Myalgic encephalomyelitis/chronic fatigue syndrome
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating long-term medical condition. People with ME/CFS experience lengthy flare-ups of the illness following relatively minor physical or mental activity. This is known as post-exertional malaise (PEM) and is the hallmark symptom of the illness. Other core symptoms are a greatly reduced ability to do tasks that were previously routine, severe fatigue, and sleep disturbances. The baseline fatigue in ME/CFS does not improve much with rest. Orthostatic intolerance, memory and concentration problems, and chronic pain are common. About a quarter of people with ME/CFS are severely affected and unable to leave their bed or home.: 3
| Myalgic encephalomyelitis/chronic fatigue syndrome | |
|---|---|
| Other names | Chronic fatigue syndrome (CFS), myalgic encephalomyelitis (ME), post-viral fatigue syndrome (PVFS), chronic fatigue immune dysfunction syndrome (CFIDS), systemic exertion intolerance disease (SEID), others: 20 |
| Chart of the symptoms of ME/CFS according to various definitions | |
| Specialty | Rheumatology, rehabilitation medicine, endocrinology, Infectious disease, neurology, immunology, internal medicine, paediatrics, other specialists in ME/CFS |
| Symptoms | Worsening of symptoms with activity, long-term fatigue, others |
| Usual onset | Peaks at 10–19 and 30–39 years old |
| Duration | Long-term |
| Causes | Unknown |
| Risk factors | Female sex, virus and bacterial infections, blood relatives with the illness, major injury, bodily response to psychological stress and others: 1–2 |
| Diagnostic method | Based on symptoms |
| Treatment | Symptomatic |
| Prevalence | About 0.68 to 1% globally |
The root cause(s) of the disease are unknown and the mechanisms are not fully understood. ME/CFS often starts after a flu-like infection, for instance after infectious mononucleosis. In some people, physical trauma or psychological stress may also act as a trigger.: 10 A genetic component is suspected, as ME/CFS can run in families. ME/CFS is associated with changes in the nervous and immune system, energy metabolism and hormone production. Diagnosis is based on symptoms because no confirmed diagnostic test is available.
The course of ME/CFS is hard to predict. The illness may improve, worsen, or fluctuate in severity, but full recovery is rare. Treatment is aimed at relieving symptoms, as no therapies or medications are approved to treat the condition. Pacing and activity management can help prevent flare-ups. Counseling may aid in coping with the illness.
About 1% of patients at primary care clinics have ME/CFS. Estimates vary widely because studies have used different definitions. ME/CFS occurs 1.5 to 2 times as often in women as in men. It most commonly affects adults between 40 and 60 years old, but can occur at other ages, including childhood. ME/CFS significantly reduces health, happiness and productivity, and can cause loneliness and alienation.
People with ME/CFS often face stigma in healthcare settings, and doctors may have trouble managing an illness that lacks a clear cause or treatment.: 30 Historical research funding for ME/CFS has been far below that of comparable diseases. There is controversy over many aspects of the condition, including the name, cause and potential treatments.