PEM discussion thread

It would be interesting to see what might be picked up on a 12 hr and 18 hr rpt CPET with controls or a 3 day rpt. Such tests might cast a light on this aspect of PEM and help determine if delay is obligatory, though shorter than a day for rpt may invalidate any controls if normal recovery and adaptation requires a day in even healthy patients.
I am concerned about the relatively recent claims that PEM must be delayed. It may be that delayed PEM is different from more immediate but (how) is this established? Is this about cohorting, which is a worthy aim, but "ME needs PEM and PEM needs to be delayed" goes well beyond cohorting and may leave many patients int the netherworld of MUPS, thrown out of the ME boat into the hands of whom? If PEM is observably delayed in the majority of patients with ME diagnosis then it is reasonable to hypothesise that the delay is related to the overall ME biology but it may be that patients with similar biology simply present PEM in another way. That happens in many conditions.
It is sensible where PEM may be exertion intolerance to carefully look for differentials but can we really at this stage do any more than make an assertion that PEM of ME MUST be delayed and if not the diagnosis is not ME? Symptomatically delayed PEM may accompany other conditions in a number of sufferers and with return to baseline marked by both reappearance of specific and non specific symptoms. Delayed PEM in ME may well describe a phenomenon which demands the definition of a certain patient group vs non delayed but there are dangers if it becomes a criteria absolute.

 

In my personal opinion (I might not be correct at all), we should say that it is reported that it can often be delayed.

So something like this (changes in red):

 

Is this approach helpful? With ME it may be we have multiple processes happening at the same time, and any individual aspects impact over laps with the impact of others. For example when I was still working and had not identified my food intolerances I had no idea what symptoms were related to sensory intolerances, food intolerances, orthostatic intolerances or PEM. It was only when it was possible to eliminate each aspect that any patterns became obvious.

Any identification of PEM may be complicated by these multiple processes happening at the same time, which also further may interact with each other:

• Ongoing ME symptoms which may include chronic fatigue
• More rapid than normal fatiguability which possibly is an exaggerated form of normal fatigue
• Specific symptoms, including orthostatic intolerance, sensory hypersensitivities that have modality specific effects which also increase general fatigue and if prolonged contribute to triggering PEM
• PEM which includes exacerbation of all the above and also paradoxical or atypical aspects

The atypical aspects of PEM may but don’t always include:

• Delayed onset
• Former ME symptoms not current reemerge or novel symptoms emerge
• Not necessarily improved by rest
  
• Continue to worsen after onset even with rest
• Lasts beyond what would be expected with normal fatigue or normal effects of over exertion, from days, weeks to months, years to indefinitely
• Evolution of symptoms over course of individual episodes
• ?

Assuming the increased fatiguability, increased OI and hypersensitivities are independent of PEM though interacting features, with any one episode of worsening symptoms it might not always be clear what is PEM and what is not. Given this overlap and confusion it may be that we can only conclude that any specific episode is unambiguously PEM when one or more of the atypical or paradoxical aspects are present. That is not to say anyone not experiencing some or any these features does not experience PEM but that it is hard to be certain.

[edited to add first paragraph]

 

To add to the mix is that some of us don't experience many or noticeable ME/CFS symptoms, and delayed PEM feels like a whole different illness. When I didn't have OI or cognitive issues for 11 years after onset and was feeling 90% improved, I still experienced the same horrible delayed PEM that I experience now 20 years later.

 

Good point, I’ve heard of that from other people as well. Is it covered by ‘expanding of symptoms’?

 

I was diagnosed with "atypical ME" 32 years ago by an ME expert. He did not think I had ME from his 25 years of experience. I had what was described as PVFS for several years. I didn't experience delayed PEM for years after onset, even after exercising, my leg muscles just felt exhausted.

I felt 'bad' after going for a 50 minute walk with leg muscle fatigue/exhaustion the next day for weeks when I got Covid a couple of years ago. I eventually recovered from post-Covid 6 months later and went back to baseline ME. I don't even tell my GP this so that I don't confuse my situation b/c she might think I'm totally recovered from ME too.

 

Hopefully we can move away from the term ME when they figure out the pathophysiology of delayed PEM.

 

Yeah, maybe the only thing we can say is that it's a delayed reaction, and in people who've lived ME/CFS for some time, it's often a predictable delayed reaction.

