Action for M.E.’s current research strategy focuses on collaborative biomedical research, including funding PhD studentships and working closely with patients, clinicians and researchers as part of the UK CFS/M.E. Research Collaborative.
In the past, we have supported all forms of research into M.E. As part of this strategy, the charity was asked to be involved in a large-scale randomised controlled trial, called the PACE trial. Scroll down for more about our previous role in the PACE trial, and our position now.
Two of the treatment approaches test in the PACE trial – cognitive behavioural therapy (CBT), and graded exercise therapy (GET) – are based on the theory that the debility of the disease is the result of deconditioning which is the result of a fear of activity, focusing on symptoms, and unhelpful ways of thinking.
Findings published in 2011 indicated that patients treated with CBT and GET (alongside specialist medical care) experienced moderate improvement in self-rated fatigue and physical function, more than those who used adaptive pacing therapy or specialist medical care alone.
Follow-up results published in 2013 indicated a 59 to 61% improvement, and 22% recovery, for patients who used CBT and/or GET compared to adaptive pacing therapy and/or specialist medical care. It should be noted that "recovery" did not mean that the patient returned to the levels of health and fitness they had before they were diagnosed with M.E.
CBT was defined in the therapist’s manual for the PACE trial as “complex incremental pacing” which involves “elements of simple pacing to stabilise activity, graded increases in activity […] and also directly addresses participant’s beliefs and fears about their symptoms and functioning.”
This type of CBT is based on a theoretical model defined in 2015, which “supposes that unhelpful interpretations of symptoms, fearful beliefs about engaging in activity, and excessive focus on symptoms are central in driving disability and symptom severity. These cognitive responses are associated with unhelpful behavioural patterns, including avoidance of activity or all-or-nothing behaviour – a pattern of excessive resting alternating with pushing too hard or being overactive when well.” An example of a “fear-avoidance belief” is given as follows: “I am afraid that I will make my symptoms worse if I exercise.”
However, studies have demonstrated that even mild exercise can provoke symptoms in some patients – so fears about the consequences of exercise are well-founded.
The aim of the GET approach tested in the PACE trial, as defined in the trial manual, was to: “help the participant to gradually engage and participate in physical activity and aerobic exercise [….].” The approach is based on the assumption that “CFS/ME is perpetuated by deconditioning (lack of fitness), reduced physical strength and altered perception of effort consequent upon reduced physical activity.”
However, the International Alliance for M.E.’s 2018 consensus document on M.E. [LINK] says: “People with ME cannot reproduce their performance on a maximal exercise test 24 hours later, despite showing maximal effort, unlike healthy controls, those who are deconditioned (National Academy of Medicine, 2015), those who have cardiopulmonary diseases (Keller et al, 2014), or those with multiple sclerosis (Hodges et al, 2017). This suggests that the theory underlying CBT and GET studies that the debility of M.E. is a result of deconditioning is flawed.
M.E. is a complex, multi-system disease involving neurological, immunological, autonomic, and energy metabolism impairments. The debility in M.E. is much greater than is seen with deconditioning, and studies have demonstrated that even mild exercise can provoke symptoms – so fears about the consequences of exercise are well-founded.
Serious concerns about the PACE trial are well documented, with repeated questions raised about its methodology, and the reliability of its results. An open letter to The Lancet, signed by more than 100 scientists, clinicians, parliamentarians and patient organisations, including Action for M.E., has been sent three times, asking the journal to reanalyse the trial’s findings.
Concerns about the trial include:
In 2019, the PACE trial authors responded to the re-analysis of trial data referenced above, concluding that, “after carefully reviewing Wilshire et al’s criticisms of the PACE trial findings, we can find no good reason to change its conclusions.”
In a subsequent rejoinder, Carolyn Wilshire and co-author Tom Kindlon highlight that “the PACE authors view the trial protocol as a preliminary plan, subject to honing and improvement as time progresses, whereas we view it as a contract that should not be broken except in extremely unusual circumstances. While the arguments presented by [PACE trial author] Sharpe and colleagues inspire some interesting reflections on the scientific process, they fail to restore confidence in the PACE trial’s conclusions.”
Research into M.E. and/or CFS uses a range of criteria to define the illness being studied. There are in fact more than 20 sets of M.E. and/or CFS case definitions and diagnostic criteria which vary on specificity and sensitivity.
Some do not require hallmark symptoms of M.E. – such as post-exertional malaise – to be present, including the 2005 Reeves, 1994 Fukuda and 1991 Oxford CFS definitions; the latter has, according to a 2014 evidence review by the Agency for Healthcare Research and Quality in the US, a “high risk of including patients who may have an alternate fatiguing illness, or whose illness resolves spontaneously with time” (Smith et al, 2014).
Based on its comparison of definitions, a 2015 National Academy of Medicine report concludes that “the diagnostic criteria for ME have required the presence of specific or different symptoms from those required by the diagnostic criteria for CFS; thus, a diagnosis of CFS is not equivalent to a diagnosis of ME.”
Two of the charity’s previous Chief Executives (prior to 2011) served as independent members of the Trial Steering Committee, and sat on the Trial Management Group. Action for M.E. did not receive any payment for this, and made no contribution to the funding of the trial.
In August 2018, our Chief Executive (since September 2012) said: “By having a role on the Steering Committee and Management Group, there was a de facto endorsement of the use of £5m of research funding to focus on behavioural treatments. Neither I nor the current Board of Trustees would agree to do this now, as reflected by our current research strategy, the focus of which is collaborative biomedical research.
“I am sorry that the charity did not advocate for this considerable level of funding to be invested in biomedical research instead. It was never our intention to contribute to any stigma or misunderstanding about the illness and I sincerely apologise to those who feel that, in not speaking out sooner and more strongly, we have caused harm.
“We will learn from our past mistakes. We will continue to provide practical support to our Supporting Members and others with M.E., to challenge the stigma and neglect they experience, and work with professionals and policy-makers to transform the lives of children, young people and adults with M.E. in the future.”
Action for M.E. does not support any treatment approach:
We fully support treatment approaches which:
A Cochrane review of exercise therapy for CFS identified that “moderate-quality evidence showed exercise therapy was more effective at reducing fatigue compared to ‘passive’ treatment or no treatment. Exercise therapy had a positive effect on people’s daily physical functioning, sleep and self-ratings of overall health.”
In October 2018, Cochrane’s editors added a note that the authors plan to respond to questions concerning the methodology of their review (as opposed to temporarily remove the review from its database entirely, as reported by Reuters news agency).
A 2014 evidence review by the Agency for Healthcare Research and Quality (AHRQ) in the US also found that GET “improved measures of fatigue, function, and clinical global impression of change compared with controls.”
But like Cochrane, that review included studies using the Oxford definition, which may include patients with other fatiguing conditions (see above). In 2016, the AHRQ reanalysed the evidence after excluding the Oxford studies and found insufficient evidence of effectiveness for GET, noting that studies using definitions requiring hallmark criteria such as post-exertional malaise were “blatantly missing.”