Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME-CFS): good practice statement

1. Introduction

"ME was [is] known to run a chronic course and patients had disabilities due to persistent symptoms of pain, fatigue and loss of endurance to normal physical activities with conspicuous deterioration of symptoms after exercise (post exertional malaise)." Scottish Short Life Working Group.

There has been much national and international debate over the terminology for this illness. ME-CFS is an illness characterised by persistent and fluctuating symptoms of fatigue, pain and loss of endurance to normal activities associated with conspicuous deterioration after exercise. It has been referred to as ME (Myalgic Encephalomyelitis/Encephalitis/Encephalopathy), CFS (Chronic Fatigue Syndrome) and sometimes as PVFS (Post Viral Fatigue Syndrome).

It causes significant ill health and disability in a substantial number of adults, young people and children. It can affect both sexes, at any age, from any ethnic group. Epidemiological evidence is lacking in Scotland but a population prevalence of at least 0.2-0.4% is widely accepted and over 20,000 people in Scotland may be affected. It is more common in women and in patients aged from 35-55 years. It has characteristic features which can be variable among patients. It is also variable in its duration and severity, with a substantial number severely affected (see Section 5).

ME-CFS is therefore generally recognised as being heterogeneous and may consist of a number of subtypes, but these have not yet been specifically categorised. It follows that care of patients with ME-CFS must be specifically and carefully tailored to the symptoms, needs and circumstances of the individual patient.

At present, the diagnosis of ME-CFS remains clinical, based on recognising specific symptom patterns. Currently there are no specific tests available to confirm the presence of the illness. There are many conditions that can present with some symptoms that are common to ME-CFS, but differential diagnosis must be carefully applied and should enable ME-CFS to be accurately identified. Patients should be encouraged about establishing the correct diagnosis and may need to be reassured that listing those other conditions for the purposes of differentiation does not imply any judgment about the nature of ME-CFS.

The World Health Organisation (WHO) has classified Benign Myalgic Encephalomyelitis (ME) including post viral fatigue syndrome, under disorders of the nervous system (neurological diseases) – ICD 10 G93.3.

This particular WHO classification underpins this present guidance. (Note: the equivalent Read code to ICD 10 G93.3 is F286.) A number of other attempts have been made to define the illness, none of which are universally accepted. The Report of the 2002 Chief Medical Officer (England) CFS/ME Working Group called for a consensus on terminology and definition, and while awaiting this, suggested that a composite term should be used and that it is considered as one illness or a spectrum of disease. The composite term ME-CFS is used in this guidance, which is also used by the Scottish Public Health Network's Health Care Needs Assessment of Services for people living with ME-CFS.^[1]

The crucial point is that the NHS recognises that ME-CFS is real, associated with altered neural functioning and causes significant and in some cases, profound disability. As such, it places a substantial burden on people with the illness, their families and carers and on society.

The prognosis is extremely variable. Most patients have a fluctuating course of illness with some people recovering, or improving significantly, in less than two years, while others remain ill for several decades. Some patients will have a relapsing remitting course of illness while others do not experience remission.

ME-CFS causes a range of symptoms and it is necessary to adopt a holistic approach to care and symptom control having regard not only for the illness and its treatment but also for the impact of the illness on the patient, their carers, family and on work and social life.

The normal general practice principles of empathetic listening, mutual respect and shared decision making between a person with ME-CFS and health care professionals are essential during all phases of care in the NHS. People with ME-CFS have a right to refuse or withdraw from any component of their care plan without affecting other aspects of their care, or future choices about care.

During the early stages, particularly with acute onset, possibly triggered by a recent infection, the clinical presentation may involve symptoms such as hypersomnia and severe fatigue. These may fluctuate in severity and nature, requiring careful clinical management and appropriate review.

There is also the need for early and accurate diagnosis where possible, with consideration of making the provisional diagnosis by three to four months into the illness. Relevant investigations should be completed in this timeframe and symptom management should begin. GPs should be able to help alleviate symptoms in most patients with ME-CFS, as with many other chronic conditions. Shared care with specialists, for diagnosis and/or development of management plan, will help with problems that are complex, severe and prolonged. Further assistance and sources of help, including advice on work and welfare benefits and the sharing of patient experiences, is provided in Section 8 and Appendix 1.

In conclusion, the diagnosis of ME-CFS remains clinical, based primarily on symptom recognition. In the absence of a specific diagnostic test or tests, it is vitally important that Scotland develops effective mechanisms for bringing together researchers, practising clinicians and people with ME-CFS to drive forward the optimal care, research and development agenda. This will in turn, lead to improved clinical practice in the NHS in Scotland.

Going forward – in all of our endeavours for supporting people with ME-CFS and their carers, there has to be a sense of positivity, pulling together and of rising to the occasion – "we owe it to our patients and to our professionalism".