Causes and Consequences of Hyperkyphosis in Older Women

描述(申请人提供)：脊柱后凸过弯是指胸椎过度弯曲，俗称“唐氏驼峰”。它在老年人群中经常被观察到，但对其原因或后果知之甚少。虽然之前的一些小规模研究表明，骨质疏松只占后凸畸形的不到一半，但人们普遍认为，后凸畸形主要是由脊椎骨折引起的，但尚未得到证实。后凸畸形的其他潜在原因包括遗传易感性、退行性腰椎间盘疾病和肌肉无力。后凸过长与不良后果相关，包括肺功能受限、身体功能差以及死亡风险增加，而这并不是脊椎骨折的原因。这些先前的研究表明，后凸过缓是健康状况不佳的重要临床指标。然而，目前还没有确定的临床标准来定义什么程度的后凸角度构成了过度后凸。因此，界定后凸畸形并确定其原因和后果对老年患者的健康具有重要意义。 为了定义后凸畸形，了解其发病机制并了解其健康后果，我们建议使用现有的综合性数据集--骨质疏松性骨折研究(SOF)--进行一系列分析。SOF是美国第一项也是最大规模的前瞻性研究，主要致力于老年女性骨质疏松性骨折的研究。自1986年以来，参与者参加了一系列关于骨折和其他慢性病风险因素的检查。在这项研究中，我们建议根据现有的基线X线片和基线后平均3.5年和15年重复拍摄的X线片来测量后凸角度。我们创建了一个数字化程序，可以计算最广泛使用的脊柱后凸放射学测量--柯布角。因此，可以以最小的努力在大量的受试者中进行可靠的测量。利用SOF的现有数据，我们将：1)量化1000名老年女性的后凸角度，确定多少后凸畸形是由潜在的骨质疏松症引起的，以及多少与其他潜在的风险因素有关，这些因素包括遗传倾向、肌肉无力、椎间盘高度丧失和健康行为；2)通过与跌倒、骨折和功能限制等重要结果的关联，确定脊柱后凸Uc角构成多大程度的后凸畸形。这是首次对后凸畸形的原因和后果进行全面研究。这种对现有数据集的具有成本效益和创新性的使用很可能产生对这一共同情况的第一次系统分析。

DESCRIPTION (provided by applicant): Hyperkyphosis refers to an excessive curvature of the thoracic spine, commonly known as the "Dowagers hump." It is frequently observed in the older population, and yet little is known about its causes or consequences. It is generally assumed, but not proven, that hyperkyphosis primarily results from vertebral fractures, although previous small studies suggest that osteoporosis only accounts for less than half of hyperkyphosis. Potential other causes of hyperkyphosis include a genetic predisposition, degenerative disc disease, and muscular weakness. Hyperkyphosis is associated with adverse outcomes including restricted pulmonary function, poor physical function, and an increased risk of mortality that is not accounted for by vertebral fractures. These previous studies suggest that hyperkyphosis is an important clinical indicator of poor health. However, there are no set clinical criteria that define what degree of kyphotic angle constitutes hyperkyphosis. Therefore, defining hyperkyphosis and determining its causes and consequences has important implications for the health of older patients. To define hyperkyphosis, understand its pathogenesis and learn its health outcomes, we propose to conduct a series of analyses using an existing comprehensive data set, the Study of Osteoporotic Fractures (SOF). SOF is the first and largest prospective U.S. study devoted primarily to the study of osteoporotic fractures in older women. Since 1986, participants have attended serial exams of risk factors for fractures and other chronic diseases. In this study, we propose to measure the kyphotic angle from existing baseline radiographs and from repeated radiographs taken an average of 3.5 and 15 years after baseline. We created a digitization program that calculates the most widely used radiological measure of kyphosis, the Cobb angle. Thus, a reliable measure can be made in a large number of subjects with minimal effort. Using existing data from SOF, we will: 1) quantify the kyphotic angle in 1000 older women and determine how much of hyperkyphosis is due to underlying osteoporosis and how much is related to other potential risk factors including a genetic predisposition, muscle weakness, intervertebral disc height loss, and health behaviors; and 2) define what degree of kyphoUc angle constitutes hyperkyphosis by its association with important outcomes including falls, fractures, and functional limitations. This is the first comprehensive study of the causes and consequences of hyperkyphosis. This cost-effective and innovative use of an existing data set is likely to produce the first systematic analyses of this common condition.