Serum sex hormone-binding globulin, cardiovascular risk factors, and adrenal cortisol responses to dexamethasone and corticotropin.
Basal cortisol levels and cortisol responses to dexamethasone (DXM) and corticotropin were studied in relation to serum levels of sex hormone-binding globulin (SHBG), testosterone (T), free T, estradiol (E2), insulin-like growth factor I (IGF-I), high-density lipoprotein cholesterol (HDLC), triglycerides (TG), and insulin in 30 men. SHBG was positively correlated to age (P < .01), HDLC (P < .05), and total T (P < .05) and negatively correlated to TG (P < .02) and insulin (P < .001). SHBG was inversely related to corticosteroid-binding globulin (P < .05), but was not significantly associated with IGF-I. Free T was positively related to TG (P < .05), insulin (P < .01), total T (P < .001), and basal (P < .01) and free cortisol (P < .05). Corticotropin-stimulated cortisol responses were negatively associated with SHBG (P < .001) and positively associated with insulin (P < .01). Multiple linear regression analyses with SHBG as the dependent variable indicated that cortisol response alone explained 34.0% and together with age 46.2% of the variation of SHBG levels. Only insulin and age, but not cortisol response, remained significant predictors of SHBG concentrations when entered simultaneously into the mathematical model; this model explained 55.1% of the variation of SHBG levels. Thus, in addition to insulin and age, cortisol reserves and secretion seem to have significant associations with serum SHBG and free T concentrations.
Department of Clinical Chemistry, University of Helsinki, Finland.
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A
Hautanen
S
S
Sarna
R
R
Pelkonen
H
H
Adlercreutz
D000302:Adrenal Cortex / Q000187:drug effects / Q000378:metabolism; D000324:Adrenocorticotropic Hormone; D000328:Adult; D003327:Coronary Disease / Q000209:etiology*; D003907:Dexamethasone; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012307:Risk Factors; D012738:Sex Hormone-Binding Globulin / Q000032:analysis*; D013739:Testosterone / Q000097:blood
D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone