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Is NIH/CDC going to use the right PEM definition for all future research? Action needed?

Simon

Senior Member
Messages
3,789
Location
Monmouth, UK
The NIH/CDC are deciding on the “common data elements“, CDEs, that must be collected in all future studies they fund. And they’ve asked for patient comments on the draft proposals by 31 January.

Perhaps the most important of the CDEs covers post-exertional malaise (PEM), the cardinal symptom of the illness. The PEM working group has proposed using the PEM subscale from Lenny Jason’s DePaul Symptom Questionnaire (DSQ). However, I have concerns about its suitability and I’d like to hear what other patients think.

The DSQ will help define who has PEM and who does not (in some studies it will be the only measure used). If it’s inaccurate, it risks including patients who don’t have the illness and excluding those who do, weakening research.

The DSQ assesses PEM by asking patients to rate the severity and frequency of five symptoms over the last six months:
  • Dead, heavy feeling after starting to exercise.
  • Next day soreness or fatigue after non-strenuous, everyday activities.
  • Mentally tired after the slightest effort.
  • Minimum exercise makes you physically tired.
  • Physically drained or sick after mild activity.

However, I don’t feel that these questions capture the essence of PEM.
In fact, the working group itself has adopted the Institute of Medicine report’s definition of PEM:

Post-exertional malaise is defined as an abnormal response to minimal amounts of physical or cognitive exertion that is characterised by [my summary]:

  • A flare of some or all of an individual’s symptoms,
  • with an immediate or delayed onset and
  • with prolonged recovery.
  • Severity and duration of symptoms are out of proportion to the initial trigger.
  • There is a loss of functional capacity and/or stamina.

This looks to me like a good description of PEM but it’s substantially different from the DSQ.

Also, the DSQ asks patients to rate each item in terms of frequency and severity, and only those who get above a relatively high score will be classed as experiencing PEM (e.g. having the problem at least half the time). However, the frequency and severity of PEM depend not only on severity of illness but also on a patient’s level of exertion. Most patients pace themselves very carefully to try to avoid PEM, and those who do would be appear not to have PEM and would be excluded from every NIH and CDC study.

The working group are aware of this problem and talk about having researchers ask supplemental questions (e.g. the effect if/when they engage in physical or mental activity and whether there are activities they avoid because it exacerbates symptoms). But surely the better approach would be to use a questionnaire that asks patients directly what happens if they exert themselves, in order to reveal whether they have PEM?

If other patients share my concerns, then we need a clear plan from the NIH/CDC to urgently develop a replacement questionnaire, based on input from patients.

So I’d appreciate any answers to these questions:
  1. Does the DSQ fall short of properly capturing post-exertional malaise?
  2. If so, should we be asking for a timetabled plan to urgently develop a better alternative?

IMPORTANT. This is not intended as a criticism of Professor Leonard Jason, who has been a lonely pioneer of case definitions and PEM in particular. Without his and his team’s research there would be nothing to use now, and we do need something in the interim. Nor is this a criticism of the working group (co-chaired by Lily Chu and patient-advocate Mary Dimmock). This group has produced many good recommendations and has highlighted many of the weaknesses of the DSQ.

This, though, is about how PEM will be defined in every NIH and CDC study, including every biomedical study, so it needs to be as good as it can be, as soon as possible, to produce the best possible research.
 

Simon

Senior Member
Messages
3,789
Location
Monmouth, UK
Why the PEM subgroup chose the DSQ

The subgroup chose the DSQ PEM subscale as the only option that’s currently “ready-to-go” (or close to it), given a total lack of alternatives.

While not perfect, the PEM subscale of DSQ is the best choice at this time for a standard method of identifying the existence of PEM in a research study participant... has been tested and used in several ME/CFS studies, has been evaluated in multiple diseases, includes a PEM subscale, and has been used by different researchers.

The subscale also recognise limitations, not least that it’s never been validated to show that it really does identify PEM (only that it’s part of the whole DSQ that can identify patients from healthy controls). The DSQ has only been shown to discriminate one illness from patients, in one study.

The subgroup also calls for more research on their chosen scale.

However, if it’s not the right tool to properly identify PEM, the key symptom of this illness, then I believe we need a more radical approach to urgently develop an alternative. Note that this would need to be validated and tested against the DSQ.

Read the full 28-page document here.

Here's the full version of the Institue of Medicine (now National Academy of Medicine) PEM definition that the subgroup has adopted:

PEM is defined as an abnormal response to minimal amounts of physical or cognitive exertion that is characterized by:

1. Exacerbation of some or all of an individual study participant's ME/CFS symptoms. Symptoms exacerbated can include physical fatigue, cognitive fatigue, problems thinking (e.g. slowed information processing speed, memory, concentration), unrefreshing sleep, muscle pain, joint pain, headaches, weakness/instability, light-headedness, flu-like symptoms, sore throat, nausea, and other symptoms. Study participants can experience new or non-typical symptoms as well as exacerbation of their more typical symptoms.

