Sex differences in hormonal responses to a social stressor in chronic major depression.
BACKGROUND
Acute depression has been associated with increased hypothalamic-pituitary-adrenal (HPA) reactivity. While chronicity of depressive illness influences symptoms, course and outcome, its effect on the HPA axis has not been extensively evaluated. The current study evaluated cortisol stress responses to a social challenge in chronic major depressive disorder (CMDD).


METHODS
Cortisol stress responses to the Trier Social Stress Test (TSST) were compared in 26 participants with CMDD and 28 healthy controls using repeated measures analysis of variance (RANOVA). In addition, group differences in area under the curve (AUC) and peak percentage change in cortisol were examined.


RESULTS
The RANOVA indicated a significant sex by condition interaction in cortisol responses to the social challenge. Post-hoc testing of pair-wise group differences revealed that in females, CMDD subjects had greater cortisol levels in response to the TSST than did controls. Similarly, AUC was greater in females with CMDD than in female controls. Neither of these differences was significant in males. However, male CMDD subjects exhibited a significantly decreased peak percentage change in cortisol in response to the TSST than did male controls.


CONCLUSIONS
Males and females with CMDD exhibited unique differences in cortisol responses to the social challenge relative to controls. In females, CMDD subjects had greater overall secretion of cortisol whereas in males, CMDD subjects had a blunted peak response to the social stressor. Sex differences are an important consideration in future work in this population.
Chopra
Kevin K
KK
Centre for Addiction and Mental Health, Toronto, Ontario, Canada. kevin_chopra@camh.net
Ravindran
Arun
A
Kennedy
Sidney H
SH
Mackenzie
Bronwyn
B
Matthews
Stephen
S
Anisman
Hymie
H
Bagby
R Michael
RM
Farvolden
Peter
P
Levitan
Robert D
RD
D000328:Adult; D016022:Case-Control Studies; D002908:Chronic Disease / Q000523:psychology; D003865:Major Depressive Disorder / Q000378:metabolism* / Q000523:psychology*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D012463:Saliva / Q000378:metabolism; D012727:Sex Characteristics; D013315:Stress, Psychological / Q000378:metabolism*; D013997:Time Factors
D006854:Hydrocortisone