Adverse outcomes in trials of graded exercise therapy for adult patients with chronic fatigue syndrome, 2021, White & Etherington

so no delay?

in 2007 guidelines:
"characterised by post-exertional malaise and/or fatigue (typically delayed, for example by at least 24 hours, with slow recovery over several days)"

https://www.nice.org.uk/guidance/cg53/chapter/1-Guidance
Interesting that PACE (unless I've missed something, which is possible) only used a 1994 suggestion (cannot call it a definition) of what characterises PEM, rather than the 2007 NICE guideline. I know PACE might have just missed that boat, but weren't some PACE authors involved in that guideline anyway, so must have had good awareness.
 
Eurgh!!! How patronising! "Exercise can feel unpleasant!"

Not to mention that many of us played sports at some time in our lives. Many of those sports are seasonal so there is a period of retraining at the start of the season.

Even those who didn't play seasonal sports would have had to take time out occasionally because of exams, holidays, other illnesses etc and then gone back to their physical exercise or sport of choice.

We know what physical exercise when you haven't done any for quite some time and retraining for seasonal sports feels like.

Having experienced both return to exercise and retraining and how exercise now causes us to feel I think we are better placed to tell them what the differences are rather then the cart before the horse of them telling us.

More than anything else this demonstrates the sheer hubris of them thinking they know best.
 
Thank you. I somehow missed that post.

Some comments on the CGI scores

The authors say they chose CGI because "Some trials also reported clinical global impression (CGI) change scores of overall health, but rarely interpreted the data regarding deterioration on this measure" which seems arbitrary to me rather than a good reason. They were also given unpublished CGI scores from a trial by Moss Morris et al. CGI scores were not available for all trials. All this seems a little suspicious to me (why not use the studies own data on harms?). The real reason for choosing CGI could be that that this happened to be the outcome that gave the most favorable safety profile across all choices.

Risk of bias
The risk of bias was previously assessed for eight of the trials by the Cochrane review [5], which found a high risk of bias in all eight trials for the lack of blinding of participants and outcome assessors, a high risk of other biases for two other trials [13, 14], and an unclear risk of a selective reporting bias in five trials [5]. Our risk of bias assessment for the more recent two trials [6, 7] showed the same high risk of bias for blinding of participants and outcome assessors in both trials, no other high or uncertain risks in one trial [6], but high or uncertain risks of other biases in the other (pilot) trial [7]. The GRADE ratings of the certainty of the evidence regarding all three outcomes are given in table 2, and was low for all three comparisons, downgraded by two levels on the grounds of imprecision.

Have they ever admitted before that these studies have such big problems with bias?

The evidence that GET is unsafe
Geraghty and colleagues reviewed results from surveys of over 18,000 patients and concluded that; “graded exercise therapy brings about large negative responses in patients (54%–74%)” [30].

There are two main problems in interpreting the evidence from patient group surveys and qualitative studies. Firstly, we cannot be sure that patients in most of these studies actually had CFS. One study of patient group members showed that only a third had confirmed CFS after a standardised clinical assessment [31]

Here the vague possibility that maybe these numerous reports of harm are all due to widespread misdiagnosis is introduced, in the hopes of persuading the reader to believe that maybe if everything was done properly there would be no harm. But to make this explanation work would require believing in too many unlikely things: that somehow, multiple surveys happen to have receive responses in high proportion from patients with illnesses that are misdiagnosed with CFS and despite looking similar to CFS actually have a totally different response to GET. The authors are proposing an absurd scenario here.

"only a third had confirmed CFS" also doesn't mean that only a third had CFS. What is meant is that only a third did not have any exclusionary conditions that would disqualify a patient from a CFS diagnosis with Fukuda criteria. A patient with true CFS and type 2 diabetes would not be counted as confirmed CFS case.

Secondly, we cannot be certain that all those who reported that they had received GET had indeed received it, provided by a specialist therapist, trained in CFS/ME, and in a manner consistent with the 2007 NICE guidelines

As I recall there is some survey evidence that suggests GET by a trained specialists has the same rate of harm as patients undertaking GET on their own.

Does having post-exertional malaise mean that GET should not be provided?
At a logical level, it makes sense that one should not ask patients with PEM to increase their activity. But is there evidence that this is the case? One trial used CFS criteria, which required all participants to report PEM, and found no evidence of harm after guided self-helped based on GET, in any of six measures of safety [6].

This is incorrect. The GETSET trial says

In this trial, we recruited participants who met the NICE criteria,3 which are used by NHS clinicians. The NICE criteria require at least 4 months of clinically evaluated, unexplained, persistent, or relapsing fatigue with a definite onset that has resulted in a substantial reduction in activity and that is characterised by postexertional malaise or fatigue, or both.

Furthermore, the PACE trial showed that PEM was most likely to improve after GET, compared to comparison treatments of adaptive pacing therapy and specialist medical care [4]. We need more trials to be sure, but currently there is no trial evidence to support this concern

But we don't know if the improvement was real or just an artifact of poor controls. It's also not clear whether there was an adequate distinction between postexertional fatigue and postexertional malaise because they seem to be used interchangably while many now view them as two different things.

There is also the usual issue of participant activity levels not being objectively recorded so it's unclear whether they actually increased their activity levels and what effects this had on their symptoms.

I also note the choice of words "no trial evidence" and think of the objective evidence of deterioration in the 2-day CPET literature. Not mentioning this literature is a serious omission in a paper about potential harms of exercise.

What if GET was banned?
We suggest that the alternative of encouraging rest and inactivity risks the well-known health consequences of such an approach

They present a false dichotomy of GET equals activity, no GET equals inactivity. Patients are capable of self-managing their own activity levels and GET is not the only possible way to engage with exercise. As far as I know according to the published studies GET doesn't lead to an improvement in activity levels or fitness so one cannot attribute the positive health effects that come with increasing activity levels and fitness to GET.
 