2. Loss of stamina and/or functional capacity

3. An onset that can be immediate or delayed after the exertional stimulus by hours or days but the exact timing is not well understood.

4. A prolonged, unpredictable recovery period that may last days, weeks, or even months.

5. Severity and duration of symptoms that is often out-of-proportion to the type, intensity, frequency, and/or duration of the exertion. For some study participants, even basic activities of daily living like toileting, bathing, dressing, communicating, and reading can trigger PEM.

I’ve already posted also this on S4ME as I want to reach as many patients as possible
 

Sasha

Fine, thank you
Messages
17,863
Location
UK
Thanks for posting this, @Simon. I think this issue of common data elements is hugely important - one of the most important things of 2018, actually.

These data elements are going to be the things that select which patients go into all future NIH and CDC studies and how they're measured. If they're wrong, we'll have the wrong patients in the studies; the wrong way of measuring whether treatments work or not; and measures that don't reflect our health and so can't correlate with biomarkers.

Research will be wrecked in all sorts of ways if we don't get this right, and not just in the US. The NIH/CDC's choice of measures is likely to be copied by other researchers worldwide.

I'm very pleased that the NIH/CDC are consulting with patients over their choices. Let's take this opportunity to help them to help us, especially for this crucial PEM measure.

I share all of your concerns about this PEM measure, @Simon. I have great respect for Lenny Jason but I don't recognise my own PEM from his descriptors. I took part in the research that led to them and felt that the questionnaire used in the study forced me to answer in ways that didn't reflect my experience.
 

Ravn

Senior Member
Messages
147
@Simon, in answer to your questions: yes and yes.
I'm not up to reading the full documents or giving detailed comment but for what it's worth:
Your definition of PEM is by far the better. It certainly captures my PEM very well whereas the other definition does so poorly.
I share your concern about patients who pace well - and therefore do not experience PEM, or only mild PEM - being excluded from consideration.
And I agree with you and @Sasha that getting this right is crucial for getting quality research results in the future by selecting only participants who actually have well-defined ME.
 

Simon

Senior Member
Messages
3,789
Location
Monmouth, UK
@Simon, in answer to your questions: yes and yes.
I'm not up to reading the full documents or giving detailed comment but for what it's worth:
Your definition of PEM is by far the better. It certainly captures my PEM very well whereas the other definition does so poorly.
I share your concern about patients who pace well - and therefore do not experience PEM, or only mild PEM - being excluded from consideration
thanks, Ravn. Just to clarify the definition you like comes from the Institute of Medicine and was the one adopted by the subgroup itself.
 

Wally

Senior Member
Messages
1,167
Yes, @Simon - I have some similar concerns about this subject matter. Unfortunately, I lost December and now the first part of January due to illness. (I always feel like this illness is throwing obstacles in my path leaving me ten (10) steps behind where I would like to be in advocating for patients with this illness.)

If you can give some additional time and bumps to this thread in receiving input on your questions, I think this might be a good advocacy project for PR members. If you would like to open this topic as more of a project to be tackled by a group of individuals thru the tools offered by PR, then I would be glad to help put something in the Advocacy Project Subforum. If you would rather do something more informally that could work too. Either way, if you are interested I would try to have my comments to you by next Wed.

If location of this discussion should change it will be really helpful if the individual threads can be grouped together or at least contain a reference where these other threads can be found.

Wally
 

medfeb

Senior Member
Messages
491
Hi

Great to see those here reviewing these CDEs. I was one of the participants of the PEM CDE group and am looking forward to seeing your review.

If you don't mind, I'd like to clarify one thing...
The PEM recommendations include the definition of PEM but separately we also needed a tool that a trial participant could respond to regarding their experience of PEM. The definition itself doesn't do that. Also, this instrument needed to be an existing tool with some studies/evidence behind it - if we were to try to develop something new, we would have no way of knowing it would work.

We recommended DSQ for use as a starting point because it reflects PEM better than any alternative patient reported instruments for PEM and because it has the most research and evidence behind it. We also included a recommendation for further research to evolve how PEM is assessed to ensure it reflects the full patient experience. The 28 page PEM CDE document with the full list of recommendations for future research and also guidance for the conduct of PEM focused studies is here.

I really appreciate your looking at this and letting us know what gaps and issues you see.
Mary
 

andyguitar

Moderator
Messages
6,595
Location
South east England
Hats off to NIH/CDC for including patients in all this. This is a very positive sign that ME/CFS is now going to be delt with in a much more scientific way than it has been for decades. I am hopeful that in the UK N.I.C.E will also take note of what sufferers think when they rewrite the guidelines for Docs ect. The tide is turning now and there is much to look forward to.
 

Learner1

Senior Member
Messages
6,305
Location
Pacific Northwest
Hi

Great to see those here reviewing these CDEs. I was one of the participants of the PEM CDE group and am looking forward to seeing your review.

