the pilot rightly sense the plane is un-flyable even though the fuel tanks are full and the engines ticking over.

It is like my new gas boiler. It stopped working. It was under guarantee. We wanted it sorted and rang the people who fitted it. They suggested getting on to the boiler company to check if the problem was under the guarantee. But the guarantee was only valid if we had had the boiler serviced. So we went back to the fitters to ask for a service. The boiler was fine that day. So we got our service box ticked and had a working boiler. But the next day the boiler didn't work. The coming Monday it did work and the fitting people said there was no point in looking at it again if it was working. Especially as I had tried every possible combination of turning things on and off to see what tripped the problem and got no sensible answer whatsoever. So we had a boiler that was totally unreliable for reasons that made no sense and probably were not under the guarantee that now was valid because ewe had had a service.

Fortunately after a fortnight the boiler stopped not working and has been fine since.

Having had two recent bouts of post-viral (Covid) fatigue I am pretty certain that this sort of model applies there. The body has all the right equipment to run for a bus but trying to change a lightbulb leaves me lying on the sofa feeling sick and exhausted. At the moment our understanding of neuroimmune connections does not provide any obvious explanation for the longer term ME situation and nobody can find anything wrong, but I am sure there is.

When you say energy you are referring to molecular explanations of energy is that right? i.e mitochondria, ATP and so on. As opposed to energy in the sense of a symptom like being fatigued? The latter usage seems fair enough to me in a clinical context it's the most straight forward way to explain what we're experiencing as patients.

I'm trying to understand what you mean by entropy in this context. To me these examples such as travelling are strenuous and tiring because they involve constant vigilance, checking the traffic or making sure you make the train connection. This to me is stress, and I don't know what that necessarily means on a molecular level, wether that means cell damage and repair and forming new synapses etc (like needing to do the washing up before the sink is ready to use again)? Is this the disorder you're talking about?

Your other analogy sounded like it was about doing things on autopilot - learned versus unlearned ability. For example I know how to speak english, and when I'm not too tired I understand it not only without effort, but i couldn't not understand it if I tried. If everything was in German it would be constant stress and effort trying to understand - I can speak German to a degree but it has not become intuitive knowledge and has to be recalled with effort. Are you in a way suggesting that basic activities like brushing your teeth become stressful activity as if you didn't intuitively know how to do them?

 

[richie]

Malaise works for me on a very simple basis - that PWME do not feel tired, they feel ill. And that situation is familiar to me and most people having had flu (the malaise paradigm) and trying to do things resulting in feeling terrible. That does not make me equate the two but just the basic idea that PEM is not tiredness was crucial to my getting some idea of what it might men.

And it seems that even the colloquial use of 'energy' is confusing. 'I don't have the energy' is used for something that we recognise can be reversed in an instant. It can also be used for something that you can do nothing about if bombs are dropping. So it is very open to a BPS reading.

There is no categorical tiredness vs illness dichotomy. What about pathological tiredness? Depression is not the same as sadness but malignant or pathological sadness expresses sth. So does malignant or pathological fatigue. It's just different from ME PEM And the diagnosis of ME has been such that many have such fatigue as their key symptom with a post exertional element but do not feel the same setbacks as those with serious PEM. I have had flu once and did not even feel ill. Just knockout, knock down fatigue -pathological fatigue/tiredness.

 

[Jonathan Edwards]

The latter usage seems fair enough to me in a clinical context it's the most straight forward way to explain what we're experiencing as patients.

My point is that it is fine as somewhere to start but can very easily be ambiguous, as the discussion seems to confirm. Even in plain language it is used to mean different things. If the idea is to define terms in a way that helps doctors and researchers solve the problem then I see energy as troublesome. I think there are lots of researchers who translate it into looking for metabolic blocks in muscle for instance and I don't think that is necessarily valid.

I would forget about entropy. It is something that comes up in the context of free energy. It is in a sense unusable energy and is irrelevant to our discussion.

