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Is PEM a crash? Is a crash PEM? Semantically distinct? Or distinct phenomena?

leokitten

Senior Member
Messages
1,542
Location
U.S.
My question really is about the semantics of 'crash' and 'PEM'. I guess I used to use both these words somewhat interchangeably and wanted to ask PRers what they think.

In my experience with ME, PEM, or a worsening of symptoms, happens after mental or physical overexertion. When I have too many periods overexertion over a short enough length of time without sufficient rest (or a continually long overexertion) then the PEM continues to build until I have a crash. Rarely too I've had crashes that seem to have come out of nowhere and didn't appear to be preceded by PEM.

So these words are distinct but related phenomena to me. What do you think? :nerd:
 
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Wishful

Senior Member
Messages
5,684
Location
Alberta
One problem is that there isn't one clear, concise definition of PEM. I get PEM 24 hrs after activity that strains muscles unusually. I also get PEM-like symptoms within a few hours of certain cognitive activities, such as driving or socializing, and the symptoms and magnitudes are somewhat different from the ones from physically-induced PEM. So, two different types of PEM, or is one of them not actually PEM?

For me, I prefer to refer to my consistent physically-induced symptoms as PEM, and the cognitive ones as PEM-like. I'd use the word 'crash' for a serious and lengthy increase in symptoms that doesn't fit into the other categories.
 

Seven7

Seven
Messages
3,444
Location
USA
Great question here is my definition
PEM= exarcebation of symptoms ( could be energy affected also but not necessarily) so muscle pain, sleep worst, fluish... temporary, body saying stop.

Crash= I hit a wall and my energy base is lower than my normal. Even if symptoms Recide, the energy level has not gone to my normal base.
 

ljimbo423

Senior Member
Messages
4,705
Location
United States, New Hampshire
My question really is about the semantics of 'crash' and 'PEM'. I guess I used to use both these words somewhat interchangeably and wanted to ask PRers what they think.

In my experience with ME, PEM, or a worsening of symptoms, happens after mental or physical overexertion. When I have too many periods overexertion over a short enough length of time without sufficient rest (or a continually long overexertion) then the PEM continues to build until I have a crash. Rarely too I've had crashes that seem to have come out of nowhere and didn't appear to be preceded by PEM.

So these words are distinct but related phenomena to me. What do you think? :nerd:

I agree. I have PEM that always hits me 2 days after too much physical exertion and always lasts 24 hours and is mostly just an increase in fatigue with a mild headache.

I also have crashes or flares, where I feel just like I have a cold or the flu, which are much worse than PEM. These flares now last about 2 days and can happen almost anytime.

My flares, not PEM, use to last 7-10 days. Slowly they have gone from 7-10 days, to 5-7, then 4-5 and now only last 2. So I seem to be moving in the right direction!:)

I can't help but wonder if the PEM is caused by mitochondrial dysfunction in the body and the flu-like flares I get are caused by the microglia in the brain being activated by the immune system or by mitochondrial dysfunction.

The flu-like flares suggest to me that the brain is being affected. Just as if I had a real flu.
 

leokitten

Senior Member
Messages
1,542
Location
U.S.
I can't help but wonder if the PEM is caused by mitochondrial dysfunction in the body and the flu-like flares I get are caused by the microglia in the brain being activated by the immune system or by mitochondrial dysfunction.

++ to that theory, that this disease is immune and cellular energy dysfunction each feeding back on the other... which came first, chicken or egg, I don't know! ;)
 

Wishful

Senior Member
Messages
5,684
Location
Alberta
I haven't been able to find a clear verification in scientific papers, but I think many of the flu-like symptoms are due to excess kynurenines, particularly quinolinic acid. That's made in the brain (doesn't cross the BBB easily) by activated microglial cells. My guess is that the immune system triggers this, and mitochondrial dysfunction is part of the feedback loop, but maybe the mito dysfunction makes the immune system more sensitive...

