Low Magnitude Mechanical Stimulation to Improve BMD

描述（申请人提供）：老年人骨折的预防主要集中在抑制骨吸收的药物干预上。我们正在进行的低强度机械刺激（LMMS）的随机、双盲、安慰剂对照试验（称为“VIBES”试验）的基础是，需要采用非药物方法来改善整个肌肉骨骼系统，并最终降低骨折风险。该试验于2007年启动，旨在研究LMMS对骨骼的影响，从最初的200名老年参与者中随机抽取174名，依从率为80%。在这篇续篇中，我们建议将研究干预和随访再延长一年，并通过考虑与肌肉骨骼健康相关的更广泛的测量来扩大科学的范围，包括肌肉面积、密度、力量以及姿势稳定性。这也将增加我们对主要骨骼结果的能力，如果试验不再继续一年，这将只有41%。该试验的DSMB建议不要取消当前研究的任何方面的盲性，并支持扩展VIBES试验。本临床试验的首要假设是LMMS对独立生活的老年人的骨骼、肌肉和姿势稳定性有良好的影响。因此，该项目的第一个目标是通过评估髋部和脊柱体积小梁骨矿物质密度（vTBMB）的连续定量计算机断层扫描（QCT）测量，在三年的时间内确定LMMS对骨骼的影响，这些老年人已经参加了最初的两年研究。在试验期间，我们开发了新的方法来检查我们髋关节的肌肉面积和密度的QCT扫描，并收集了最初未包括在试验中的其他措施，即下肢肌肉力量和使用平衡平台的姿势稳定性。这提供了第二个目标所依据的数据。我们假设LMMS会导致肌肉面积、密度和力量的改善，并会改善平衡。正在进行的试验在老年社区中已经很好地建立起来，研究小组有一个成功的跟踪记录，并且迄今为止没有安全问题。因此，现在有机会将试验再进行一年，并测试围绕这种独特的非药物干预的多种假设。

DESCRIPTION (provided by applicant): The prevention of fractures in the aged population is largely focused on pharmacologic interventions that inhibit bone resorption. The need for non-pharmacologic approaches to improve the musculoskeletal system as a whole and ultimately reduce the risk for fracture, forms the basis for this competing continuation of our ongoing randomized, double-blind, placebo-controlled trial of low magnitude mechanical stimulation (LMMS) called the "VIBES" trial. This trial, initiated in 2007 to study the skeletal effects of LMMS, has randomized 174 of the originally targeted 200 elderly participants with an adherence rate of 80%. In this continuation, we propose to extend the study intervention and follow up by one additional year, and to expand the scope of the science by considering a broader range of measures relevant to musculoskeletal health, including muscle area, density, and strength, as well as postural stability. This will also increase our power for the primary skeletal outcomes, which will be only 41% if the trial does not continue one additional year. The DSMB for the trial has recommended not unblinding any aspect of the current study, and is supportive of the extension to the VIBES trial. The overarching hypothesis of this clinical trial is that LMMS will have favorable effects on bone, muscle, and postural stability in a sample of independently living seniors. Thus the first aim of the project is to determine the skeletal effects of LMMS over a three year period by assessing serial quantitative computed tomography (QCT) measures of volumetric trabecular bone mineral density (vTBMB) of the hip and spine in the elderly subjects already enrolled in the original two-year study. During the trial we have developed novel methods of examining our QCT scans of the hip for muscle area and density, and have been collecting other measures not originally included in the trial, namely, muscle strength of the lower extremity, and postural stability using a balance platform. This provides data upon which the second aim is based. We hypothesize that LMMS will result in improved muscle area, density and strength, and will improve balance. The ongoing trial is well established in the senior communities, the study team has a successful track record, and there have been no safety concerns to date. Thus there is now a window of opportunity to continue the trial for an additional year and test multiple hypotheses surrounding this unique non-pharmacologic intervention. PUBLIC HEALTH RELEVANCE: The prevention of fractures in the aged population are largely focused on drug therapy to inhibit bone loss. This clinical trial of low magnitude mechanical stimulation (LMMS) in 174 elderly subjects residing in 16 retirement communities around Boston, MA (using 0.3g @ 30Hz, 10 min/d of LMMS) is intended to test a multidimensional, non-drug approach to improving the musculoskeletal system as a whole (bone, muscle, and balance). The significance of the study is that it will test the efficacy of this unique intervention to improve multiple components of the musculoskeletal system that contribute to fracture risk.