Respiratory health in pre-school and school age children following extremely preterm birth

Abstract

Rationale: Increasing survival at extremely low gestational ages is associated with very high rates of bronchopulmonary dysplasia (BPD) but is rarely quantified.

Objectives: To identify respiratory morbidity and risk factors in the EPICure cohort over the first 6 years of life.

Methods: 308 babies born at < or =25 weeks' gestation in 1995 were followed up at 30 months and 6 years of age. Respiratory outcome was evaluated using clinical assessment, parental questionnaire and peak expiratory flow (PEF) at 6 years.

Results: 74% of this population received supplemental oxygen at 36 weeks postmenstrual age and 36% were discharged with supplemental oxygen which continued for a median of 2.5 months (75th percentile: 8.5 months). 236 children were followed to 6 years. Respiratory symptoms and medication use were more prevalent at 30 months and 6 years in children with BPD compared to those without. Children without BPD (n = 56) were not significantly different from their classmates but had consistently higher prevalence of poor respiratory health. Symptoms, need for hospital admission and medication use declined between 30 months and 6 years. 200 index children completed three PEF measures; PEF was lower than in classmates (mean adjusted difference: 39 l/min (95% CI 30 to 47)) and was lowest in children discharged home with oxygen and in those with BPD. Gestational age, BPD and maternal smoking at home and in pregnancy were independent risk factors for symptoms, but BPD was the only independent associate of PEF.

Conclusion: Extremely preterm children have a continuum of poor respiratory health over the first 6 years, which is exacerbated by smoking during pregnancy and in the home.