Do chickens get ME/CFS? :)
 

Learner1

Senior Member
Messages
6,305
Location
Pacific Northwest

perrier

Senior Member
Messages
1,254
Has there been any scientist who has indicated what causes PEM.

This signature symptom is with many people around the clock, though it can go up and down depending on what exertion took place. Some folks get PEM from just going to the loo.

I tried to get a description of it. Our family member says it most resembles ( though not quite) what she experienced when she had to get a number of vaccinations to travel east. She said after the vaccinations she felt awfully sick, and says that this is the closest she can compare PEM to.

I am bewildered how some folks get rid of it. Our family member has never had one second without it: just degrees of intensity occur.

What are the scientists saying about it?

I must say that this symptoms I have had the most difficulty describing even to cfs doctors! Crash they understood, but this PEM was difficult.
 
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Wishful

Senior Member
Messages
5,684
Location
Alberta
I think there are different types of PEM. One type has an immediate response. One has a consistently delayed, such as 24 hrs, response. My cerebrally-induced PEM, which has an inconsistent few-hours delay, has somewhat different symptoms than from physically-induced PEM which has a consistent 24-hr delay. That's just the different types I'm aware of; there are likely others.

My guess is that PEM symptoms involves immune response chemicals, which is why they feel similar to viral infections. Actually, I think kynurenines (released due to IFN-g) are responsible for at least some of the symptoms.

For me, a level tsp of cumin (the spice used in curry) completely blocks my physically-induced PEM for three days. Unfortunately, no one else has reported that it works for them. It doesn't block my cerebrally-induced PEM.
 

ljimbo423

Senior Member
Messages
4,705
Location
United States, New Hampshire
Has there been any scientist who has indicated what causes PEM.

This is what Fluge and Mella say in this paper-

Impairment in PDH (pyruvate dehydrogenase) function could therefore be consistent with the reduction in aerobic threshold, poor recovery, and postexertional malaise as observed in ME/CFS patients.

Such a mechanism would be in agreement with the observed difference in workload intolerance versus disease severity among ME/CFS patients, by relating symptoms to the magnitude of metabolic obstruction.

It sounds like they are saying it's the degree of mitochondrial dysfunction that determines PEM.

This is what Chris Armstrong posted here at Phoenix Rising-

Well we all experience a bacteremia when we exercise. The type of bacteria that enter your bloodstream are usually quite controllable by your immune system but if your gut is further

compromised they may release more bacteria into your blood or more pathogenic species or your immune system may already be depleted. This is the concept for the chronic sepsis or SIRS and this is what I think may be behind PEM.

I don't know of any other researchers or scientists theory of PEM. Maybe somebody else does?
 
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perrier

Senior Member
Messages
1,254
This is what Fluge and Mella say in this paper-



It sounds like they are saying it's the degree of mitochondrial dysfunction that determines PEM.

This is what Chris Armstrong posted here at Phoenix Rising-



I don't know of any other researchers or scientists theory of PEM. Maybe somebody else does?
Then right there we have two causes: 1) impairment in PDH function and 2) immune system impairment of some sort coupled with gut impairment

So, we aren’t sure which it is, or both. So we don’t know then for sure what is causing it, this signature horrific symptom PEM.

How can folks be helped to get rid of it when we aren’t sure where to focus. The severely ill have this horror non stop.
 

ljimbo423

Senior Member
Messages
4,705
Location
United States, New Hampshire
So we don’t know then for sure what is causing it, this signature horrific symptom PEM.

How can folks be helped to get rid of it when we aren’t sure where to focus.

I really don't know. It took me 8-9 years to convince myself of what I believe is causing my ME/CFS. That's averaging about 30 hours a week of researching.

My biggest problem for those 8-9 years was not knowing what to treat or what to focus on, like you said.

I treated possible viral infections, mitochondrial dysfunction, adrenal fatigue (which I now think is really HPA axis dysfunction), poor methylation, etc.

