LONG TERM FLUORIDE EXPOSURE AND FRACTURES IN CHINA

氟与骨骼强度和骨折之间的关系是 不太了解。 最近的生态研究表明， 氟化水供应可能与增加 髋关节骨折的频率，但这样的研究有相当大的潜力 在评估氟化物暴露时的错误。 很少有美国人只消费 一次饮用水，终生饮用;此外， 自2005年以来，氟化物只被添加到美国的供水中。 20世纪40年代，广泛的氟化作用在20世纪60年代才变得普遍。 最 这些研究中的美国人只是在1998年后期才接触到氟化物。 生活 然而，这些研究以及最近的信息， 使用氟化钠的治疗试验已经提出了一种可能性， 氟暴露可能会增加骨折风险（不包括椎骨）。 骨折）。 为了解决这个问题，我们提出了一个研究氟化物暴露 长期稳定暴露于氟化物的人群中的骨折。 在中国农村，人口流动性很小， 相应地，很少接触到来自家庭以外的氟化物 村 我们建议：1）在50-60个村庄确定7,500名中国人， 明确定义的长期暴露于一系列浓度的氟化物 括号l ppm，美国用于氟化的“最佳”水平， 社区供水; 2）评估（并通过X光和医疗检查确认 记录）这些受试者的成人骨折史，并确定 村级骨折患病率与长期患病率的关系 长期氟暴露; 3）测量钙摄入量、体力活动 （主要是劳动力），以及与两者潜在相关的其他因素 氟暴露和骨折

The relationship between fluoride and skeletal strength and fractures is poorly understood. Recent ecologic studies have suggested that exposure to fluoridated water supplies may be associated with an increased frequency of hip fractures, but such studies have considerable potential for error in assessing fluoride exposure. Few Americans consume only beverages from a single water supply for their lifetime; additionally, fluoride has only been added to water supplies in the U.S. since the late 1940s, and widespread fluoridation only became common in the 1960s. Most Americans included in these studies were only exposed to fluoride late in life. However, these studies together with recent information from therapeutic trials using sodium fluoride have raised the possibility that fluoride exposure may increase fracture risk (excluding vertebral fractures). To address this issue we propose a study of fluoride exposure and fractures in a population with long-term stable exposures to fluoride. In rural China there is very little population mobility, and correspondingly little exposure to fluoride from sources outside the home village. We propose to: l) identify 7,500 Chinese in 50-60 villages with well-defined, long-term exposures to fluoride in a range of concentrations bracketing l ppm, the 'optimal' level used in the U.S. for fluoridation of community water supplies; 2) assess (and confirm with x-rays and medical records) the adult fracture histories of these subjects, and determine the relationship between fracture prevalence at the village level and long- term fluoride exposure; 3) measure calcium intake, physical activity (primarily labor), and other factors potentially associated with both fluoride exposure and fractures.