I thin the problem with telling is that it is hard mental work. That is not necessarily stress, although it may be stressful. I think there may be a limit to how much our brains can cope with the constant usage of short term memory - hence the need for sleep. Mechanisms like that might be impacted in ME.

 

[duncan]

I cannot speak for the UK or any other part of the world for that matter, but I feel fairly comfortable predicting that in much of the US, if a patient walked into a clinic and pronounced "I am suffering from malaise" to most any medical professional, they'd likely be put on SSRIs or referred to a psych.

 

[Jonathan Edwards]

There is not categorical tiredness vs illness dichotomy.

No but the point PWME make is that PEM is not just tiredness.
There may be pathological tiredness but this is not what people tell me is the problem - or not the only problem.

I am familiar with extreme tiredness after a 36 hr unbroken period of duty as a junior doctor. I am also familiar with a kyboshing state during viral illness and after when doing things illicits nausea, brow sweatiness and faintness as well as exhaustion. From what PWME say it seems that PEM has features in cmmm with that. I had none of those after 36 hours on duty - I just wanted to get to bed.

 

[Jonathan Edwards]

in much of the US, if a patient walked into a clinic and pronounced "I am suffering from malaise" to most any medical professional, they'd likely be put on SSRIs or referred to a psych.

Yes of course they would, just as if a patient walked into my clinic and said 'I am suffering from early morning stiffness' eyes would roll (and some might snigger). Medical terms are not supposed to be what the patient says in their complaint. They are terms of art deliberately outside normal usage that are useful for doctors to build their diagnostic processes around. If someone came to an ME clinic and said 'I have this awful post-exertional malaise' I would immediately wonder what websites they had been trawling and ask them to explain what on earth they meant by that.

 

[duncan]

They are terms of art deliberately outside normal usage that are useful for doctors

Terms of art? Cool!

 

[Kitty]

Some part of my back brain understands what you're saying, @Jonathan Edwards. The front bit is AWOL today, so I can't respond except to say it's interesting and it hadn't occurred to me before.

I think I also understand what you're getting at about the use of language and imagery. It can constrain understanding as well as communication, so it's really good to see it being dug into.

if a patient walked into a clinic and pronounced "I am suffering from malaise" to most any medical professional, they'd likely be put on SSRIs or referred to a psych

A doctor told me I was had malaise when I was 17. I asked him what it meant, and I thought it summed it up much better than I had in several appointments' worth of incoherent rambling. I'd never use it myself either, but I've no problem with the medical usage if it's done straightforwardly.

 

[duncan]

A doctor told me I was had malaise when I was 17. I asked him what it meant, and I thought it summed it up much better than I had in several appointments' worth of incoherent rambling. I'd never use it myself either, but I've no problem with the medical usage if it's done straightforwardly.

A doctor told me I had CFS and forbade me from having any labs done. His office staff always referred to my fatigue and tiredness, as did he - although I never used the word tired to describe how I felt.He put me on an SSRI.

Doctors, and yes, researchers, misuse their own language. It can be a crutch. They should rarely imo prefer the vague over the specific. They often do, though. I suppose it's easier on them. But if misunderstandings emerge from this pig-latin of sorts, it's the patient community that pays. For decades now we've struggled to clarify, to refine descriptors, to parse down on our diseases's characterization in an effort to help science help us. Doing anything to obscure accuracy and the progress we've struggled for, worries me.

 

[richie]

Exercise alters brain activation in Gulf War Illness and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome | Brain Communications | Oxford Academic (oup.com)

Probably been posted before. Point for me is serious does not mean the same.

 

[richie]

A doctor told me I had CFS and forbade me from having any labs done. His office staff always referred to my fatigue and tiredness, as did he - although I never used the word tired to describe how I felt.He put me on an SSRI.

Doctors, and yes, researchers, misuse their own language. It can be a crutch. They should rarely imo prefer the vague over the specific. They often do, though. I suppose it's easier on them. But if misunderstandings emerge from this pig-latin of sorts, it's the patient community that pays. For decades now we've struggled to clarify, to refine descriptors, to parse down on our diseases's characterization in an effort to help science help us. Doing anything to obscure accuracy and the progress we've struggled for, worries me.

