The Study of Muscle and Physical Performance in African Caribbeans

项目摘要/摘要： 补充资金要求购买一台二手的霍奇地平线双X射线吸收测量仪(DXA) 用于多巴哥健康研究(THS)诊所的机器。我们收集了一系列的DXA图像来测量身体 在THS中工作了20年(4次访问)，我们的HOLOGIC 4500W DXA机器出现了故障 在父拨款(R01AG074956)的审查过程中，不再处于工作状态。这台机器 于2000年制造，已由霍洛奇公司停产，并提供维修机器所需的部件 不再可用。QDR 4500W是FDA批准的系统，必须在工厂进行校准 标准，并由医学物理学家验证--这是不可能的。我们在这方面没有做预算。 R01AG074956，因为机器在提交时以及在 审核期。该方案的DXA的主要目的是测量全身和附件脂肪 与成本较低的脂肪块方法相比，使用最初建议的DXA方法有几个优点。 首先，改用BIA将意味着自2000年以来一直在进行的一系列DXA措施的结束，以及 用于计算无价的纵向变化数据。其次，尽管最近进行了审查，DXA仍被考虑 这是衡量瘦体重和脂肪质量的“黄金标准”，几乎包含在所有的“骨量减少症”定义中。 出于这个原因，DXA已经并正在被许多研究用来分割瘦肉和脂肪团。因此， 继续使用DXA将提供与其他人群进行直接比较的宝贵机会。 第三，在测量脂肪质量方面，DXA比BIA更准确，并已被用于评估BIA的准确性。 最后，本研究中测量全身骨骼肌质量的主要指标是D3cr，虽然该方法 在MROS研究中显示与身体机能有更强的关系，这些比较 不是在其他人群中制造的。因此，按照最初的提议，列入DXA将大大 加强家长R01的目标和科学贡献。

Project Summary/Abstract: Supplemental funding is requesting to purchase a preowned Hologic Horizon Dual X-ray Absorptiometry (DXA) Machine for the Tobago Health Studies (THS) Clinic. We have collected serial DXA images to measure body composition in the THS for 20 years (4 visits), and the Hologic 4500W DXA machine we have malfunctioned during the review process of the parent grant (R01AG074956) and is no longer in working order. The machine was manufactured in 2000 and has been discontinued by Hologic and the parts required to repair the machine are no longer available. The QDR 4500W is an FDA approved system and must be calibrated to factory standards and validated by a medical physicist – which is not possible. We did not budget for this in R01AG074956, as the machine was in good working order at the time of submission and during most of the review period. The primary purpose of DXA for this proposal was to measure total body and appendicular fat mass and using DXA as originally proposed has several advantages over less expensive methods of fat mass. First, switching to BIA will mean the end of the serial DXA measures that have been ongoing since 2000, and used to calculate invaluable longitudinal change data. Second, despite recent scrutiny, DXA is still considered a “gold standard” for measuring lean and fat mass and is included in just about all definitions of “sarcopenia”. For this reason, DXA has been and is being used by many studies to segment lean and fat mass. Thus, the continued use of DXA would provide the invaluable opportunity for direct comparisons with other populations. Third, DXA is more accurate than BIA for measuring fat mass and has been used to evaluate BIA's accuracy. Finally, the primary measure of total body skeletal muscle mass in this study is D3Cr, and while this method has shown to have stronger relationships with physical function in the MrOS study, these comparisons have not been made in other populations. Thus, the inclusion of DXA, as originally proposed, would significantly enhance the aims and scientific contributions of the parent R01.