Amended Cochrane Review: ‘Exercise therapy for chronic fatigue syndrome’ | 03 October 2019


Dr Charles Shepherd, Hon. Medical Adviser, ME Association.

Additional Comment 04 October 2019

Thanks to everyone who has taken the time to look through this revised version of the Cochrane review of exercise therapy in ME/CFS and comment on it. 

The statement from Cochrane

The ME Association is very disappointed by this update of what is supposed to be a ‘gold standard’ review of the safety and efficacy of graded exercise therapy (GET), in particular the way in which it has failed to take proper note of:

  • the deep concerns about the way in which these clinical trials have been carried out – often being unblinded and relying on subjective outcome measures.   
  • the dangers of GET for people with ME/CFS that have been repeatedly expressed by patients, support groups, clinicians and international researchers
  • the fact that GET is not consistent with what we now know about the role of central (brain) and peripheral (muscle) fatigue in ME/CFS.
  • the remarkably consistent evidence on the safety concerns and lack of efficacy of GET that has been collected by the ME Association and other charities over many years.

We are also disappointed to find that the Cochrane review has not followed the high standards of critical analysis that were applied by the US Agency for Healthcare Research and Quality in the production of their Report on the Diagnosis and Management of ME/CFS.

This report noted that:

“…By excluding the three trials using the Oxford (Sharpe, 1991) case definition for inclusion, there would be insufficient evidence of the effectiveness of graded exercise therapy on any outcome … missing from this body of literature are trials evaluating effectiveness of interventions in the treatment of individuals meeting case definitions for … ME/CFS.”
Smith et al (2016) pp. 11-1348.

The report was one of the main reasons that led the US Centres for Disease Control (CDC) to remove GET as a recommended form of treatment for ME/CFS.  

We do not therefore agree with the way in which the evidence base for GET has been analysed by Cochrane. Nor do we agree with the key conclusions about GET that Cochrane has produced:

“Exercise therapy probably has a positive effect on fatigue in adults with CFS compared to usual care or passive therapies. The evidence regarding adverse effects is uncertain. Due to limited evidence it is difficult to draw conclusions about the comparative effectiveness of CBT, adaptive pacing or other interventions.”

However, it is encouraging to note that Cochrane are now willing to work with the patient community and will hopefully produce a more robust review in the future, one that recognises the many concerns and defects that apply to GET. 

I have been in contact with colleagues in other charities, and those in parliament, over the past 48 hours to look at what the next steps should be when it comes to taking this offer forward and will keep you informed.

Reference:
US Agency for Healthcare Research and Quality report on Diagnosis and Treatment of ME/CFS


Original Comment and Cochrane Statement 03 October 2019

Yesterday, Cochrane issued a statement and published an amended version of their previous and controversial review of ‘Exercise therapy for chronic fatigue syndrome’ (see below).

The mission at Cochrane is to, “promote evidence-informed health decision-making by producing high-quality, relevant, accessible systematic reviews and other synthesized research evidence. Our work is internationally recognized as the benchmark for high-quality information about the effectiveness of health care.”

Therefore, it is important that any published reviews are accurate, and the original review of exercise studies in ME/CFS was not.

We are still assessing this latest amendment and will work with colleagues at the CFS/ME Research Collaborative (CMRC) and Forward ME to consider ways in which we can work better with organisations like Cochrane in the future, ensure the evidence-base is more accurately reflected and that it leads to a better understanding of ME/CFS by health professionals.

Cochrane Statement

Today, Cochrane publishes an amended version of the Review, Exercise therapy for chronic fatigue syndrome.’ 

In the last nine months, this Cochrane Review has been modified by the review’s authors and evaluated by independent peer reviewers and editors.

It now places more emphasis on the limited applicability of the evidence to definitions of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) used in the included studies, the long-term effects of exercise on symptoms of fatigue, and acknowledges the limitations of the evidence about harms that may occur.

Cochrane’s Editor-in-Chief, Dr Karla Soares-Weiser, commented on the publication of the review:

“Cochrane recognizes the importance of providing the best available evidence on interventions for ME/CFS to enable patients and clinicians across the world to make well-informed decisions about treatment.

“This amended review is still based on a research question and a set of methods from 2002, and reflects evidence from studies that applied definitions of ME/CFS from the 1990s.

“Having heard different views expressed about the evidence base for this condition, we acknowledge that the publication of this amended review will not resolve all the ongoing questions about this globally important health topic.

The statement from Cochrane

“We have decided, therefore, that a new approach to the publication of evidence in this area is needed; and, today we are committing to the production of a full update of this Cochrane Review, beginning with a comprehensive review of the protocol, which will be developed in consultation with an independent advisory group that we intend to convene.

“This group will involve partners from patient-advocacy groups from different parts of the world who will help us to embed a patient-focused, contemporary perspective on the review question, methods and findings.” 

She added, “By forging better relationships with patients, as well as the groups that represent them and the clinicians who seek to treat them, we can improve the way in which future Cochrane Reviews in this area address important questions and meet patients’ and clinicians’ needs.

“I can confirm that work will begin on this new review at the beginning of 2020 and that we will keep patient groups regularly informed of progress during the subsequent months.”

The review’s conclusions:

“Exercise therapy probably has a positive effect on fatigue in adults with CFS compared to usual care or passive therapies. The evidence regarding adverse effects is uncertain.

“Due to limited evidence it is difficult to draw conclusions about the comparative effectiveness of CBT, adaptive pacing or other interventions.

“All studies were conducted with outpatients diagnosed with 1994 criteria of the Centers for Disease Control and Prevention or the Oxford criteria, or both. Patients diagnosed using other criteria may experience different effects.”

The ME Association

Real People. Real Disease. Real M.E.

We are a national charity working hard to make the UK a better place for people whose lives have been devastated by an often-misunderstood neurological disease.

If you would like to support our efforts and help ensure we can inform, support, advocate and invest in biomedical research, then please donate today.

Just click the image opposite and visit our JustGiving page for one-off donations, to establish a regular payment or to create your own fundraising event.

Or why not join the ME Association as a member and be part of our growing community? For a monthly (or annual) subscription you will also receive our exclusive ME Essential magazine.


ME Association Registered Charity Number 801279