CFIDS: THE BASICS

WHAT IS CFIDS?

Chronic fatigue immune dysfunction syndrome (CFIDS) is a complex, debilitating, often disabling illness that affects multiple body systems.  It is characterized by incapacitating fatigue (experienced as profound exhaustion and extremely poor stamina), neurological and neurocognitive symptoms, neuroendocrine and autonomic dysfunction, and immunological abnormalities, among other symptoms.  CFIDS can be severely debilitating and can last for many years.  CFIDS is often misdiagnosed because it is frequently unrecognized and can resemble other disorders including mononucleosis, multiple sclerosis (MS), fibromyalgia (FM), Lyme disease, post-polio syndrome and autoimmune diseases such as lupus.  CFIDS is also known as chronic fatigue syndrome (CFS) and myalgic encephalomyelitis (ME).

HOW IS CFIDS DIAGNOSED?

Despite a decade of research, there is still no definitive diagnostic test for CFIDS.  A research and clinical definition for CFIDS was developed by an international group of researchers led by scientists at the Centers for Disease Control & Prevention (CDC).  This case definition was published in the December 15, 1994 issue of the Annals of Internal Medicine.  Diagnosing CFIDS requires a thorough medical history, physical and mental status examinations and laboratory tests to identify underlying or contributing conditions that require treatment.  Clinically evaluated, unexplained chronic fatigue cases can be classified as chronic fatigue syndrome if the patient meets both the following criteria:

    1. Clinically evaluated, unexplained persistent or relapsing chronic fatigue that is of new or definite onset (i.e., not lifelong), is not the result of ongoing exertion, is not substantially alleviated by rest and results in substantial reduction in previous levels of occupational, educational, social or personal activities.

    2. The concurrent occurrence of four or more of the following symptoms: substantial impairment in short-term memory or concentration; sore throat; tender lymph nodes; muscle pain; multi-joint pain without joint swelling or redness; headaches of a new type, pattern or severity; unrefreshing sleep; and post-exertional malaise lasting more than 24 hours.  These symptoms must have persisted or recurred during six or more consecutive months of illness and must not have pre-dated the fatigue.

    The case definition describes several medical conditions which, when present, exclude a patient from a diagnosis of CFIDS.  Among these conditions is a past or current diagnosis of a major depressive disorder with psychotic or melancholic features.

WHAT ARE OTHER COMMON SYMPTOMS?

Persons with CFIDS (PWCs) have symptoms that vary from person to person and fluctuate in severity.  Specific symptoms may come and go, complicating treatment and the PWC's ability to cope with the illness.  Most symptoms are invisible, which makes it difficult for others to understand the vast array of debilitating symptoms that PWCs have.  The eight primary symptoms described in the CDC's case definition are listed above.  Other symptoms common to CFIDS are listed below (please note that most PWCs do not have all these symptoms and that they are not required for diagnosis).  PWCs have cognitive problems in addition to difficulties with concentration and short-term memory (such as word-finding difficulties, inability to comprehend/retain what is read, inability to calculate numbers and impairment of speech and/or reasoning).  They also have visual disturbances (blurring, sensitivity to light, eye pain, need for frequent prescription changes); chills and night sweats; shortness of breath; dizziness and balance problems; sensitivity to heat and/or cold; alcohol intolerance; irregular heartbeat; irritable bowel (abdominal pain, diarrhea, constipation); low-grade fever or low body temperature; numbness, tingling and/or burning sensations in the face or extremities; dryness of the mouth and eyes (sicca syndrome); menstrual problems including PMS and endometriosis; chest pains; rashes; ringing in the ears (tinnitus); allergies and sensitivities to noise/sound, odors, chemicals and medications; weight changes without changes in diet; light-headedness; feeling in a fog; fainting; muscle twitching; and seizures.  Some PWC's may experience secondary depression, irritability, anxiety, panic attacks or mood swings).

HOW IS CFIDS TREATED?

Treatment for CFIDS is intended primarily to relieve specific symptoms.  Treatment must be carefully tailored to meet the needs of each patient.  Sleep disorders, pain, gastrointestinal difficulties, and allergies are some of the symptoms which physicians commonly attempt to relieve through the use of prescription and over-the-counter medications.  Persons with this illness may have unusual responses to medications, so extremely low dosages should be tried first and gradually increased as appropriate.  Lifestyle changes, including increased rest, reduced stress, dietary restrictions, nutritional supplementation and minimal exercise also are frequently recommended.  Supportive therapy, such as counseling, can also help to identify and develop effective coping strategies.  Researchers and clinicians specializing in CFIDS use therapies that attempt to alter the mechanism or nature of the disease.