If you don't mind, I'd like to clarify one thing...
The PEM recommendations include the definition of PEM but separately we also needed a tool that a trial participant could respond to regarding their experience of PEM. The definition itself doesn't do that. Also, this instrument needed to be an existing tool with some studies/evidence behind it - if we were to try to develop something new, we would have no way of knowing it would work.

We recommended DSQ for use as a starting point because it reflects PEM better than any alternative patient reported instruments for PEM and because it has the most research and evidence behind it. We also included a recommendation for further research to evolve how PEM is assessed to ensure it reflects the full patient experience. The 28 page PEM CDE document with the full list of recommendations for future research and also guidance for the conduct of PEM focused studies is here.

I really appreciate your looking at this and letting us know what gaps and issues you see.
Mary
I just read the 28 page document. Most of it looks very good.

However, the DSQ symptom questionnaire looks problematic to me.

It asks for frequency and severity in the past 6 months, which previous posters have pointed out may be a problem if one has been trying NOT to provoke PEM.

Then. It assumes we can't exercise at all, and that PEM will be provoked after starting exercise or a minimal quantity of exercise. This is not necessarily the case. Many of us can do a careful amount of exercise without triggering PEM - it is only after going over some arbitrary threshold that PEM is triggered, and that PEM can be substantial.

Similarly, many of us can make a minimal mental effort just fine. It is only after reaching some threshold of cognitive effort (or emotional stress which is not mentioned anywhere) that PEM van be triggered.

In summary, if you're going to use that questionnaire, you'll be limited to a specific subgroup of patients that wilts at the most minimal effort and is ineffective at avoiding PEM.

This could miss a great many patients, which could skew the results.
 

andyguitar

Moderator
Messages
6,595
Location
South east England
Yes @Learner1 you are probably right that the results will be a bit skewed and many will be missed. I dont know how things work in the USA when it comes to an ordinary citizen such as yourself making representations to NIH/CDC, but why not share your concerns with them? They may just have overlooked what is obvious here.
 

Ravn

Senior Member
Messages
147

Nielk

Senior Member
Messages
6,970
It Looks like the usual HHS "patient engagement" myth going on here. HHS with their several subgroups have worked on this for months and have posted their results. We are asked to comment now on their results. They will not change anything based on some patient/advocate comments. As @medfeb who was part of the PEM workshop posted above, the workshop decided that there are no other tested questionnaires for PEM and they do not shoe any desire to improve on it. They will file all our comments with the previous comments of the past 30 years and claim that they sought and received patient comments.

Although there has been no testing of the IOM criteria, not official announcement of adaptation - it seems like CDC and now NIH are committed in using the (in my opinion flawed) IOM criteria. The only symptom which differentiates ME from many other conditions under the IOM criteria is PEM. Without PEM, it is just common place fatigue suffered by millions who suffer from some form of insomnia.

If PEM is not well defined and people who just tire more easily because they are already weak from insomnia or from some other common condition get selected for studies in ME, it will skew the results.
 

medfeb

Senior Member
Messages
491
the workshop decided that there are no other tested questionnaires for PEM and they do not shoe any desire to improve on it.

Hi @Nielk - I am not aware of any other tested questionairres for PEM. If you do know of any, I encourage you to provide that feedback during the public review. I am honestly looking forward to seeing all the feedback that comes in so we can get this right.
 

medfeb

Senior Member
Messages
491
I just read the 28 page document. Most of it looks very good.

However, the DSQ symptom questionnaire looks problematic to me.

It asks for frequency and severity in the past 6 months, which previous posters have pointed out may be a problem if one has been trying NOT to provoke PEM.

Then. It assumes we can't exercise at all, and that PEM will be provoked after starting exercise or a minimal quantity of exercise. This is not necessarily the case. Many of us can do a careful amount of exercise without triggering PEM - it is only after going over some arbitrary threshold that PEM is triggered, and that PEM can be substantial.

Similarly, many of us can make a minimal mental effort just fine. It is only after reaching some threshold of cognitive effort (or emotional stress which is not mentioned anywhere) that PEM van be triggered.

In summary, if you're going to use that questionnaire, you'll be limited to a specific subgroup of patients that wilts at the most minimal effort and is ineffective at avoiding PEM.

This could miss a great many patients, which could skew the results.

@Learner1 - If you could submit your comments, that would be really helpful.
 

Simon

Senior Member
Messages
3,789
Location
Monmouth, UK
I'd be happy to. Can you either post or PM me where/how to send it and I'll do so?
Consultation:

Anyone can write in, anytime – up til Jan 31st deadline. Should we combine to offer comments on PEM? Anyone at S4ME have an opinion on this? @@Andy @@Valentijn. I guess it depends on how the discussion goes.

“We are in the process of finalizing these documents and would like to urge you to help by contributing your expertise during this public review period.

Please send all comments to NINDSCDE@emmes.com by January 31, 2018.

After this open comment period, the ME/CFS Working Group will review and revise the recommendations. Version 1.0 of the ME/CFS CDE recommendations will be posted at the end of February 2018.”

There may be an opportunity to do something collectively too.