Maternal Vitamin C Supplementation to Decrease Effects of Smoking During Pregnancy on Infant Lung Function and Health: Follow-up of 2 Randomized Trials and Association With Changes in DNA Methylation
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 395
- 试验地点
- 2
- 主要终点
- Improved pulmonary function
研究概览
简要总结
In a randomized clinical trial (RCT) published in JAMA, the investigators have provided evidence that vitamin C supplementation (500 mg daily during pregnancy) ameliorates the effects of maternal smoking during pregnancy on offspring lung function and subsequent incidence of wheeze by 48% through 1 year of age. The investigators are currently completing a second RCT of vitamin C supplementation in pregnant smokers with more robust measures of pulmonary outcomes. The purpose of this ECHO application is to combine these 2 focused, interventional cohorts to allow critical longitudinal follow-up of respiratory outcomes in these children including the study of pulmonary function test (PFT) trajectories and incidence of recurrent wheeze/asthma from infancy through early adolescence in offspring of pregnant smokers randomized to vitamin C versus placebo.
详细描述
In a randomized clinical trial (RCT) published in JAMA, the investigators have provided evidence that vitamin C supplementation (500 mg daily during pregnancy) ameliorates the effects of maternal smoking during pregnancy on offspring lung function and subsequent incidence of wheeze by 48% through 1 year of age. the investigators are currently completing a second RCT of vitamin C supplementation in pregnant smokers with more robust measures of pulmonary outcomes. The purpose of this ECHO application is to combine these 2 focused, interventional cohorts to allow critical longitudinal follow-up of respiratory outcomes in these children including the study of pulmonary function test (PFT) trajectories and incidence of recurrent wheeze/asthma from infancy through early adolescence in offspring of pregnant smokers randomized to vitamin C versus placebo.
This will allow the investigators to study the duration of the protection vitamin C provides in the face of in-utero smoke, the relationship between PFTs and the development of recurrent wheeze and/or asthma. In addition we have preliminary data suggesting that, in parallel with the effects of vitamin C on the reduction of pulmonary harm, the supplementary vitamin C blocked the majority of significant changes in DNA methylation induced by maternal smoking in placentas, cord blood and offspring cheek cells. Thus this study will also study the association between the prevention of wheeze/asthma associated with maternal smoking during pregnancy and the prevention of epigenetic changes caused by maternal smoking during pregnancy. By linking the clinical outcomes of decreased wheeze/asthma and pulmonary function in offspring of smokers to epigenetic changes, this study has the potential to identify genes linked to the effects of maternal smoking on lung development and the protective effects of vitamin C.
研究设计
- 研究类型
- Observational
- 观察模型
- Case Control
- 时间视角
- Prospective
入排标准
- 年龄范围
- 6 Months 至 11 Years（Child）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Women and their offspring randomized to vitamin C versus placebo during pregnancy in VCSIP1 or VCSIP2 as well as pregnant nonsmokers and their offspring enrolled as the reference group in VCSIP 1 or VCSIP2
排除标准
- •Patients specifically withdrawing consent from VCSIP1 or VCSIP2
结局指标
主要结局
Improved pulmonary function
时间窗: through 15 years of age
The first primary aim of this study is to demonstrate improved pulmonary function trajectories as measured with forced expiratory flows through 15 years of age in the offspring of pregnant smokers randomized to vitamin C (500 mg/day) versus placebo.
Decreased recurrent wheeze/asthma
时间窗: through 15 years of age
The second primary aim of this study is to demonstrate a decreased incidence of recurrent wheeze/ asthma through 15 years of age in the offspring of pregnant smokers randomized to vitamin C (500 mg/day) versus placebo.
次要结局
- Epigenetic changes(through 15 years of age)
- Decreased incidence of recurrent wheeze/asthma(through 15 years of age)
研究者
Cynthia McEvoy
MD, MCR
Oregon Health and Science University