Pain in adolescent chronic fatigue following Epstein-Barr virus infection, 2020, Wyller et al

[Andy]

Objectives
Acute Epstein-Barr virus (EBV) infection is a trigger of Chronic Fatigue (CF) and Chronic Fatigue Syndrome (CFS). The aim of this cross-sectional study was to investigate pain symptoms and pressure pain thresholds in fatigued and non-fatigued adolescents six months after acute EBV-infection, and in healthy controls. This study is part of the CEBA-project (CF following acute EBV infection in adolescents).

Methods
A total of 195 adolescents (12–20 years old) that had undergone an acute EBV infection six months prior to assessment were divided into fatigued (EBV CF+) and non-fatigued (EBV CF−) cases based on questionnaire score. The EBV CF+ cases were further sub-divided according to case definitions of CFS. In addition, a group of seventy healthy controls was included. Symptoms were mapped with questionnaires. Pressure pain thresholds were measured through pressure algometry. One way ANOVA were used for between-group analyses. Linear regression analyses were used to explore associations between Pediatric Quality of Life (dependent variable), pain symptoms and other variables within the EBV (CF+) group.

Results
The EBV CF+ group had significantly higher scores for pain symptoms as compared with the EBV CF− group and healthy controls, but pressure pain threshold did not differ significantly. The number of pain symptoms as well as pain severity were strongly and independently associated with quality of life.

Conclusions
CF and CFS following acute EBV-infection in adolescents is characterized by high pain symptom burden, which in turn is associated with a decline in quality of life. Pain in CF and CFS is of considerable clinical importance, and should be a focal point for further investigation and intervention in these patient groups.

Paywall, http://dx.doi.org/10.1515/sjpain-2020-0031
Sci hub, unable to access paper at time of posting.

 

[Midnattsol]

As with the CBT study, participants wore acceleromaters for a week. The chronic fatigue positive group had a daily mean of 8710 with an SD of 3872, while the chronic fatigue negative group had a daily average of 9329 with an SD of 3019. They don't write how PEM is measured (I guess the same way as in the CBT study, but who knows), but they did find that PEM was more related to quality of life than CFQ and HADS scores, that sounds like a finding that could have been explored more. Instead they write this in the discussion:

Other factors associated with poor quality of life include psychological symptoms such as anxiety and depression. Such symptoms may contribute to a spiral of negative thinking, worsening pain symptoms.

I'm not up for reading through the whole thing today. There is also an annoying amount of spelling errors, with sentences lacking punctuation and some sentences seem to not have been written in full (or more likely they have been rearranged). This really should have been cleared up before publication.

@Michiel Tack You will be happy to know that this time they at least include the sentence "We did not adjust p-values for test multiplicity".

 

[rvallee]

What's the point of asking about one single symptom rather than broadening to the whole range of symptoms? What does it tell us to obsessively focus on a single symptom like that? Seems like a very wasteful process in a disease characterized by a long list of symptoms, most of which are ignored. Especially as a full examination of symptoms is something that's badly missing, precisely why the May report by Body Politic remains the single most useful piece of research on long COVID published so far, because it did not start with assumptions and allowed for free answers that were actually analyzed and published.

For years medicine has ignored pain by focusing strictly and obsessively over fatigue and now this jerk is, what, trying to pass this as a discovery? What is this nonsense? This guy is a total amateur and a waste of academic resources.

 

[alktipping]

i think they were looking for evidence to prop up the sensitization theory which has no evidence but seems to be thrown about a lot in pain clinics .

 

[Hutan]

I haven't read the paper.

The abstract has some good points.

CF and CFS following acute EBV-infection in adolescents is characterized by high pain symptom burden, which in turn is associated with a decline in quality of life.

It gets the causal inference of 'pain>> reduced quality of life' right (even if, as Midnattsol has noted, the actual article is not so good about this).

I also like that it has separated out the pressure pain thresholds from other sorts of pain. There has been quite a lot of statements thrown around in the past that people with ME/CFS have low pain thresholds - that we are just somehow sensitive creatures, over-reacting to pain. Studies don't support that idea, and this one, with its finding of no difference in pressure pain threshold doesn't either.

(Edit - cross-posted with alktipping - yes, the central sensitisation theory is not supported by the finding.)

I like that it mentions that there is a high pain burden though and that it should be a focal point for investigation and treatment. For example, I get a sore throat when in bad PEM, as do many others. There must surely be something that can account for the pain. And yet I don't think I've ever seen an investigation into what might be the cause. (Of course, when treatment is mentioned, Wyller is no doubt including CBT in that. But still - the abstract is good.)

 

[Peter T]

I also like that it has separated out the pressure pain thresholds from other sorts of pain. There has been quite a lot of statements thrown around in the past that people with ME/CFS have low pain thresholds - that we are just somehow sensitive creatures, over-reacting to pain. Studies don't support that idea, and this one, with its finding of no difference in pressure pain threshold doesn't either.

In relation to myself, when I have pain that has no obvious external stimuli I have often wondered what my pain threshold is. Am I more sensitive to pain than pre onset or am I more habituated to pain? Subjectively with idiopathic pain it is impossible to know as there is no objective yard stick.

However one type of pain I experience regularly is in the jaw and the face, which does not feel severe enough to require a visit to the dentist with, but then on several occasions I subsequently discovered I have had an abscess or a dying nerve. So in this situation where I am unable to distinguish apparent idiopathic pain from pain attributable to concrete dental issues I seem to have easily tolerated levels of pain that normally would have seen people camping out at their dentist. If anything my problem is ignoring pain that is indicative of a need for medical intervention.

