title: Comparisons and Limitations of Current Definitions of Bronchopulmonary Dysplasia for the Prematurity and Respiratory Outcomes Program.
abstract: BACKGROUND
  Bronchopulmonary dysplasia is the most common morbidity of prematurity, but the validity and utility of commonly used definitions have been questioned.
  
  
  OBJECTIVE
  To compare three commonly used definitions of bronchopulmonary dysplasia in a contemporary prospective, multicenter observational cohort of extremely preterm infants.
  
  
  METHODS
  At 36 weeks postmenstrual age, the following definitions of bronchopulmonary dysplasia were applied to surviving infants with and without imputation: need for supplemental oxygen (Shennan definition), National Institutes of Health Workshop definition, and "physiologic" definition after a room-air challenge.
  
  
  RESULTS
  Of 765 survivors assessed at 36 weeks, bronchopulmonary dysplasia was diagnosed in 40.8, 58.6, and 32.0% of infants, respectively, with the Shennan, workshop and physiologic definitions. The number of unclassified infants was lowest with the workshop definition (2.1%) and highest with the physiologic definition (16.1%). After assigning infants discharged home in room air before 36 weeks as no bronchopulmonary dysplasia, the modified Shennan definition compared favorably to the workshop definition, with 2.9% unclassified infants. Newer management strategies with nasal cannula flows up to 4 L/min or more and 0.21 FiO2 at 36 weeks obscured classification of bronchopulmonary dysplasia status in 12.4% of infants.
  
  
  CONCLUSIONS
  Existing definitions of bronchopulmonary dysplasia differ with respect to ease of data collection and number of unclassifiable cases. Contemporary changes in management of infants, such as use of high-flow nasal cannula, limit application of existing definitions and may result in misclassification. A contemporary definition of bronchopulmonary dysplasia that correlates with respiratory morbidity in childhood is needed. Clinical trial registered with www.clinicaltrials.gov (NCT01435187).
authors.affiliation: 1 Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.|2 Indiana University School of Medicine, Indianapolis, Indiana.
authors.forename: Brenda B
authors.initials: BB
authors.lastname: Poindexter
authors.affiliation: 3 Department of Biostatistics and Epidemiology, and.
authors.forename: Rui
authors.initials: R
authors.lastname: Feng
authors.affiliation: 4 Division of Neonatology, Children's Hospital of Philadelphia, the Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Barbara
authors.initials: B
authors.lastname: Schmidt
authors.affiliation: 5 Department of Pediatrics, Albert Einstein College of Medicine and the Children's Hospital at Montefiore, Bronx, New York.|6 Monroe Carrell Jr. Children's Hospital at Vanderbilt University Medical Center, Nashville, Tennessee.
authors.forename: Judy L
authors.initials: JL
authors.lastname: Aschner
authors.affiliation: 7 Department of Pediatrics, University of California at San Francisco School of Medicine, San Francisco, California.
authors.forename: Roberta A
authors.initials: RA
authors.lastname: Ballard
authors.affiliation: 8 Ann & Robert H. Lurie Children's Hospital, Northwestern University Feinberg School of Medicine, Chicago, Illinois.|9 Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri; and.
authors.forename: Aaron
authors.initials: A
authors.lastname: Hamvas
authors.affiliation: 10 Department of Pediatrics, University of Buffalo, The State University of New York, Buffalo, New York.
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Reynolds
authors.affiliation: 3 Department of Biostatistics and Epidemiology, and.
authors.forename: Pamela A
authors.initials: PA
authors.lastname: Shaw
authors.affiliation: 1 Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors.forename: Alan H
authors.initials: AH
authors.lastname: Jobe
mesh_terms: D001997:Bronchopulmonary Dysplasia / Q000453:epidemiology* / Q000628:therapy; D019468:Disease Management; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D062071:Infant, Extremely Premature; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000453:epidemiology*; D008297:Male; D009017:Morbidity / Q000639:trends; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D011379:Prognosis; D015397:Program Evaluation / Q000379:methods*; D011446:Prospective Studies; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology
keywords: bronchopulmonary dysplasia; infant; neonatal lung disease; oxygen inhalation therapy; premature