No but the point PWME make is that PEM is not just tiredness.
There may be pathological tiredness but this is not what people tell me is the problem - or not the only problem.

I am familiar with extreme tiredness after a 36 hr unbroken period of duty as a junior doctor. I am also familiar with a kyboshing state during viral illness and after when doing things illicits nausea, brow sweatiness and faintness as well as exhaustion. From what PWME say it seems that PEM has features in cmmm with that. I had none of those after 36 hours on duty - I just wanted to get to bed.

Agreed re. what the reported problem is but you did veer imo into an implication that fatigue is not in itself pathological, when it may be. When I had flu I just flaked out and slept. I do not recall it as much different form extreme exhaustion. Tired legs is a specific symptom of my illness. It is not imo different from immediate post running feeling that I had in youth but in the illness contest is imo pathology. My legs don't "feel ill" or make me "feel ill" but it is a pathological fatigue.
My Mum as a nurse never got flu when all around were flaking out. That meant shifts on end and massive fatigue. But the fatigue may have in fact been not just the long hours without break but her expression of flu or indeed whatever virus, since no other viruses seemed to get her as they got others.

I understand the probs with the term malaise but I see that pragmatically and sensibly handled by doctors it may for now be the best option. However in promoting the integrity and validity/reality of the concept and term, I feel that other forms of serious disabling post activity phenomena may eg dismissed whether they be pathological fatigue, sarcoid post exertional phenomena or indeed other things. One of the main objections to CFS is that "fatigue" makes things sound trivial and that is the objection to "malaise" too. I support a position which promote the idea of medical (pathological) malaise and medical (pathological) fatigue as different (though overlapping), but both valid

 

[Kitty]

For decades now we've struggled to clarify, to refine descriptors, to parse down on our diseases's characterization in an effort to help science help us.

But those descriptors might help, or they might send them down rabbit holes, or they might give the bad faith type ammunition. Exactly as the pig-Latin can.

The trouble with language is that it's catching. Someone comes up with an image, and before we know it we've woven it into the story and it's become the accepted version. Familiarity makes it a sort of fact. It affects scientists as well as patients, because we're all stuck with using symbols for things. It's not a bad idea to take a look at the choice of symbols, and how we tell the story.

In a safe space, obviously. In the outside world, I imagine I'd share your suspicions entirely.

 

[duncan]

I support a position which promote the idea of medical (pathological) malaise and medical (pathological) fatigue as different (though overlapping), but both valid

I hear you. Alternatively, there are people like me who view both their use in medicine as lazy.

But those descriptors might help, or they might send them down rabbit holes, or they might give the bad faith type ammunition. Exactly as the pig-Latin can.

The trouble with language is that it's catching. Someone comes up with an image, and before we know it we've woven it into the story and it's become the accepted version. Familiarity makes it a sort of fact. It affects scientists as well as patients, because we're all stuck with using symbols for things. It's not a bad idea to take a look at the choice of symbols, and how we tell the story.

Yes. This is even more of a dilemma, for lack of a better word, where contested diseases are involved, and where inertia, indifference and even hostility characterize the better part on the medical community's attitude and response.

 

[richie]

I hear you. Alternatively, there are people like me who view both their use in medicine as lazy.

The paper on GWS uses "dysfunction", but the specific nature of ME PEM is not maintained in that term. Hard to know what else to use than malaise etc.

 

[Hutan]

This is basically the argument Mike Murphy made at the IiME conference around 2015. A failure of actual energy availability as in ATP would give a very different picture from ME it seemed to him, and to me. If PWME ran out of brain energy they would black out lying down. They don't.

Someone close to me has recently suffered from a stroke that has affected their language ability. This person now has to work hard to read simple words, one at a time. And he can only do that for a while before feeling exhausted. When rested, he can write a few sentences for a thank you note as a draft perfectly, but the effort of doing that seems to be exhausting. He can't then immediately repeat those sentences on the actual thank you card, he can't even form the letters. There is capacity for a very short time, and then there is not. He has not run out of energy globally - he can still speak and walk. Do we know what causes this?

