Low Dose Estrogen and Calcium Have an Additive Effect on Bone Resorption in Older Women1
Open Access
- 1 January 1999
- journal article
- clinical trial
- Published by The Endocrine Society in Journal of Clinical Endocrinology & Metabolism
- Vol. 84 (1), 179-183
- https://doi.org/10.1210/jcem.84.1.5416
Abstract
Previous studies have shown that treatment with estrogen or calcium decreases bone turnover in older women. The mechanisms by which estrogen and calcium exert their effects are probably different. We therefore examined the possibility of an additive or synergistic effect of combined treatment with calcium and low dose estrogen on bone turnover in older women, using biochemical markers. Thirty-one healthy women over 70 yr of age were randomized to 12 weeks of treatment with either micronized 17β-estradiol [0.5 mg/day Estrace (E2)] or 1500 mg/day elemental calcium, given as carbonate plus vitamin D (800 IU/day; Ca+D). At the end of the initial 12-week treatment period, both groups received both Ca+D and E2 for an additional 12 weeks. Eleven older women were followed for 36 weeks without any treatment and served as a control group. Serum and urine were collected at baseline, at 12 and 24 weeks on treatment, and at 12 weeks after treatment was terminated for measurement of biochemical markers of bone turnover. Markers of bone formation were bone alkaline phosphatase, osteocalcin, and type I procollagen peptide; markers of bone resorption were urinary cross-linked C-telopeptides and N-telopeptides of type I collagen, serum cross-linked N-telopeptides of type I collagen, urinary free deoxypyridinoline cross-links, and serum bone sialoprotein. Repeated measures ANOVA was used to determine changes in bone turnover measures over time by group. All markers of bone resorption decreased with initial treatment and decreased further with combination therapy (P < 0.001). Markers of bone formation decreased with Ca+D treatment, but not with E2 alone; there was no additional effect of combination therapy on formation markers compared to Ca+D alone. Neither markers of formation nor resorption changed in the control group. These results suggest that there is an additive effect of low dose estrogen and calcium on bone resorption, but not on bone formation, in older women. Thus, the combination of low dose estrogen plus calcium is likely to be more effective in older women than either treatment alone.Keywords
This publication has 17 references indexed in Scilit:
- Effect of Calcium and Vitamin D Supplementation on Bone Density in Men and Women 65 Years of Age or OlderNew England Journal of Medicine, 1997
- Hormone Replacement Therapy in Postmenopausal Women: Urinary N-Telopeptide of Type I Collagen Monitors Therapeutic Effect and Predicts Response of Bone Mineral DensityAmerican Journal Of Medicine, 1997
- Estrogen Replacement Therapy and Fractures in Older WomenAnnals of Internal Medicine, 1995
- Effect of Calcium Supplementation on Bone Loss in Postmenopausal WomenNew England Journal of Medicine, 1993
- Vitamin D3and Calcium to Prevent Hip Fractures in Elderly WomenNew England Journal of Medicine, 1992
- The Prevention and Treatment of OsteoporosisNew England Journal of Medicine, 1992
- A Controlled Trial of the Effect of Calcium Supplementation on Bone Density in Postmenopausal WomenNew England Journal of Medicine, 1990
- A randomized study on the effects of estrogen/gestagen or high dose oral calcium on trabecular bone remodeling in postmenopausal osteoporosisBone, 1989
- Does Calcium Supplementation Prevent Postmenopausal Bone Loss?New England Journal of Medicine, 1987
- Involutional OsteoporosisNew England Journal of Medicine, 1986