Presented at the Neonatal Society 2001 Summer Meeting.
Thomas M, Greenough A, Johnson A*, Limb E*, Marlow N**, Peacock J*, Calvert S*
Departments of Child Health, King’s College Hospital, *St George’s Hospital Medical Schools, London and **University Hospital, Nottingham, UK
Background: Preterm infants, particularly those born at very early gestations, frequently suffer recurrent cough and wheeze at follow-up.
Aim: To determine whether the chest radiograph (CXR) appearance at 28 days or 36 weeks postconceptional age (PCA) predicted such problems and was a better predictor than readily available clinical data.
Patients: One hundred infants with a median gestational age of 26 weeks (range 23-28) entered into the UKOS trial were studied.
Methods: Chest radiographs taken at 28 days and 36 weeks PCA were assessed using a scoring system for the presence of fibrosis/interstitial shadows, cystic elements and hyperinflation. At 6 months of age corrected for prematurity, the occurrence and frequency of cough and wheeze since discharge were determined using a symptom questionnaire.
Results: Seventeen infants were reported to wheeze more than once a week. Compared to those who did not, they had a higher total chest radiograph score at 36 weeks PCA (p<0.05), with higher scores for fibrosis/interstitial shadows (p<0.05) and cystic elements (p<0.01), but had similar chest radiograph scores at 28 days. Gestational age, birthweight, the proportions with a family history of atopy, maternal smoking during or after pregnancy, the duration of ventilation and chronic lung disease status were also similar in the two groups. The 20 infants with cough more than once a week only differed significantly from the rest of the cohort with regard to their higher CXR score for cystic elements at 36 weeks PCA (p<0.05). Construction of receiver operator characteristic curves revealed that the total CXR score at 36 weeks PCA was the best predictor of frequent wheeze.
Conclusion: The CXR appearance at 36 weeks PCA, but not at 28 days, predicts recurrent wheeze at follow-up in very preterm infants more accurately than readily available clinical data.