Family Medical History of Persons with Chronic Fatigue Syndrome

Article (PDF Available)inJournal of Chronic Fatigue Syndrome 12(4) · January 2011with 94 Reads
DOI: 10.1300/J092v12n04_03
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Background: Little research has examined the family his-tory of persons with CFS, although a few studies have found people with CFS may be more likely to have family members with fatigue or CFS-like conditions, cancers, autoimmune illness, and early parental death. Research into the family history of fatigue, chronic fatigue syn-drome, and other medical or psychiatric illness may help inform the eti-ology of this illness. Objectives: The present investigation examined the occurrence of medical and psychiatric illness in the family history of persons with CFS, and then compared these results with the family history of medical illness reported by a control group of persons without fatigue. Methods: Family medical history data was obtained from question-naire responses, a medical assessment, and medical records, and were then classified into specific illness categories, using the International Classification of Diseases, Tenth Revision (ICD-10). Family history data was compared among three groups using logistic regression analyses.
Family Medical History of Persons
with Chronic Fatigue Syndrome
Susan R. Torres-Harding, PhD
Leonard A. Jason, PhD
O. Dicle Turkoglu, BA
ABSTRACT. Background: Little research has examined the family his-
tory of persons with CFS, although a few studies have found people with
CFS may be more likely to have family members with fatigue or
CFS-like conditions, cancers, autoimmune illness, and early parental
death. Research into the family history of fatigue, chronic fatigue syn-
drome, and other medical or psychiatric illness may help inform the eti-
ology of this illness.
Objectives: The present investigation examined the occurrence of
medical and psychiatric illness in the family history of persons with
CFS, and then compared these results with the family history of medical
illness reported by a control group of persons without fatigue.
Methods: Family medical history data was obtained from question-
naire responses, a medical assessment, and medical records, and were
then classified into specific illness categories, using the International
Classification of Diseases, Tenth Revision (ICD-10). Family history data
was compared among three groups using logistic regression analyses.
Susan R. Torres-Harding and Leonard A. Jason (E-mail: are
affiliated with the Center for Community Research, 990 West Fullerton, Room 3100,
Chicago, IL 60614.
O. Dicle Turkoglu is affiliated with the University of Vermont, Department of Psy
chology, John Dewey Hall Room 246, 2 Colchester Avenue, Burlington, VT 05405-
0134 (E-mail:
Address correspondence to: Susan R. Torres-Harding, PhD, Center for Community
Research, 990 West Fullerton, Room 3100, Chicago, IL 60614 (E-mail: storres@
NIAID grant number AI36295 provided financial support for this study.
Journal of Chronic Fatigue Syndrome, Vol. 12(4) 2004
Available online at
2004 by The Haworth Press, Inc. All rights reserved.
doi:10.1300/J092v12n04_03 25
Results: Results indicated that persons with chronic fatigue syndrome
were significantly more likely to report a family history of endocrine/
metabolic disorders when compared to the control group.
Conclusions: Findings suggest an underlying familial predisposition
toward the development of both CFS and endocrine/metabolic disorders.
This finding is consistent with the hypothesis that CFS represents a dereg
ulation of the endocrine system.
[Article copies available for a fee from The
Haworth Document Delivery Service: 1-800-HAWORTH. E-mail address:
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2004 by The Haworth Press, Inc. All rights reserved.]
KEYWORDS. Chronic fatigue syndrome, family medical history, en
docrine, metabolic
Research to date on chronic fatigue syndrome (CFS) has implicated
pathophysiological findings in immunological, endocrinological, and
neurological systems that may serve as causal or perpetuating factors in
this illness (1). Several researchers have suggested that the symptoms of
CFS are consistent with chronic low-level activation of the immune sys-
tem (2,3). Immunological abnormalities that have been reported in per-
sons with CFS include elevation of activated T lymphocytes, elevations
of circulating cytokines, low natural killer cell cytotoxicity, poor lym-
phocyte response to mitogens in culture, and deficiencies in IgG1 and
IgG3 (4). Neurological and neurocognitive abnormalities reported in-
clude abnormal white matter on MRI (5) and impairments in complex
information processing speed and efficiency (6). Neuroendocrine abnor
malities, such as insufficient glucocorticoid functioning or atrophy of the
adrenal glands, with resulting hypocortisolism, have led some research-
ers to propose that CFS is caused by underactivity or deregulation of the
hypothalamic-pituitary-adrenal axis (7,8). Finally, some researchers
have suggested that CFS may involve a chronic activation of the sympa
thetic nervous system (9). Autonomic system abnormalities that have
been associated with CFS include delayed orthostatic intolerance, neu
rally mediated hypotension (10), and lowered blood volume (11).
However, these findings have not been consistently reported across
studies. The relationship between these possible abnormalities and their
role in causing or maintaining this illness remains unclear. Further, these
abnormalities may be the result, rather than the cause, of another, as yet
undiscovered, disease process.
The comorbidity of psychiatric illness with CFS has consistently been
demonstrated to be higher in people with CFS when compared to other
chronically ill medical patients or healthy (12-16), although the types of
instruments used to diagnose psychiatric disorder may affect the rates of
psychiatric comorbidity (14). Because of high psychiatric comorbidity,
some researchers have proposed that CFS is a variant of depressive disor
der. However, research has generally supported the idea that depressive
disorder and chronic fatigue syndrome are distinct syndromes (7).
Examining the family history of illness may help provide insight to
possible etiology for this illness. If a higher rate of family illness exists,
this may indicate a genetic predisposition or underlying vulnerability to
developing a CFS-like illness. Alternately, environmental influences
may explain this link through shared experiences, such as exposure to
toxins or viruses, or through a negative emotional/psychological milieu.
