Bronchopulmonary dysplasia Definitions and outcomes

This dissertation investigates bronchopulmonary dysplasia (BPD), a common complication of preterm birth. Unfortunately, the incidence is not decreasing over time and BPD is associated with lifelong adverse effects.
Part I focuses on the relationship between BPD and neurodevelopmental outcomes, demonstrating that with increasing severity of BPD, preterm infants have a significantly increased risk of neurodevelopmental impairment (NDI) at two- and five-year corrected age (CA). However, only infants with the most severe grade of BPD showed a significantly increased risk of NDI compared to preterm infants without a BPD diagnosis. Additionally, research was conducted on preterm infants with moderate and severe BPD, identifying birth weight and small for gestational age at two-years CA, and also male gender at five years as independent risk factors.
In Part II, three different BPD definitions are examined and compared. The investigated BPD definitions have similar predictive power for respiratory and neurological outcomes at two- and five years CA. Furthermore, the three definitions show similar accuracy of risk stratification (calibration) for short-term and long-term outcomes. A systematic review demonstrates significant variability in BPD incidence according to different BPD definitions. Additionally, BPD definitions published in the 21st century appear to be better predictors than those from before this time. Finally, a study protocol for a Delphi procedure on BPD definitions was developed. The aim of this study is to strive for a harmonized BPD definition, focusing on the questions (why, how, and when) regarding the BPD diagnosis.