Background: Melatonin is known for its regulation of circadian rhythm. The production falls with age, which explains why elderly may have disturbed sleep patterns. Laboratory study and animal experimental studies suggests that melatonin also may protect against bone loss through increased osteoblast- and inhibited osteoclast activity. However, so far human studies have not been performed.~Design and patients: Double blinded randomised controlled study. Eighty post-menopausal women (aged 55-75) with osteopenia are randomized to receive 1mg, 3mg or placebo (daily - at night time) for 12 months.~Methods and results: Effects of melatonin on BMD, bone- structure and mass will be assessed through DXA-scans, pQCT, and QCT. Quality of life, sleep, and activity level will be assessed though questionnaires. Calcium homeostasis will be analyzed through blood and urines samples. As safety parameters, balance and muscle function will also be performed.~Conclusion: Expected improvements in BMD, quality of life and sleep.
The aim of the study is to assess the effect of melatonin treatment in patients with osteopenia on BMD, muscle function, quality of life and calcium homeostasis.