Chronic fatigue syndrome, or CFS,
is a debilitating and complex disorder characterized by profound fatigue that is
not improved by bed rest and that may be worsened by physical or mental
activity. Persons with CFS most often function at a substantially lower level of
activity than they were capable of before the onset of illness. In addition to
these key defining characteristics, patients report various nonspecific
symptoms, including weakness, muscle pain, impaired memory and/or mental
concentration, insomnia, and post-exertional fatigue lasting more than 24 hours.
I
n some cases, CFS can persist for
years. The cause or causes of CFS have not been identified and no specific
diagnostic tests are available. Moreover, since many illnesses have
incapacitating fatigue as a symptom, care must be taken to exclude other known
and often treatable conditions before a diagnosis of CFS is made.
in order to receive a diagnosis of
chronic fatigue syndrome, a patient must satisfy two criteria:
-
Have severe chronic fatigue of
six months or longer duration with other known medical conditions excluded by
clinical diagnosis; and
-
Concurrently have 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 swelling or redness; headaches of a new type, pattern or severity;
unrefreshing sleep; and post-exertional malaise lasting more than 24 hours.
The symptoms must have persisted or
recurred during six or more consecutive months of illness and must not have
predated the fatigue.
In addition to the eight primary
defining symptoms of CFS, a number of other symptoms have been reported by some
CFS patients. The frequencies of occurrence of these symptoms vary from 20% to
50% among CFS patients. They include abdominal pain, alcohol intolerance,
bloating, chest pain, chronic cough, diarrhea, dizziness, dry eyes or mouth,
earaches, irregular heartbeat, jaw pain, morning stiffness, nausea, night
sweats, psychological problems (depression, irritability, anxiety, panic
attacks), shortness of breath, skin sensations, tingling sensations, and weight
loss.
Prevalence of CFS
Chronic fatigue syndrome (CFS)
affects more than one million people in the United States. There are tens of
millions of people with similar fatiguing illnesses who do not fully meet the
strict research definition of CFS.
Risk Factors for CFS
-
People of every age, gender,
ethnicity and socioeconomic group can have CFS.
-
CFS affects women at four times
the rate of men.
-
Research indicates that CFS is
most common in people in their 40s and 50s.
-
Although CFS is much less common
in children than in adults, children can develop the illness, particularly
during the teen years.
-
In addition to fatigue, CFS
includes eight characteristic symptoms:
-
postexertional malaise (relapse
of symptoms after physical or mental exertion);
-
unrefreshing sleep;
-
substantial impairment in
memory/concentration;
-
muscle pain;
-
pain in multiple joints;
-
headaches of a new type,
pattern or severity;
-
sore throat; and
-
tender neck or armpit lymph
nodes.
Treatment
Since there is no known cure for
CFS, treatment is aimed at symptom relief and improved function. A combination
of drug and nondrug therapies is usually recommended. No single therapy exists
that helps all CFS patients.
Lifestyle changes, including
prevention of overexertion, reduced stress, dietary restrictions, gentle
stretching and nutritional supplementation, are frequently recommended in
addition to drug therapies used to treat sleep, pain and other specific
symptoms.
Carefully supervised physical
therapy may also be part of treatment for CFS. However, symptoms can be
exacerbated by overly ambitious physical activity. A very moderate approach to
exercise and activity management is recommended to avoid overactivity and to
prevent deconditioning.
Recovery from CFS
CFS affects each individual
differently. Some people with CFS remain homebound and others improve to the
point that they can resume work and other activities, even though they continue
to experience symptoms.
Recovery rates for CFS are unclear.
Improvement rates varied from 8% to 63% in a 2005 review of published studies,
with a median of 40% of patients improving during follow-up. However, full
recovery from CFS may be rare, with an average of only 5% to 10% sustaining
total remission.
