title: Associations between hypothalamic-pituitary-adrenal axis function and peak bone mass at 20years of age in a birth cohort.
abstract: In older adults, high-normal circulating cortisol levels are associated with lower bone mass, but relationships between hypothalamic-pituitary-adrenal axis function and peak bone mass in young adults have not been examined. We studied 411 male and 390 female participants in the Western Australia Pregnancy Cohort (Raine) Study. At 18years of age, participants underwent a Trier Social Stress Test (TSST) with measurement of plasma and salivary cortisol at baseline and at multiple time points after stress. Cortisol responses were classified as anticipatory responder (significant fall in cortisol during the test), reactive responder (significant increase) or non-responder. At 20years, total body bone mineral content (BMC) and density (BMD) were measured by DXA. In males, after adjustment for weight, height (for BMC and bone area only), alcohol and smoking, there was a significant inverse relationship between both plasma and salivary cortisol measured at baseline in the TSST and each of BMC and BMD, such that each additional 10% of salivary cortisol was associated with reductions of 6.9g (95% CI -11.7, -2.2) in BMC, and 1.8mg/cm(2) (95% CI -3.3, -0.4) in BMD. Males classified as anticipatory responders in the TSST had 3.2% lower BMC (adjusted mean±SE: 3131±28 vs. 3233±18g, P=0.006) and 2.5% lower BMD (1108±9 vs. 1136±6mg/cm(2), P=0.022) than reactive responders. In females, there were no significant relationships between baseline cortisol or TSST responses and BMC or BMD in covariate-adjusted analyses. We conclude that in young males (but not females), higher circulating cortisol at the baseline of the stress test and an anticipatory responder pattern on the TSST are associated with lower total body bone mass.
authors.affiliation: Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, Australia; School of Medicine and Pharmacology, University of Western Australia, Crawley, Australia. Electronic address: kun.zhu@uwa.edu.au.
authors.forename: Kun
authors.initials: K
authors.lastname: Zhu
authors.affiliation: Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, Australia; School of Medicine and Pharmacology, University of Western Australia, Crawley, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Henley
authors.affiliation: School of Women's and Infants' Health, University of Western Australia, Crawley, Australia.
authors.forename: Craig
authors.initials: C
authors.lastname: Pennell
authors.affiliation: School of Women's and Infants' Health, University of Western Australia, Crawley, Australia.
authors.forename: Carly E
authors.initials: CE
authors.lastname: Herbison
authors.affiliation: School of Population Health, University of Western Australia, Crawley, Australia.
authors.forename: Jenny
authors.initials: J
authors.lastname: Mountain
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Canada.
authors.forename: Stephen
authors.initials: S
authors.lastname: Lye
authors.affiliation: Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, Australia; School of Medicine and Pharmacology, University of Western Australia, Crawley, Australia.
authors.forename: John P
authors.initials: JP
authors.lastname: Walsh
mesh_terms: D001842:Bone and Bones / Q000033:anatomy & histology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology*; D008297:Male; D009483:Neuropsychological Tests; D009929:Organ Size; D010913:Pituitary-Adrenal System / Q000502:physiology*; D012044:Regression Analysis; D013315:Stress, Psychological / Q000097:blood / Q000503:physiopathology; D055815:Young Adult
chemical_list: D006854:Hydrocortisone
keywords: Hypothalamic–pituitary–adrenal axis function; Peak bone mass; Raine study; Trier Social Stress Test; Young adults