PREVENTION OF AGE-RELATED BONE LOSS WITH CALCIUM THERAPY

该项目包括一个持续4年的前瞻性、双重约束、安慰剂- 236例老年人补钙临床对照试验 进入时年龄在61岁至70岁之间且至少10岁的女性 绝经后。临床试验是独一无二的，因为它是以人群为基础的， 参与者是通过对这个年龄组进行筛查获得的 明尼苏达州奥姆斯特德县的全部人口。在提交时，它是 估计需要长达2年的时间来筛选3,013个潜在的 有资格的妇女和招募的参与者参加试验，并且 需要延期才能完成。事实证明，这是 案例，我们要求延期一年。的核心假说 这项试验的基础是骨量减少的一个主要原因 老年妇女是补钙。我们的主要研究目标是 确定补钙对骨丢失的影响，以及我们的继发性 研究的目标是确定这是否与减少 甲状旁腺功能和骨转换，并确定副作用和 这些老年妇女对补钙的患者可接受性。这个 参与者被随机分为治疗组和对照组；受试者 在治疗中，肢体每天接受1600毫克的钙(如柠檬酸钙)和那些 在对照肢体中，接受了与之匹配的安慰剂。受试者是 在基线上进行评估，并在治疗期间每6个月检查一次 治疗依从性评估和骨密度测量 (腰椎、股骨近端和整个骨骼) 骨吸收测定、骨转换生化标记物(血清骨钙素、 骨碱性磷酸酶和尿吡啶交联物)，以及 甲状旁腺功能(血清完整甲状旁腺激素和尿液 营地)。重要的是要完成整个4年的试验，以便 有足够的统计能力明确解决中心问题 而且，因为一些研究表明治疗效果会减弱 在1年后，要确定任何有益效果长期保持- 学期。考虑到对合问题的巨大规模 骨质疏松症，唯一经济有效的方法是预防。干预 补钙是一个有吸引力的选择，因为与 其他可用的预防骨质流失的药物，它是相对 低成本和安全，以及大规模干预策略，例如 食物的防御工事，可以使用。然而，在这样的全国范围内 可以推荐方案，应该提供更明确和严谨的数据 获得支持长期疗效和安全性的，如那些 从这项临床试验中衍生出来。

This project comprises an ongoing 4-year prospective, double-bind, placebo- controlled clinical trial of calcium (Ca) supplementation in 236 elderly women who were 61 to 70 yrs of age at entry and at least 10 yrs postmenopausal. The clinical trial is unique as it is population-based, and the participants were obtained by screening this age-group in the entire population of Olmsted County, MN. At the time of submission, it was estimated that it would take up to 2 yrs to screen the 3,013 potentially eligible women and recruit participants into the trial and that an extension would be required to complete it. This has proved to be the case, and we are requesting a 1-yr extension. The central hypothesis upon which the trial is based is that a major etiologic factor for bone loss in elderly women is Ca supplementation. Our primary study objective is to determine the effect of Ca supplementation on bone loss, and our secondary study objectives are to determine if this is associated with a decrease in parathyroid function and in bone turnover and to determine side effects and patient acceptability of Ca supplementation in these elderly women. The participants were randomized into treatment and control limbs; the subjects in the treatment limb received 1,600 mg/day of Ca (as Ca citrate) and those in the control limb received a matching placebo. The subjects were evaluated at baseline and are seen every 6 months during treatment for assessment of therapeutic compliance and measurement of bone density (lumbar spine, proximal femur, and whole skeleton) by dual photon absorptiometry, biochemical markers for bone turnover (serum osteocalcin, bone alkaline phosphatase, and urinary pyridinium cross-links), and parathyroid gland function (serum intact parathyroid hormone and urinary cAMP). It is important to complete the full 4 yrs of the trial to have sufficient statistical power to resolve the central issue unequivocally and, because some studies have suggested a waning of the therapeutic effect after 1 yr, to establish that any beneficial effect is maintained long- term. Given the enormous magnitude of the problem of involutional osteoporosis, the only cost-effective approach is prevention. Intervention with Ca supplementation is an attractive option because, in contrast with other available drugs for the prevention of bone loss, it is relatively inexpensive and safe, and mass interventive strategies, such as Ca fortification of food, could be employed. However, before such nation-wide programs could be recommended, more definitive and rigorous data should be obtained supporting long-term efficacy and safety, such as those to be derived from this clinical trial.