VITAMIN D SUPPLEMENTATION IN POSTMENOPAUSAL BLACK WOMEN

骨质疏松症是世界范围内的一个重大公共卫生问题。 尽管黑人女性被认为患乳腺癌的风险较低， 骨折比白色妇女，骨折的风险在绝经后 黑人女性仍然很多。黑人的25岁以下 羟维生素D水平和甲状旁腺激素升高 与白色女性相比。这些研究结果是一致 维生素D缺乏症，或在某些情况下，真正缺乏。维生素D 在白色人群中，随着年龄的增长， 女性人口。此外，在白色老年妇女和男子中， 维生素D治疗导致骨丢失率降低， 骨折补充维生素D的效果从来没有 在黑人女性中进行评估。我们假设 相对25（OH）D不足，存在于黑人 绝经后妇女可能会加剧衰老过程中的骨质流失 黑人女性为了验证这一假设，我们建议进行一次 随机临床试验比较维生素D补充（1000 IU/天）与安慰剂在一项为期两年的研究中， 黑人绝经后（>5岁）妇女， 25（OH）D不足。我们建议确定是否补充 维生素D（1000 IU）改善矿物质代谢，增加钙 吸收，减少骨转换，降低骨丢失率， 黑人绝经后妇女 此外，我们打算确定 维生素D对人体的生物化学和骨密度的影响 黑人妇女的补充与等位基因变异有关， 维生素D受体黑人女性骨折的频率较低 比白色妇女和往往有更高的骨量， 从骨质疏松症治疗研究中排除了该种族群体， 预防然而，黑人女性的骨折率仍然是 相当可观一种简单安全的营养补充剂， 维生素D可以降低骨质流失率和骨质疏松症的风险， 黑人女性骨折

Osteoporosis is a major public health problem throughout the world. Although black women are believed to be at lower risk of osteoporotic fracture than white women, the risk of fracture in postmenopausal black women is still substantial. Blacks have consistently lower 25- hydroxy-vitamin D levels and an elevation in parathyroid hormone level compared to white women. These findings are consistent with vitamin D insufficiency, or in some, true deficiency. Vitamin D insufficiency has been implicated in bone loss with aging in the white female population. furthermore, in white elderly women and men, treatment with vitamin D has resulted in a lower rate of bone loss and fractures. The effect of vitamin D supplementation has never been evaluated in black women. We hypothesize that the presence of relative 25(OH)D insufficiency that exists among black postmenopausal women may exacerbate loss of bone among aging black women. To test this hypothesis, we propose to conduct a randomized clinical trial to compare vitamin D supplementation (1000 IU/ day) with placebo during a two year study in a population of 150 black postmenopausal (>5 years) women, who are shown to be 25(OH)D insufficient. We propose to determine whether supplemental vitamin D (1000 IU) improves mineral metabolism, increases calcium absorption, reduces bone turnover and reduces the rate of bone loss in black postmenopausal women. In addition, we intend to determine whether biochemical and bone density responses to vitamin D supplementation in black women are related to allelic variation in the vitamin D receptor. The fact that black women fracture less frequently than white woman and tend to have higher bone mass has virtually excluded this ethnic group from studies of osteoporosis treatment and prevention. However, the fracture rate in black women is still substantial. It is possible that a simple, safe nutritional supplement, vitamin D, could reduce the rate of bone loss and risk of osteoporotic fracture in black women.