Rehospitalisations for respiratory disease and respiratory syncytial virus infection in preterm infants of 29-36 weeks gestational age

BACKGROUND: To evaluate rates of rehospitalisation due to respiratory illness in preterm infants of 29-36 weeks gestation without chronic lung disease. PATIENTS AND METHODS: Retrospective single centre cohort study including infants from 1998 to 1999 with follow-up over two respiratory syncytial virus (RSV) seasons. RESULTS: Of 435 infants included 61 infants (14%) experienced 78 rehospitalisations. The overall RSV attack rate was 4.4% over two consecutive RSV seasons for infants below 6 months of age at onset of RSV season (7.7 and 1.1%, respectively, p=0.015), with significant differences between infants of 29-32 and 33-36 weeks gestational age (10.5% vs. 2.3%, p=0.008). None of the infants needed mechanical ventilation or admission to the intensive care unit. Infants with RSV infection were younger of age (mean 4.2 vs. 8.2 months; p=0.015), had longer stays at the hospital (11.5 vs. 7.0 days; p=0.006), and more severe courses of disease (score 3.0 vs. 1.8; p<0.001). Additional risk factors for RSV infection were multiple gestation (OR 5.5; CI 95% 1.439-21.028) and congenital heart disease (OR 4.2; CI 95% 1.005-17.669). CONCLUSION: The total burden of respiratory disease and RSV infection in this population was low. A lower gestational age, multiple gestation, and congenital heart disease were associated with increased risk of RSV infection.