Central hypothalamic-pituitary-adrenal activity and the metabolic syndrome: Studies using the corticotrophin-releasing hormone test.
A number of studies have suggested that the metabolic syndrome (principally, the combination of hypertension, glucose intolerance, and dyslipidemia) is associated with subtle dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis leading to raised circulating cortisol concentrations. The mechanisms underlying these observations are not known. We assessed the salivary cortisol response to awakening and pituitary-adrenal responses during a 100-microg human corticotrophin-releasing hormone (CRH) test and a dexamethasone-suppressed CRH test in a well-characterized group of 65-year-old men (n = 122). In the cohort from which this subgroup was drawn, there were associations between the components of the metabolic syndrome and 9 am cortisol concentration in line with previous studies. However, there were no significant associations between blood pressure, glucose tolerance, and lipid concentrations and the dynamic tests of HPA activity. We therefore found no evidence to suggest that exaggerated pituitary responsiveness or increased central drive to the pituitary, as determined by CRH testing, plays a part in the development of the metabolic syndrome.
Ward
Alexandra M V
AM
MRC Environmental Epidemiology Unit, University of Southampton, Southampton General Hospital, Southhampton, UK.
Syddall
Holly E
HE
Wood
Peter J
PJ
Dennison
Elaine M
EM
Phillips
David I W
DI
D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology / Q000378:metabolism; D015331:Cohort Studies; D003346:Corticotropin-Releasing Hormone / Q000037:antagonists & inhibitors / Q000378:metabolism*; D003907:Dexamethasone / Q000494:pharmacology; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D008659:Metabolic Diseases / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology / Q000378:metabolism / Q000503:physiopathology; D010913:Pituitary-Adrenal System / Q000378:metabolism* / Q000503:physiopathology; D012307:Risk Factors; D012463:Saliva / Q000737:chemistry / Q000378:metabolism; D018709:Statistics, Nonparametric; D014851:Wakefulness / Q000502:physiology
D003907:Dexamethasone; D003346:Corticotropin-Releasing Hormone; D006854:Hydrocortisone