A Brief Questionnaire to Assess Post-Exertional Malaise 2018 Cotler, Jason et al

Abstract

Post-exertional malaise (PEM) is a key symptom of myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS). Currently, five PEM-items from the DePaul Symptom Questionnaire (DSQ) were recommended as a first step in measuring this symptom for patients with ME and CFS by the National Institutes of Health/Centers for Disease Control and Prevention (NIH/CDC) Common Data Elements’ (CDE) working group. The second step in this process, as recommended by the NIH/CDC CDE working group, involves assembling information from various sources to confirm the presence of PEM. There have not been any efforts, to date, to standardize this second-step process in the assessment of PEM. The current study examined whether five supplementary items on the DSQ could be used to operationalize the second step of the recommendations made by the NIH/CDC CDE working group. The five supplementary DSQ PEM duration items correctly categorized patients with ME or CFS 81.7% of the time, while incorrectly categorizing multiple sclerosis (MS) and post-polio syndrome (PPS) as ME or CFS only 16.6% of the time. The findings suggested that a PEM second-step process could be operationalized using supplementary DSQ items.

Open access, www.mdpi.com/2075-4418/8/3/66/htm

 

The questions and scoring.

Frequency

Throughout the past 6 months, how often have you had this symptom?
For each symptom listed below, circle a number from:
0 = none of the time
1 = a little of the time
2 = about half the time
3 = most of the time
4 = all of the time

Severity

Throughout the past 6 months, how much has this symptom bothered you?
For each symptom listed below, circle a number from:
0 = symptom not present
1 = mild
2 = moderate
3 = severe
4= very severe

These questions ask the patients for frequency and severity as above:

1. Dead, heavy feeling after starting to exercise
2. Next day soreness or fatigue after non-strenuous, everyday activities
3. Mentally tired after the slightest effort
4. Minimum exercise makes you physically tired
5. Physically drained or sick after mild activity

These questions are answered either Yes or No.

6. If you were to become exhausted after actively participating in extracurricular activities, sports, or outings with friends, would you recover within an hour or two after the activity ended?
7. Do you experience a worsening of your fatigue/energy related illness after engaging in minimal physical effort?
8. Do you experience a worsening of your fatigue/energy related illness after engaging in mental effort?

This question asks for length of time (<1 h, 2–3 h, 4–10 h, 11–13 h, 14–23 h or ≥ 24 h)

9. If you feel worse after activities, how long does this last?

This question is answered either Yes or No.

10. If you do not exercise, is it because exercise makes your symptoms worse?


DSQ-PEM Scoring

Scoring Step 1
Items 1–5: A frequency and severity score of 2, 2 on any items 1–5 is indicative of PEM.

Scoring Step 2
Items 7, 8: Either item 7 or 8 must have an answer of yes to indicate an ME and/or CFS dx.

Item 9: A response of >14 h is needed to indicate an ME and/or CFS dx.

Items 6, 10: Neither item indicates an ME and/or CFS diagnosis, but provides a description of patient PEM for clinical evaluations.

 

good grief... how long's a piece of string?!

It depends what the activity was & how much of it i did.

 

I'm not clear what is meant by 'soreness'. To me it is a superficial pain, e.g. from a graze.

 

ME's PESE is often delayed by 3 days. I was often bedridden 3 days after doing something I had thought was within my capabilities and feeling fine till then. Yet I would not be diagnosed as having ME by this questionnaire.

Why does Jason miss the mark about ME so often? Is he still caught up in the way they spoke about CFS?

 

Somehow, I missed this paper when it came out, but I think it's important as it deals with the shortcoming of the original DSQ-PEM questions, which also capture simple exertion intolerance. Exertion intolerance is common to many illnesses and those with deconditioning, and one Lenny Jason study found nearly 2/3 of people with MS met the DSQ criteria for PEM.

Commentary​

In a nutshell. Adding a single question about PEM duration to DSQ assessment of post – exertional malaise seems to dramatically increase its accuracy. The study also provides evidence that PEM is not unique to ME/CFS – a minority of people with MS and post polio syndrome also appear to experience it.

