Post-exertional symptoms distinguish myalgic encephalomyelitis/chronic fatigue syndrome subjects from healthy controls, 2020, Mateo et al

Andy

Retired committee member
BACKGROUND: Post-exertional malaise (PEM) is an exacerbation of symptoms that leads to a reduction in functionality. Recognition of PEM is important for the diagnosis and treatment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

OBJECTIVE: Symptoms following cardiopulmonary exercise testing were compared between ME/CFS patients and healthy controls.

METHODS: Open-ended questionnaires were provided to subjects following two maximal exercise tests, 24 hours apart. Subjects evaluated how they felt at five time points. Responses were classified into 19 symptom categories.

RESULTS: ME/CFS subjects (n = 49) reported an average of 14±7 symptoms compared to 4±3 by controls (n = 10). During the seven days afterwards, ME/CFS subjects reported 4±3 symptoms. None were reported by controls. Fatigue, cognitive dysfunction, and sleep problems were reported with the greatest frequency. ME/CFS patients reported more symptom categories at higher frequencies than controls. The largest differences were observed in cognitive dysfunction, decrease in function, and positive feelings.

CONCLUSIONS: A standardized exertional stimulus produced prolonged, diverse symptoms in ME/CFS subjects. This provides clues to the underlying pathophysiology of ME/CFS, leading to improved diagnosis and treatment.
Paywall, https://content.iospress.com/articles/work/wor203168
Sci hub, https://sci-hub.tw/10.3233/WOR-203168
 
"This paper also sheds light on the possible risks of a 2-day CPET. It does not appear that patients or research subjects suffer permanent or protracted damage from CPET. Our data show that recovery is bimodal, with approximately half of subjects taking a week or less to recover."

...

I do not see anywhere any notes on data taken that would back 'do not suffer protracted damage (let alone permenant)' in this study.

Isn't the last datapoint taken only a week out?
 
"This paper also sheds light on the possible risks of a 2-day CPET. It does not appear that patients or research subjects suffer permanent or protracted damage from CPET. Our data show that recovery is bimodal, with approximately half of subjects taking a week or less to recover."
Despite being in the field for at leat a decade, CPET researchers are still failing to collect and publish harms data. That is as unacceptable for biomedical research as it is for psychosocial research.
 
Despite being in the field for at leat a decade, CPET researchers are still failing to collect and publish harms data. That is as unacceptable for biomedical research as it is for psychosocial research.

Indeed particularly given Workwell who are the leaders in this field time-wise noted the harms potential from just one, as well as the indicators definitely noting harm from continual overdoing it. Ergo no researcher can pretend they weren't aware it was likely and so no excuse for not building proper testing/checking for that into their design protocol. It should be as standard this needs to be collected at 1,3,6months or more (as you carry on and then hit the wall at 6mnths I'd say more).

I think this area would benefit from proper conferences - or whatever the correct get-together term is - where they all begin to agree on what protocols need to be present in any research involving CPET including this harms follow-up (which could be updated as they discover more on the effectiveness of these vs others, but at least mean the data across studies is comparable as they are not cheap studies vs the methodologically useless BPS research, but this sort of 'snowball' value would make for a selling point in countering that issue).
 
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Despite being in the field for at leat a decade, CPET researchers are still failing to collect and publish harms data. That is as unacceptable for biomedical research as it is for psychosocial research.
The large CPET study based at Cornell University that had several report sessions at the latest IACFSME conference did follow up all their patients for at least a year.
 
I find it bizarre that I am one of the only people reporting great harm from two day CPET. When I contacted Maureen Hanson about that study, she said they had tested over 80 patients and all recovered to baseline. I guess I was just unlucky to go from moderate to severe.
 
Workwell and others have a major conflict of interest as it is one of the few services they offer.

Patients in the US are in such a difficult position as it seems objective evidence of disability is required to get a lot of disability payments.

