Epidemiologic Study of Bone Marrow Fat and Osteoporosis

描述（由申请人提供）：与女性相比，对老年男性骨质疏松症和骨质疏松性骨折的病因和预防知之甚少。尽管骨质疏松症相关研究取得了实质性进展，但骨质疏松症的病理生理学仍不完全清楚。最近的研究表明，一种新的因素，骨髓脂肪（BMF），作为一个潜在的原因或结果，与年龄相关的骨质疏松症，由于观察到较高的BMF在骨质疏松症的受试者和其潜在的关系与成骨细胞和脂肪细胞的生成。随着非侵入性骨髓评估技术的出现，对BMF和骨骼健康之间关系的更广泛研究已成为可能。据我们所知，只有少数研究直接研究了BMF和骨矿物质密度（BMD）之间的联系，这些研究主要集中在中国男性和女性身上。BMF在骨质疏松症中的作用的许多方面仍然是未知的。首先，尚不清楚在中国人群中观察到的BMF和区域BMD之间的负相关是否也可以推广到美国人群。此外，传统的区域BMD评估仅提供骨强度的部分信息。BMF是否与真实的体积BMD、骨强度和骨形成/吸收调节相关需要进一步研究。本申请旨在通过招募150名目前正在匹兹堡临床试验机构参与男性骨质疏松性骨折（MrOS）研究的男性，提高我们对BMF与骨密度、几何结构和骨转换之间关系的理解。将使用最先进的磁共振光谱技术定量椎体BMF。将采用双能X线吸收测定法（DXA）和外周定量断层扫描（pQCT）测量骨密度（面积和体积）、大小和强度。此外，还将提供骨转换标志物和生活方式、医学和人体测量特征数据库，以评估BMF与骨骼健康之间的联系。这项拟议的研究将为研究界提供对骨质疏松症病因的新认识，特别是在老年男性中。它还为预防和/或治疗高危人群的骨质疏松症和骨质疏松性骨折开辟了新的机会。

DESCRIPTION (provided by applicant): Compared with women, much less is known about the etiology and prevention of osteoporosis and osteoporotic fractures in older men. Despite the substantial progress in osteoporosis-related research, the pathophysiology of osteoporosis remains incompletely understood. Recent studies have suggested a novel factor, bone marrow fat (BMF), as a potential cause or consequence of age-related osteoporosis due to the observation of higher BMF in osteoporotic subjects and its underlying relationship with osteoblast and adipocyte genesis. Broader study of the relationships between BMF and skeletal health has become feasible recently with the availability of non-invasive techniques for assessing bone marrow. To our knowledge, only a handful of studies have directly examined the connection between BMF and bone mineral density (BMD), and these studies have largely focused on Chinese men and women. Many aspects of the role of BMF on osteoporosis remain largely unknown. First, it is not clear whether the inverse association between BMF and areal BMD observed in the Chinese population can also be generalized to US populations. In addition, the conventional areal BMD assessment only provides partial information on bone strength. Whether or not BMF is associated with true volumetric BMD, bone strength, and bone formation/resorption regulation requires further investigation. The current application seeks to improve our understanding of the connection of BMF with bone density, geometry and turnover by recruiting 150 men who are currently participating in the Osteoporotic Fractures in Men (MrOS) study at the Pittsburgh clinic site. Vertebral BMF will be quantified using the-state-of-the-art Magnetic Resonance Spectroscopy technique. Dual energy x-ray absorptiometry (DXA) and peripheral quantitative tomography (pQCT) will be employed to obtain measures of bone density (areal and volumetric), size and strength. In addition, bone turnover markers and a database of lifestyle, medical and anthropometric characteristics will also be available to evaluate the link between BMF and skeletal health. This proposed study will provide the research community with novel understanding toward the etiology of osteoporosis, especially in older men. It also opens a new opportunity for prevention and/or treatment of osteoporosis and osteoporotic fractures among at-risk populations.