Women Abused as Children Show Elevated Hormonal Responses to Stress
That May Add to risk of Adult Psychiatric Disorders
DENVER -- Women who were sexually or physically abused as children show
significantly elevated hormonal responses to stress compared to women
with no history of childhood abuse, according to a study by researchers
at the Emory University Conte Center for the Neuroscience of Mental
Disorders, which is funded by the National Institute of Mental Health
and led by Charles B. Nemeroff, M.D., Ph.D. Dr. Nemeroff presented his
findings on Feb. 14 in a symposium at the American Association for the
Advancement of Science (AAAS) annual meeting in Denver.
The study's findings, previously
reported in the August 2000 issue of the Journal of the American Medical
Association, suggest that childhood abuse is associated with persistent
sensitization or hyperactivity of the pituitary-adrenal and autonomic
stress response, which in turn may contribute to greater vulnerability
to psychiatric disorders in adulthood.
The findings support the
hypothesis that aberrant brain chemistry produced by adverse early-life
experiences plays a major role in the later development of mood and
anxiety disorders. This hypothesis, the Stress-Diathesis Model of Mood
Disorders, was put forth several years ago by Dr. Nemeroff and his colleagues.
Dr. Nemeroff is the chair of the Department of Psychiatry and Behavioral
Sciences at the Emory University School of Medicine and the study's
principal investigator. The study's lead author is Christine Heim, Ph.D.
"Essentially, we're trying
to understand the biological basis behind the risk for developing psychiatric
disorders in adulthood," Dr. Nemeroff explained.
In the study, 49 adult female
subjects, aged 18-45 years, were divided into four groups: those who
were sexually or physically abused as children and were diagnosed with
depression in adulthood; those who were abused in childhood but had
not experienced depression; depressed women who did not suffer child
abuse; and a control group with no history of childhood abuse or depression.
"We sought to distinguish
the effects of depression versus the effects of early childhood trauma
on the stress hormonal systems," said Dr. Nemeroff
All of the subjects underwent
the Trier social stress test, named after the University of Trier, where
it was developed. The test involved 10 minutes of public speaking and
a tricky mental math exercise, performed before a panel of poker-faced
observers who purposely did not evince any supportive expressions or
gestures.
During the test the subjects'
stress hormonal responses were measured via blood samples taken through
an intravenous catheter. The catheter was inserted two hours before
the stress test to avoid incurring any needle sticks during the actual
test performance.
The hormones measured were
cortisol and ACTH, or adrenocorticotropic hormone, members of the hypothalamic-pituitary-adrenal
axis, both of which are stimulated by corticotropin-releasing factor
(CRF). Increased concentrations of cortisol and ACTH are indicative
of hyperactive or sensitized CRF systems; the latter have been strongly
implicated in mediating the relationship between early-life stress and
adulthood development of depression and anxiety disorders.
The researchers found that
both groups of women who were abused as children showed exaggerated
stress hormonal responses. The effect was especially pronounced in women
who were abused s children and who had current major depression: these
subjects' ACTH responses were more than six times those of control group
members who were comparable in age.
The women who were depressed
but had not experienced child abuse showed hormonal responses similar
to those in the control group.
Previous research by others
has shown that adults who were abused as children may be at greater
risk of developing anxiety disorders, including post-traumatic stress
disorder, and depression.
In an ongoing follow-up study,
the researchers are evaluating the effectiveness of antidepressant medication
aimed at blocking the action of CRF within the brain, so-called CRF
receptor antagonists. Researchers hope to lean whether such novel drugs
could not only treat, but also prevent adult psychiatric disorders associated
with early-life stress.
"If we find that this is
the case, antidepressants potentially cold have prophylactic benefit,"
Dr. Nemeroff said.
Other Emory researchers involved
in the study are D. Jeffrey Newport, M.D., Stacey Heit, M.D., Yolanda
P. Graham, M.D., Molly Wilcox, B.A., Robert Bonsall, Ph.D. and Andrew
H. Miller, M.D.
Dr. Nemeroff, who also is
the Reunette W. Harris Professor of Psychiatry and Behavioral Sciences,
specializes in researching the biological basis of major neuropsychiatric
disorders, including mood disorders, schizophrenia and anxiety disorders.
In June 1998, he published an article in Scientific American presenting
the Stress-Diathesis hypothesis.
This hypothesis became the
basis for a five-year $13 million grant awarded in 1999 by the National
Institute of Mental Health (NIMH) of the National Institutes of Health.
The grant supported the establishment of the Emory Conte Center for
the Neuroscience of Mental Disorders, which involves a large team of
neuroscientists from Emory, Yale and Princeton, led by Dr. Nemeroff.
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