Relationship between calcium absorption and plasma dehydroepiandrosterone sulphate (DHEAS) in healthy males.
BACKGROUND
Impaired gut sensitivity to 1,25-dihydroxyvitamin D (1,25(OH)(2)D), leading to reduced intestinal calcium absorption, has been reported in older men and women. While this phenomenon in postmenopausal women has been attributed to oestrogen deficiency, it is unclear whether the same observation in older men correlates with the age-related decline in androgen concentrations.


OBJECTIVE
To examine the relationship between androgens and intestinal calcium absorption in older men.


METHODS
Cross-sectional study on 55 healthy male volunteers, divided into younger (n = 27) and older (n = 28) groups separated according to the median age of 59 years.


METHODS
Calcium absorption, total and free (calculated) testosterone, dehydroepiandrosterone sulphate (DHEAS), SHBG, and 1,25(OH)(2)D, among others, were measured.


RESULTS
Calcium absorption, free testosterone and DHEAS, but not 1,25(OH)(2)D, declined significantly with age. After adjusting for age and body mass index, stepwise regression showed that 1,25(OH)(2)D and serum albumin were the only significant determinants of calcium absorption in younger men, while the sole determinant in older men was DHEAS, not testosterone. Residual deviations from the regression of calcium absorption on 1,25(OH)(2)D, reflecting the efficiency of 1,25(OH)(2)D-induced calcium absorption, was positively correlated with DHEAS (r = 0.27, P = 0.027).


CONCLUSIONS
DHEAS is an independent determinant of calcium absorption in older men, although its manner of influence is, as yet, undefined. The age-related decline of DHEAS may, partly, account for the observed 'intestinal resistance to 1,25(OH)(2)D' in older men.
Chen
R Y T
RY
Department of Medicine, Changi General Hospital, Singapore. chenyt10@hotmail.com
Nordin
B E C
BE
Need
A G
AG
Scopacasa
F
F
Wishart
J
J
Morris
H A
HA
Horowitz
M
M
D000328:Adult; D000368:Aged; D002136:Calcium, Dietary / Q000378:metabolism*; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood*; D006801:Humans; D007408:Intestinal Absorption; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013739:Testosterone / Q000097:blood; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood
D002136:Calcium, Dietary; D012738:Sex Hormone-Binding Globulin; D014807:Vitamin D; D013739:Testosterone; D019314:Dehydroepiandrosterone Sulfate; C097949:1,25-dihydroxyvitamin D