Early-life respiratory trajectories and neurodevelopmental outcomes in infants born very and extremely preterm: A retrospective study

Aim: To determine whether early-life respiratory trajectories are associated with neurodevelopmental impairment (NDI) in infants born very and extremely preterm. Method: The daily type of respiratory supports in the first 8 weeks after birth were analysed in 546 infants (285 males, 261 females; median gestational age = 28.0 weeks, interquartile range = 3 weeks), comprising 301 infants born very preterm (gestation = 28–30 weeks) and 245 infants born extremely preterm (gestation <28 weeks), who survived to discharge from 2004 to 2018 and received follow-up assessment by Bayley Scales of Infant and Toddler Development at a corrected age of 24 months. NDI included cognition or motor impairment, moderate and severe cerebral palsy, or visual and hearing impairment. Results: Clustering analysis identified three respiratory patterns with increasing severity: improving; slowly improving; and delayed improvement. These were significantly associated with increasing rates of NDI in infants born very and extremely preterm and smaller head circumference in infants born extremely preterm (both p < 0.001). By day 28, the proportion of infants who were under different categories of ventilation support significantly differed according to the three trajectory groups in infants born very and extremely preterm (both p < 0.05). Models that included adverse respiratory trajectories demonstrated more negative impacts on neurodevelopment than those without. Interpretation: An adverse early-life respiratory trajectory was associated with NDI at follow-up, especially in infants born extremely preterm, suggesting a lung–brain axis of preterm birth. What this paper adds: Clustering analysis identified three respiratory trajectories with increasing severity in infants born preterm. Increasing severity of respiratory trajectories was associated with increasing rates of neurodevelopmental impairment. Adverse respiratory trajectories had a significantly negative impact on neurodevelopmental outcomes.