Editorials
Updated NICE guidance on chronic fatigue syndrome
BMJ 2020; 371
- Lynne Turner-Stokes, Northwick Park professor of rehabilitation1,
- Derick T Wade, professor of neurological rehabilitation
- Correspondence to: L Turner-Stokes lynne.turner-stokes@nhs.net
Why standard approaches to evidence evaluation must change
An update of the National Institute for Health and Care Excellence (NICE) guidelines for diagnosis and management of chronic fatigue syndrome (also known as myalgic encephalomyelitis (CFS/ME)) is open for consultation, closing on 22 December.
1 In contrast to the 2007 guidelines,
2 which recommended interventions such as cognitive behavioural therapy and graded exercise therapy for people with mild or moderate CFS/ME, the update cites a “lack of evidence for the effectiveness of these interventions” despite the overall positive results of randomised evidence published since 2007.
345
Instead, the new draft emphasises the potential harms of exercise, based on qualitative evidence provided by a small number of service users, and the balance has shifted towards helping patients to adjust to the long term debilitating effects of CFS/ME. It also shortens the timescale for diagnosis of CFS/ME, to include patients with symptoms persisting for just 12 weeks, even though the criteria developers recommend six months.
6 This change in attitude away from rehabilitative interventions is worrying, as many patients do recover from chronic fatigue symptoms. Importantly, as the covid-19 pandemic shows, although fatigue, post-exertional malaise, and other symptoms may persist for weeks or months after viral illness, symptoms can improve over time with appropriate support and rehabilitation. The proposed update has therefore provoked a highly polarised response.
One fundamental problem is the NICE approach to evaluating evidence. NICE uses the GRADE system, which sets out a series of isolated questions using the PICO (patient, intervention, comparison, and outcome) framework and then rates the quality of research evidence for each recommendation. Within the hierarchy, evidence from randomised trials starts high but is downgraded if trials fail to meet strict quality criteria.
Many of these criteria were formulated for evaluating drug trials and focus on design features that are poorly applicable to complex interventions such as rehabilitation for people with CFS/ME or other complex conditions (
box 1). Designs other than randomised trials are considered low quality, however well executed. Taken together, these challenges result in “low” or “very low” quality ratings for evidence from even the best studies of complex interventions.
Box 1
Quality criteria that are poorly applicable to complex conditions
- Risk of bias—Double blinding is impossible as patients can never be truly blinded to interventions that require their active participation
- Precision—Patient populations are relatively small and heterogeneous in complex conditions. Confidence intervals are consequently wide, so studies are downgraded for “imprecision”
- Directness—This requires the intervention to be evaluated in the population of interest. Even the most definitive studies of complex conditions may be downgraded as “indirect” if the diagnostic criteria that were current at the time of the trial have been superseded (even if only marginally different)
- Consistency—Interventions must be fully described and replicated in all participants. While simple for a drug, this is neither possible nor appropriate for rehabilitation interventions, which should always be individually tailored in full collaboration with each patient
- Objective outcome measures—This favours physiological or standardised performance measures. Patient-reported outcomes such as pain, distress, and function in their daily lives are downgraded as “subjective” despite their widely accepted clinical importance.
Patients with CFS/ME are not a homogeneous group.
7 As is the case with other complex conditions, each person’s experience is unique, and the intervention(s) needed will depend on their particular symptoms, circumstances, and preferences. Some people recover completely, but for others CFS/ME is a relapsing or long term condition requiring ongoing professional support. Here, goals for intervention may be to manage and prevent deterioration as well as supporting adjustment. One-off, short term interventions are rarely the answer.
Holistic rehabilitation
Integrated rehabilitation takes a holistic approach, providing an individually tailored programme focused on personal goals agreed between the patient and the rehabilitation team.
8 For patients with CFS/ME, such programmes combine a range of physical, cognitive, and psychological approaches depending on patients’ preferences and priorities. These may include elements of cognitive behavioural therapy, exercise, pacing, or endurance building. Active engagement by patients and their families is essential, and is more likely if patients have been fully involved in the choice of interventions, which are then incorporated into everyday activities.
Although this is basic common sense, current NICE methods would discount any randomised controlled trials using this approach, citing risk of bias, inconsistency, imprecision, and subjective outcomes. Faced with this rigid structure, trialists have been forced to break down rehabilitation into separate component parts that often bear scant resemblance to clinical practice. Trials in people with CFS/ME typically allocate participants to one or more isolated interventions—such as cognitive behavioural therapy, graded exercise therapy, or adaptive pacing—regardless of their actual needs or preferences.
Holistic integrated rehabilitation supplies the equivalent of a well tailored suit, fitted to the individual patient, with room for adjustment as needs change. It is more expensive in the first instance, but there is strong evidence for the effectiveness and cost efficiency of such bespoke programmes in other complex conditions.
910 By failing to understand the fundamental principles of good medical practice in these complex, multifactorial conditions, NICE methods continue to foster a fragmented approach in which some patients are effectively provided with trousers only, and others with just the jacket—typically on a short term (“hire”) basis. Small wonder that the trials have overall success rates of under 50%, although an important minority of patients do improve.
It is easy to see why people with CFS/ME might be upset about the research evidence underpinning their management options. Often disbelieved by clinicians, many find themselves fobbed off with a prescription for gym membership or a course of exercise classes under the pretext of evidence based practice. Offered in this form, it is unsurprising that the general concept of exercise is seen as harmful.
However, instead of recommending fully integrated rehabilitation with patients and clinicians working in partnership, NICE has chosen simply to downplay the evidence supporting graded exercise therapy and cognitive behaviour therapy, with the worrying consequence that these interventions will not be available in the future, even to those who would benefit. The updated guideline could have unintended adverse consequences for large numbers of patients, especially if used in the management of long covid.
Complex interventions for complex conditions are becoming the dominant healthcare reality, and if NICE is to serve any useful purpose in this arena, it needs to develop a more appropriate way to evaluate evidence. Existing evidence shows that some patients with CFS/ME do benefit from various components of rehabilitation, and our first priorities should be to identify who is likely to respond to which intervention(s), and to ensure that each patient’s needs are met.
This can only be achieved through systematic collection and longitudinal analysis of real life clinical data on a large scale. Rehabilitation prescriptions are one way forward. These are individualised records of patients’ rehabilitation needs and the plans to provide for them, alongside centralised data collection to track how well those needs are met over time.
11 Proof of principle already exists within the major trauma pathways,
12 and is now being extended into other areas, including long term care. Such long term observational research is no less important than randomised trials, and NICE should consider using alternative appraisal systems that are independent of trial design, providing a better fit for this kind of evidence.
13
Above all, it is time to recognise that person centred rehabilitation, delivered over an appropriate period, is much more likely to provide tangible benefits than the piecemeal, disjointed efforts that continue to be fostered by the current NICE guideline methods.
Footnotes