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

I consider myself challenged then.

If that were true then why would pacing be so important? I have nothing like what you suggest - if I let myself then I would have numerous initiated tasks that I would then not complete, due to what I can only describe as a lack of energy, however technically accurate that might or might not be.

 

Maybe a division can be made between PEM with explanations along your lines and other exertion intolerance where such things as muscle probs from aberrant protein, low o2 uptake may be part of the mechanistic picture. As stressors they may contribute

What about the question of what is benign controlled ?. I'm thinking of e.g the aberrant muscle protein or C Thomas low oxygen uptake . It may be the accounting system is wrong but that there are perhaps abnormalities that need accounting for which strain and corrupt the system.

 

Andy, you seem to be conflating the situation where you feel reasonably 'energy replete' when you might have taken on a task but know not to because of learning to pace and the situation of having done the task, feeling 'energy depleted' and at that stage having an overwhelming sense of not being able to initiate anything further.

Surely the symptom of energy depletion is the second situation. Pacing is designed to steer away from it.

 

When I say a control system I am talking about control of the capacity to execute tasks. Lots of control systems may affect that - cardiovascular regulation, which fails in heat failure, sugar regulation which fails in some (rare) endocrine conditions, central nervous regulation as in Parkinson's, acid base regulation in kidney disease etc. For most of these except CNS we ought to have been able to measure some abnormalities, at least in severe cases, and so far we haven't.

I am not sure what C Thomas low oxygen uptake is.

I think that you are suggesting that there might be some failure of muscle cell metabolism such that however much the control system works there is a limit on capacity for activity. From everything I have seen so far this seems to me unlikely. People with ME who are doing quite well suddenly relapse badly and I don't see how that is easily explained with some continuing defect of muscle metabolism. Most muscle pathologies are to some degree regional - distal or proximal or something like that. As a result people develop trick movements to take advantage of the less affected muscles - and may get patterns of atrophy and hypertrophy. I don't see any evidence for that in ME.

What would make sense would be some genetic variation that made muscle more susceptible to a control system failure through cytokine signalling in response to activity or something like that.

 

No, I'm not conflating anything. I feel a sense of energy depletion all the time - and this gets worse the more I do, up to a point where I don't feel the ability to initiate anything else. Sorry if that doesn't make scientific sense but that is how it is for me, and I believe many other people as well.

 

OK then I would say you aren't on autopilot anymore because the need to exert to keep showering has kicked in right away! Although I actually think the previous version was better.

 

I understand that Andy, but you did say that if it wasn't for self-discipline through pacing that you would go off and do things and then regret it later.

As for what Trish says, it all makes sense as a starting point for scientific modelling but I am just wary of using the term energy depletion when even in colloquial terms it looks as if it has more than one meaning.

 

Would malaise work better for you? As a scientific term?

 

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.

 

So what should we use then? What terminology would be 'acceptable' to researchers? It seems to me that, as per usual, pwME, who after all also have to deal with cognitive issues, are in a bind where we use the words available to us to describe our experience but because the words we use don't fit current scientific understanding we get, at best, criticised for using the 'wrong' words, or at worse dismissed as unreliable witnesses. Frankly I'm fed up with it.

 

Thanks for the clarification though I am not sure I have understood and I am surprised that nothing has been found over such a range of systems. Thomas found low o2 uptake in PMNBC's at Newcastle in an ME cohort. I have read one article from Bath (I think) where a disorder of proprioception was treated and relieved ME symptomology (or what was labelled as ME).
There are imo a variety of scenarios.

 

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.

 

Could be both. Engine problems, pilot keeps flying, enginen gets worse (potentially), pilot gets tired/overwrought. Two systems one flight experience.

 

Do you think, even for a moment, that malaise is any less onerous and injurious to the patient community than fatigue? Any less colloquial and laden with cultural baggage?

And malaise is not?

If you are searching for science speak, you'll not find it there. Science may be able to rise above culture, but it has been my experience of well over 25 years that most physicians cannot.

 

It is nothing to do with not fitting scientific understanding or being the 'wrong' words, Andy. It is simply a matter of being unambiguous in conveying subjective symptoms to someone trying to work out what to look for to explain them. As I said before, very often when trying to make a diagnosis it helps to ask patients to forget any words they think people would often use in a context and use 'their own words' in the sense of anything you like that might help someone who cannot actually experience it. But preferably words that do not involve a hidden metaphor like energy depletion does. It assumes some sort of explanation - that there is some stuff that is at a low level.

For rheumatoid disease there is a symptom called early morning stiffness that is a bit like PEM for ME. But I would never want patients to learn to say 'I had a lot of EMS this week.' Unfortunately there are people called 'patient partners' who get taught to teach doctors how they have 'EMS'. In reality every person is different and at every clinic session I would be interested in something different about the symptom pattern, in the context of what we were trying to achieve with treatment. Nobody ever needed to define EMS in detail - the term just flags up a range of problems that are important for management.

 

I have absolutely no interest in whether or not it is seen as onerous. I am purely interested in trying to help people research the cause so that PWME can get some treatment.

I see no evidence that the BPS people have taken malaise to be psychologisable in this context. Most of them try to deny it even exists. I am pretty sure that the term PEM was invented by people who understood malaise the way I do and that medical professions as a whole do the same.