Infant Pulmonary Function Testing and Phenotypes in Severe Bronchopulmonary Dysplasia.

Area of Science:

• Neonatal Medicine
• Pediatric Pulmonology
• Respiratory Physiology

Background:

• Severe bronchopulmonary dysplasia (sBPD) management is empirical and varies widely.
• Current sBPD definition relies on respiratory support needs.
• Distinct patient phenotypes within sBPD are suspected but not well-defined.

Purpose of the Study:

• To test the hypothesis that infant pulmonary function testing (iPFT) reveals distinct phenotypes in infants with sBPD.
• To characterize these phenotypes during the initial NICU stay.

Main Methods:

• Prospective cohort study of infants with sBPD (May 2003-June 2016).
• Infant pulmonary function testing (iPFT) used for classification.
• Patients categorized into obstructive, restrictive, or mixed phenotypes based on iPFT data.

Main Results:

• 51% obstructive, 40% mixed, and 9% restrictive phenotypes identified.
• 86% of obstructive and 78% of mixed groups showed moderate/severe obstruction.
• 70% of restrictive patients had moderate restriction; 74% of obstructive and 63% of mixed groups responded to bronchodilators.

Conclusions:

• Severe BPD encompasses distinct pulmonary function phenotypes.
• Future diagnostic approaches should focus on bedside phenotyping.
• Therapeutic trials should consider pulmonary function phenotyping for patient selection.