Relationship between bone mineral loss and urinary fluoride concentration in postmenopausal Japanese women

The purpose of this study was to evaluate the relationship between bone mineral loss and urinary fluoride (F) concentration in postmenopausal Japanese women. Lumbar spinal bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA) at baseline and 1 year later in 94 premenopausal and 100 postmenopausal women. None of the subjects had any bone-related disorders. There were significant correlations between urinary F concentration and time since menopause (r = 0.397; P < 0.05), and between annual BMD loss and urinary F concentration at baseline (r = -0.492; P < 0.01) in the postmenopausal women. However, there was no significant correlation between urinary F concentration and BMD either at baseline or 1 year later. Urinary F concentration tended to be higher in postmenopausal women with low blood estradiol (E(2)) concentration than in those with normal blood E(2) concentration. Our results suggested that urinary F concentration may be a useful marker to assess bone resorption in postmenopausal women.