Fluoride and Other Factors in Childhood Bone Development

描述（由申请人提供）：尽管儿童时期骨骼发育与以后生活中骨骼健康之间的联系越来越得到证实，但关于儿童时期骨骼发育的决定因素以及它们如何导致骨质疏松症和骨折的风险，仍有许多有待了解的地方。这在一定程度上是因为相对较少的研究纵向评估了儿童时期的骨骼发育和矿物质的增加。即使是众所周知的饮食因素，如氟化物、钙和维生素D，也没有大量的儿童从出生到青春期的跟踪研究。我们当前应用的目的是将我们正在进行的纵向研究扩展到青少年。目前，我们的研究已进入第5个年头，该研究广泛调查了关键饮食因素、身体活动、候选基因多态性和亲本信息双能x射线吸收仪（DXA）、饮食、身体活动和候选基因对包括周期性DXA骨测量在内的重要终点的影响。对5岁儿童进行了骨骼和身体活动评估（n=470），对8岁儿童进行了评估（n=190）。迄今为止的分析表明，5岁的骨骼测量与身高和体重、身体活动、COL1A2和骨钙素基因多态性、氟化物、钙和维生素d呈正相关。这项更新的总体目标是在青春期的关键时期继续进行纵向评估。DXA分析（包括髋关节结构分析（HSA））和外围定量计算机断层扫描（pQCT）将用于评估11岁和13岁时的骨骼测量。将收集饮食和身体活动问卷和加速度计数据，进行额外的候选基因分析，并评估性成熟。骨骼测量将进行横断面（8岁、11岁和13岁）和纵向（5岁至13岁）分析，并与儿童的人口统计学、人体测量学、氟化物和其他饮食、身体活动、性成熟和遗传因素相关。一个重要的重点将是基因-环境相互作用效应的统计分析（例如，钙摄入量和维生素D受体基因型）以及与亲本基因型和骨骼测量的相关性。从出生开始收集纵向饮食数据的队列研究提供了一个独特的机会，揭示了儿童和青少年时期骨骼发育中可改变和不可改变因素的相对重要性，对预防骨质疏松症和骨折具有重要意义。

DESCRIPTION (provided by application): Although the link between skeletal development in childhood and bone health later in life is increasingly well established, much remains to be learned about the determinants of bone development during childhood and how they contribute to risk of osteoporosis and bone fracture. This is, in part, because relatively few studies have longitudinally assessed bone development and mineral accretion in childhood. Even for well-known dietary factors such as fluoride, calcium, and vitamin D, no large cohort of children has been followed from birth through adolescence. The objective of our current application is to extend our ongoing longitudinal study into adolescence. Currently in its 5th year, our study is a broad investigation of the effects of key dietary factors, physical activity, candidate gene polymorphisms and parental information dual-energy X-ray absorptiometry (DXA), diet, physical activity and candidate genes) on important endpoints that include periodic DXA bone measures. Age 5 bone and physical activity assessments (n=470) were conducted and age 8 assessments are in progress (n=190 so far). Analyses thus far indicate age 5 bone measures are positively associated with height and weight, physical activity, COL1A2 and osteocalcin gene polymorphisms, fluoride, calcium and vitamin D. The overall objective of this renewal is to continue longitudinal assessment through the critical years of puberty. DXA analyses (including Hip Structural Analysis (HSA)) and peripheral quantitative computed tomography (pQCT) will be used to assess bone measures at ages 11 and 13. Dietary and physical activity questionnaire and accelerometry data will be collected, additional candidate gene analyses undertaken, and sexual maturation assessed. Bone measures will be analyzed cross-sectionally (ages 8, 11, and 13) and longitudinally (ages 5 to 13), and related to children's demographic, anthropometric, fluoride and other dietary, physical activity, sexual maturity, and genetic factors. An important focus will be statistical analysis of gene-environment interaction effects (e.g., calcium intake and vitamin D receptor genotype) and correlation with parental genotypes and bone measures. Continued study of this cohort with longitudinal dietary data collected from birth provides a unique opportunity to reveal major insights into the relative importance of modifiable and non-modifiable factors on bone development during childhood and adolescence, with implications for prevention of osteoporosis and bone fractures.