CHRONIC FATIGUE SYNDROME

DEFINITION

Chronic fatigue syndrome (CFS) is a condition that causes extreme tiredness. People with CFS are so tired that they are unable to carry on normal activities for a period of at least six months. They also have other symptoms, such as pain in the joints and muscles, headaches, and sore throat. There is no single known cause for CFS; it appears to result from a number of factors.

DESCRIPTION

Chronic fatigue syndrome is known by many different names. These names include chronic fatigue and immune disorder (CFIDS), myalgic encephalomyelitis (pronounced my-AL-jik en-SEF-uh-lo-MY-uh-LY-tiss), low natural killer cell disease, post-viral syndrome, Epstein-Barr disease, and Yuppie flu. Such names suggest a number of possible causes for CFS. Researchers have not been able to find out which of these causes, or which combination of factors, is responsible for the disease.

Reports of a CFS-like disease date back to 1869. People with the disease were said to have neurasthenia ("nerve weakness," pronounced noor-ess-THEE-nee-uh) or fibromyalgia ("muscle pain," pronounced FI-bro-my-AL-ja). These disorders are now thought to be related to chronic fatigue syndrome.

Another clue to the cause of CFS appeared in the mid-1980s when doctors found antibodies to the Epstein-Barr virus (EBV) in the blood of many people with CFS. Antibodies are produced by the body when it needs to fight off an infection. Some doctors believed that these antibodies meant that chronic fatigue syndrome was caused by the Epstein-Barr virus. It was soon discovered, however, that many people who did not have CFS also had EBV antibodies in their blood. Some scientists now think that EBV may contribute to CFS, but it is not the only factor.

The term Yuppie flu became popular because so many young, middle-class people developed the disease. More detailed studies showed that people of every age, gender, race, and income group can get CFS. The group most at risk for the disease, however, is women aged 25 to 45 years.

Estimating the number of people with CFS is difficult because its symptoms are so similar to those of other diseases. The U.S. Centers for Disease Control and Prevention (CDC) now believe that 4 to 10 out of every 100,000 Americans have CFS. The CFIDS Foundation estimates that about 500,000 adults (0.3 percent of the population) have CFS. These estimates do not include children.

CAUSES

There is no single known cause for chronic fatigue syndrome. Some factors that are thought to be responsible for the disease are:

• Viral infections
• Chemical toxins (poisons)
• Allergies
• Abnormalities in the immune system
• Psychological disorders

Many doctors now believe that CFS is not one illness, but a combination of symptoms caused by several factors. According to one theory, the first step in chronic fatigue syndrome is infection by a virus. About 90 percent of all people have a virus in the herpes family in their bodies. Herpes viruses (see herpes infections entry) cause a number of problems, including cold sores and a painful inflammation of the nerves called shingles (see chickenpox entry).

These viruses are usually dormant (not active) in the body. The viruses can become active again, however, if the body is disturbed in some way. Certain chemicals in the air, for example, can cause the viruses to become active and begin to grow. When that happens, the body's immune system starts to fight off the viral infection. It produces chemicals designed to kill the virus. But these chemicals can cause other effects, too. Those effects are similar to ones observed in people with CFS.

The role of psychological factors in CFS is very controversial. Some think that people who are depressed are more likely to develop CFS. A person's mental state, they believe, may influence the way his or her body works. For example, depression (see depressive disorders entry) might cause dormant viruses to become active again. Other experts disagree with this analysis. They say a person's mental state is more likely to be caused by the disease, rather than being a cause of the disease.

SYMPTOMS

Some people think that chronic fatigue syndrome means only that a person is very tired, but the disease involves much more than that. A person may become so tired that he or she cannot go to work, attend school, or take part in social activities. CFS can also cause problems with sleeping. A person may wake up being just as tired as before he or she went to sleep.

Some CFS patients try to keep up with their normal daily activities, but they may experience "payback." Payback is a state of being even more exhausted than usual. The person may have to stay in bed for days to recover.

Other symptoms of CFS include:

• Muscle pain (myalgia)
• Joint pain (arthralgia)
• Sore throat
• Headache
• Fever and chills
• Tender lymph nodes
• Problems with concentrating
• Memory loss
• Hypotension (low blood pressure)

One of the symptoms of CFS is discoloration of the pharyngeal pillar at the sides of the back of the mouth. (© 1994

Margie Caldwell-Gill

. Reproduced by permission of

Custom Medical Stock Photo

.)

