Dissociation between pituitary and adrenal suppression to dexamethasone in depression.
OBJECTIVE
To determine if corticotroph nonsuppression, as reflected by beta-endorphin nonsuppression, occurs before cortisol nonsuppression (defined as a cortisol level of > 140 nmol/L) when examining multiple time points in a day.


METHODS
The General Medical Clinical Research Center and Inpatient Depression Research Unit, Ann Arbor, Mich.


METHODS
Multiple blood samples were obtained through an intravenous catheter around the time points of 8 AM, noon, and 4 PM and assayed for beta-endorphin and cortisol.


METHODS
Patients meeting Research Diagnostic Criteria for the diagnosis of major depressive disorder, primary and simple. A total of 73 subjects, both inpatients and outpatients, were studied.


METHODS
Samples were obtained both at baseline and 1 day after administration of 1 mg of dexamethasone at 11:30 PM.


RESULTS
Overall 39 patients (53%) demonstrated beta-endorphin nonsuppression after administration of dexamethasone at any of the three time points, while only eight patients (11%) demonstrated cortisol nonsuppression at any of these time points. Cortisol nonsuppression, but not beta-endorphin nonsuppression, was associated with lower concentrations of dexamethasone in plasma. Baseline cortisol and menopausal status were significantly associated with beta-endorphin nonsuppression in women.
Young
E A
EA
Department of Psychiatry, University of Michigan Medical Center, Ann Arbor.
Kotun
J
J
Haskett
R F
RF
Grunhaus
L
L
Greden
J F
JF
Watson
S J
SJ
Akil
H
H
D000328:Adult; D000367:Age Factors; D000553:Ambulatory Care; D002940:Circadian Rhythm; D003866:Depressive Disorder / Q000097:blood / Q000175:diagnosis* / Q000523:psychology; D003907:Dexamethasone / Q000097:blood; D005260:Female; D006760:Hospitalization; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D008593:Menopause; D008875:Middle Aged; D012008:Recurrence; D012737:Sex Factors; D001615:beta-Endorphin / Q000097:blood*
D001615:beta-Endorphin; D003907:Dexamethasone; D006854:Hydrocortisone