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What if GET was banned?


They present a false dichotomy of GET equals activity, no GET equals inactivity. Patients are capable of self-managing their own activity levels and GET is not the only possible way to engage with exercise. As far as I know according to the published studies GET doesn't lead to an improvement in activity levels or fitness so one cannot attribute the positive health effects that come with increasing activity levels and fitness to GET.

This is a very important point. I see so many CBT/GET proponents who present it as: "you either start GET and CBT, gradually raise your activity level and recover, or you lay in the darkness 24 hours a day for the rest of your life - the choice is yours!". And most of the time they aren't even challenged on the ridiculousness of this assumption! As if these two extremes are the only possible alternatives.

There's also the alternative of keeping your activity levels moderate and stable over time, without forcing an increase in activity. This would avoid both the detrimental effects of total bedrest and of the possible damage incurred by regularly triggering PEM. The assumption that the alternative to GET is total bedrest 24 hours a day is a strawman argument, but it's one that they get away with suprisingly often.
 
The first thing I thought when I saw the abstract of this paper was this:



Having now seen the paper, I don't think they provide an adequate explanation.
The measures of safety we report were: the number of participants withdrawing from treatment and the numbers dropping out of trial followup.

although they do acknowledge it:
We cannot know whether trial follow up drop-outs occurred due to the nature of GET, or for some other reason, but this increased risk needs further exploration.

but is that just for convenience?
However, 4% more GET participants dropped out of follow-up by the end of the trials, compared to those receiving the control interventions, a significant difference.

There were more drop-outs in the GET group in PACE, but also more pts who failed to complete the 6mWT at 52 weeks (who didn't drop out). I think I've shown elsewhere (yep, it's here) that it is likely that this was at least partly correlated with lower physical function at 52 weeks.

But the main thing is that White was PI (or at least involved) in these trials. He could have directly asked pts *why* they dropped out, had he wanted to. And he could have directly asked about harms in a follow-up questionnaire. But he hasn't. This is an entirely vague and hand-wavey way of not answering that question.

eta: There's no real substitute for asking pts what they think: https://bmjopen.bmj.com/content/9/6/e021959 and https://www.patientcentra.com/patient-recruitment-insights/why-patients-drop-out-of-clinical-trials
 
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While the GET group did post a statistically significant improvement in one of the measures—the six-minute walking test—the marginal reported benefits were clinically insignificant.

Not a stats guy, so could be talking complete shite, but...

PACE used four objective outcome measures, for four different arms, which gives 16 separate results, only one of which reached statistical significance.

Using p = 0.05, we would expect 1 in 20 measures to reach significance purely by chance.

1 in 16 is not far from that.
 
While the GET group did post a statistically significant improvement in one of the measures—the six-minute walking test—the marginal reported benefits were clinically insignificant.

Not a stats guy, so could be talking complete shite, but...

PACE used four objective outcome measures, for four different arms, which gives 16 separate results, only one of which reached statistical significance.

Using p = 0.05, we would expect 1 in 20 measures to reach significance purely by chance.

1 in 16 is not far from that.


Yes they should have done a correction for the number of primary outcomes.

There is also the issue of dropouts.
 
"In fact, the PACE trial—..—included four objective outcomes.

None of them matched the subjective claims of improvement.

While the GET group did post a statistically significant improvement in one of the measures—the six-minute walking test—the marginal reported benefits were clinically insignificant.

At the end of PACE, GET participants still performed much more poorly on this measure than healthy women from 70 to 79 years old as well as patients with pacemakers, Class II heart failure, cystic fibrosis and other major health conditions.

They were also no more likely to be working, no more likely to be off social benefits, and no more physically fit than before, as measured by a step-test.

These poor objective results are unmentioned by Professor White in the new paper—a telling omission."

worth repeating.
 
Yes they should have done a correction for the number of primary outcomes.

There is also the issue of dropouts.

Right, only 3/4 did the six-minute walking test by the end. There is so much to criticize. Hard to include everything in a letter. I decided to focus on factors that would undermine White's claim of "effectiveness" sufficiently to require a correction.
 
Self-ratings of Clinical Global Impression (CGI) change scores of 6 or 7 (“much worse” or “very much worse”),​

So, getting worse does not count as worse in fact? This sounds like bimodal scoring a la PACE trial again.

Null results - are they really what is worth funding? What would be the results for:
No change +
Worse +
Much Worse +
Very Much Worse?


Control intervention

What?? If it's a control then what exactly is the intervention and how do we know it is actually safe?

Remember that Specialist Medical Care (SSMC) in the PACE trial was mostly provided by Simon Wessely, and used as a false comparison?

Probably safe

Authors shoot themselves in the foot here, accepting that GET may not be safe after all. After 14 years of GET "probably safe" is not good enough.

When CFS definitions including more non-ME patients than ME patients...

Low on GRADE

NICE won't be impressed, and we can be pretty sure it's more likely to be very low evidence.

Full FOIA needed for data please

Included studies will not doubt include this gem from the FINE trial:

"The bastards just don't want to get better"
Not exactly something that sounds like a situation involving safe treatment.

List of excluded studies, anyone?
 
Didn't White "retire" from CFS research?

Not only did he retire (an aside, it would be interesting to measure the rate of articles published pre and post retirement, and similarly with the number of his talks for insurance companies) but also his retirement has been used to justify rejecting freedom of information requests for the PACE data, which can no longer be accessed without him. In totally unconnected news, White with others is still publishing new articles using the PACE data.
 
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