Salivary cortisol concentrations before and after carbon-dioxide inhalations in children.
BACKGROUND
Considerable research implicates over-activity of the hypothalamic-pituitary adrenal axis in the pathophysiology of adult mood and anxiety disorders. The current study evaluates the association between salivary cortisol concentrations and response to carbon-dioxide inhalation in children and adolescents with anxiety disorders, mood disorders, or no psychiatric illness. The central question was whether response to carbon-dioxide inhalation is associated with levels of hypothalamic-pituitary adrenal axis activation. If confirmed, this would relate hypothalamic-pituitary adrenal axis activation in juveniles, as in adults, and response to a well-studied respiratory procedure.


METHODS
Serial salivary cortisol samples were examined in 98 subjects (ages 9-17 years), including 62 subjects with an anxiety and/or mood disorder and 36 nonpsychiatrically ill comparisons. Samples were obtained upon arrival at the laboratory, following a tilt test, then before and immediately after a standard 5% carbon dioxide inhalation procedure.


RESULTS
Salivary cortisol levels pre-carbon-dioxide inhalation were significantly higher in patients sensitive to the anxiogenic effects of carbon dioxide (n = 20) than in patients who did not respond to carbon dioxide (n = 42) and in healthy subjects, none of whom were sensitive to carbon dioxide (n = 36); cortisol concentrations in the latter two groups were indistinguishable. Salivary cortisol did not increase during carbon-dioxide inhalation, irrespective of diagnostic group or degree of reactivity to the procedure.


CONCLUSIONS
The current data resemble data from studies of laboratory-induced panic among adult patients. In both groups, activation of the hypothalamic-pituitary adrenal axis is associated with the response to a standardized stressor. Similarly, as in adults, carbon-dioxide inhalation in juveniles does not produce a significant change in hypothalamic-pituitary adrenal axis activation.
Coplan
Jeremy D
JD
Department of Psychiatry, SUNY-Downstate, Brooklyn, NY, USA.
Moreau
Donna
D
Chaput
France
F
Martinez
Jose M
JM
Hoven
Christina W
CW
Mandell
Donald J
DJ
Gorman
Jack M
JM
Pine
Daniel S
DS
D000280:Administration, Inhalation; D000293:Adolescent; D000704:Analysis of Variance; D001008:Anxiety Disorders / Q000188:drug therapy / Q000378:metabolism*; D002245:Carbon Dioxide / Q000008:administration & dosage*; D002648:Child; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D012463:Saliva / Q000378:metabolism*
D002245:Carbon Dioxide; D006854:Hydrocortisone