Abstract
Background: Prematurity is a risk factor for viral bronchiolitis but few studies have analyzed hospitalization rates in very preterm infants without bronchopulmonary dysplasia (BPD).
Aims and objectives: 1) To determine the hospitalization rates for acute viral bronchiolitis in very preterm infants (≤ 32 weeks gestational age, wGA) without BPD as compared to matched full-term infants during their first winter season and 2) to identify risk factors for hospitalization.
Methods: Observational prospective multicenter study, conducted during the 2008-2009 winter epidemic in 9 French regions. Infants were matched (1:1) for date of birth, gender and birth location.
Results: 498 infants (249 preterms, mean GA: 31.4±0.9 weeks and 249 full-terms) were included. Mean age of infants at enrollment was 2.8±1.6 months. Forty infants (35 preterms and 5 full-terms) were hospitalized for bronchiolitis, out of which 20 were RSV-positive (16 preterms and 4 full-terms). The hospitalization rates for overall bronchiolitis were 14.1% in the preterm group versus 2.0% in the full-term group (RR: 7.00, 95%CI: 2.79-17.57; p < 0.0001). The hospitalization rates for RSV bronchiolitis were 6.4% in the preterm group versus 1.6% in the full-term group (RR: 4.00, 95%CI: 1.36-11.80; p = 0.006). The number of hospitalizations increased significantly with male gender and the presence of siblings of ≥ 2 years of age at home.
Conclusion: Very preterm infants without BPD have a 7 and 4 fold increased risk of hospitalization for overall and RSV bronchiolitis respectively, as compared to full term infants. Male gender and siblings ≥ 2 years of age are additional risk factors for overall bronchiolitis hospitalizations.
- © 2011 ERS