BONE LOSS AND MUSCLE WEAKNESS AT THE HIP--ELDERLY BLACK AND WHITE SUBJECTS

维生素D和钙对老年人骨密度和肌力的影响 老年女性(n=336)和男性(n=140)的髋关节将在3年内完成 1996年6月。审判中没有黑人。黑人的骨密度更高 这可能解释了他们髋部骨折发生率较低的原因，但在 髋部骨骼强度的其他组成部分，包括几何形状， 骨骼的结构和质量以及更好的肌肉力量，更低 跌倒的发生率或软组织对能量的更好吸收可能 也要参与其中。 有两个目标：I.在三岁时完成维生素D和钙质试验 研究黑人和白人在骨骼上的差异 力量、跌倒频率、软组织分布和肌肉力量 HIP并阐明导致差异的机制。要实现 第一个目标是将试验经费从1995年12月延长至6月 要求的是1997年。为了实现第二个目标，将有两个假设 测试：(1)黑人髋部骨折发生率较低的原因是：(A) 髋部的骨强度较高，这是由于较高的骨密度，但 还涉及骨骼力量的其他成分，包括骨骼 建筑、几何形状和质量；以及(B)更大的肌肉质量和 臀部的力量。(2)骨密度、建筑、几何形状和骨骼 臀部质量对预测老年黑人有独立贡献 女性和遭受髋部骨折的黑人和白人男性。 第一个假设将通过对350名黑人女性和150名黑人女性的研究来验证 60岁以上的黑人男性。将被测量的变量或 记录内容包括：骨密度、建筑、几何和质量； 矿物质动态平衡和骨转换；净钙吸收和 放射性钙吸收分数；跌倒频率和类型；肌肉 力量；臀部软组织分布。黑色中的数据将是 与已经收集的白人男性和女性的数据相比。 第二个假设将通过50名黑人的病例对照研究来检验 女性，50名黑人男性和50名白人男性髋部骨折，使用 假设(1)中的500名受试者为黑人对照组，476人 目标I中的受试者作为白色对照，并比较我们的 已发表的关于患有髋部骨折的白人女性的研究，其对照 在维生素D和钙的试验中，女性也处于基线。 这些研究将提供有关#年髋部骨折相关因素的数据 黑人，并将这些数据与从 同一区域，将允许髋部骨折的决定因素在两个 待识别的种群。

A trial of vitamin D and calcium on bone density and muscle strength at the hip in elderly women(n=336) and men(n= 140) will complete 3 years by June 1996. No blacks are in the trial. Bone density is higher in blacks which may explain their lower incidence of hip fracture but differences in other components of bone strength at the hip, including geometry, architecture and quality of bone and better muscle strength, lower incidence of falls or better absorption of the energy by soft tissues may also be involved. There are two goals: I. complete vitamin D and calcium trial at three years; II. study blacks to compare differences with whites in bone strength, fall frequency, soft tissue distribution and muscle strength at the hip and elucidate mechanisms responsible for differences. To achieve the first goal, extension of funding for the trial from Dec 1995 to June 1997 is requested. To achieve the second goal, two hypotheses will be tested: (1) the lower incidence of hip fractures in blacks is due to (a) greater bone strength at the hip which is due to higher bone density but also involves other components of bone strength, including bone architecture, geometry and quality; and (b)greater muscle mass and strength at the hip. (2) Bone density, architecture, geometry, and bone quality at the hip contribute independently, to predicting elderly black women and black and white men who have sustained a hip fracture. The first hypothesis will be tested by studying 350 black women and 150 black men over the age of 60. The variables that will be measured or recorded include: bone density, architecture, geometry and quality; mineral homeostasis and bone turnover; net calcium absorption and fractional radiocalcium absorption; frequency and type of fall; muscle strength; soft tissue distribution at the hip. The data in blacks will be compared with data already collected on white men and women. The second hypothesis will be tested by a case-control study of 50 black women, 50 black men and 50 white men who have had a hip fracture, using the 500 subjects studied in hypothesis (1) as black controls and 476 subjects in goal I. as white controls, and comparing the results in our published study of white women with hip fracture, the controls for which were also the women at base line in the trial of vitamin D and calcium. These studies will yield data on the factors related to hip fracture in blacks, and by comparing these with data already collected in whites from the same region, will allow the determinants of hip fracture in both populations to be identified.