Center for Child Health Care Studies, Department of Population Medicine, Harvard Pilgrim Health Care Institute and Harvard Medical School, Boston, MA 02215-5301, USA.
Am J Respir Crit Care Med. 2012 Sep 15;186(6):508-13. doi: 10.1164/rccm.201202-0351OC. Epub 2012 Jul 12.
Low vitamin D levels are associated with asthma and decreased airway responsiveness. Treatment with inhaled corticosteroids improves airway responsiveness and asthma control.
To assess the effect of vitamin D levels on prebronchodilator FEV(1), bronchodilator response, and responsiveness to methacholine (PC(20), provocative concentration of methacholine producing a 20% decline in FEV(1)) in patients with asthma treated with inhaled corticosteroids.
We measured 25-hydroxyvitamin D levels in the serum of children with persistent asthma at the time of enrollment in the Childhood Asthma Management Program. We divided subjects into the vitamin D sufficiency (>30 ng/ml), insufficiency (20-30 ng/ml), and deficiency (<20 ng/ml) groups. Covariates included age, treatment, sex, body mass index, race, history of emergency department visits, hospitalizations, and season that vitamin D specimen was drawn. Our main outcome measures were change in prebronchodilator FEV(1), bronchodilator response, and PC(20) from enrollment to 8-12 months.
Of the 1,024 subjects, 663 (65%) were vitamin D sufficient, 260 (25%) were insufficient, and 101 (10%) were deficient. Vitamin D-deficient subjects were more likely to be older, African American, and have a higher body mass index compared with the vitamin D-sufficient and insufficient subjects. In the inhaled corticosteroid treatment group, prebronchodilator FEV(1) increased from randomization to 12 months by 140 ml in the vitamin D-deficient group and prebronchodilator FEV(1) increased by 330 ml in the vitamin D insufficiency group and by 290 ml in the vitamin D sufficiency group (P = 0.0072), in adjusted models.
In children with asthma treated with inhaled corticosteroids, vitamin D deficiency is associated with poorer lung function than in children with vitamin D insufficiency or sufficiency.
维生素 D 水平较低与哮喘和气道反应性降低有关。吸入皮质类固醇治疗可改善气道反应性和哮喘控制。
评估维生素 D 水平对接受吸入皮质类固醇治疗的哮喘患者的支气管扩张剂前 FEV1、支气管扩张剂反应以及对乙酰甲胆碱（PC20，引起 FEV1 下降 20%的乙酰甲胆碱激发浓度）的反应的影响。
我们在儿童哮喘管理计划入组时测量了持续性哮喘儿童血清中的 25-羟维生素 D 水平。我们将受试者分为维生素 D 充足（>30ng/ml）、不足（20-30ng/ml）和缺乏（<20ng/ml）组。协变量包括年龄、治疗、性别、体重指数、种族、急诊就诊史、住院史和抽取维生素 D 标本的季节。我们的主要观察指标是从入组到 8-12 个月时支气管扩张剂前 FEV1、支气管扩张剂反应和 PC20 的变化。
在 1024 名受试者中，663 名（65%）为维生素 D 充足，260 名（25%）为不足，101 名（10%）为缺乏。与维生素 D 充足和不足的受试者相比，维生素 D 缺乏的受试者年龄更大、为非裔美国人且体重指数更高。在吸入皮质类固醇治疗组中，维生素 D 缺乏组支气管扩张剂前 FEV1 从随机分组到 12 个月时增加了 140ml，维生素 D 不足组增加了 330ml，维生素 D 充足组增加了 290ml（P=0.0072），在调整后的模型中。
在接受吸入皮质类固醇治疗的哮喘儿童中，维生素 D 缺乏与维生素 D 不足或充足的儿童相比，肺功能更差。
