Hypothalamic-pituitary-adrenal axis activity and sleep in posttraumatic stress disorder.
Alterations of the hypothalamic-pituitary-adrenal (HPA) axis and sleep disturbances have been described separately in post-traumatic stress disorder (PTSD). It is not known if HPA alterations and sleep disturbances are associated in PTSD. This study examined sleep and HPA activity in 20 male medication-free subjects with PTSD and 16 matched healthy controls. Two nights of polysomnography were obtained and 24-h urinary cortisol was collected during day 2. Subjects self-administered a low-dose (0.5 mg) salivary dexamethasone test at home. Compared with controls, PTSD subjects had higher 24-h urinary microg cortisol/g creatinine (mean+/-SD 40+/-17 vs 28+/-12, p=0.03) but not significantly higher 24-h urinary cortisol (mean+/-SD 52+/-15 microg/day vs 43+/-23, p=0.19). PTSD subjects showed a trend towards less cortisol suppression after dexamethasone (73%+/-18 vs 83%+/-10, p=0.06). In the combined sample, delta sleep was significantly and negatively correlated with 24-h urinary cortisol (r=-0.36, p=0.04), and with 24-h urinary cortisol/g creatinine on a trend level (r=-0.34, p=0.06). Our results suggest that increased cortisol is negatively associated with delta sleep. This may contribute to sleep abnormalities in conditions associated with elevated cortisol, possibly including PTSD. Future studies should explore the temporal relationship between HPA activity, sleep disturbances, and psychopathology after a traumatic event.
Otte
Christian
C
Department of Psychiatry, University of California, San Francisco, CA, USA.
Lenoci
Maryann
M
Metzler
Thomas
T
Yehuda
Rachel
R
Marmar
Charles R
CR
Neylan
Thomas C
TC
D000328:Adult; D003404:Creatinine / Q000652:urine; D003700:Delta Rhythm; D003907:Dexamethasone / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism / Q000652:urine; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010913:Pituitary-Adrenal System / Q000503:physiopathology*; D017286:Polysomnography; D011569:Psychiatric Status Rating Scales; D012463:Saliva / Q000378:metabolism; D012890:Sleep / Q000502:physiology*; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology* / Q000523:psychology*
D003907:Dexamethasone; D003404:Creatinine; D006854:Hydrocortisone