Finally, it is possible that both genetic and environmental factors interact
to cause CFS and other fatigue-like illnesses. For example, when com-
paring sample of 30 patients with CFS with 30 fracture clinic outpatients,
Fisher and Chalder (17) found that a history of maternal depression and
overprotection were more common in patients with CFS. Hickie et al.
(18) found evidence that an interaction of genetic and environmental fac-
tors may influence the development of fatigue. In their community-based
study of 124 monozygotic and dizygotic twin pairs, a single common ge-
netic factor predicted psychological distress, fatigue, and enhanced im-
mune responsiveness. They also found an environmental factor that
predicted both fatigue and decreased immune response. It is possible that
both genetic and environmental factors interact in a complex manner to
determine whether people develop CFS or similar fatigue-related ill-
nesses, psychological distress, and/or poorer immune system function-
Endicott (19) examined the occurrence of medical illness in family
histories of persons with chronic fatigue syndrome. In this study, the
medical and psychiatric family history of 45 psychiatric patients with
comorbid chronic fatigue syndrome were compared to the family history
of 90 healthy psychiatric patients and 45 psychiatric patients randomly
chosen without regard to health status. His results indicate that patients
with CFS had mothers that died at a younger age than the group of ran
domly chosen psychiatric patients; both parents died before the age of 65
more frequently for the CFS patients than for the group of healthy con
trols; and the parents of patients with CFS had an increased prevalence of
cancer, autoimmune disorders, and CFS-like conditions. Further, Endi
cott reported no difference in the family history of psychiatric disorders
Original Research 27
as compared to the two control groups. This study represented an impor
tant step in assessing the possible familial contributions to the develop
ment of chronic fatigue syndrome. However, it was limited in scope
because all of the study participants were psychiatric patients, and the
results obtained may not generalize to persons with CFS without a
comorbid psychiatric disorder.
Finally, Walsh et al. (20) examined the family history of 25 persons
with CFS and compared results to a group of 36 age- and sex-matched
control subjects with either inflammatory bowel disease, Crohn’s dis
ease or ulcerative colitis. In this investigation, the researchers found that
persons with CFS had a higher occurrence of familial chronic fatigue and
CFS when compared to the controls. There were no significant differ-
ences between the two groups on the occurrence of psychiatric disorder
in family members.
The present study investigated the occurrence of medical and psychi-
atric disorders in the family history of persons with CFS drawn from a
community-based sample. It is expected that family history of cancer, fa-
tigue or chronic fatigue will be higher in the CFS group when compared
to controls, as a positive family history for these illnesses has been re-
ported for persons with CFS (19,20). Because there is evidence that per-
sons with CFS may experience abnormalities in the nervous, immune,
and endocrine systems, it is hypothesized that persons with CFS have a
higher incidence of neurological disorders, endocrinological, and immu-
nological illnesses in their family medical history, when compared to a
control group of persons without chronic fatigue. Finally, the relative
rates of psychiatric disorders were examined between the two groups, to
determine whether persons with CFS report more familial psychiatric
illness when compared to the control group.
The data are derived from a larger community-based study of the prev
alence of chronic fatigue syndrome (21). This larger study was carried
out in three stages. Stage 1 involved administering an initial telephone
screening questionnaire in order to identify the symptoms of chronic fa
tigue syndrome. Stage 2 involved administering a semi-structured psy
chiatric interview. In Stage 3, participants underwent a complete physical
examination. Following the completion of the medical evaluation, four
physicians and a psychiatrist were responsible for making a final diagno
sis with two physicians independently rating each case using the current
US case definition of CFS (22). Where disagreement occurred, a third
physician rater was used.
Procedures developed by Kish (23) were used to select one adult from
each household. Birth dates for each adult were gathered, and the person
with the most recent birthday was selected for interview. A stratified ran
dom sample of several neighborhoods in Chicago was utilized. In Stage
1, 28,673 residential/working telephone numbers were contacted, and
18,675 adults completed the initial screening interview (65.1% comple-
tion rate).
The Stage 1 screen revealed that of the 18,765 participants who were
interviewed, 780 (4.2%) had chronic fatigue. Of these, 408 had chronic
fatigue and the concurrent occurrence of four or more symptoms. These
participants were defined as CFS-like (the suffix “like” was used to clar-
ify that individuals in this group only met the Fukuda et al. (22) criteria by
self-report, and did not necessarily qualify as having a final diagnosis of
CFS rendered by a physician).
One hundred sixty-six of the 408 CFS-like participants agreed to com-
pletea structured psychiatricinterviewandacomprehensivephysicalex-
amination. There were no significant differences on sociodemographic
variables (i.e., gender, ethnic identification, age, occupation, education,
and marital status) or fatigue scores between these 166 screened positive
(CFS-like) participants and the 242 screened positive (CFS-like) non-
participants. The control group was composed of 199 individuals se-
lected randomly from the remaining 18,260 screened negatives (seven
cases were excluded due to missing data). Of these 199 individuals, 47
completed medical evaluations. There were no sociodemographic differ
ences (i.e., gender, ethnic identification, age, occupation, education, and
marital status) or fatigue scores between the 152 screened negative
non-participants and 47 screened negative participants. Participants
were then classified by independent physician consensus. The physician
panel classified 32 persons as having chronic fatigue syndrome, 45 with
idiopathic chronic fatigue, and 89 with fatigue caused by either a
psychiatric or medical illness. The control group consisted of 47 persons
who screened negative for CFS-like symptoms.
Original Research 29
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