Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex and disabling disease that affects many parts of the body, including the brain and muscles, digestive, immune and cardiac systems. ME is classified as a neurological disorder by the World Health Organization.
- Who can develop ME/CFS?
ME/CFS affects people of all ages, ethnicities, and socioeconomic backgrounds.
- 75-80% of people with the condition are female.
- Approximately 25% of people with ME/CFS experience severe symptoms, leaving them housebound or bedbound.
- Studies estimate between 0.4-1% of the population have ME/CFS. In Australia, this means up to 250,000 people are living with ME/CFS.
What causes ME/CFS?
The cause of ME/CFS is not known. Several factors may be involved, including:
- viruses/infection (the most common trigger, but not universal)
- environmental toxins
- physical trauma (such as surgery or car accident)
- genetics (like many other chronic diseases, ME/CFS can run in families, although the specific genes) involved haven’t been identified and more research is needed
- physical, mental or emotional stress
Some people experience sudden onset of ME/CFS while others experience a gradual onset over months or years. These differences are not yet understood.
While there are currently no diagnostic biomarkers or tests for ME/CFS, researchers have found many biological abnormalities in people living with the condition. These include an abnormal physiological response to exercise, altered immune system function, changes in gut bacteria, and impaired energy production.
In the absence of a biomarker, ME/CFS is diagnosed using diagnostic criteria. For accurate diagnosis, criteria used must include post-exertional malaise (PEM). Emerge Australia recommends the use of NAM criteria. Diagnosis should also exclude other possible conditions which could be causing symptoms.
Healthcare practitioners can access a Royal Australian College of General Practitioners (RACGP) accredited online education module with more information on how to accurately diagnose ME/CFS here.
People with ME/CFS experience a wide range of symptoms. These symptoms can vary considerably between patients.
Common symptoms include:
- post-exertional malaise (PEM): symptoms get worse after physical or mental activity
- sleep dysfunction
- widespread pain in muscles or joints
- cognitive difficulties, such as confusion, or problems with concentration and/or memory
- sensitivity to noise and/or light
- light-headedness and/or dizziness
- difficulty with being upright
- gastrointestinal problems such as nausea, abdominal pain, bloating and irritable bowel syndrome
- flu-like symptoms
- problems with temperature regulation
- sensitivities to food, medications and/or chemicals
With no known cure or treatment options, management of ME/CFS aims to reduce symptom severity.
Pacing and rest are the most effective ways to manage symptoms. People with ME/CFS must not push themselves beyond their limits. Doing so puts them at risk of worsening their symptoms, which can be permanent.
Severity of ME/CFS
There are four categories of disability caused by ME/CFS. They provide a guide to the level of impact on symptoms and every day function. However, each person will have a their own symptom and severity profile.
mild: 50% reduction in pre-illness activity
moderate: mostly housebound
severe: mostly bedridden
very severe: totally bedridden and need help with basic functions
Patients may begin with one level of disability, then move to another. For some patients, symptoms can worsen significantly with no known cause. Some patients have a “fluctuating illness” where they have better and worse times. It is unclear why this occurs.
For most people, ME/CFS is a lifelong condition, full recovery (a return to pre-illness functioning) is rare and estimated at less than 10%.