Hormone replacement therapy may reduce the return of endogenous lead from bone to the circulation
- McMaaster Univ., Hamilton, Ontario (Canada); and others
Hormone replacement therapy (HRT) in postmenopausal women suppress the increase in bone resorption expected as circulating levels of endogenous estrogen decline. We tested the hypothesis that bone lead content might remain elevated in women on HRT. Fifty-six women who at recruitment were on average 3.5 years postmenopausal were placed on calcium supplementations. Six months later, 33 of these women were prescribed either low dose or moderate dose hormone replacement in addition to the calcium supplementation. After approximately 4 years of hormone replacement, lead content was measured at the tibia and calcaneus by in vivo fluorescence excitation, and lead concentrations were measured in serum, whole blood, and urine. Women not taking hormones had significantly lower lead concentrations in cortical bone compared to all women on HRT (p=0.007). Tibia lead content (mean {plus_minus} SD) for women on calcium only was 11.13 {plus_minus}6.22 {mu}g/g bone mineral. For women on HRT, tibia bone lead was 19.37 {plus_minus}8.62 {mu}g/g bone mineral on low-dose HRT and 16.87 {plus_minus} 11.68 {mu}g/g bone mineral on moderate-dose HRT. There were no differences between groups for lead concentrations measured in trabecular bone, whole blood, serum, or urine. Hormone replacement maintains cortical bone lead content. In women not on HRT, there will be a perimenopausal release of lead from bone. 27 refs., 1 fig., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 391056
- Journal Information:
- Environmental Health Perspectives, Vol. 103, Issue 12; Other Information: PBD: Dec 1995
- Country of Publication:
- United States
- Language:
- English
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