HOW MANY PEOPLE HAVE CFIDS?

A study by DePaul University estimates CFIDS at approximately 422 per 100,000 persons in the U.S.  This means as many as 800,000 people nationwide suffer from the condition.  90% of patients have not been diagnosed and are not receiving proper medical care for their illness (Jason LA, Richman JA, Rademaker AW, Jordan KM, Plioplys AV, Taylor RR, McCready W, Huang CF, Plioplys S: A Community-Based Study of Chronic Fatigue Syndrome Arch Int Med 1999; 159(18):2129-37.).  Few studies of CFS in children and adolescents have been published.  It is well-accepted that adolescents get CFIDS, although less frequently than adults.

WHO GETS CFIDS?

CFIDS strikes people of all age, ethnic and socioeconomic groups.  Research has shown that CFIDS is about three times as common in women (522/100,000) as men, a rate similar to that of many autoimmune diseases, such as multiple sclerosis and lupus.  To put this into perspective, CFIDS is over four times more common than HIV infection in women (125/100,000), and the rate of CFIDS in women is considerably higher than a woman's lifetime risk of getting lung cancer (63/100,000).

DO PWCS GET BETTER OVER TIME?

The course of this illness varies greatly.  Some people recover, some cycle between periods of relatively good health and illness and some gradually worsen over time.  Others neither get worse nor better while some improve gradually but never fully recover.  The CDC is conducting a long-term study of PWCs to learn more about the course of illness.  CDC investigators have reported that the greatest chance of recovery appears to be within the first five years of illness, although individuals may recover at any stage of illness. Investigators also have found an apparent difference in recovery rates based upon the type of onset.  PWCs with sudden onset reported recovery nearly twice as often as those with gradual onset.  This study is ongoing and observations about the course of illness are likely to change as more data are collected.

WHAT CAUSES CFIDS?

The cause of CFIDS is not yet known, but a growing number of researchers is dedicated to uncovering the cause/s (etiology), mechanism of disease (pathophysiology) and effect on the body(pathogenesis).  Current research shows evidence of immune system dysfunction in CFIDS.  The exact nature of this dysfunction is not yet well-defined, but is generally viewed as an up-regulated, or overactive, state.  Considerable evidence indicates that CFIDS patients have a dysfunction of the central nervous system.  Researchers are trying to identify the agent(s) responsible for causing CFIDS.  Scientist are also studying immunologic, neurologic, autonomic, endocrine and metabolic abnormalities and risk factors (such as genetic predisposition, age, sex, prior illness, environment and stress) that may affect the development and course of the illness.

ARE VIRUSES INVOLVED IN CFIDS?

Many scientists are convinced that viruses are associated with CFIDS and may cause the disease.  It was once thought that Epstein-Barr virus (EBV), a herpesvirus that causes mononucleosis, caused this syndrome.  Elevated antibodies to a number of viruses, including EBV, cytomegalovirus (CMV) and human herpesvirus-6 (HHV-6), indicate a viral component to CFIDS, although not necessarily a cause.  Enteroviruses, newly discovered retroviruses, herpesviruses and other viruses are being studied to see if they cause or contribute to the disease process.

IS CFIDS CONTAGIOUS?

No one knows what causes CFIDS or if it can be transmitted.  Most people in close contact with CFIDS patients have not developed the illness; however, clusters of cases have occurred in families, workplaces, schools and communities.  Several of these clusters have been investigated and no infectious agent has been found.  While there is no documented evidence that CFIDS is infectious, it is studied by the infectious disease divisions of the National Institutes of Health and Centers for Disease Control and Prevention.  Preliminary research indicates that genetics may help determine who gets the illness.  When members of the same family become ill, they are more often blood relatives than spouses.

WHAT PRECAUTIONS SHOULD PWCS TAKE?

PWCs should consult their physicians about what precautions may be advisable since questions remain about the possibility of contagion.  In general, persons with serious illnesses are advised against donating blood, blood products or organs.  Additionally, some physicians encourage PWCs to take universal precautions recommended to persons with infectious illnesses, particularly in the early acute stages, until more is known about CFIDS.  These measures also would help protect PWCs from common viruses and bacteria that could contribute to an increased number and/or severity of symptoms.  Most physicians believe that there is no risk to non-ill contacts and that no special precautions are necessary.

SHOULD PWCS RECEIVE FLU SHOTS OR OTHER IMMUNIZATIONS?

