Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Mass; COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark.
Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Mass.
J Allergy Clin Immunol. 2017 Nov;140(5):1423-1429.e5. doi: 10.1016/j.jaci.2017.01.013. Epub 2017 Mar 9.
Nutrient trials differ from drug trials because participants have varying circulating levels at entry into the trial.
We sought to study the effect of a vitamin D intervention in pregnancy between subjects of different races and the association between 25-hydroxyvitamin D (25[OH]D) levels in pregnancy and the risk of asthma/recurrent wheeze in offspring.
The Vitamin D Antenatal Asthma Reduction Trial is a randomized trial of pregnant women at risk of having children with asthma randomized to 4400 international units/d vitamin D or placebo plus 400 international units/d vitamin D. Asthma and recurrent wheezing until age 3 years were recorded.
African American (AA) women (n = 312) had lower initial levels of 25(OH)D (mean [SD], 17.6 ng/mL [8.3 ng/mL]) compared with non-AA women (n = 400; 27.1 ng/mL [9.7 ng/mL], P < .001). No racial difference was found from vitamin D supplementation in pregnancy on asthma/recurrent wheezing in offspring (P for interaction = .77). Having an initial level of greater than 30 ng/mL and being randomized to the intervention group was associated with the lowest risk for asthma/recurrent wheeze by age 3 years compared with having an initial level of less than 20 ng/mL and receiving placebo (adjusted odds ratio, 0.42; 95% CI, 0.19-0.91).
We did not find differences between AA and non-AA mothers in the effect of maternal vitamin D supplementation and asthma/recurrent wheeze in offspring at 3 years. Maternal supplementation of vitamin D, particularly in mothers with initial 25(OH)D levels of greater than 30 ng/mL, reduced asthma/recurrent wheeze in the offspring through age 3 years, suggesting that higher vitamin D status beginning in early pregnancy is necessary for asthma/recurrent wheeze prevention in early life.
营养素试验与药物试验不同，因为参与者在进入试验时的循环水平不同。
我们旨在研究不同种族的孕妇接受维生素 D 干预的效果，以及孕妇体内 25-羟维生素 D（25[OH]D）水平与后代患哮喘/反复喘息的风险之间的关系。
维生素 D 产前哮喘减少试验是一项针对有患哮喘风险的孕妇的随机试验，将其随机分为每天 4400 国际单位维生素 D 或安慰剂加每天 400 国际单位维生素 D 组。记录哮喘和 3 岁前反复喘息的情况。
与非非裔美国人（AA）女性（n=400）相比，非非裔美国人（AA）女性（n=312）的初始 25（OH）D 水平（平均值[标准差]，17.6ng/mL[8.3ng/mL]）较低（P<0.001）。在怀孕期间补充维生素 D 对后代的哮喘/反复喘息没有发现种族差异（P 交互作用值=0.77）。与初始水平低于 20ng/mL 并接受安慰剂相比，初始水平大于 30ng/mL 且随机分配到干预组的孕妇在 3 岁时发生哮喘/反复喘息的风险最低（调整后的优势比，0.42；95%置信区间，0.19-0.91）。
我们没有发现 AA 母亲和非 AA 母亲之间在母亲维生素 D 补充和 3 岁时后代哮喘/反复喘息的效果上存在差异。母亲补充维生素 D，特别是在初始 25（OH）D 水平大于 30ng/mL 的母亲中，通过 3 岁降低了后代的哮喘/反复喘息，这表明在妊娠早期开始就具有较高的维生素 D 状态对于预防生命早期的哮喘/反复喘息是必要的。
