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The latest information on research,
treatment and diagnosis of CFIDS and
A shorter duration
of illness seems to predict a better outcome for people with CFIDS, according to
a recent study from the Netherlands led by Sieberen P. van der Werf.
One year after the
study began, eight percent of subjects who had CFIDS or idiopathic chronic
fatigue for less than 24 months reported that they were recovered, and 38
percent reported that their symptoms had improved. By contrast, a prior study of
people who were ill for an average of 8.8 years found that only three percent
reported they had recovered and 17 percent reported they had improved.
In the present study, published in
the Journal of Psychosomatic
all of the recovered patients had been ill for less than 15 months. Other
predictors of improvement were: fewer reported concentration problems at onset,
acceptance that biological, psychological and social factors all may be involved
in the illness, and better satisfaction with social support systems.
A limitation of this
study is that improvement was assessed at a single point in time. Because CFIDS
is known to be a relapsing-remitting illness, the authors suggest that future
studies assess the patients’ abilities to maintain improvement over
proposed for CFIDS cases
researcher uses the 1994 case definition of chronic fatigue syndrome (CFS) to
select patients for a study, there is no guarantee that his test subjects will
have the same symptoms — or even the same illness — as those of another
researcher who is using the same case definition. Researchers have different
ways of interpreting ambiguous symptom criteria (e.g., fatigue which
“substantially” reduces activity), defining comorbid and exclusionary conditions
(e.g, fibromyalgia) and selecting subjects based on particular features of
interest (e.g., presence of HHV-6 antibodies). These problems with the case
definition lead to an overly broad, diverse population who meet the CFS
criteria, but may have different illness features.
For this reason,
classifying research subjects into subsets of people with similar symptoms or
illness history has been recommended as a way to more carefully describe and
compare research subjects from one study to another. It has also been proposed
that studying narrower subgroups may help researchers detect differences among
the groups in terms of treatment and outcome. This could result in improved
treatment for some portion of the larger CFIDS group.
scheme, proposed by Eng M. Tan and colleagues, aims to address some of these
problems. The researchers proposefour categories: A) nervous system involvement
(impaired memory or concentration, headache); B) endocrine system involvement
(unrefreshing sleep, postexertional malaise); C) musculoskeletal system
involvement (muscle pain, joint pain); and D) immune system/infection
involvement (sore throat, tender cervical or axillary lymph nodes).
Patients would be
identified by letters, based upon the organ systems involved in their particular
case. For example, someone with a history of headache, unrefreshing sleep and
memory problems would be classified as CFS-AB, while another person with
predominant muscle pain and sore throat would be classified as
Although this particular subclassification
scheme has not been tested
validated, the researchers hope that it will spur new ways of thinking about
CFIDS and additional ways to develop more homogenous study groups. The scheme
was published in the Journal of Clinical Immunology.
risk of CFIDS
Ten years after
outbreak of Q fever in England, most of those infected continue to experience
symptoms of CFIDS and profound fatigue. Compared to a matched group of control
subjects, patients exposed to Q fever were nearly twice as likely to have
profound fatigue (66.7% vs. 34.7%), 2.5 times more likely to have idiopathic
chronic fatigue (34.7% vs. 13.9%) and nearly five times more likely to have
CFIDS (19.4% vs. 4.2%).
Q fever is caused by an organism called
be spread from infected farm animals to humans. In its acute phase, the illness
causes headache, fatigue, sweating and other symptoms. The U.K. researchers who
conducted this study continue to explore reasons for the increased incidence of
CFIDS and profound fatigue among survivors of the 1989 Q fever outbreak, which
occurred in the West Midlands portion of the country. This study, published in
Quarterly Journal of Medicine, furthers the
literature on the role of infections in precipitating CFS. The lead author in
the study is M.J. Wildman.
CDC site offers
The Web site
of the U.S. Centers for Disease Control and Prevention (CDC)
offers an overview of its program for CFIDS research program. The site also
features general information on CFIDS and treatments, plus a list of research
papers relating to the illness. All the information on the site is in the public
domain, meaning it can be reproduced and distributed. The site’s address is:
CFIDS Glossary: Terms you need to
Reading research studies can be daunting
task for a lay audience.
with this issue, the Chronicle will try to simplify things by defining
key research terms in a CFIDS Glossary. If you have suggestions for terms to
include in future editions of the glossary, please send them to
firstname.lastname@example.org, or to The CFIDS Association of America, PO Box
220398, Charlotte, NC 28222-0398, Attention: Chronicle glossary.
Pain in a joint. In the 1994 case
definition of CFIDS, arthralgia is included in the list of symptoms, provided
that the joint pain is not accompanied by swelling or redness.
study: A type of study in which neither
the test subject nor the researcher knows what treatment, if any, the subject is
For example: In a test
to determine whether a drug has an effect against CFIDS symptoms, some subjects
will receive doses of the drug while others will receive fake, or placebo,
doses. The researcher and subjects are unaware of who is receiving the drug
until after the study is completed. This is designed to eliminate any bias,
intentional or unintentional, that a researcher or test subject may have about
A body system consisting of a series
of glands that produce hormones to control internal organ functions. The
endocrine system includes the hypothalamus, pituitary gland, thyroid,
parathyroids, adrenal glands, pineal gland and pancreas. Researchers speculate
that malfunctions in the endocrine system may be related to some cases of CFIDS.
Of, or relating to, a condition that has
known cause. Idiopathic fatigue, for instance, is fatigue that has no known
Ribonuclease L. This protein is part of the
body’s defense system against viral infections. Researchers have discovered that
some people with CFIDS have an unusual variation of this protein, one which is
smaller and more active than normal. What role this version of RNAse L (called
37 kDa RNase L) plays in CFIDS remains uncertain.