Review ‘Pacing’ for management of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): a systematic review and meta-analysis, 2024, Sanal-Hayes

https://www.tandfonline.com/doi/full/10.1080/21641846.2024.2433390

Review Article
‘Pacing’ for management of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): a systematic review and meta-analysis

Nilihan E.M. Sanal-Hayes1, Marie Mclaughlin2, Jacqueline L. Mair3,4, Jane Ormerod5,David Carless6, Rachel Meach7, Natalie Hilliard8, Joanne Ingram9, NicholasF. Sculthorpe6 and Lawrence D. Hayes 10

1 School of Health and Society, University of Salford, Salford, UK; 2Physical Activity for Health Research Centre, Institute for Sport, P.E. and Health Sciences, University of Edinburgh, Moray House School of Education and Sport, Edinburgh, UK; 3Future Health Technologies, Singapore-ETH Centre, Campus for Research Excellence and Technological Enterprise (CREATE), Singapore; 4 Saw Swee Hock School of Public Health, National University of Singapore, Singapore; 5 Long COVID Scotland, Aberdeen, UK; 6School of Health and Life Sciences, Sport and Physical Activity Research Institute, University of the West of Scotland, Glasgow, UK; 7 Department of Earth Sciences, University of Durham, Durham, UK; 8 Physios for ME, London, UK; 9 School of Education and Social Sciences, University of the West of Scotland, Glasgow, UK; 10Lancaster Medical School, Lancaster University, Lancaster, UK

ABSTRACT
Background
Pacing typically comprises regulating activity to avoid post-exertional neuroimmune exhaustion, the worsening of symptoms after an activity. Yet, the efficacy of pacing to improve symptomology is unclear.

Objective
We aimed to undertake a PRISMA-accordant meta-analysis concerning the effect of pacing on ME/CFS patients’ symptoms.

Data sources
Six electronic databases (PubMed, Scholar, ScienceDirect, Scopus, Web of Science and the Cochrane Central Register of Controlled Trials [CENTRAL]) were searched; and websites MEPedia, Action for ME, and ME Action were also searched for grey literature.

Study selection
Studies (k = 5) selected from the 210 identified included randomised controlled trials (RCTs; k = 2), uncontrolled trials (UCTs; k = 1), intervention case series (k = 1), and sub-analysis of the PACE trial (k = 1), all of which had a pacing component, and an outcome measure reported pre- and post-pacing.

Study appraisal and methods
Three separate meta-analyses were conducted on changes in symptoms using standardised mean differences (SMDs) and random-effects models.

Results
The overall SMD showed pacing improved physical function (k = 4, SMD = 0.15 [95% CI = −0.39, 0.68], p = 0.5951). Pacing improved pain (k = 4, SMD = −0.11 [95% CI = −0.32, 0.10], p = 0.3090). Pacing improved fatigue (k = 4, SMD = −1.09 [95% CI = −2.38, 0.21], p = 0.0998).

Conclusions
Pacing exerted a trivial beneficial effect on physical function and pain. Fatigue was improved with a large effect, which did reach the p < 0.05 level. We cautiously conclude pacing likely exerts some beneficial effects on symptomology, particularly, fatigue, in people with ME/CFS. However, the level of empirical research is insufficient, and more high-quality RCTs are essential to support the NICE guidelines.


Sanal-Hayes, N. E. M., Mclaughlin, M., Mair, J. L., Ormerod, J., Carless, D., Meach, R., … Hayes, L. D. (2024). ‘Pacing’ for management of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): a systematic review and meta-analysis. Fatigue: Biomedicine, Health &amp; Behavior, 1–18. https://doi.org/10.1080/21641846.2024.2433390

 

Science for ME would have been a better source

 

The statement in the abstract for pain, too:

I've only read the abstract but how can you say there is an improvement when the confidence interval includes 0 and there is a p-value of 0.3090?

I also quickly searched to see if the authors included the PACE trial; they do - but the APT arm was not pacing as patients typically practice it.

 

Are they completely clueless about PEM and pacing? AFAIK, pacing is intended to avoid PEM, and avoiding PEM has far more than a trivial effect on symptoms. Does anyone with ME pace to reduce fatigue?

Pacing to maximize what little exercise PWME can do would probably have a trivial beneficial effect on "fatigue" and well-being compared to avoiding physical activity completely, but I don't think that deserves professional coaching or whatever some "expert" would want to get paid for.

 

given that the previous review they did on pacing
see Review - A Scoping Review of Pacing for Management of [ME/CFS]: Lessons Learned for the Long COVID Pandemic, 2023, Sanal-Hayes et al | Science for ME

involved people from Physios4ME and Long Covid Scotland, they should have had a far better understanding. (I haven't looked at the paper but just judging by peoples comments).
@PhysiosforME

so what has changed between these two papers?

 

I'm guessing that the first number (p=0.0998) is for the population of studies (k=4) and the second number (p<0.05) is for the population of patients?

These results seem to make sense to me. Pacing is about minimizing the fatigue/symptoms by avoiding PEM. It's not a treatment to improve the functioning. Whatever the little improvement in physical function they saw probably was incidental from being in PEM less often: it was small and statistically less significant.

 

Good catch. I contacted the author who confirmed that the statement in the abstract is a typo. It should say "which did not reach the p < 0.05 level". He is going to contact the journal to correct it.

 

I wondered about that also. But at least according to ChatGPT, this can happen for various reasons including when there's a small sample size or high variability in the data. So technically, that seems possible.
But to your point, it seems dicey to imply that that is a real effect

 

I don't think these estimates are useful.

The authors have thrown 2 case studies with less than 10 participants and no control group in the mix. This entirely messes up the meta-analysis. The only 2 randomized studies are the PACE trial and this small Belgian study:
https://pubmed.ncbi.nlm.nih.gov/26356665/

In the effect for fatigue, for example you can see that the Antcliff study with only 6 participants reported an effect size bigger than 3.5 standard deviations which seems pretty unreliable. The group of Antcliff also has a different interpretation of pacing, coming from the chronic pain tradition, they see it more like a gentle form of GET.


The review doesn't include this Norwegian RCT (Pinxsterhuis et al. 2015) which tested a 'self-management program based on a self-efficacy theory and the ‘energy envelope’ theory (pacing)'. Unfortunately, it also did not show a favourable effect.
https://journals.sagepub.com/doi/abs/10.1177/0269215515621362

People will probably use this to argue that pacing might be effective but then when critics will look closer it will all fall apart...