As there is no specific single test to detect M.E., diagnosis is made after other possible known causes for symptoms have been excluded. This should be a positive clinical diagnosis made on a well-characterised constellation of symptoms.
Our Newly diagnosed with M.E./CFS booklet is endorsed by the National Institute for Health and Care Excellence (NICE) and provides information and advice about the diagnosis, symptoms and management of M.E. There is also guidance to help patients be an active partner in their own care, suggestions for questions to ask GPs, and information about existing guidelines for health professionals. We advise all healthcare professionals who need information on M.E. to begin by downloading and reading this free resource.
Further guidance for GPs in Scotland, building on the SGPS, is provided in our booklet, Managing M.E./CFS: a guide for GPs in Scotland.
The NICE guideline for M.E. (undergoing essential updates, though this process is on hold due to the Coronavirus pandemic) and the Scottish Good Practice Statement on M.E. detail the signs and symptoms that characterise M.E., and tests that should be undertaken. Diagnosis should be made after other possible diagnoses have been excluded and the symptoms have persisted for four months in an adult or three months in a child or young person.
Because we don’t yet understand the biology of M.E., there are no targeted treatments that work for the majority. This differentiates M.E. from other conditions where better understood biomarkers can offer clearer treatment pathways and protocols. So a treatment approach that one patient finds effective may or may not have a different impact on someone else with the illness.
The NICE guideline also states that a diagnosis of M.E. “should be reconsidered if none of the following key features are present:
- post-exertional fatigue or malaise
- cognitive difficulties
- sleep disturbance
- chronic pain.”
Action for M.E.’s 2019 Big Survey found that:
- 12% of people with M.E. had been symptomatic for three years or less
- 27% for four years to nine years
- 61% for 10 years or more.
Results also indicated that, despite the NICE guideline for M.E. stating that symptoms should be present for four months before diagnosis is made, a significant number of people with M.E. wait much longer, potentially delaying access to specialist care and support. Our survey found that:
- roughly 28% of adults are receiving a diagnosis after four months.
- 45% of people are waiting more than a year.
The prognosis varies, possibly because of sub-types or phenotypes, and different definitions of recovery. A Chief Medical Officer’s report published in 2002 concluded that most patients show improvement over time, a substantial number have a fluctuating course of illness with periods of remission and relapse, but that a significant minority become severely ill and permanently disabled.
A review of published studies reported recovery rates of 8–63% (median 40%), with full recovery being rare (5–10% achieving total remission). The prognosis in children and young people is more optimistic.