Chronic fatigue syndrome (CFS) is a debilitating condition marked by profound, long-lasting fatigue and multiple other symptoms such as joint pain and muscle pain. A syndrome is not a disease but rather a cluster of symptoms. CFS often starts abruptly but can develop gradually. The cause is unknown, but CFS is believed not to be contagious or fatal.
People with chronic fatigue syndrome experience disruption in one or more aspects of their life, such as work, self-care and family life. The name is misleading because it does not indicate the severity of the disabling symptoms, according to the National Women’s Health Resources Center and CFS support groups.
The syndrome has been controversial, with disagreements over diagnostic criteria, treatment and even the existence of CFS. Patients have sometimes been described disparagingly as having “yuppie flu,” faking a condition or being mentally ill. However, recent research released by the U.S. Centers for Disease Control and Prevention (CDC) supports CFS as having a biological basis. Some research has suggested genetics plays a role.
The U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) emphasizes that chronic fatigue syndrome is not the same thing as chronic fatigue, which is also a symptom of fibromyalgia, rheumatoid arthritis, systemic lupus erythematosus (SLE) and other conditions.
Chronic fatigue syndrome can strike anyone but is most common in young and middle-age women. It is generally estimated that about 900,000 Americans have a CFS-like condition, according to the National Women’s Health Resources Center. The CDC puts the figure at roughly 500,000. The International Association for Chronic Fatigue Syndrome estimates that 500,000 to 800,000 Americans have CFS, 85 percent of them still undiagnosed. According to the Chronic Fatigue and Immune Dysfunction Syndrome Association of America, CFS is much more common in women than better-known conditions such as HIV infection or lung cancer.
Chronic fatigue syndrome was named in the 1980s, but the condition or similar disorders have been known by other names for centuries. It used to be known as chronic Epstein-Barr because it was once blamed on the Epstein-Barr virus. Current alternate terms for CFS include chronic fatigue and immune dysfunction syndrome (CFIDS) and postviral fatigue syndrome.
Scientists do not know what causes chronic fatigue syndrome (CFS). It was once thought to be caused by infection with Epstein-Barr virus (EBV) or another virus and used to be referred to as chronic EBV. However, it is now believed that CFS cannot result from infection with any one known human pathogen, though infectious agents may play a role in some cases of CFS, according to the National Center for Infectious Diseases.
Some CFS patients have signs of autoimmune diseases, such as autoantibodies (immune system proteins that mistakenly attack the body’s healthy tissues). However, tissue damage characteristic of autoimmune disorders has not been described in people with CFS.
Several studies indicate that the central nervous system has a role in CFS. For example, CNS dysfunction may impair the immune system or inhibit the release of pain-relieving hormones such as cortisol. More research will be needed to establish a link.
In addition to researching possible roles of the immune and nervous systems, scientists are studying other possible factors, including genetic predisposition, stress, metabolic disturbances, hormones and environment.
According to the National Women’s Health Resource Center, one-third of cases follow a symptomatic respiratory, stomach or other acute infection, and other cases develop after physical or emotional trauma such as surgery, a car accident or the death of a loved one. Some research has linked a sedentary lifestyle to increased risk of CFS.
The primary known risk factors for chronic fatigue syndrome are sex and age. Three to four times as many women as men have CFS, and the condition seems to be most common in women in their 40s, according to the National Women’s Health Resource Center. The condition can occur at any age and has also been described in young adults and adolescents.
The primary indicator of chronic fatigue syndrome (CFS) is severe fatigue that has lasted for months. Individuals often feel exhausted even after mild or moderate physical activity. Other common signs and symptoms include:
- Difficulties with memory or concentration
- Muscle or joint pain
- Insomnia or other problems with sleep
- Sore throat
- Tender, painful lymph nodes
- Stress, anxiety, depression or panic
Other symptoms that individuals may experience include:
- Abdominal pain or bloating
- Chest pain, irregular heartbeat or shortness of breath
- Dry eyes and mouth
- Ear pain
- Intolerance for alcohol
- Jaw pain such as TMJ disorder
- Morning stiffness
- Night sweats
- Unexplained weight loss
Because these signs and symptoms can also point to many other conditions, it is important to see a physician for diagnosis.
A physician seeing a patient who may have chronic fatigue syndrome (CFS) will typically review the patient's medical history and perform a physical examination focusing on the joints,
lymph nodes and other body parts affected. Physicians often assess mental status by asking questions or using an oral or written test.
Blood tests and urine tests may be ordered to identify or rule out other possible sources of fatigue, such as anemia (insufficient number of red blood cells).
Tests suggested by the U.S. Centers for Disease Control and Prevention (CDC) for screening patients for chronic fatigue syndrome include:
- Complete blood count and electrolytes, to indicate many possible underlying diseases
- Sedimentation rate, to detect inflammation
- Waste product tests, to detect kidney disease and other disorders
- Alanine aminotransferase (ALT) and globulin, to detect liver diseases
- Albumin, to detect malnutrition, liver disease, kidney disease or other problems
- Calcium, to detect cancer and other disorders
- Phosphorus, to detect kidney failure and other disorders
- Glucose, to detect diabetes
- Total protein, to detect dehydration
- Thyroid stimulating hormone (TSH), to detect thyroid disorders
- Urinalysis, to detect kidney diseases, systemic lupus erythematosus (SLE) and many other disorders
More than 90 percent of patients with severe fatigue will have normal results for the above lab tests, according to the CDC.
