Effects of six months melatonin treatment on sleep quality and serum concentrations of estradiol, cortisol, dehydroepiandrosterone sulfate, and somatomedin C in elderly women.

OBJECTIVES: The role of melatonin is aging is still under debate. Therefore, an open pilot study on the effects of melatonin administration on some sleep parameters, routine hematological and biochemical parameters, and concentrations of hormones was performed in elderly women.

SUBJECTS AND METHODS: The study was performed on 14 women (volunteers), aged from 64 to 80 years (mean age 71+/-4.6 years). Melatonin (2 mg daily at 19:00 h) was administered during 6 months. Before and after melatonin treatment the peripheral venous blood samples were taken in the morning (approx. at 08:00 h) after the overnight fast. The total blood count, glucose, total cholesterol, LDL, HDL, and triglycerides were estimated by routine laboratory methods. The serum concentrations of the following hormones were determined: 17-beta-estradiol, dehydroepiandrosterone sulfate (DHEAS), cortisol, and somatomedin C (IGF-I). Additionally, before and after 6 months of melatonin therapy the investigated subjects answered to a questionnaire dealing with sleep parameters and self-estimation of general health status.

RESULTS: In 35.7% of investigated subjects an improvement in general sleep quality and in such sleep parameters as sleep initiation, sleep latency, number of awakenings episodes, wake time after sleep onset, was observed. A significant decrease of estradiol concentrations was observed after 6 months of the melatonin treatment in comparison to initial levels. IGF-I was found to be slightly but significantly increased after the 6 months melatonin therapy. Cortisol levels did not change significantly, during the melatonin treatment. DHEAS concentrations increased after melatonin therapy. Moreover, a tendency towards a higher DHEAS/cortisol ratio was found after 6 months of treatment. Melatonin treatment did not influence significantly either the parameters of total blood count or glucose and serum lipids levels.

CONCLUSIONS: On the basis of this preliminary open study it seems that melatonin administration may be beneficial for elderly subjects.