October 23, 2000
NIMH study links
childhood abuse,
adult stress
By Lillian Kim
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 Emorys
Conte Center for the Neuroscience of Mental Disorders, funded by the National
Institute of Mental Health (NIMH) and led by Charles Nemeroff. The studys findings, which appeared recently in 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 disorder. 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 Nemeroff and his colleagues. Nemeroff is chair
and Reunette W. Harris Professor of Psychiatry and Behavioral Sciences
in the School of Medicine and the studys principal investigator.
The studys lead author is Christine Heim, currently of the University
of Trier in Germany. Essentially, were trying to understand the biological basis
behind the risk for developing psychiatric disorders in adulthood,
Nemeroff explained. In the study, 49 adult female subjects, between 18
and 45, were divided into four groups: Those who were abused as children
and 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, Nemeroff
said. All subjects underwent the Trier social stress testnamed after
the university where it was developedwhich involves 10 minutes of
public speaking and a tricky mental math exercise, performed before a
panel of poker-faced observers who purposely do not evince any supportive
expressions or gestures. During the test, the subjects stress hormonal responses were measured
using 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 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 as children
and who had current major depression, while women who were depressed but
had not experienced child abuse showed hormonal responses similar to those
in the control group. Previous research 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 some of the measured hormonal
responses. Researchers hope to learn 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 could
have prophylactic benefit, Dr. Nemeroff said. Other Emory researchers involved in the study are Jeffrey Newport, Stacey Heit, Yolanda Graham, Molly Wilcox, Robert Bonsall and Andrew Miller. |