Bone Turnover and Fracture Risk in Men

描述(申请人提供)：尽管人们对男性骨质疏松症越来越感兴趣，但关于男性骨折的发病机制和危险因素，或在这一人群中有效的诊断策略的数据很少。为了解决这些问题，正在进行的男性骨质疏松症研究(MROS)成功地从6个美国临床中心招募了6000多名65岁以上的男性。MRO收集了广泛的人体测量和健康习惯的基线测量，以及轴向密度测量和腰椎侧位X线片。髋部和脊柱的基线QCT以及性激素已经被分成几个子集进行了测量。自基线访问以来，一直跟踪受试者是否发生新的骨折，截至2005年2月，已报告46例髋部骨折和总共256例非脊柱骨折并进行了中央判定。研究参与者将从2005年1月开始返回临床中心进行重复的脊柱X光和密度测量，平均随访时间为4.5年。在这项MROS辅助研究中，我们计划使用基线的存档血清和尿样，并采用有效的嵌套病例队列研究设计，对骨转换与脊柱、髋部和任何非脊柱骨折之间的关系进行前瞻性分析。我们的抽样计划将利用MRO中现有的许多测量方法，包括DXA、QCT和性激素水平。此外，我们将分析一种新的非侵入性骨胶原质量生化指标-1型胶原异构化与脊柱、髋部和任何非脊柱骨折的发生之间的关系。在老年女性中的前瞻性研究表明，骨转换和胶原蛋白异构化都与骨折风险独立相关，但这种关系尚未在男性中进行研究。最后，我们计划研究骨转换和骨丢失，并确定哪些人体测量、历史和健康习惯因素与骨转换有关。这些分析将解决有关男性脊柱和非脊柱骨折发病机制的关键问题，并将确定骨转换测量在这一人群中的临床应用。

DESCRIPTION (provided by applicant): Despite growing interest about osteoporosis in men, there is little data regarding the pathogenesis and risk factors for fracture in men, or effective diagnostic strategies in this population. To address these issues, the ongoing Osteoporosis in Men Study (MrOS) has successfully recruited over 6000 men over age 65 from 6 US clinical centers. MrOS collected extensive baseline measurements of anthropometric and health habits, as well as axial densitometry and lateral lumbosacral spine radiographs. Baseline QCT of the hip and spine, and sex hormones have been measured in subsets. Since the baseline visit, subjects have been followed for the occurrence of new fractures, and as of February 2005, 46 hip fractures and a total of 256 non-spine fractures have been reported and centrally adjudicated. Study participants will return to the clinical centers for repeat spine x-rays and densitometry beginning January, 2005, after a mean follow-up of 4.5 years. In this MrOS ancillary study, we plan to use archived serum and urine specimens from baseline and propose a prospective analysis of the relationship between bone turnover and incident vertebral, hip and any non-spine fracture using an efficient nested case-cohort study design. Our sampling scheme will take advantage of the many existing measurements in MrOS, including DXA, QCT and sex hormone levels. In addition, we will analyze the relationship between a new non-invasive biochemical index of bone collagen quality, type 1 collagen isomerization, and incident vertebral, hip and any non-spine fracture. Propective studies among older women suggest that both bone turnover and collage isomerization are independently associated with fracture risk, but such relationships have not been studied in men. Lastly, we plan to study bone turnover and bone loss, and determine which anthropometric, historical and health habit factors are associated with bone turnover. These analyses will address critical questions about the pathogenesis of spine and non-spine fracture in men, and will determine the clinical utility of bone turnover measurements in this population.