DIAGNOSIS

One step in diagnosing CFS is taking a medical history. Doctors ask patients about their symptoms, about other illnesses they have had, and about medications they are taking. They also conduct a physical examination and may order laboratory tests. They try to eliminate causes of the person's symptoms other than CFS. In the United States, many doctors use a standard created by the CDC for defining CFS. According to this standard, patients have chronic fatigue syndrome if they meet both of the following criteria:

• Chronic (continuous and ongoing) fatigue for at least six months. The condition is not caused by activity and is not relieved by rest. It greatly interferes with the person's job, school, social, or personal activities.
• Four or more of the following symptoms: loss of short-term memory or the ability to concentrate; sore throat; tender lymph nodes; muscle pain; pain in more than one joint without swelling or redness; headaches not previously experienced by the patient; failure of sleep to help the patient feel better; and a feeling of discomfort or tiredness that lasts more than twenty-four hours following exercise. In addition, these symptoms must occur more than once over a six-month period.

TREATMENT

There is no cure for chronic fatigue syndrome, but most symptoms can be treated successfully. The first treatment most doctors recommend is a combination of rest, exercise, and proper diet. The patient is advised to attempt only the most important activities, to avoid over-exerting himself or herself, and to rest whenever necessary. A moderate amount of exercise is important, but too much exercise can make the disease worse. Counseling and stress reduction (learning how to better handle the pressures of everyday life) can also be helpful.

Many medications, nutritional supplements (like vitamins and minerals), and herbal preparations have been used to treat CFS. Doctors and patients should work together to arrange the best plan for each individual.

Drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (pronounced i-byoo-PRO-fuhn) and naproxen, can be used to relieve pain and reduce fever. Antidepressants can be used to help patients relax and feel less depressed. Antianxiety drugs, such as benzodiazepines (pronounced benzo-die-A-zuh-peenz), are prescribed for people with anxiety that has lasted for at least six months.

A number of other drugs are being tested for use with CFS patients. These include fludrocortisone (pronounced FLOO-dro-KOR-tih-zone, trade name Florinef) and beta-adrenergic drugs, such as atenolol (pronounced uh-TEN-uh-lol) and propranolol (pronounced pro-PRAN-uh-lol), to control blood pressure, and gamma globulin (pronounced GA-muh GLAH-byu-lun) and ampligen (pronounced AM-plih-jen), to help fight off infections.

Alternative Treatment

Nutritional supplements such as vitamins A, B₁₂, C, and E, as well as some minerals, are used to treat CFS. These supplements are thought to improve the immune system and improve mental functions. Some CFS patients report improvement after using certain herbal medicines, such as echinacea (pronounced ek-i-NAY-see-uh), garlic, ginseng, ginkgo, evening primrose oil, shiitake mushroom extract, and borage seed oil.

Other therapies that have been tried in the treatment of CFS include meditation, acupuncture (a Chinese therapy treatment involving the puncturing of small needles into the body), and yoga. These therapies sometimes help people to relax and get more rest. They may also help reduce depression and anxiety.

PROGNOSIS

The course of CFS varies widely for different people. Some patients get progressively worse over time. Others improve slowly. Some individuals have periods of illness that alternate with periods of good health. Many people never fully recover from CFS. Most patients, however, find some relief by following a treatment plan that includes adequate rest, nutrition, exercise, and other therapies.

PREVENTION

There are currently no recommended ways of preventing CFS.

FOR MORE INFORMATION

Books

Hoffman, Ronald L. Tired All the Time. New York: Poseidon Press, 1993.

Johnson, Hillary. Osler's Web: Inside the Labyrinth of the Chronic Fatigue Syndrome Epidemic. New York: Crown Publishers, 1996.

Periodicals

Weiss, Rick. "A Cure for Chronic Fatigue Syndrome?" The Nurse Practitioner (July 1997): pp. 30–40.

Organizations

American Association for Chronic Fatigue Syndrome. 7 Van Buren Street, Albany, NY 12206. (518) 435–1765.

The CFIDS Association. Community Health Services. PO Box 220398, Charlotte, NC 28222–0398. (704) 362–2343.

The National CFS Association. 919 Scott Avenue, Kansas City, KS 66105. (913) 321–2278.

The National CFIDS Foundation. 103 Aletha Road, Needham, MA 02192. (781) 449–3535. http://www.cfidsfoundation.org.

Web sites

Centers for Disease Control and Prevention. "The Facts about Chronic Fatigue Syndrome." [Online] http://www.cdc.gov/ncidod/diseases. (accessed on October 15, 1999).

National Institutes of Health, Public Service Resources. "Chronic Fatigue Syndrome." [Online] http://www.niaid.nih.gov/publications. (accessed on October 15, 1999).