Depending on the symptoms presented by the individual, imaging tests such as x-rays or CAT scan (computed axial tomography) may also be ordered. The physician may recommend a tilt table test to detect the low blood pressure (neurally mediated hypotension) that some CFS patients have.
Patients must meet two criteria to be diagnosed with chronic fatigue syndrome, according to the U.S. National Institutes of Health (NIH) and international CFS experts:
- Have severe, chronic fatigue for six months for more, with other known causes ruled out by clinical diagnosis
- Have four or more of the following symptoms for the previous six months or longer:
- Substantially impaired concentration or short-term memory
- Sore throat
- Tenderness in the lymph nodes of the armpits or neck
- Muscle pain
- Multiple joint pains without swelling or redness
- Headaches of a new type, pattern or severity
- Lack of refreshment from sleep
- Discomfort for more than 24 hours after exertion
A diagnosis of CFS is a diagnosis of exclusion, meaning other medical conditions must be ruled out. CFS is diagnosed if there is no other explanation for the fatigue and if the other symptoms did not develop before the fatigue, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). Thus diagnosis may be a time-consuming process for the patient and may become frustrating.
It should be noted that some physicians, researchers and facilities may accept a co-diagnosis of CFS in people who have other illnesses that involve chronic fatigue.
However, the NIH and other U.S. government health agencies exclude these conditions, unless the condition has been treated adequately and no longer explains the fatigue and other symptoms.
- Chronic mononucleosis
- Autoimmune diseases such as SLE
- Glandular and hormonal disorders such as hypothyroidism
- Lyme disease
- Sleep apnea and narcolepsy
- Gulf War syndrome
- Chemical sensitivities
- TMJ disorder
- Depression and other mental disorders
- Alcohol and drug abuse
- Reactions to medications
Scientists are trying to develop diagnostic techniques specific to chronic fatigue syndrome. Spinal taps have revealed a group of proteins found in the cerebrospinal fluid of people with CFS but not in healthy individuals. These findings are not sensitive or specific at this time but could eventually lead to a test that allows earlier diagnosis and treatment.
The CDC advises against trying to diagnose CFS with experimental serologic and immunologic tests, such as retrovirus tests. Testing for Epstein-Barr virus (EBV) was once used in diagnosing chronic fatigue syndrome because EBV was considered a likely cause, but scientists have learned that many cases of CFS have no link to this virus.
There is no known cure for chronic fatigue syndrome (CFS). Treatment focuses on relieving symptoms and helping the patient adapt. The treatment plan developed with the physician can vary greatly, depending on the individual’s needs, symptoms and general health. The treatment plan may include:
It is especially important for CFS patients to get their healthcare provider’s approval before starting or changing an exercise program. Regular participation in mild to moderate physical activity prevents deconditioning, promotes sleep, improves the ability to cope and reduces the risk of other health problems, such as heart disease. However, it is important for patients to pace themselves, rest as needed and avoid overexertion and fatigue. Steady, gradual exercise is typically recommended. Patients may be referred to physical therapy for help in creating an exercise program that works for them.
Educating the patient about the disease process, possible outcomes, various therapies, expectations and treatment plans has been seen to be beneficial. Talking to other patients with the same condition or enrolling in a group program has also been helpful, as the diagnosis process and treatment process is frustrating for patients.
This treatment has been shown to help CFS patients cope and to allow increased activities without increased symptoms, according to the U.S. Centers for Disease Control and Prevention (CDC).
Classes, support groups and other methods can help CFS patients reduce stress and insomnia, which can worsen their condition. Techniques such as biofeedback may help. Massage therapy may offer relief.
Sleep centers may be able to treat the sleep disorders that are common with CFS.
Techniques such as task simplification, time management and use of adaptive equipment can help individuals cope with CFS. Occupational therapy can offer instruction in such methods.
A general healthy eating plan (e.g., rich in vegetables, whole grains and lean protein, low in animal fats and sugar) can promote endurance in people with chronic fatigue syndrome. The CDC cautions against the many unproven dietary supplements and herbal products that have been touted as beneficial for CFS. Some of these products, including comfrey and high-dose ginseng, have been shown to be harmful, the agency reports.
Several small-scale studies have found acupuncture useful in easing symptoms of CFS. Acupressure may also provide relief for some.
There is no known way to prevent chronic fatigue syndrome, but people can avoid exacerbations by practice good habits (exercise, diet, sleep) as described above.
In addition, avoiding excess standing and heat may help. Many people with CFS experience lightheadedness or increased fatigue if they stand for long periods or spend time in warm places, according to the CDC. Such individuals are advised to avoid triggers such as long showers, saunas and tasks that require prolonged standing.
Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about chronic fatigue syndrome (CFS):
- How do fatigue, chronic fatigue and chronic fatigue syndrome differ?
- Could CFS explain my symptoms?
- What other conditions could be causing my symptoms?
- If I have fibromyalgia or a similar condition, could I also have CFS?
- What tests for CFS might I undergo, and what do these tests involve?
- What are my treatment options, and which do you recommend?
- What are the risks and benefits of any recommended medications?
- Can cognitive behavioral therapy, stress management, physical therapy, occupational therapy, biofeedback, massage therapy or acupuncture help?
- What is the expected course of my CFS?
- How can I prevent exacerbations or flare-ups?
- Does the latest research about CFS show anything that could pertain to my case?