DSQ assessment of post-exertional malaise

The DSQ was considered by the NIH/CDC common data elements (CDE) working group to assess PEM. The DSQ asks about frequency and severity of these five “PEM” items:

1. Dead, heavy feeling after starting to exercise
2. Next day soreness or fatigue after non-strenuous, everyday activities
3. Mentally tired after the slightest effort
4. Minimum exercise makes you physically tired
5. Physically drained or sick after mild activity

People on this forum criticised the use of these questions because they equally describe simple exertion intolerance, and S4ME made this point in a formal submission.

Nonetheless, the NIH/CDC subcommittee recommended the DSQ as the first step, but also recommended getting further information to confirm the presence of PEM as a second step.

The study

The study tests the ability of five supplementary questions to provide further information for the second step above. I like the method of comparing the ability of DSQ items to differentiate between ME both MS and post polio syndrome, PPS.

Only one of 5 supplementary questions proved useful:

9. If you feel worse after activities, how long does this last?

The results for this question are given in table 3 and graphed below



Strikingly, there is a bimodal distribution for all three illnesses. This is usually a sign of two different things going on, probably exertion intolerance and post-exertional exertional malaise. The 4-10 hour category (seven hours) is unhelpful, as it masks the low point separating the two distributions.

Evidence of post-exertional malaise in other illnesses.

Notes that 22% of people with MS and 29% of those with post polio syndrome report PEM duration of at least 11 hours (mostly over 14 hours). This strongly suggest that some people with these illnesses do experience post-exertional malaise, though neither MS nor PPS shows the big increase in proportion experiencing PEM after 24 hours.

The statements that PEM is unique to ME has never been supported by hard evidence. This survey of 704 people provides the first evidence that it is not. The study used a convenience sample recruited from forums, social media et cetera, so probably includes more severe cases of all three illnesses. So it won't be fully representative. But it would be interesting to see studies looking at other illnesses with more representative samples and more finely grained time sampling.

Value of the PEM-duration questions shown by its high specificity and sensitivity.

Astonishingly, using the item about PEM duration gives an area under the curve of 0.88 (possible range 0.5-1.0), better than most putative biomarkers achieve. Put simply, using this question alone identifies most self-reported cases of ME and only a minority of cases of MS and PPS. It's interesting that while the DSQ using just the five core PEM questions found a PEM rate of over 60% for MS, but with the duration question it is down to 22%.

The 2018 paper concludes, "an important next step, recommended by the NIH/CDC CDE working group, is to create an instrument with the sole purpose of more comprehensively assessing PEM.”

I haven't seen a new instrument emerge. But it looks to me like all that’s needed is to add the question about PEM duration to the original five PEM items.

Thought?

 

Or they could have ME/CFS themselves as well?

 

That’s a very good point for post polio syndrome given that it’s a post-infectious illness. I Wonder if anyone has ever looked at this?

I think it’s less likely for MS. Although EBV appears to be an essential step for development MS, it’s not a direct trigger. As with ME/CFS, glandular fever can be a trigger, but the odd ratios are small so it’s a marginal effect. MS doesn’t generally appear to be a post infectious illness.

That’s good point about dela, And how long it extends for beyond 24 hours. Though I don’t think PEM needs to last days to be PEM.

It would be interesting to know if people with MS and PPS similarly have a delay period before onset of post exertional malaise, And the average total duration.

However, the clear bimodal pattern does indicate that whatever it is happening 12 hours plus on is not simple exertion intolerance (i.e. it’s not a simple decay curve). If it’s not post exertional malaise, I’d be interested to know what it is. But it will be very helpful to have data on any delay time.

 

I more meant that it could be that those people who report PEM might have both PPS or MS as well as ME/CFS, assuming that they are distinct conditions.

 

As I got older I started to have muscle soreness. I would tell friends I worked have to look back two days to see what I'd been doing.

PEM for me is much the same. For a long time I didn't associate PEM with a mental/physical activity from several days ago.

Now I moderate the effects. If I have an event where I'll be walking, I don't walk as much the day before. I lie down before leaving for the event. I schedule time immediately after arriving home to go lie down. I reduce my expectations for the next few days .

