Bone microarchitecture, diabetes and change in bone mineral density in Puerto Rican adults

项目摘要 最近的国家数据表明，与非西班牙裔相比，西班牙裔骨质疏松症（OP）的患病率更高。 西班牙裔白人或黑人。作为美国人口中增长最快的群体之一，这一群体是 预计从2005年到2025年，OP相关骨折的增幅最大。加勒比海西班牙裔成年人 西班牙裔白人的骨质比非西班牙裔白人差。尤其是波多黎各人， OP的患病率高于以前的估计。虽然较高的骨矿物质密度（BMD） 在2型糖尿病（T2D）患者中，T2D导致骨强度受损，皮质骨 骨缺损和增加的皮质孔隙度增加骨折的风险。这是波多黎各特别关切的问题 2型糖尿病患病率高的波多黎各人。T2D患者骨质差的一种机制是 晚期糖基化终产物（AGE）的积累，影响骨的力学性能。动物 研究表明，维生素B6的抗氧化活性可以抑制AGE的形成。血浆吡哆醇浓度升高- 5'-磷酸盐（PLP，维生素B6）浓度和维生素B6的摄入量与骨质减少有关 随着时间的推移，骨折的风险降低;但机制尚不清楚。小梁骨评分（TBS），一种新的 腰椎骨小梁微结构的测量，是脆性骨折风险的指示，即使在 骨密度正常者;然而，关于TBS评估骨质量的研究有限且迫切需要。 此外，通过新的微压痕评估骨强度可以阐明骨质量的差异 因此，我们的中心假设是，波多黎各成年T2D患者将有 骨强度差（微压痕），脊柱TBS和脊柱和髋关节BMD损失更大 与没有T2D的个体相比;并且这将被高血浆AGE浓度所缓和。我们 次要假设是血浆PLP越高，血浆AGE越低， 更高的骨强度（微压痕），以及随着时间推移TBS和BMD的损失更少。全部可用860 Puerto 参加波士顿波多黎各骨质疏松研究并具有有效BMD数据的波多黎各成年人将 邀请参加拟议的研究。参与者将完成一份问卷，重复DXA扫描， 接受骨微压痕、皮肤自体荧光AGES测定并提供空腹血 sample.拟议的研究是创新的，包括TBS作为衡量骨质量，微观， 压痕来评估骨强度，检查AGE作为连接糖尿病和骨的效应修饰剂 健康，以及在纵向研究中将PLP作为年龄因素的考虑。这项工作迫切需要 提高我们对骨骼健康复杂风险因素的理解，并为研究提供重要信息。 制定未来的干预措施，以预防骨质流失和骨折风险，特别是在高危人群中 健康差距。

PROJECT SUMMARY Recent national data indicate a higher prevalence of osteoporosis (OP) among Hispanics, compared with non- Hispanic whites or blacks. As one of the fastest growing segments of the U.S. population, this group is projected to have the largest increase in OP-related fracture from 2005 to 2025. Hispanic adults of Caribbean origin have been shown to have poorer bone quality than non-Hispanic whites. Puerto Ricans, in particular, have higher prevalence of OP than previously appreciated. Although higher bone mineral density (BMD) has been noted in those with type 2 diabetes (T2D), T2D contributes to compromised bone strength, cortical defects and increased cortical porosity increasing risk of fracture. This is of particular concern for Puerto Ricans who have a high prevalence of T2D. One mechanism for poor bone quality among those with T2D is the accumulation of advanced glycation end-products (AGE), which affect bone mechanical properties. Animal studies suggest that antioxidant activity from vitamin B6 may inhibit AGE formation. Greater plasma pyridoxyl- 5'-phosphate (PLP, vitamin B6) concentration and intake of vitamin B6 has been associated with less bone loss over time and reduced risk of fracture; but mechanisms are unclear. Trabecular bone score (TBS), a novel measure of trabecular microarchitecture of the lumbar spine, is indicative of fragility fracture risk, even among those with normal BMD; however, research on TBS for assessing bone quality is limited and urgently needed. Further, assessment of bone strength by novel micro-indentation may elucidate differences in bone quality among T2D at risk for OP. Therefore, our central hypothesis is that Puerto Rican adults with T2D will have poor bone strength (micro-indentation), and greater loss of TBS at the spine and of BMD at the spine and hip compared to individuals without T2D; and that this will be moderated by high plasma AGE concentration. Our secondary hypothesis is that greater plasma PLP will be associated with lower plasma AGE and therefore higher bone strength (micro-indentation), and less loss of TBS and BMD over time. All available 860 Puerto Rican adults who participated in the Boston Puerto Rican Osteoporosis Study with valid BMD data will be invited to participate in the proposed study. Participants will complete a questionnaire, a repeat DXA scan, undergo bone micro-indentation, skin autofluorescence measurement of AGES and provide a fasting blood sample. The proposed research is innovative in the inclusion of TBS as a measure of bone quality, micro- indentation to evaluate bone strength, the examination of AGE as an effect modifier linking diabetes and bone health, and the consideration of PLP as a factor in AGE in a longitudinal study. This work is urgently needed to improve our understanding of complex risk factors for bone health, and to provide important information for the development of future interventions to prevent bone loss and fracture risk, particularly in high-risk populations with health disparities.