Persistence of respiratory symptoms into the second year of life: predictive factors in infants born preterm

Preterm infants frequently suffer from recurrent respiratory symptoms in the first year of life. Our aims were to assess if such respiratory morbidity persisted beyond the first year and to define the predictive factors. One hundred and seventeen infants (median gestational age 29 weeks) were followed prospectively for two years. Thirty-eight infants had symptoms only in the first year (group A) and in a further 20 infants, symptoms were present in both years (group B). Comparison of these two groups revealed no significant difference in birth weight or gestational age, but the duration of ventilation and increased inspired oxygen concentration were significantly longer in group B. Significantly more infants in group B had had an air leak in the neonatal period, and airways resistance at six months of age was also significantly higher in group B. We conclude that infants with severe neonatal respiratory distress are likely to have persisting respiratory morbidity and that respiratory function measurements at six months of age provide the most accurate predictor of chronic respiratory symptoms.