Division of Gastroenterology, Hepatology and Nutrition, Cincinnati Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
Cancer Center, University of Hawaii, Honolulu, HI, USA.
J Clin Endocrinol Metab. 2022 Aug 18;107(9):e3887-e3900. doi: 10.1210/clinem/dgac323.
Assessment of bone health in young children has been hampered by limited reference values for bone mineral content (BMC) and areal bone mineral density (aBMD) by dual energy X-ray absorptiometry (DXA).
To identify age, sex, and population ancestry effects on BMC and aBMD and develop smoothed reference ranges for BMC and aBMD in young children. To quantify precision of bone measurements and influence of height-for-age Z-scores on bone Z-scores.
We recruited 484 healthy children ages 1 to 2 years or 4.5 to 5 years at 2 clinical centers, who were seen once or up to 7 times over a 3-year period. Lumbar spine, distal forearm, and whole-body subtotal (ages ≥ 3 years) BMC and aBMD were measured by DXA. These data were combined with data from the Bone Mineral Density in Childhood Study from children ages 5 to 8.9 years to create the smoothed reference curves.
For 1- to 5-year-olds, BMC and aBMD at all skeletal sites increased with age. Age trends differed by sex for BMC and aBMD of the spine, distal one-third radius, ultradistal radius, and by ancestry (Black vs non-Black) for all measures. BMC and aBMD precision (% coefficient of variation) ranged from 1.0% to 4.4%. Height Z-scores were positively associated with bone Z-scores and accounted for 4% to 45% of the variance.
We demonstrate the feasibility of bone density measurements in young children and provide robust reference ranges and stature adjustments for calculation of bone Z-scores at multiple skeletal sites to enable bone health assessments.
双能 X 射线吸收法（DXA）评估儿童骨健康时，由于骨矿物质含量（BMC）和面积骨矿物质密度（aBMD）的参考值有限，受到了限制。
确定年龄、性别和人群种族对 BMC 和 aBMD 的影响，制定儿童 BMC 和 aBMD 的平滑参考范围。量化骨测量的精密度以及身高年龄 Z 分数对骨 Z 分数的影响。
我们在 2 个临床中心招募了 484 名年龄在 1 至 2 岁或 4.5 至 5 岁的健康儿童，这些儿童在 3 年内接受了 1 次或多达 7 次的检查。通过 DXA 测量腰椎、远端前臂和全身总和（年龄≥3 岁）的 BMC 和 aBMD。这些数据与来自 5 至 8.9 岁儿童的儿童骨密度研究的数据相结合，创建了平滑参考曲线。
对于 1 至 5 岁的儿童，所有骨骼部位的 BMC 和 aBMD 随年龄增长而增加。BMC 和 aBMD 的年龄趋势因性别、脊柱、远端三分之一桡骨、超远端桡骨以及所有测量的种族（黑人与非黑人）而异。BMC 和 aBMD 的精密度（%变异系数）范围为 1.0%至 4.4%。身高 Z 分数与骨 Z 分数呈正相关，占变异的 4%至 45%。
我们证明了在幼儿中进行骨密度测量的可行性，并提供了多个骨骼部位的骨密度 Z 分数计算的可靠参考范围和身高调整，以实现骨健康评估。
