Channing Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
J Allergy Clin Immunol. 2012 Jul;130(1):53-60.e4. doi: 10.1016/j.jaci.2012.04.005. Epub 2012 May 16.
The adverse effects of corticosteroids on bone mineral accretion (BMA) have been well documented. Vitamin D insufficiency, a prevalent condition in the pediatric population, has also been associated with decreased bone mineral density (BMD).
We sought to determine whether children with asthma who have lower vitamin D levels are more susceptible to the negative effects of corticosteroids on BMD over time.
Children aged 5 to 12 years with mild-to-moderate asthma who participated in the Childhood Asthma Management Program were followed for a mean of 4.3 years. Total doses of inhaled corticosteroids and oral corticosteroids (OCSs) were recorded, serum 25-hydroxyvitamin D3 levels were measured at the beginning of the trial, and serial dual-energy x-ray absorptiometry scans of the lumbar spine were performed. Annual BMA rates were defined as follows: [(BMD at 4 years' follow-up - BMD at baseline)/4 years].
BMA was calculated for 780 subjects. In boys baseline vitamin D levels significantly modified the relationship between OCSs and BMA (vitamin D × OCS interaction, P= .023). Stratification by vitamin D levels showed a decrease in BMA with increased use of OCSs in vitamin D-insufficient boys only (P< .001). Compared with vitamin D-sufficient boys, vitamin D-insufficient boys exposed to more than 2 courses of OCSs per year had twice the decrease in BMA rate (relative to boys who were OCS unexposed).
Vitamin D levels significantly modified the effect of OCSs on BMA in boys. Further research is needed to examine whether vitamin D supplementation in children with poorly controlled asthma might confer benefits to bone health.
皮质类固醇对骨矿物质积累（BMA）的不良影响已有充分的记载。维生素 D 不足，儿科人群中的一种常见情况，也与骨密度（BMD）降低有关。
我们试图确定患有哮喘的儿童，如果维生素 D 水平较低，是否更容易随着时间的推移受到皮质类固醇对 BMD 的负面影响。
参加儿童哮喘管理计划的 5 至 12 岁轻度至中度哮喘儿童平均随访 4.3 年。记录吸入皮质类固醇和口服皮质类固醇（OCS）的总剂量，在试验开始时测量血清 25-羟维生素 D3 水平，并对腰椎进行连续双能 X 线吸收法扫描。每年 BMA 率定义为：[（4 年随访时的 BMD-基线时的 BMD）/4 年]。
共计算了 780 名患者的 BMA。在男孩中，基线维生素 D 水平显著改变了 OCS 与 BMA 之间的关系（维生素 D×OCS 相互作用，P=.023）。根据维生素 D 水平分层显示，维生素 D 不足的男孩中，随着 OCS 使用量的增加，BMA 减少（维生素 D 不足的男孩 P<.001）。与维生素 D 充足的男孩相比，暴露于每年超过 2 个 OCS 疗程的维生素 D 不足的男孩 BMA 率下降了两倍（与未暴露于 OCS 的男孩相比）。
维生素 D 水平显著改变了 OCS 对男孩 BMA 的影响。需要进一步研究，以检验在控制不佳的哮喘儿童中补充维生素 D 是否对骨骼健康有益。
