The aim of this study was to determine the effect of hormone replacement therapy (HRT) on changes in circulating dehydroepiandrosterone-sulphate (DHEA-S) with focus on the relationship between oestrogen level and change in DHEA-S. Forty-two women were enrolled in this longitudinal study. Nineteen women received oral oestradiol and twenty-three women received transdermal oestradiol continuously. Twenty women received progesterone continuously except for women who had undergone hysterectomy. Circulating oestradiol, follicle-stimulating hormone, luteinising hormone and DHEA-S levels before and at 3 months after commencement of HRT were measured. Circulating DHEA-S level was significantly decreased at 3 months (p < .001). Oestradiol level at 3 months ranged from 6.5 pg/ml to 159 pg/ml. There was no significant correlation of ΔDHEA-S (DHEAS level at 3 months-DHEA-S level at baseline) with Δoestradiol (r = 0.114, p = .471). Circulating DHEA-S level was significantly decreased at 3 months in all the four quartiles and divided according to Δoestradiol, and ΔDHEA-S did not show significant differences. In conclusion, circulating DHEA-S decreases even with a slight increase in oestradiol level. Impact statement What is already known on this subject: A transient increase in DHEA-S in women during the menopausal transition may be involved in the occurrence of menopausal symptoms and/or unfavourable metabolic changes. Hormone replacement therapy decreases circulating DHEA-S level. However, dose dependency of the change in DHEA-S on oestrogen has not been reported. What the results of this study add: Circulating DHEA-S decreases even with a slight increase in oestradiol level. What the implications are of these findings for clinical practice and/or further research: Adrenal function may respond to a small change in oestrogen.
Keywords: Dehydroepiandrosterone-sulphate (DHEA-S); menopausal transition; oestradiol.