title: Revisiting the Definition of Bronchopulmonary Dysplasia: Effect of Changing Panoply of Respiratory Support for Preterm Neonates.
abstract: Several definitions of bronchopulmonary dysplasia are clinically used; however, their validity remains uncertain considering ongoing changes in the panoply of respiratory support treatment strategies used within neonatal units.
  
  
  
  To identify the optimal definition of bronchopulmonary dysplasia that best predicts respiratory and neurodevelopmental outcomes in preterm infants.
  
  
  
  Retrospective cohort study at tertiary neonatal intensive care units. Preterm infants born at less than 29 weeks' gestation between 2010 and 2011 who were admitted to neonatal intensive care units participating in the Canadian Neonatal Network and completed follow-up assessments in a Canadian Neonatal Follow-Up Network clinic at 18 to 21 months.
  
  
  
  Various traditional bronchopulmonary dysplasia criteria based on respiratory status at different postmenstrual ages.
  
  
  
  Serious respiratory morbidity, neurosensory impairment at 18 to 21 months of age, and a composite outcome of respiratory or neurosensory morbidity or death after discharge. Adjusted odds ratios (AORs) and 95% CIs were calculated.
  
  
  
  Of 1914 eligible survivors, 1503 were assessed (mean gestational age was 26.3 weeks; 68% were white, 9% were black, and 23% were other race/ethnicity), 88 had serious respiratory morbidity, 257 infants had neurosensory impairment, and 12 infants died after discharge. Definitions using oxygen requirement alone as the criterion at various postmenstrual ages were less predictive compared with those using the criterion of oxygen/respiratory support (RS) (receiving supplemental oxygen and/or positive-pressure RS); among those, oxygen/RS at 36 weeks had the highest AOR and area under the curve (AUC) for all outcomes. Further analyses of oxygen/RS at each week between 34 and 44 weeks' postmenstrual age indicated that the predictive ability for serious respiratory morbidity increased from 34 weeks (AOR, 1.8; 95% CI, 0.9-3.4, AUC, 0.721) to 40 weeks (AOR, 6.1; 95% CI, 3.4-11.0; AUC, 0.799). For serious neurosensory impairment, the AOR and AUC at 40 weeks' PMA (AOR, 1.5, 95% CI, 1.0-2.1; AUC, 0.740) were only marginally below their peak values at 37 weeks' PMA (AOR, 1.8; 95% CI, 1.3-2.6; AUC, 0.743).
  
  
  
  Defining bronchopulmonary dysplasia by the use of oxygen alone is inadequate because oxygen/RS is a better indicator of chronic respiratory insufficiency. In particular, oxygen/RS at 40 weeks' PMA was identified as the best predictor for serious respiratory morbidity, while it also displayed a good ability to predict neurosensory morbidity at 18 to 21 months.
authors.affiliation: Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada2Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Isayama
authors.affiliation: Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada3Maternal-Infant Care Research Centre, Department of Paediatrics, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Shoo K
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Maternal-Infant Care Research Centre, Department of Paediatrics, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Junmin
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Paediatrics, University of Western Ontario, London, Ontario, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Lee
authors.affiliation: Department of Paediatrics, University of Saskatchewan, Saskatoon, Canada.
authors.forename: Sibasis
authors.initials: S
authors.lastname: Daspal
authors.affiliation: Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Dunn
authors.affiliation: Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada3Maternal-Infant Care Research Centre, Department of Paediatrics, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Prakesh S
authors.initials: PS
authors.lastname: Shah
mesh_terms: D019540:Area Under Curve; D001997:Bronchopulmonary Dysplasia / Q000150:complications / Q000175:diagnosis* / Q000628:therapy; D002170:Canada; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D007363:Intensive Care Units, Neonatal; D008297:Male; D010102:Oxygen Inhalation Therapy / Q000706:statistics & numerical data; D011175:Positive-Pressure Respiration / Q000706:statistics & numerical data; D012189:Retrospective Studies