Beneficial effects of hormonal replacement therapy on chromium status and glucose and lipid metabolism in postmenopausal women

Abstract

Postmenopausal women exhibit an increased incidence of cardiovascular diseases, and type 2 diabetes mellitus compared with younger women. However, women receiving hormonal replacement therapy (HRT) seem to be protected. Since chromium (Cr) functions in glucose, lipid and corticosteroid metabolism and these variables, as well as Cr status, decline with age, Cr status may be a contributing factor in the effects of hormone replacement therapy. Therefore, the objective of this study was to determine the effects of hormonal replacement therapy (HRT) on serum and urinary Cr, plasma lipids, glucose, fructosamine and the related hormonal variables, estradiol, insulin, leptin, cortisol, and DHEA-sulfate. Forty-four healthy postmenopausal women 50-60 years old participated in the study. Eighteen were treated by combined oral hormonal replacement therapy (estradiol 2 mg per day during days 1-25 and 10 mg of dydrogesterone on days 10-25) for at least 2 years, and 26 were untreated. Serum Cr concentrations were significantly lower in untreated postmenopausal women than in women receiving HRT (0.070+/-0.008 vs. 0.100+/-0.008 ng/ml) whereas urinary Cr excretion was increased (0.14+/-0.02 vs. 0.07+/-0.01 ng of Cr/mg creatinine). The urinary losses of Cr were inversely correlated with plasma estradiol. Median value of urinary Cr was higher in postmenopausal women exhibiting endogenous estradiol levels below 250 pmol/l, whereas women with estradiol levels >250 pmol/l, exhibited lower Cr values. Plasma fructosamine, total and LDL cholesterol and TC/HDL ratio, which are all decreased by improved Cr nutrition, were also improved in the women receiving HRT. There were also nonsignificant decreasing trends in DHEA-sulfate (P<0.06) and cortisol (0.07). Chromium status, based upon blood and urinary analyses, and glucose, insulin and lipid variables were improved in postmenopausal women receiving HRT. Additional studies are needed to determine if improved Cr status due to supplemental Cr can elicit effects consistent with those of hormone replacement therapy.