Differences in the response to the combined DEX-CRH test between PTSD patients with and without co-morbid depressive disorder.
BACKGROUND
Neuroendocrine studies have shown profound alterations in HPA-axis regulation in posttraumatic stress disorder (PTSD). Based on baseline assessments and the response to dexamethasone, a hypothalamic overdrive with enhanced glucocorticoid feedback inhibition has been suggested. The dexamethasone-corticotrophin releasing hormone (DEX-CRH) test has shown to be a more sensitive test to assess HPA-axis dysregulation in major depression and therefore may provide a useful test tool to probe HPA-axis regulation in PTSD.


METHODS
To evaluate the effect of PTSD on HPA-axis regulation, we compared the response to a DEX-CRH test between male veterans with PTSD (n=26) and male veterans, who had been exposed to similar traumatic events during their deployment, without PTSD (n=23). Patients and controls were matched on age, year and region of deployment. Additionally, we compared the response of PTSD patients with (n=13) and without co-morbid major depressive disorder (MDD) (n=13).


RESULTS
No significant differences were observed in ACTH and cortisol response to the DEX-CRH test between patients and controls. PTSD patients with co-morbid MDD showed a significantly lower ACTH response compared to patients without co-morbid MDD. The response to the DEX-CRH test did not correlate with PTSD or depressive symptoms.


CONCLUSIONS
The DEX-CRH test did not reveal HPA-axis abnormalities in PTSD patients as compared to trauma controls. PTSD patients with a co-morbid MDD showed an attenuated ACTH response compared to PTSD patients without co-morbid MDD, suggesting the presence of subgroups with different HPA-axis regulation within the PTSD group. Altered sensitivity of the CRH receptors at the pituitary or differences in AVP secretion might explain these differences in response.
de Kloet
Carien
C
Department of Military Psychiatry, Central Military Hospital, Utrecht, The Netherlands. c.de.kloet@altrecht.nl
Vermetten
Eric
E
Lentjes
Eef
E
Geuze
Elbert
E
van Pelt
Johannes
J
Manuel
Remy
R
Heijnen
Cobi
C
Westenberg
Herman
H
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D003346:Corticotropin-Releasing Hormone; D003627:Data Interpretation, Statistical; D003866:Depressive Disorder / Q000150:complications / Q000175:diagnosis* / Q000523:psychology; D003907:Dexamethasone; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology; D008297:Male; D011569:Psychiatric Status Rating Scales; D011965:Receptors, Glucocorticoid / Q000187:drug effects; D013313:Stress Disorders, Post-Traumatic / Q000150:complications / Q000175:diagnosis* / Q000523:psychology; D014728:Veterans
D011965:Receptors, Glucocorticoid; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D006854:Hydrocortisone