TY - JOUR
T1 - Vitamin C supplementation for pregnant smoking women and pulmonary function in their newborn infants
T2 - A randomized clinical trial
AU - McEvoy, Cindy T.
AU - Schilling, Diane
AU - Clay, Nakia
AU - Jackson, Keith
AU - Go, Mitzi D.
AU - Spitale, Patricia
AU - Bunten, Carol
AU - Leiva, Maria
AU - Gonzales, David
AU - Hollister-Smith, Julie
AU - Durand, Manuel
AU - Frei, Balz
AU - Buist, A. Sonia
AU - Peters, Dawn
AU - Morris, Cynthia D.
AU - Spindel, Eliot R.
PY - 2014/5/28
Y1 - 2014/5/28
N2 - IMPORTANCE: Maternal smoking during pregnancy adversely affects offspring lung development, with lifelong decreases in pulmonary function and increased asthma risk. In a primate model, vitamin C blocked some of the in-utero effects of nicotine on lung development and offspring pulmonary function. OBJECTIVE: To determine if newborns of pregnant smokers randomized to receive daily vitamin C would have improved results of pulmonary function tests (PFTs) and decreased wheezing compared with those randomized to placebo. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind trial conducted in 3 sites in the Pacific Northwest between March 2007 and January 2011. One hundred fifty-nine newborns of randomized pregnant smokers (76 vitamin C treated and 83 placebo treated) and 76 newborns of pregnant nonsmokers were studied with newborn PFTs. Follow-up assessment including wheezing was assessed through age 1 year, and PFTs were performed at age 1 year. INTERVENTIONS: Pregnant women were randomized to receive vitamin C (500 mg/d) (n = 89) or placebo (n = 90). MAIN OUTCOMES AND MEASURES: The primary outcomewas measurement of newborn pulmonary function (ratio of the time to peak tidal expiratory flow to expiratory time [TPTEF:TE] and passive respiratory compliance per kilogram [Crs/kg]) within 72 hours of age. Secondary outcomes included incidence of wheezing through age 1 year and PFT results at age 1 year. A subgroup of pregnant smokers and nonsmokers had genotyping performed. RESULTS: Newborns of women randomized to vitamin C (n = 76), compared with those randomized to placebo (n = 83), had improved pulmonary function as measured by TPTEF:TE (0.383 vs 0.345 [adjusted 95% CI for difference, 0.011-0.062]; P = .006) and Crs/kg (1.32 vs 1.20 mL/cm H 2O/kg [95% CI, 0.02-0.20]; P = .01). Offspring of women randomized to vitamin C had significantly decreased wheezing through age 1 year (15/70 [21%] vs 31/77 [40%]; relative risk, 0.56 [95% CI, 0.33-0.95]; P = .03). There were no significant differences in the 1-year PFT results between the vitamin C and placebo groups. The effect of maternal smoking on newborn lung function was associated with maternal genotype for the α5 nicotinic receptor (rs16969968) (P < .001 for interaction). CONCLUSIONS AND RELEVANCE: Supplemental vitamin C taken by pregnant smokers improved newborn PFT results and decreased wheezing through 1 year in the offspring. Vitamin C in pregnant smokers may be an inexpensive and simple approach to decrease the effects of smoking in pregnancy on newborn pulmonary function and respiratory morbidities. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00632476
AB - IMPORTANCE: Maternal smoking during pregnancy adversely affects offspring lung development, with lifelong decreases in pulmonary function and increased asthma risk. In a primate model, vitamin C blocked some of the in-utero effects of nicotine on lung development and offspring pulmonary function. OBJECTIVE: To determine if newborns of pregnant smokers randomized to receive daily vitamin C would have improved results of pulmonary function tests (PFTs) and decreased wheezing compared with those randomized to placebo. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind trial conducted in 3 sites in the Pacific Northwest between March 2007 and January 2011. One hundred fifty-nine newborns of randomized pregnant smokers (76 vitamin C treated and 83 placebo treated) and 76 newborns of pregnant nonsmokers were studied with newborn PFTs. Follow-up assessment including wheezing was assessed through age 1 year, and PFTs were performed at age 1 year. INTERVENTIONS: Pregnant women were randomized to receive vitamin C (500 mg/d) (n = 89) or placebo (n = 90). MAIN OUTCOMES AND MEASURES: The primary outcomewas measurement of newborn pulmonary function (ratio of the time to peak tidal expiratory flow to expiratory time [TPTEF:TE] and passive respiratory compliance per kilogram [Crs/kg]) within 72 hours of age. Secondary outcomes included incidence of wheezing through age 1 year and PFT results at age 1 year. A subgroup of pregnant smokers and nonsmokers had genotyping performed. RESULTS: Newborns of women randomized to vitamin C (n = 76), compared with those randomized to placebo (n = 83), had improved pulmonary function as measured by TPTEF:TE (0.383 vs 0.345 [adjusted 95% CI for difference, 0.011-0.062]; P = .006) and Crs/kg (1.32 vs 1.20 mL/cm H 2O/kg [95% CI, 0.02-0.20]; P = .01). Offspring of women randomized to vitamin C had significantly decreased wheezing through age 1 year (15/70 [21%] vs 31/77 [40%]; relative risk, 0.56 [95% CI, 0.33-0.95]; P = .03). There were no significant differences in the 1-year PFT results between the vitamin C and placebo groups. The effect of maternal smoking on newborn lung function was associated with maternal genotype for the α5 nicotinic receptor (rs16969968) (P < .001 for interaction). CONCLUSIONS AND RELEVANCE: Supplemental vitamin C taken by pregnant smokers improved newborn PFT results and decreased wheezing through 1 year in the offspring. Vitamin C in pregnant smokers may be an inexpensive and simple approach to decrease the effects of smoking in pregnancy on newborn pulmonary function and respiratory morbidities. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00632476
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U2 - 10.1001/jama.2014.5217
DO - 10.1001/jama.2014.5217
M3 - Article
C2 - 24838476
AN - SCOPUS:84901640278
SN - 0098-7484
VL - 311
SP - 2074
EP - 2082
JO - JAMA
JF - JAMA
IS - 20
ER -