Bone-Sparing by Ca Salts With & Without Extra Phosphorus

描述：（由申请人提供）骨矿物质基本上是磷酸钙，两种元素（Ca和P）都是骨获取所必需的。在美国，典型的钙摄入量低于目前的建议，而典型的磷摄入量则高于目前的建议。因此，人们的注意力主要集中在通过补充和食品强化来增加钙的摄入量。最常用于这些目的的盐是碳酸钙。但是，虽然平均磷摄入量往往是足够的或慷慨的，但相当大比例的老年妇女在任何一天摄入的磷少于RDA的70%，因此可以说是处于磷缺乏的风险之中。当这些妇女给予合成代谢治疗和补充钙（作为碳酸盐）的组合时，增加的钙可能会发现并加重潜在的磷缺乏症。这是因为Ca在肠道中结合磷酸盐并减少其吸收（从而进一步有效地降低P摄入），并且因为诱导的骨吸收剂本身将消耗磷，因此吸收的磷可能不足以支持通过这种疗法可能实现的骨矿物质质量的增加。 为了测试补充骨矿物质的两种成分在支持骨质疏松症的合成代谢治疗中的可能的重要性和价值，我们提出了一项为期1年的随机试验，在两组特立帕肽治疗的绝经后骨质疏松症妇女中，比较钙补充剂与不含额外磷（即，磷酸钙对碳酸钙）。主要的结果测量将是在一年的试验中骨矿物质含量的变化。次要结果是测量骨吸收生物标志物，以评估磷酸盐是否相对于碳酸盐提高了重塑。 含磷酸盐钙补充剂的优越性的发现将提供证据，导致钙来源的成本中性变化和骨质疏松症联合治疗（以及可能的骨质疏松症预防）的相应改善。

DESCRIPTION: (provided by applicant) Bone mineral is basically calcium phosphate, and both elements (Ca and P) are required for bone acquisition. Typical Ca intakes in the U.S. are lower than current recommendations, and typical P intakes, higher. Thus attention has been focused mainly on increasing Ca intake, by supplementation and food fortification. The salt most commonly used for these purposes is calcium carbonate. But while the average P intake tends to be adequate or generous, nevertheless substantial proportions of older women ingest less than 70 percent of the RDA for phosphorus on any given day, and hence may be said to be at risk for P deficiency. When these women are given a combination of anabolic therapy and supplemental Ca (as the carbonate), the added Ca may uncover and aggravate the latent P deficiency. This is both because Ca binds phosphate in the gut and reduces its absorption (thereby effectively lowering the P intake still further) and because the induced bone anabolism will itself consume phosphorus, as a result of which absorbed phosphorus may not be sufficient to support the increase in bone mineral mass made possible by this therapy. To test the possible importance and value of supplementing both of the components of bone mineral in support of anabolic therapy of osteoporosis, we propose a 1-year randomized trial, comparing, in two groups of teriparatide-treated postmenopausal osteoporotic women, calcium supplements with and without extra phosphorus (i.e., Ca phosphate vs. Ca carbonate). The principal outcome measure will be change in bone mineral content over the one year of the trial. A secondary outcome is measurement of bone resorption biomarkers so as to assess whether the phosphate salt elevates remodeling relative to the carbonate salt. A finding of superiority of the phosphate-containing Ca supplement would provide evidence leading to a cost-neutral change in Ca sources and a corresponding improvement in osteoporosis co-therapy (and possibly osteoporosis prophylaxis as well).