Navajo Bone Health Study

描述(由申请人提供)：纳瓦霍人骨健康研究旨在开始对纳瓦霍人的骨健康进行监测。这些努力将使纳瓦霍民族能够及时规划针对骨折或骨质疏松症风险最大的人群的筛查和文化上适当的教育和干预方案。具体地说，我们假设纳瓦霍美洲印第安人的骨密度(总骨密度，以及髋部和腰椎的骨密度)将不同于高加索人。我们将通过使用双能X射线骨密度仪(DXA)和跟部超声(宽带超声衰减(BUA)、声速(SOS)以及僵硬指数(SI))测量骨密度(BMD)来验证这一假设，并将其与NHANES III数据库中按年龄和性别分组报告的高加索人的分布和z分数进行比较。我们的目标是验证脚跟超声在纳瓦霍印第安人骨健康筛查中的应用，并为这一人群的转诊建立临床相关的临界值。我们将检查已报道的成人骨折与骨密度测量(DXA和BUA)的关系，以将这些联系起来 有关公共卫生结果的措施。此外，我们还将研究身体大小、饮食(与骨形成相关的营养素，包括钙、维生素D、维生素A和蛋白质)和生活方式(体力活动)因素与18岁以上纳瓦霍成年人和儿童骨密度的关系。数据收集将采用与纳瓦霍地球队列研究一致的横断面设计。将对随机选择的1296名纳瓦霍男女进行DXA测量。我们将在四个10岁年龄组(30-39岁、40-49岁、50-59岁和60岁及以上)选择112名男性和112名女性，以确保我们可以分别充分估计每个性别特定年龄组的骨密度。将对大约2500名纳瓦霍男女进行脚后跟超声测量，并使用DXA测量骨密度，报告成人骨折，并探讨饮食和生活方式因素。这项研究是监测纳瓦霍美洲印第安人骨骼健康的重要第一步，并有效地利用了目前在该领域的纳瓦霍地球队列研究。

DESCRIPTION (provided by applicant): The Navajo Bone Health Study aims to begin surveillance of bone health on the Navajo Nation. These efforts will in time enable the Navajo Nation to plan screening and culturally appropriate education and intervention programs targeted towards the segments of the population who are at greatest risk for fracture or osteoporosis. Specifically, we hypothesize that bone density (total bone mineral density (BMD), and BMD at the hip and lumbar spine) will be different in Navajo American Indians than Caucasians. We will examine this hypothesis by measuring bone mineral density (BMD) using dual energy x-ray absorptiometry (DXA) and heel ultrasound (broadband ultrasound attenuation (BUA) and speed of sound (SOS) as well as stiffness index (SI)) compare distributions and z-scores with those reported for Caucasians in the NHANES III database by age and gender groups. We aim to validate the use of heel ultrasound for bone health screening in Navajo Native Americans and create clinically relevant cutoffs for referral in this population. We will examine the association of reported adult fractures with BMD measures (DXA and BUA) to relate these measures to a relevant public health outcomes. In addition we will examine the association of body size, diet (nutrients relevant to bone formation including calcium, vitamin D, Vitamin A and protein), and lifestyle (physical activity) factors to and BMD in Navajo adults and children over the age of 18. Data will be collected in a cross-sectional design coincident with the Navajo EARTH cohort study. DXA will be measured in 1296 randomly selected Navajo men and women. We will select 112 men and 112 women in four 10 year age groups (30-39,40-49,50-59, and 60 and older) to assure that we can adequately estimate BMD in each of these gender specific age groups separately. Heel ultrasound will be measured in approximately 2500 Navajo men and women and associations with BMD measured using DXA, reported adult fractures, and diet and lifestyle factors will be explored. This study is an important first step in surveillance of bone health of Navajo American Indians and make efficient use of the Navajo EARTH Cohort Study which is currently in the field.