Persons with CFIDS often have up-regulated immune systems and frequently don't make antibodies after receiving immunizations.  Persons with up-regulated immune systems are at higher risk for adverse reactions to vaccines.  Allergy shots, however, seem to be better tolerated. PWCs are urged to consult their physicians and to analyze the potential benefits and risks before taking or refusing any immunization.

IS EXERCISE HELPFUL OR HARMFUL?

One hallmark of CFIDS is an intolerance of previously well tolerated levels of physical activity. Most PWCs' symptoms worsen severely, sometimes for days, following even minor exertion.  Physicians generally recommend that PWCs perform limited (and preferably anaerobic, e.g., light weight training) physical activity to guard against the negative consequences of deconditioning, but that they listen to their bodies and not push beyond their limits.

IS WEIGHT GAIN COMMON?

Some patients lose weight during the initial stage of the illness, but many PWCs gain it without a significant change in eating habits.  This gain may be due to CFIDS-related disturbances in metabolism as well as decreased activity.

IS DEPRESSION COMMON?

Some PWCs can develop a secondary depression as a result of--rather than a cause of--CFIDS.  Some depression is found in all chronic illnesses; it results from numerous losses, life changes and altered brain chemistry.  In some cases depression becomes very severe.  CFIDS-related depression can be managed with medication and/or supportive counseling.

WHAT ROLE DOES STRESS PLAY IN THIS ILLNESS?

Stress is very harmful to PWCs.  Physical and/or emotional stress usually worsen symptoms and contribute to relapse.  PWCs are advised to decrease the stress in their lives as much as possible.  In more global terms, stress has been found to weaken the immune system and increase susceptibility to illness in most animals, including humans.  Some researchers believe that stress (especially major life changes) may contribute to the onset of CFIDS, as it does in many other diseases.

HOW DOES PREGNANCY AFFECT CFIDS?

This issue has been explored only informally.  According to limited clinical observations, some pregnant women with CFIDS experience no change in their symptoms.  Others report symptom remission from early in the pregnancy and lasting until about six weeks after the delivery.  Pregnant women with CFIDS should seek care from an obstetrician early and often during pregnancy.  Many medications that treat CFIDS symptoms must be stopped or decreased during pregnancy and resumed after giving birth and discontinuing breast feeding.  The question of whether CFIDS can be transmitted from parent to child remains unanswered.  There is currently no evidence that babies born to parents with CFIDS are different from other babies.  When deciding whether or not to have a child, PWCs and their partners should consider the enormous expenditure of energy required to care for a baby and, later, an active child.

IS CFIDS RELATED TO OTHER ILLNESSES?

There are a host of illnesses that share many of the symptoms of CFIDS.  Fibromyalgia, neurally mediated hypotension (NMH), chronic Lyme disease and interstitial cystitis are just a few of many overlapping syndromes.  Research is underway to determine the relationship among these illnesses.  Specifically, fibromyalgia means pain in the muscles, ligaments and tendons.  The requisite for diagnosis of fibromyalgia is widespread pain lasting a minimum of three months and at least 11 of 18 specified tender points clustering around the neck, shoulders, chest, hips, knees and elbows.  Other symptoms commonly experienced by persons with fibromyalgia include sleep disturbance, cognitive difficulties, irritable bowel, fatigue and headache.

 Researchers at Johns Hopkins University have reported preliminary evidence supporting a link between CFIDS and a known blood pressure disorder called neurally mediated hypotension (NMH) or vasodepressor syncope.  In NMH, the brain and the heart do not communicate properly, even though both are structurally normal.  An inappropriate response to adrenaline (a hormone produced when the body is under stress) causes blood pressure to fall when it should rise.  Individuals with NMH feel lightheaded and may feel faint when this condition is triggered by various physical and emotional stressors.  Cognitive problems, muscle aches and severe fatigue often follow and can become chronic.  Further studies, including clinical trials of treatments used to manage this condition, are underway at Beth Israel Deaconess Hospital, Johns Hopkins University, the National Institutes of Health and other medical centers.

FOR MORE INFORMATION:

MASSACHUSETTS CFIDS ASSOCIATION

P.O. Box 690305, Quincy, MA 02269-0305

617-471-5559 (Volunteer Information Line)

Website: www.masscfids.org,

Email: masscfids@masscfids.org

CFIDS ASSOCIATION OF AMERICA

PO Box 220398, Charlotte, NC 28222-0398

Info Line: 800/442-3437

Website: www.cfids.org