So where I am able to compare directly I suspect that I, if any thing, have a lower pain threshold than premorbidly.

Obviously this patient group in the study were subject to relatively novel stimuli and will have had a relatively recent onset, not having had twenty or thirty years of learning to ignore pain. So perhaps it is not surprising that they do not seem to have different pain thresholds than the normal controls.

[added - My suspicion is that more studies trying to examine more of our symptoms will produce patterns that surprise researchers, particularly those focused solely on fatigue, though not necessarily the patients.]

 

[Mithriel]

In relation to myself, when I have pain that has no obvious external stimuli I have often wondered what my pain threshold is. Am I more sensitive to pain than pre onset or am I more habituated to pain? Subjectively with idiopathic pain it is impossible to know as there is no objective yard stick.

However one type of pain I experience regularly is in the jaw and the face, which does not feel severe enough to require a visit to the dentist with, but then on several occasions I subsequently discovered I have had an abscess or a dying nerve. So in this situation where I am unable to distinguish apparent idiopathic pain from pain attributable to concrete dental issues I seem to have easily tolerated levels of pain that normally would have seen people camping out at their dentist. If anything my problem is ignoring pain that is indicative of a need for medical intervention.

So where I am able to compare directly I suspect that I, if any thing, have a lower pain threshold than premorbidly.

[added - My suspicion is that more studies trying to examine more of our symptoms will produce patterns that surprise researchers, particularly those focused solely on fatigue, though not necessarily the patients.]

It is very hard to compare pain thresholds. Getting students to hold a hand in ice water doesn't seem a good model for living with pain day in, day out.

I wonder if I am just being a bit of a wimp with all my symptoms but with the things it is possible to compare I am much more likely to put up with it. Dental pain is one that can be compared and sprains.

Then I read about treatments for medical problems and I find myself thinking that it never occurred to me that it was something you did not just put up with.

It works against us too. When I was in hospital and told the nurses I was blind, no one was very concerned. (They had switched on the lights when I was looking straight at them). I don't think they believed me as I was not making a big fuss and I was so used to it happening I used my everyday coping skills to work out where things were from touch and sound and slight variations in the darkness - I could tell where a nurse was because they had white uniforms.

 

[Snow Leopard]

A lack of difference in pressure-pain thresholds suggests the pain is not due to any sort of generalised central pain sensitisation.

 

[Marky]

As with the CBT study, participants wore acceleromaters for a week. The chronic fatigue positive group had a daily mean of 8710 with an SD of 3872, while the chronic fatigue negative group had a daily average of 9329 with an SD of 3019. They don't write how PEM is measured (I guess the same way as in the CBT study, but who knows), but they did find that PEM was more related to quality of life than CFQ and HADS scores, that sounds like a finding that could have been explored more. Instead they write this in the discussion:



I'm not up for reading through the whole thing today. There is also an annoying amount of spelling errors, with sentences lacking punctuation and some sentences seem to not have been written in full (or more likely they have been rearranged). This really should have been cleared up before publication.

@Michiel Tack You will be happy to know that this time they at least include the sentence "We did not adjust p-values for test multiplicity".

In the musical therapy for ME-study (lmfao), the participants also had similar high daily averages. He is not researching us who has problems getting out of the house in a consistent fashion, that is for sure

 

[Marky]

Im gonna be totally honest here

We dont need this type of research

Yes pain hurts

But give funding to someone who is actually capable of researching something worthwile, not the funding leeches

 

[Ravn]

A lack of difference in pressure-pain thresholds suggests the pain is not due to any sort of generalised central pain sensitisation.

That was my first thought, too. But I expect that somehow they'll manage to twist their findings into a version of there's nothing wrong with the peripheral nerves (normal pressure pain thresholds) therefore the high pain symptom load must be due to central sensitisation (amplification of normal bodily signals), which - of course - must be treated by CBT. With or without added music

A more general question. There are any number of studies looking at pain thresholds in various ways, plunging people's hands into cold water, applying pressure or capsaicin cream. But what practical relevance do such pain thresholds have?

In real life, including for the participants in the present study, most chronic pain is not the result of some external factor triggering temperature or pressure sensitive nerves.

Many types of pain like headaches, muscle or joint pain, pelvic pain, etc. are generated internally. Assuming there is an "internal pain threshold" for those types of pain, how is anyone to know how high it is, let alone how it relates to the externally triggered one?

And how do "external pain thresholds" relate to the number and severity of internally generated pain symptoms?

 

[Milo]

Without reading the paper, here is my comment:

CF and CFS following acute EBV-infection in adolescents is characterized by high pain symptom burden, which in turn is associated with a decline in quality of life. Pain in CF and CFS is of considerable clinical importance, and should be a focal point for further investigation and intervention in these patient groups.

Take home lessons: pain very bad, very bad pain, we must do something about that. Seemingly EBV infections means pain??? Should they investigate other onsets too?
Pain investigation means psych consult.
Pain intervention means rehab and CBT

 

[rvallee]

Without reading the paper, here is my comment:



Take home lessons: pain very bad, very bad pain, we must do something about that. Seemingly EBV infections means pain??? Should they investigate other onsets too?
Pain investigation means psych consult.
Pain intervention means rehab and CBT

Somehow, somewhere, a person who spent 10 years on an MD: "wait, myalgic means painful?!"

These people are so freaking weird. They should form a support group with HIV deniers who somehow accidentally stumble on the fact that AIDS is caused by a virus and somehow have to tell someone, anyone.