ABSTRACT
OBJECTIVES: To investigate the effect of transvaginal estradiol on bone mineral density and bone metabolism. METHODS: One hundred and fifteen women (mean age 73.8+/-3.2 years) were randomly assigned to a 2-year open-label parallel group clinical trial and were treated with either transvaginal estradiol (7.5 microg/24h), or no estradiol. Both groups received 400 IU vitamin D and 500 mg calcium/day. The bone mineral density (BMD) was assessed in the hip and spine using DXA technique and in the heel using DXL technique. RESULTS: The intention to treat analysis showed that the increase in BMD in the estradiol group was significant at total hip by 0.6% (P=0.04) while the control group decreased in their BMD by 0.7%. At lumbar spine the estradiol group increased in BMD by 2.6% (P=0.011) while the control group increased by 2.2%. Bone turnover markers and PTH-levels decreased while 25-OH vitamin D levels increased in both groups, a probable effect of the calcium and vitamin D supplementation. The bone resorption marker CTx decreased more significantly in the treatment group (P=0.016). CONCLUSIONS: The transvaginal estradiol treatment of 7.5 microg/24h had a small but significant effect on the BMD of total hip and lumbar spine after a follow-up of 2 years.
