Ganmaa Davaasambuu, Stuart Jennifer J, Sumberzul Nyamjav, Ninjin Boldbaatar, Giovannucci Edward, Kleinman Ken, Holick Michael F, Willett Walter C, Frazier Lindsay A, Rich-Edwards Janet W
Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States of America.
Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, United States of America.
PLoS One. 2017 May 8;12(5):e0175237. doi: 10.1371/journal.pone.0175237. eCollection 2017.
Symptomatic vitamin D deficiency is associated with slowed growth in children. It is unknown whether vitamin D repletion in children with asymptomatic serum vitamin D deficiency can restore normal growth.
We tested the impact of vitamin D-supplementation on serum concentrations of 25-hydroxyvitamin D [25(OH)D] and short-term growth in Mongol children, with very low serum vitamin D levels in winter.
We conducted two randomized, double-blind, placebo-controlled trials in urban school age children without clinical signs of rickets. The Supplementation Study was a 6-month intervention with an 800 IU vitamin D3 supplement daily, compared with placebo, in 113 children aged 12-15 years. A second study, the Fortification Study, was a 7-week intervention with 710 ml of whole milk fortified with 300 IU vitamin D3 daily, compared with unfortified milk, in 235 children aged 9-11 years.
At winter baseline, children had low vitamin D levels, with a mean (±SD) serum 25-hydroxyvitamin D [25(OH)D] concentration of 7.3 (±3.9) ng/ml in the Supplementation Study and 7.5 (±3.8) ng/ml in the Fortification Study. The serum levels increased in both vitamin D groups-by 19.8 (±5.1) ng/ml in the Supplementation Study, and 19.7 (±6.1) ng/ml in the Fortification Study. Multivariable analysis showed a 0.9 (±0.3 SE) cm greater increase in height in the vitamin-D treated children, compared to placebo treated children, in the 6-month Supplementation Study (p = 0.003). Although the children in the 7-week Fortification Study intervention arm grew 0.2 (±0.1) cm more, on average, than placebo children this difference was not statistically significant (p = 0.2). There were no significant effects of vitamin D supplements on differences in changes in weight or body mass index in either trial. For the Fortification Study, girls gained more weight than boys while taking vitamin D 3 (p-value for interaction = 0.03), but sex was not an effect modifier of the relationship between vitamin D3 and change in either height or BMI in either trial.
Correcting vitamin D deficiency in children with very low serum vitamin D levels using 800 IU of vitamin D3 daily for six months increased growth, at least in the short-term, whereas, in a shorter trial of 300 IU of D fortified milk daily for 7 weeks did not.
有症状的维生素D缺乏与儿童生长缓慢有关。无症状血清维生素D缺乏的儿童补充维生素D是否能恢复正常生长尚不清楚。
我们测试了补充维生素D对蒙古族儿童血清25-羟基维生素D[25(OH)D]浓度和短期生长的影响，这些儿童在冬季血清维生素D水平极低。
我们在无佝偻病临床体征的城市学龄儿童中进行了两项随机、双盲、安慰剂对照试验。补充研究是一项为期6个月的干预，113名12至15岁的儿童每天补充800 IU维生素D3，与安慰剂组进行比较。第二项研究，强化研究，是一项为期7周的干预，235名9至11岁的儿童每天饮用710毫升添加300 IU维生素D3的全脂牛奶，与未强化牛奶组进行比较。
在冬季基线时，儿童维生素D水平较低，补充研究中血清25-羟基维生素D[25(OH)D]浓度的均值（±标准差）为7.3（±3.9）ng/ml，强化研究中为7.5（±3.8）ng/ml。两个维生素D组的血清水平均有所升高——补充研究中升高了19.8（±5.1）ng/ml，强化研究中升高了19.7（±6.1）ng/ml。多变量分析显示，在为期6个月的补充研究中，与安慰剂治疗的儿童相比，接受维生素D治疗的儿童身高增加了0.9（±0.3标准误）厘米（p = 0.003）。虽然在为期7周的强化研究中干预组的儿童平均比安慰剂组的儿童多生长了0.2（±0.1）厘米，但这一差异无统计学意义（p = 0.2）。在两项试验中，维生素D补充剂对体重或体重指数变化的差异均无显著影响。对于强化研究，女孩在服用维生素D3时比男孩体重增加更多（交互作用的p值 = 0.03），但在两项试验中，性别均不是维生素D3与身高或体重指数变化之间关系的效应修饰因素。
对于血清维生素D水平极低的儿童，每天使用800 IU维生素D3纠正维生素D缺乏持续6个月至少在短期内可促进生长，而在一项为期7周、每天饮用添加300 IU维生素D的强化牛奶的较短试验中则未起到促进生长的作用。
