Division of General and Community Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
J Bone Miner Res. 2013 Jan;28(1):206-12. doi: 10.1002/jbmr.1730.
Little is known about factors that affect bone mass and density of infants and toddlers and the means to assess their bone health owing to challenges in studying this population. The objectives of this study were to describe age, sex, race, growth, and human milk feeding effects on bone mineral content (BMC) and areal density (aBMD) of the lumbar spine, and determine precision of BMC and aBMD measurements. We conducted a cross-sectional study of 307 healthy participants (63 black), ages 1 to 36 months. BMC and aBMD of the lumbar spine were measured by dual-energy X-ray absorptiometry. Duplicate scans were obtained on 76 participants for precision determination. Age-specific Z-scores for aBMD, weight, and length (BMDZ, WAZ, LAZ) were calculated. Information on human milk feeding duration was ascertained by questionnaire. Between ages 1 and 36 months, lumbar spine BMC increased about fivefold and aBMD increased twofold (p < 0.0001). BMC was greater (5.8%) in males than in females (p = 0.001), but there was no difference in aBMD (p = 0.37). There was no difference in BMC or aBMD between whites and blacks (p ≥ 0.16). WAZ and LAZ were positively associated with BMDZ (r = 0.34 and 0.24, p < 0.001). Duration of human milk feeding was negatively associated with BMDZ in infants <12 months of age (r = -0.42, p < 0.001). Precision of BMC and aBMD measurements was good, 2.20% and 1.84%, respectively. Dramatic increases in BMC and aBMD of the lumbar spine occur in the first 36 months of life. We provide age-specific values for aBMD of healthy infants and toddlers that can be used to evaluate bone deficits. Future studies are needed to identify the age when sex and race differences in aBMD occur, and how best to account for delayed or accelerated growth in the context of bone health assessment of infants and toddlers.
目前对于影响婴幼儿骨量和骨密度的因素以及评估其骨骼健康的方法知之甚少，这主要是因为研究这一人群存在诸多挑战。本研究的目的是描述年龄、性别、种族、生长和人乳喂养对腰椎骨矿物质含量 (BMC) 和面积密度 (aBMD) 的影响，并确定 BMC 和 aBMD 测量的精密度。我们对 307 名健康参与者（63 名黑人）进行了横断面研究，年龄为 1 至 36 个月。通过双能 X 射线吸收法测量腰椎 BMC 和 aBMD。对 76 名参与者进行了重复扫描以确定精密度。计算了特定年龄的 aBMD、体重和长度的 Z 分数 (BMDZ、WAZ、LAZ)。通过问卷确定了人乳喂养持续时间的信息。在 1 至 36 个月期间，腰椎 BMC 增加了约五倍，aBMD 增加了两倍（p<0.0001）。男性的 BMC （5.8%）高于女性（p=0.001），但 aBMD 无差异（p=0.37）。白人和黑人之间的 BMC 或 aBMD 无差异（p≥0.16）。WAZ 和 LAZ 与 BMDZ 呈正相关（r=0.34 和 0.24，p<0.001）。12 个月以下婴儿的人乳喂养时间与 BMDZ 呈负相关（r=-0.42，p<0.001）。BMC 和 aBMD 测量的精密度良好，分别为 2.20%和 1.84%。在生命的头 36 个月内，腰椎 BMC 和 aBMD 急剧增加。我们提供了健康婴儿和幼儿特定年龄的 aBMD 值，可用于评估骨量不足。需要进一步研究以确定 aBMD 性别和种族差异出现的年龄，以及如何在评估婴儿和幼儿骨骼健康时最好地考虑生长延迟或加速。
