Vitamin C to Decrease Effects of Smoking in Pregnancy on Infant Lung Function (VCSIP)
Pulmonary Function; Newborn, Abnormal
Second Hand Smoke
Dietary Supplement: Vitamin C +prenatal vitamin
Dietary Supplement: Placebo tablet+prenatal vitamin
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Care Provider, Investigator, Outcomes Assessor)
|Official Title:||Vitamin C to Decrease Effects of Smoking in Pregnancy on Infant Lung Function|
- Pulmonary function testing at 3 months of age in infants born to smoking pregnant women randomized to daily vitamin C versus placebo. The measurement of forced expiratory flow at 75% of expired volume (FEF75)will be compared between the groups. [ Time Frame: 3 months of age ]FEF75 will be measured when the infant is 3 months of age using the raised volume rapid thoracic compression pulmonary function testing technique
- Incidence of wheezing through 12 months of age in infants born to pregnant smoking women randomized to vitamin C versus placebo during pregnancy. [ Time Frame: 12 months of age ]The incidence of wheezing through 12 months of age will be compared in the infants delivered to smoking pregnant women who were randomized to vitamin C (500 mg) versus placebo during pregnancy.
- Pulmonary function testing at 12 months of age in infants born to smoking pregnant women randomized to daily vitamin C versus placebo. The measurement of forced expiratory flow at 75% of expired volume (FEF75)will be compared between the groups. [ Time Frame: 12 months of age ]The measurement of forced expiratory flows and specifically FEF75 will be done at 12 months of age in infants born to pregnant smoking women randomized to vitamin C versus placebo during pregnancy. FEF75 will be measured with the raised volume rapid thoracic compression technique.
|Study Start Date:||December 2012|
|Estimated Study Completion Date:||November 2016|
|Primary Completion Date:||April 2016 (Final data collection date for primary outcome measure)|
Placebo Comparator: placebo tablet+prenatal vitamin
A daily placebo tablet
|Dietary Supplement: Placebo tablet+prenatal vitamin|
|Active Comparator: Vitamin C +prenatal vitamin||
Dietary Supplement: Vitamin C +prenatal vitamin
Pregnant smoking women will be randomized to daily vitamin C (500 mg) versus daily placebo
Other Name: Ascorbic acid
Smoking during pregnancy remains a major public health problem as at least 12% of pregnant women cannot quit smoking during pregnancy. This addiction is the largest preventable cause of childhood respiratory illness, including asthma, and children whose mothers smoked during pregnancy show lifetime decreases in pulmonary function. Smoking is a unique morbidity in that it is addictive, heavily advertised and recent genome studies show there are genotypes that significantly increase the likelihood of being unable to quit. Teen pregnancy, low income, low education, and living with another smoker are important factors increasing the odds of smoking during pregnancy. Pulmonary function tests done shortly after birth in babies born to mothers who smoked during pregnancy show decreased pulmonary function as measured by decreased respiratory flows and respiratory compliance and altered tidal breathing patterns. These changes can still be measured even after the infants have reached adulthood. Multiple epidemiologic studies show that these decreases in pulmonary function lead to increased respiratory disease and costs of hundreds of millions of dollars per year.
The primary aim of this double-blind, placebo controlled, randomized, multi-site study is to demonstrate improved pulmonary function testing at 3 months of age, in infants delivered to smoking mothers who are randomized to 500 mg/day of supplemental vitamin C versus placebo at less than or equal to 22 weeks of pregnancy. We will recruit 278 smoking pregnant women into the study. Patients will meet with research personnel at each prenatal visit and smoking cessation will be actively encouraged. Patients will be monitored with a set of serial biomarkers to assess smoking and medication compliance, including urine cotinine levels, smoking questionnaires, pill counts and fasting plasma ascorbic acid levels. Pulmonary function tests will be done at 3 months of age and will measure forced expiratory flows. The infants will also be followed through one year of age with monthly validated respiratory questionnaires and a follow-up pulmonary function test at 12 months of age. Success of this study is supported by strong pilot data showing statistically significant improvements at about 48 hours of age in pulmonary function tests in infants born to smoking mothers who received vitamin C versus placebo, and preliminary data showing a lower incidence of wheezing at 12 months of age in these infants. Key genetic polymorphisms shown to increase sensitivity to in-utero smoke exposure will also be measured. The success of this study is also supported by animal models showing the effectiveness of vitamin C to preserve pulmonary function and genetic and epidemiologic studies linking the effects of smoking during pregnancy to oxidant mechanisms. The secondary aims of the study include: 1) to demonstrate a decreased incidence of wheezing through 12 months of age in infants delivered to smoking mothers who are randomized to 500mg/day of supplemental vitamin C versus placebo during pregnancy; 2) to demonstrate improved pulmonary function tests at 12 months of age in these infants.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01723696
|United States, Indiana|
|Indianapolis, Indiana, United States, 46202-5167|
|United States, Oregon|
|Oregon Health & Science University|
|Portland, Oregon, United States, 97239|
|Principal Investigator:||Cynthia T McEvoy, MD,MCR||Oregon Health and Science University|