Serotonin dilemma in postmenopausal women: is it low or high?

OBJECTIVE

In this study, we have studied with premenopausal (PM), naturally menopausal (NM) and surgically induced menopausal (SM) women in order to investigate the differences in serum cortisol, dehydroepiandrosterone sulfate (DHEA-S), follicle stimulating hormone (FSH) and estradiol (E2) levels on serum serotonin levels.

METHODS

Forty premenopausal (36.7+/-3.5 years), 40 naturally menopausal (54.2+/-8.4 years) and 38 surgically induced menopausal (55.4+/-11.2 years) women were included in the study. None of the subjects were using antidepressants or hormone replacement therapy. In NM and SM, years since menopause (YSM) were 3.16+/-1.58 and 3.36+/-1.89, respectively. Cortisol, DHEA-S, FSH and E2 levels were determined by immunochemiluminisence while serotonin levels were determined by HPLC.

RESULTS

Serum serotonin levels in NM women were higher than the other two groups [144.23+/-45.29 microg/L vs 61.35+/-37.72 microg/L in SM women and 98.74+/-50.29 microg/L in PM women]. E2 and DHEA-S were positively correlated, while FSH and cortisol were negatively correlated with serotonin in NM and SM. There was no significant correlation between serotonin and age or YSM. In the PM group, there was no significant correlation between serotonin and the hormones.

CONCLUSION

In conclusion, increased serotonin levels in naturally menopausal women may be a compensatory mechanism to decreased E2 levels as it is postulated that there is strong interaction between E2 and the serotoninergic system.