Effect of IUGR and catch-up growth on later lung function in preterm children: prospective cohort study

Abstract

<b>Introduction:</b> Preterm children with intrauterine growth restriction (IUGR) have deficits in lung function compared to those without but the effects of catch-up growth are unclear. <b>Aims and objectives:</b> We investigated if preterm children born with IUGR have lower lung function at 7-12 years of age compared to preterm children without IUGR and term children; and if catch-up growth results in higher spirometry measures compared to children without IUGR. <b>Methods:</b> 544 preterms born at ≤34 weeks’ gestation (468 without IUGR; and 76 with IUGR from which 63 had catch-up growth) and 195 term children had respiratory symptoms assessed, FeNO measured and had spirometry before/after a bronchodilator in our Respiratory Health Outcomes in Neonates (RHiNO) study. Comparisons were adjusted for potential confounders using general linear models. <b>Results:</b> Preterm children with IUGR had deficits in lung function compared to the preterm group without IUGR but these differences decreased after bronchodilators. The preterm children with IUGR who had catch-up growth had higher spirometry measurements compared to the preterm children with IUGR who did not show catch-up growth but the measures remained lower than the preterm children without IUGR. These differences were in general reduced after bronchodilators. <b>Conclusions:</b> Preterm-born children with IUGR have deficits in lung function compared to preterm-born children without IUGR and term-born children. The IUGR group showing catch-up growth had higher lung function results compared to the IUGR preterm group without catch-up growth but remained lower than the preterm group without IUGR.