Maybe but as they operate in the USA - which I get the impression is more litigious, but is also a commercial market (whereas socialised medicine this might be harder because of all the ideology that gets in the way there) - then I think they will want to be up with the facts on this in order to develop what they offer and evolve it at the same time as covering themselves re: careful methods and 'did all they could to be safe'. They need to keep it 'moving on' to stop competition.

CPET is probably copyable if you run it in a not very technical way with an eye to safety, but their very business model will need to mark out that this isn't the same thing for all sorts of reasons some of which we are all too aware of. Otherwise you'll have discounted cut-down versions on a budget entering the market (from local gyms or HCP centres etc).

I also expect there is limited business opportunity in this vs being so knowledgeable you can contribute to the actual management of people's condition vs a one-off test (and so it's really not worth risking being sued on that/reputation issues when they go off to someone else after getting results for 'treatment/management'). I'd imagine they are as interested as us in looking into harms and safety not just for this but because of the reputational issues even if a copy-cat version caused harm etc. and the impact that would have on the longeivity of all their work (they don't just do ME/CFS and CPETs I believe).

I think their being able to properly map PEM over long periods of time and the possibilities this or other areas they look into can provide into research and developments in the future is probably more 'the business' but getting people in to do 2-day CPETs has to be funded/viable at the same time in order to get anywhere? They are still exercise physiologists aren't they rather than a company offering technical tests as the 'mission statement/reason for being'? I know as things expand these emphases can change which do lead to different models and changes in direction and staff work etc.

That is just my top of head thoughts so interested to hear other things I haven't thought of as I can see the pressure short-term certainly of bottom lines, particularly if there is a quarterly revenue type thing behind them or investors or whatever the funding base and make-up is?

EDIT: If they can measure PEM and how long it lasts in individuals (ie their own individualised testing) they can inform if not 'recovery' but adjustment plans from mapping how different types of people did (with different exertion loads and plans for xyrs after testing) - they stop ME/CFS disability from being a declarative yes/no with a black box for patient (and being believed) on how much they can do/rest they need to not hurt themselves more longer term.

They can map actual recovery-non-recovery stats how they should be ie improvement and decline as much as 'recovered and not recovered'. They can be the test of what treatments actually improve the disease long term if they are found (so we don't have 'felt better at 6mnths' then everyone drops off a cliff as it was just hiding the effects of exertion medium-term). They might get good enough at the data to pick up on pointers where to look research-wise or shorter-term indicators a treatment might seem good for one function but is likely to end in bounce-back etc.
 
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I find it bizarre that I am one of the only people reporting great harm from two day CPET. When I contacted Maureen Hanson about that study, she said they had tested over 80 patients and all recovered to baseline. I guess I was just unlucky to go from moderate to severe.
I'm really sorry to hear of your bad experience.

My notes on the talk about recovery times in that study are here:
https://www.s4me.info/threads/iacfs...9-july-9-am-to-4-40-pm-edt.28755/#post-430846
Of the 85 pwME who did the 2 day CPET in that study, the mean recovery to pre test severity was 12 days, and one of the 85 was not back to their pretest level after a year.

To be fair to Workwell, I think I remember them saying only do a 2 day CPET if you are in a study, or if you can't get recognition of illness for financial support any other way, because it does carry a risk of long term worsening.
 
> litigious

possibly an industry has to GET sued, and significantly lose, for some to take harm seriously? [eta in general, not this industry only.]

i'd like to see a focused legal charity. criminal too.
 
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My notes on the talk about recovery times in that study are here:
https://www.s4me.info/threads/iacfs...9-july-9-am-to-4-40-pm-edt.28755/#post-430846
Of the 85 pwME who did the 2 day CPET in that study, the mean recovery to pre test severity was 12 days, and one of the 85 was not back to their pretest level after a year.
Has this been published yet? It would be good to have more detail. E.g. anything over 3 months to recovery I woulc call a relapse. But I am pleased they are finally reporting data.

I'd also be interested to see the severity of people who volunteer for CPETs - how representative are they of PwME?
 
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