Is the situation in stroke and with us consistent with the idea of neurons firing but not being able to reset to fire again quickly enough? In the case of stroke, could it be due to whatever chemicals are around from the brain damage?

I think we have seen a few clues suggesting that there are problems in ME/CFS and similar illnesses with ion channels, with the speed of neurons to be able to re-fire.

 

[Jonathan Edwards]

He can't then immediately repeat those sentences on the actual thank you card, he can't even form the letters. There is capacity for a very short time, and then there is not. He has not run out of energy globally - he can still speak and walk. Do we know what causes this?

Each case is different and we don't have detailed explanations but we have a reasonably good idea of the problem. With both stroke and dementia different parts of the brain lose their normal interconnections and the result seems often to be a bit like a permanent bad dream where you are trying to open the locked attic door thinking it is the loo.

My father in law had a big stroke affecting his right cortex so that he could not sense his left side but could speak fluently (left cortex). He had what is known as agnosia. He could walk with both legs but could neither see, nor think, about what was to the left or how to get there. Yet at a higher level, since both of us were trained to recognise this problem, he realised that he had agnosia and that he was unable to think about the left. He solved this by going round in circles to the right, on the clever deduction that this would get him to the left. His legs were perfectly capable of turning him left but his mental picture had no left in it to want to go to, only his verbal intelligence covered that.

The situation was initially almost amusing to him but over a period of days it became more and more exhausting and frightening for him. To the extent that when we took him in the car to see his favourite boatyard he kept his eyes shut the whole time because he could not cope with the effort of trying to get out of the bad dream.

And all that makes perfect sense in terms of the way we understand zonal brain function. If words are hard work it is because Broca's and Wernicke's areas in the left cortex are not talking to each other easily. Over time lucky people find ways of telling themselves what they want to say by tricks. And weak connections get beefed up and eventually they may talk well. My wife had some of this after her ECT. My mother just has a few islands of function connected through indirect routes. She does not recognise me at all but ten minutes later asks me a question that shows some other part of her brain knows very well that I am there. 'Where's your knife and fork, Jo?' when we are served lunch together in her room.

 

[Jonathan Edwards]

I don't think PWME have cortical problems much. I think the main problem is much lower down, where the hypothalamus talks to the body. But I would not discount marginal effects on visual responses and things.

I think a stroke for the CNS is a bit like a leukaemia invading bone marrow for the immune system - there is a big hole and things try to work around it. I see ME as likely being much more like an autoimmune disease in which the signalling control system has got reset wrongly or is continually being thrown off target by some other control system - which would most likely be the immune system too because it is something complex and subtle.

 

[Hutan]

I think I'm not talking about the absolute loss of function in a stroke (that arising from the "hole" in the brain), some of which can be ameliorated by finding different ways of doing things. Instead I'm talking about how some tasks can be achieved, but not repeatedly. What is the process of that mental exhaustion?

 

[Jonathan Edwards]

Instead I'm talking about how some tasks can be achieved, but not repeatedly. What is the process of that mental exhaustion?

OK. So that is a completely unanswered question. I d not think anyone has the beginning of a clue. Most difficult mental tasks rapidly get easier on repeating.

If I were to scrape around for suggestions I think I would wonder if it is a signal that says 'no not again it is just too awful'. Like when you are trying to teach a child to ride a bike, which is essentially a mental control activity, and after a few failed attempts they say 'no daddy I don't want to'. The sense of failure washes over even a partial success and it is best left for another sunny day.

And if you read Michael Gazzaniga's accounts of people who had their cortex cut into two halves fr intractable epilepsy you will discover that a poorly connected brain will tell you things about its thoughts that cannot really be true, other than perhaps at a rationalised superficial level.

 

[AliceLily]

No but the point PWME make is that PEM is not just tiredness.

Yes, PEM has exhaustion/fatigue/weakness, but it is one part of many significant symptoms which malaise covers. That's why I don't like the use of PEF being used on it's own.