How Many Kids Have CFIDS?
By Rebecca C.
Originally published in Youth Allied By
CFIDS, Winter 1997
We want a diagnostic test, better
treatments and a cure for kids with CFIDS! For these things to happen, we need
research to answer many questions about CFIDS in kids.
Pediatric CFIDS research wonít be conducted
unless doctors, researchers and the government think that there are enough
children and teenagers with the disease to make studying it
If high-quality, respected studies find
that there are many children and teenagers with CFIDS in the U.S., it will be
easier to interest researchers in studying pediatric CFIDS, agencies in funding
pediatric CFIDS research, and doctors in learning about it.
Studies that determine how many cases of a
disease are present in a group of people are called prevalence studies. If a
disease is very prevalent, that means it is very common.
When researchers want to know how prevalent
a disease is, they study a specific number of people (i.e., people randomly
chosen from the phone book) and find out how many of them have the disease. The
number of people with the disease, compared to the total number of people
studied, is the prevalence rate.
Scientists usually express prevalence rates
in terms of the number of persons with a disease likely to be found in a group
of 100,000 randomly chosen people. They do this so that the prevalence rates
from different studies, involving populations of varying sizes, can be compared.
(Itís kind of like when you choose a common denominator in order to be able to
compare different fractions.)
How Did the CDC Study
The CDCís data about how
common CFIDS is in kids is included in the table below. To help you
understand why the results of the three studies are so different, here are brief
descriptions of what the CDC did in each one:
- Physician-referral study:
Between 1991 and 1993 the four-city physician referral study (in which
more than 900 doctors agreed to tell the CDC about any cases of CFIDS that
they diagnosed) was expanded to include patients 12 years and older.
Physicians participating in the study were notified that adolescent cases
meeting the stringent 1988 CDC case definition for CFS should be reported to
- School Nurses Study:
In 1993, all 36 nurses from the middle, junior high and senior high
schools in Wichita, KS and Reno, NV assisted the CDC in studying chronic
fatigue in adolescents. Those who reported they had been diagnosed with CFS by
a physician were counted towards the CFS prevalence rate for this study. The
nurses reported that 22 adolescents had severe fatigue and that 10 of them had
been diagnosed with CFS.
- San Francisco Study: In
1994, the CDC phoned randomly chosen households in San Francisco, in hopes of
identifying all household residents ages two and up who had chronic fatigue.
Those who met the CDCís 1994 case definition were said to have CFS-like
illness. There was no physician evaluation of patients.
The first two studies have been criticized
because the only kids counted were the ones who had doctors who recognized and
diagnosed their CFIDS and then notified the CDC and/or the school nurses, who
then told the CDC. The third study has been criticized because no medical
work-ups were done, so there is no way to know whether the patients identified
truly had CFIDS or something entirely different.
For these reasons, CYA and The CFIDS
Association of America are lobbying the government to conduct more studies that
will more accurately identify the number of kids who have CFIDS.
Weíre only beginning to learn about
the ways that the CDC has studied pediatric CFIDS. CYA volunteers will continue
to study this issue so that we can update you in future editions of YABC.
CDC Announces Prevalence Rates for CFIDS in Young
Dr. Jim Dobbins of
the Centers for Disease Control presented prevalence rates for CFIDS in children
and adolescents at the American Association for Chronic Fatigue Syndrome (CFIDS)
in October 1996. The rates were calculated from data collected in past CDC
studies. These studies and Dr. Dobbinsí conclusions are discussed in the article
above. For more information on the results of the three studies and why they are
different, see the article above.
*"CFS-like illness" is used because the
diagnosis was made by a team reviewing medical records for symptoms and illness
history (physician-referral study) or based on responses to a telephone survey
(San Francisco study), rather than by a physician examining the
CDC estimates that 20% of "CFS-like" cases
would meet the full criteria for CFS if a full medical work-up and lab tests
The prevalence rate given by CDC for
CFS-like illness in adults is "between 76 and 233 per 100,000."