Risk Factors for Severe Respiratory Morbidity at 6 Months and 2 Years of Life in Children Born Extremely Prematurely with Bronchopulmonary Dysplasia: Retrospective and Prospective Studies

Abstract

Prematurity-associated lung disease remains a significant cause of respiratory morbidity beyond neonatal intensive care unit (NICU) discharge. This thesis evaluated predictors of post- prematurity respiratory disease (PRD) using both a retrospective cohort assessing PRD at 2 years of life, and a prospective multicentre cohort assessing PRD at 6 months corrected age. Clinical and physiological predictors were examined using univariable and multivariable Firth penalized logistic regression modeling. In the retrospective cohort, bronchopulmonary dysplasia (BPD), pulmonary hypertension, and elevated pCO₂ at discharge were associated with later PRD, with moderate discriminatory ability. In the prospective cohort, discharge on home supplemental oxygen and post-menstrual age at discharge were the strongest predictors of early PRD. These findings suggest that aspects of respiratory status and diagnoses at discharge may identify infants at risk for early morbidity and later PRD reflective of more established chronic lung pathology. Multivariable approaches may improve early risk stratification in this population.