It can take a long time to recognize and understand the full effects of PEM. I like the first few questions, particularly about feeling unusually ill almost immediately after an activity.

 

I don't think this study assessed symptoms other than fatigue (physical and mental) and pain? I would expect these to be common in a number of other diseases, including for longer than 14 hours. In fact I'm surprised the number of pwMS reporting this is not higher (I used to know quite a few people with MS during my time misdiagnosed with this).

Like you I'm yet to be convinced PEM is unique to ME and some LC. However, I have also yet to see any study that convincingly showed

a) the delay pattern, and

b) the much broader range of symptoms

For me these are the hallmarks of PEM that distinguish PEM from other forms of exertion intolerance.

To date I've seen only one other condition where descriptions have come close to possibly maybe reporting something similar to PEM and that's overtraining syndrome

 

And PEM leading to potentially permanent reduction in baseline functioning, eg post GET?

 

MS has very distinct clinical signs, especially with MRI scans (I don't know about PPS). The prevalence of ME is about 0.5%, yet 29% of people with PPS and 22% with MS report potential PEM symptoms, so the I don't think that's a strong possiblity.

I see relapses as separate from PEM. In my experience, relapse come with lots of PEM, but you can certainly have PEM without relapses. We don't have data for ME or PPS. There is relapsing/remitting MS, but I hadn't heard the relapses were triggered by exercise.

I'm not so sure because of the pattern of the data.

For MS we see a classic peak followed by decay for the response to exercise, peaking at 2-3 hours with only 3% of people reporting symptoms from 11-13 hours. This is followed by a new peak at 14 hours (as opposed to continued decay). This is a bimodal response, making it likely the second group (19%) with symptoms lasting much longer are responding in a different way

Interesting. I joined a pain support groups due to the severe pain I had early in my illness, and ddiscoverd that quite a lot of people with chronic pain had what sounded a lot like PEM triggered by minimal exertion - and also had relapses very easily.

 

What can we conclude about possible PEM in other illnesses?

It looks to me that a significant proportion of people with MS and PPS have symptoms that could be PEM rather than exertion intolerance.
ADDED And I think this is very significance, because I don’t think we’ve had any quantitative evidence before that people with other illnesses might experience PEM.

The options seems to be that either that this is PEM like that in ME, or it is something else that also differs from exertion intolerance. What we need to know are:

1. Is it delayed? @Trish
2. What are the symptoms, if any, beyond fatigue? @rvallee

Fatigue and 'feeling sick':
"Physically drained or sick after mild activity"

I don't know if anyone has defined the number or type of symptoms. The term is post-exertional malaise and malaise if the feeling of being well (e.g. the flu-like feeling). I think the question about feeling sick would cover that, but it's an 'or' option so we don't know.

Without new data, which I think means a new study, we won't know if people with other illnesses including MS and PPS have what we would recognise as PEM.

 

Yes, the 'or' is the problem here. And this one's not the only paper I've seen this 'or' in. There should be two separate questions - one about fatigue and one about feeling ill. Until researchers start asking more precise questions their papers remain uninterpretable

Which is why I wrote I haven't seen convincing descriptions of PEM in other conditions yet (apart from just maybe in OTS). It doesn't mean it's not there, just that hardly anyone is asking the right questions to find out either way. I agree with your conclusion that

 

I don't like this use of 'feeling sick' in a questionnaire. Does it mean feeling ill or the specific symptom of being nauseous?

I know there's the two countries divided by a language thing, but I think feeling sick is used to mean nauseous in the USA.

 

In my variety of English 'feeling sick' is ambiguous, it can mean both. In real life and in context the meaning is usually clear. But context is typically lacking in questionnaires, so yes, plenty of opportunity for confusion.

Ditto for 'feeling ill'. I've come across pwME who seem to be describing that fluey malaise feeling but say they don't feel ill because for them 'feeling ill' is defined by fever, coughs and sneezes.

Just goes to show how careful one has to be in phrasing questions. And that thoroughly testing questions on a wide range of people is not optional