Association between response to lithium augmentation and the combined DEX/CRH test in major depressive disorder.
Although lithium augmentation is the foremost and most well-documented treatment strategy for treatment resistant depression, knowledge of factors related to response remains scanty. Findings with the combined dexamethasone/corticotropin-releasing hormone (DEX/CRH) test are associated with response to treatment with a tricyclic antidepressant. This study investigated the potential predictive value of the DEX/CRH test for lithium augmentation response in major depressive disorder. The DEX/CRH test was conducted prior to lithium augmentation in 30 patients with a major depressive episode who had not responded to an antidepressant monotherapy trial of at least 4 weeks. Response status was assessed weekly using the Hamilton Rating Scale for Depression. For multivariate prediction, a logistic regression analysis was performed. Eleven (37%) patients responded to lithium augmentation within 4 weeks. Responders showed higher ACTH response and lower cortisol response in the DEX/CRH test, but results were not statistically significant. However, non-responders had a statistically significant higher cortisol/ACTH peak ratio (3.43+/-1.75) compared to responders (2.18+/-1.38) (P=0.027). This ratio is an indicator for the sensitivity of the adrenal cortex to ACTH. A cortisol/ACTH peak ratio of 1.8 was identified as the best cutoff point to differentiate responders from non-responders. In conclusion, results suggest a more sensitive adrenal cortex in non-responders to lithium augmentation. The findings would be in line with the assumption of a more chronic course of depression with more pronounced biological alterations in the non-responder group, because chronic depression is known to cause enlargement of the adrenal gland with a subsequent hypersensitivity to ACTH. Results of this study should be confirmed in a larger study group.
Bschor
Tom
T
Department of Psychiatry, Technische Universität Dresden, Fetscherstrasse 74, D-01307, Dresden, Germany. bschor@mailbox.tu-dresden.de
Baethge
Christopher
C
Adli
Mazda
M
Eichmann
Uta
U
Ising
Marcus
M
Uhr
Manfred
M
Modell
Sieglinde
S
Künzel
Heike
H
Müller-Oerlinghausen
Bruno
B
Bauer
Michael
M
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000928:Antidepressive Agents / Q000627:therapeutic use*; D003346:Corticotropin-Releasing Hormone; D003865:Major Depressive Disorder / Q000097:blood / Q000188:drug therapy*; D003907:Dexamethasone; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008094:Lithium / Q000627:therapeutic use*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D016896:Treatment Outcome
D000928:Antidepressive Agents; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D008094:Lithium; D006854:Hydrocortisone