Jepsen Karl J, Kozminski Andrew, Bigelow Erin Mr, Schlecht Stephen H, Goulet Robert W, Harlow Sioban D, Cauley Jane A, Karvonen-Gutierrez Carrie
Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, MI, USA.
Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA.
J Bone Miner Res. 2017 Jun;32(6):1218-1228. doi: 10.1002/jbmr.3082. Epub 2017 Jan 30.
The impact of adult bone traits on changes in bone structure and mass during aging is not well understood. Having shown that intracortical remodeling correlates with external size of adult long bones led us to hypothesize that age-related changes in bone traits also depend on external bone size. We analyzed hip dual-energy X-ray absorptiometry images acquired longitudinally over 14 years for 198 midlife women transitioning through menopause. The 14-year change in bone mineral content (BMC, R = 0.03, p = 0.015) and bone area (R = 0.13, p = 0.001), but not areal bone mineral density (aBMD, R = 0.00, p = 0.931) correlated negatively with baseline femoral neck external size, adjusted for body size using the residuals from a linear regression between baseline bone area and height. The dependence of the 14-year changes in BMC and bone area on baseline bone area remained significant after adjusting for race/ethnicity, postmenopausal hormone use, the 14-year change in weight, and baseline aBMD, weight, height, and age. Women were sorted into tertiles using the baseline bone area-height residuals. The 14-year change in BMC (p = 0.009) and bone area (p = 0.001) but not aBMD (p = 0.788) differed across the tertiles. This suggested that women showed similar changes in aBMD for different structural and biological reasons: women with narrow femoral necks showed smaller changes in BMC but greater increases in bone area compared to women with wide femoral necks who showed greater losses in BMC but without large compensatory increases in bone area. This finding is opposite to expectations that periosteal expansion acts to mechanically offset bone loss. Thus, changes in femoral neck structure and mass during menopause vary widely among women and are predicted by baseline external bone size but not aBMD. How these different structural and mass changes affect individual strength-decline trajectories remains to be determined. © 2017 American Society for Bone and Mineral Research.
成人骨骼特征对衰老过程中骨骼结构和质量变化的影响尚未得到充分理解。已有研究表明，皮质内重塑与成人长骨的外部尺寸相关，这使我们推测与年龄相关的骨骼特征变化也取决于骨骼外部尺寸。我们分析了198名处于绝经过渡期的中年女性在14年期间纵向采集的髋部双能X线吸收测定图像。经使用基线骨面积与身高之间线性回归的残差对体型进行校正后，骨矿物质含量（BMC，R = 0.03，p = 0.015）和骨面积（R = 0.13，p = 0.001）的14年变化与基线股骨颈外部尺寸呈负相关，但面骨矿物质密度（aBMD，R = 0.00，p = 0.931）与基线股骨颈外部尺寸无相关性。在校正种族/族裔、绝经后激素使用情况、体重的14年变化以及基线aBMD、体重、身高和年龄后，BMC和骨面积的14年变化对基线骨面积的依赖性仍然显著。根据基线骨面积 - 身高残差将女性分为三个三分位数组。三分位数组之间BMC（p = 0.009）和骨面积（p = 0.001）的14年变化存在差异，但aBMD（p = 0.788）无差异。这表明，由于不同的结构和生物学原因，女性在aBMD方面表现出相似的变化：与股骨颈宽的女性相比，股骨颈窄的女性BMC变化较小，但骨面积增加幅度更大，而股骨颈宽的女性BMC损失更大，但骨面积没有相应的大幅代偿性增加。这一发现与骨膜扩张可机械性抵消骨质流失的预期相反。因此，绝经期间股骨颈结构和质量的变化在女性中差异很大，且可由基线骨骼外部尺寸而非aBMD预测。这些不同的结构和质量变化如何影响个体的力量下降轨迹仍有待确定。© 2017美国骨与矿物质研究学会。