With very little sustained improvement, until I became convinced of what I now believe is the cause of my ME/CFS. Even then, it took me 2 years to learn how to somewhat effectively treat it and it's still slow going.

As a caregiver I can't imagine the burden you feel. I wish I had better answers.
 

perrier

Senior Member
Messages
1,254
I really don't know. It took me 8-9 years to convince myself of what I believe is causing my ME/CFS. That's averaging about 30 hours a week of researching.

My biggest problem for those 8-9 years was not knowing what to treat or what to focus on, like you said.

I treated possible viral infections, mitochondrial dysfunction, adrenal fatigue (which I now think is really HPA axis dysfunction), poor methylation, etc.

With very little sustained improvement, until I became convinced of what I now believe is the cause of my ME/CFS. Even then, it took me 2 years to learn how to somewhat effectively treat it and it's still slow going.

As a caregiver I can't imagine the burden you feel. I wish I had better answers.
Dear Jim,
Look at all the directions you went into it. All patients do this, and I wonder if they have hurt themselves from all the various drugs they have been given to try. Our family member tried it all, but to no avail. And is now trying to lower these drugs which have not helped.
 

Wishful

Senior Member
Messages
5,684
Location
Alberta
My favourite hypothesis for what causes my physically-induced PEM is the increase in IFN-g 24-hrs following the activity. The IFN-g triggers an increase in IDO, which catalyzes more TRP into nasty kynurenines. Viral infections, which also increase IFN-g, cause what seems an identical increase in symptoms as my PEM. My observations fit this hypothesis, and I haven't found any counterevidence.

I don't have a hypothesis for the cerebrally-induced PEM.
 

*GG*

senior member
Messages
6,389
Location
Concord, NH
Want to respond, as a very long time member, practically founding days, great questions!

I don't think a crash and PEM compare, so it's not semantics for the sufferer, but to move on.

Not sure where you live, but if you can do it, look into the 2 day CPET test to see where you are at!

Sorry, been a long day, somethings not clear, I will try to clarify.

Willing to share my data from 2 Day CPET, so if you want, I post and will send it to you. Deleted out what I think is to identifying but leave most of the document intact, so you have a good idea of what a report would look like for you. Mine is from 2010, so not sure what has changed?

GG

You might be more moderate and be able to push yourself, but lets says you are on the lower end of the spectrum, push yourself to hard and be long that bottom with likely no aide? I would Always say, listen to your body, mine has decent to me (considering the diagnosis) and just need lots of sleep, but with good segments of productivitiy.l

My question really is about the semantics of 'crash' and 'PEM'. I guess I used to use both these words somewhat interchangeably and wanted to ask PRers what they think.

In my experience with ME, PEM, or a worsening of symptoms, happens after mental or physical overexertion. When I have too many periods overexertion over a short enough length of time without sufficient rest (or a continually long overexertion) then the PEM continues to build until I have a crash. Rarely too I've had crashes that seem to have come out of nowhere and didn't appear to be preceded by PEM.

So these words are distinct but related phenomena to me. What do you think? :nerd:
 

RyeRyeBread

Senior Member
Messages
123
Location
New Jersey, US
I use them interchangeably, and refer to the instances of my PEM as "crashes"

I crash/have PEM a few hours [sometimes days] after exertional activity, and the main crash/PEM lasts a few hours, but full recovery back to baseline lasts days. So overall, hours-days and I consider the whole thing PEM or a crash.

I usually say "I'm in a crash", "I'm crashing", or "shit I'm gonna crash aren't I" and then experience PEM, rather than saying I'm "experiencing PEM" simply because crash can be used as a verb and a noun and is easier and simpler to say for me lol

Sometimes I do find myself speaking of the main, bedridden episode of my PEM as simply "PEM", and the aftermath/recovery period as the "crash" --- so, I suppose there is a bit of give there 🤷‍♂️