Vitamin C to pregnant smokers persistently improves infant airway function to 12 months of age: a randomised trial

Abstract

<jats:sec><jats:title>Background</jats:title><jats:p>Vitamin C (500 mg·day<jats:sup>−1</jats:sup>) supplementation for pregnant smokers has been reported to increase newborn pulmonary function and infant forced expiratory flows (FEFs) at 3 months of age. Its effect on airway function through 12 months of age has not been reported.</jats:p></jats:sec><jats:sec><jats:title>Objective</jats:title><jats:p>To assess whether vitamin C supplementation to pregnant smokers is associated with a sustained increased airway function in their infants through 12 months of age.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>This is a prespecified secondary outcome of a randomised, double-blind, placebo-controlled trial that randomised 251 pregnant smokers between 13 and 23 weeks of gestation: 125 to 500 mg·day<jats:sup>−1</jats:sup> vitamin C and 126 to placebo. Smoking cessation counselling was provided. FEFs performed at 3 and 12 months of age were analysed by repeated measures analysis of covariance.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>FEFs were performed in 222 infants at 3 months and 202 infants at 12 months of age. The infants allocated to vitamin C had significantly increased FEFs over the first year of life compared to those allocated to placebo. The overall increased flows were: 40.2 mL·sec<jats:sup>−1</jats:sup> for FEF<jats:sub>75</jats:sub> (adjusted 95% CI for difference 6.6 to 73.8; p=0.025); 58.3 mL·sec<jats:sup>−1</jats:sup> for FEF<jats:sub>50</jats:sub> (95% CI 10.9 to 105.8; p=0.0081); and 55.1 mL·sec<jats:sup>−1</jats:sup> for FEF<jats:sub>25–75</jats:sub> (95% CI, 9.7 to 100.5; p=0.013).</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>In offspring of pregnant smokers randomised to vitamin C <jats:italic>versus</jats:italic> placebo, vitamin C during pregnancy was associated with a small but significantly increased airway function at 3 and 12 months of age, suggesting a potential shift to a higher airway function trajectory curve. Continued follow-up is underway.</jats:p></jats:sec>

Trajectories of Lung Function in Infants and Children: Setting a Course for Lifelong Lung Health

“…Two separate randomized trials have shown that vitamin C supplementation to pregnant women unable to quit smoking improved the lung function of their offspring through 12 months of age. 32,33,68 Interventions to decrease in utero smoke exposure or mitigate its effects will likely improve airway function trajectories in both preterm and term infants particularly with the increased use of electroniccigarettes. 69 In the postnatal period, a randomized trial of premature infants has revealed that extending treatment with CPAP until 34 weeks PMA significantly increased lung volumes as measured by FRC at discharge, 27 a finding that suggests one postnatal pathway to improve lung trajectories.…”

Strategies for Prevention or Treatment of Tobacco and Cannabis Use Disorder

“…A second larger RCT randomized 251 pregnant women between 13 and 23 weeks gestation who smoked to either placebo or 500 mg oral vitamin C daily. 51 Infants in the vitamin C group were found to have improved forced expiratory flows over the first year. Continued follow-up on these populations are ongoing.…”

Nutritional problems in smokers and passive smokers

“…Algunos estudios han señalado que mejorar la situación de la vitamina C en las gestantes fumadoras puede ayudar a antagonizar el daño inducido por la nicotina. Concretamente, en un ensayo aleatorizado y controlado con placebo, al suministrar vitamina C a mujeres embarazadas fumadoras se observó una mejora, estadísticamente significativa, de la función pulmonar del descendiente a los 3 meses (24) y 12 meses de edad (25).…”