The same goes for food intolerances, but with experience the symptoms are probably distinguishable by individuals.

I wonder if there's anything we could say about consistency, given that there's probably little or no research? My "acute illness" pattern probably doesn't occur in everyone, but for me it's been present for five decades. Most of the symptoms have been very consistent, all that changes is the severity and duration.

 

Some quick thoughts having only glanced. For me, delayed PEM was so much more transparent when in my severer levels because I was experiencing it over and over for years. So it was clearly experienced.

At my moderate level now I don't get that delayed PEM intensity anymore. I still get ME symptoms but I am at a stage where my pacing is enough to not trigger severe symptoms because I am now able to keep within my limits. Whereas in my severer levels just holding a book or moving a heavy chair would worsen my ME and set off the delayed PEM. It felt like a lot of layering and rolling PEM and delayed PEM in those years. It was the full works, full on.

To hold on to this moderate level now I know I have to be careful of accumulation exertion over a period of time because from past experience this will give me a bout of severe delayed PEM which would send me back to the severer years if I continued to overdo in this way.

I still feel my cognitive difficulties and the need to lie down are still great, along with some other symptoms. But I remember my early ME was like this before I deteriorated to very severe ME.

 

This is something I've been thinking about. I still get PEM occasionally, especially in the Spring, after jogging 4x150m. But it usually lasts half a day and I'm back up on my feet by the evening the next day. I still call it a PEM, but it certainly does not resemble PEM that an average ME/CFS patients experience. On the other end, it takes 4 days for me to recover from 4 hours of skiing. I call it a longer-than-usual recovery, not PEM.

PEM seems to slowly become indistinguishable with normal recovery as I improve. If it is a spectrum, like ME/CFS itself, there should be a line to distinguish the pathological PEM from worse-than-usual recovery. Otherwise "PEM" could become clinically meaningless.

That is not to say that short PEMs or worse-than-usual recoveries are not disruptive. They are. That is why I hung up my skis and jogging shoes at the end of January. But I still think it is a good idea to define PEM as the ones typical to typical ME/CFS patients for clinical purpose, rather than every "worsening of symptoms after exertion".

 

I agree with this. PEM is so much more discernable in the severer levels.

Patients with early ME should be given symptom lists like, unusual exhaustion, needing to lie down, feeling very ill, fluish like symptoms etc. OI could be present also, so a symptom list for this.

 

My intention was not to include everybody but rather to say given our current understanding it is hard to know what to include or exclude so for the time being we should only use the term PEM for the atypical/paradoxical features whilst acknowledging that this may exclude some who when our understanding improves may turn out to actually also have PEM.

 

I don't know where to ask or to look for it but I was wondering if there's a list of treatments that people use to help with PEM? Either to avoid it, to increase threshold, to increase rate of recovery, reduce symptoms etc?

 

A few people have found things that help with PEM, but they're so individual that they don't usually make much difference to others. If you're not severely ill you can avoid some of it by staying under your threshold, but once you've crossed that, it's like an acute infection or an alcohol hangover. Nothing to do but grimace, roll your eyes, and sit it out.

I'm not sure it's feasible to increase your threshold or speed up your rate of recovery—if it were, it would mean we had a treatment. ME/CFS might occasionally give people the impression they can control it, but in five decades I haven't come across many who convincingly can. It fluctuates, it goes through periods of stability, and because in some people those phases last many years, it can give them the impression of control. I've thought I was in charge more than once, but the truth is it was always an illusion.

 

It's very subjective, that's definitely true. I'm sure it also depends on the baseline one has. I'm mild, so my anecdotes will have nothing in common with moderate or severe patients.

What seems to help me with my threshold and recovery is dextromethorphan. I've managed to go on some easy treks (1h, not more than 100 m altitude difference) without PEM on multiple occasions if I took dextromethorphan before. The same treks lead to PEM when I didn't take it. Could surely also be daily fluctuations in energy and unrelated to DXM. I found out about it through a presentation by Bateman Horne a couple years back. Not sure if they still recommend/use it.

Would it not still be interesting to have a summary on what seems to help some people, even if it is quite individual? Might lead to somebody trying something that seems to help - if it's not just an illusion, as you say. Not sure how much placebo can help in the long run.
With a hangover some pain killers might help for some symptoms right, it won't cure the hangover but make it more manageable.


Thanks to both for your insights!

 

I would see it a bit more nuanced, but fair enough.