The EPICure Study: Association between Hemodynamics and Lung Function at 11 Years after Extremely Preterm Birth

Charlotte E Bolton,Janet Stocks,Enid Hennessy,John R Cockcroft,Joseph Fawke,Sooky Lum,Carmel M Mceniery,Ian B Wilkinson,Neil Marlow

doi:10.1016/j.jpeds.2012.03.052

Abstract

ObjectiveTo investigate the relationship between disturbed lung function and large-artery hemodynamics in school-age children born extremely preterm (EP) (at 25 completed weeks of gestation or less).Study designThis was a cross-sectional study of participants from the EPICure study, now aged 11 years (n = 66), and 86 age- and sex-matched term-born classmates. Spirometry parameters (including forced expiratory volume in 1 second), blood pressure, and augmentation index (AIx, a composite of arterial stiffness and global wave reflections) were measured.ResultsCompared with their classmates, the EP children had significantly impaired lung function, particularly those with neonatal bronchopulmonary dysplasia. Peripheral blood pressure did not differ significantly between the 2 groups, but AIx values were on average 5% higher (95% CI, 2%-8%) in the preterm infants, remaining significant after adjustment for potential confounders. Neonatal bronchopulmonary dysplasia status was not related to AIx. Lung function and maternal smoking were independently associated with AIx; AIx increased by 2.7% per z-score reduction in baseline forced expiratory volume in 1 second and by 4.9% in those whose mothers smoked during pregnancy.ConclusionThe independent association between impaired lung function and cardiovascular physiology in early adolescence implies higher cardiovascular risk for children born EP, and suggests that prevention of chronic neonatal lung disease may be a priority in reducing later cardiovascular risk in preterm infants.

Highlights

Alongside a number of traditional risk factors, disturbed lung function has emerged as a key independent risk factor for cardiovascular disease in adults.[1,2]
Impaired lung function has repeatedly been demonstrated in children born very preterm, independent of chronic neonatal lung disease or bronchopulmonary dysplasia (BPD).[8]
The implications of preterm birth are of increasing relevance to adult physicians, given improved survival,[12] tracking of lung function throughout life,[13,14,15] and concerns that the normal age-related decline in lung function may be accelerated in such individuals.[16]

Summary

Methods

EPICure is a population-based study of all births between March and December 1995 in the United Kingdom and Republic of Ireland, born at 25 completed weeks of gestation or less (the data-sharing policy is available from www.epicure. ac.uk). EPICure is a population-based study of all births between March and December 1995 in the United Kingdom and Republic of Ireland, born at 25 completed weeks of gestation or less Details of the cohort ascertainment and progress have been reported elsewhere.[19,20] The current investigation was part of an extensive assessment of this cohort at age 11 years comprising neurocognitive, respiratory, and other outcomes.[29,30,31,32,33] Measurements were performed in school by 1 of 3 specially trained pediatricians. Schools were asked to identify up to 3 classmates as potential comparisons, matched for age, sex, and ethnic origin, 1 of whom was selected at random.[29,30] Classmates were excluded if born at

Results

Discussion

Conclusion