Respiratory illness contributed significantly to morbidity in children born extremely premature or with extremely low birthweights in 1999–2000

AIM: This study investigated respiratory morbidity and risk factors during the first five years of life after extremely preterm birth. METHODS: Paediatric assessments and parental questionnaires were obtained at two and five years of age in this national prospective cohort of 372 Norwegian children born during 1999-2000 at a gestational age of <28 weeks or birthweight <1,000 grams. RESULTS: Paediatric assessments were obtained for 100% and 82% of the children at two and five years of age and completed questionnaires for 71% and 76%, respectively. Total readmission rates decreased from 49 to 14% at one to five years, and readmissions for respiratory causes fell from 31 to 3%. Bronchopulmonary dysplasia (BPD) or gestational age was not associated with readmissions for respiratory causes in multiple logistic regression models. However, both BPD and gestational age ≤ 25 weeks was associated with wheezing during the first year and the use of asthma medication during the first two years. BPD was associated with asthma medication between three and five years but not significantly at five years. CONCLUSION: Respiratory morbidity decreased during the first five years of life but was still more common than expected. It was unrelated to BPD and gestational age at five years of age.