Five-year changes in bone density, and their relationship to plasma estradiol and pretreatment bone density, in an older population of postmenopausal women using long-term estradiol implants.
The aim of this study was to observe whether bone mineral density (BMD) improves over 5 years in older women using estradiol implants. A total of 18 women were selected who had commenced hormone replacement therapy (HRT) around the age of 60 years. The median age was 60.9 years (range 59.7-63.2 years). Each woman had a pretreatment bone scan and then received 6-monthly subcutaneous 50 mg estradiol implants. Twelve untreated women were also selected who had had bone scans at baseline and after 5 years. A comparison of the changes in BMD between treated and untreated women was made using the Wilcoxon rank-sum test. All changes at the hip and spine were statistically significant improvements from baseline in the estradiol-treated group. After 5 years of treatment, the estradiol-treated group had significantly improved bone mineral densities compared with the untreated group. At the spine, the plasma estradiol concentration is statistically significantly correlated with the 5-year increase in bone density (r = 0.717, p = 0.004). There was found to be an inverse relationship between the percentage increase in BMD over the 5-year period and initial bone density (r = -0.635, p < 0.005). Thus estrogen is seen to have the effect of improving bone density in older women over 5 years of treatment. The increase in vertebral bone density is most marked in those women with the highest plasma estradiol levels and the lowest pretreatment bone density.
Vashisht
A
A
Academic Department of Obstetrics and Gynaecology, Chelsea and Westminster Hospital, London, UK.
Studd
J W
JW
D015519:Bone Density; D004343:Drug Implants; D004958:Estradiol / Q000008:administration & dosage* / Q000097:blood; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000517:prevention & control*
D004343:Drug Implants; D004958:Estradiol