title: Chronic respiratory morbidity following premature delivery--prediction by prolonged respiratory support requirement?
abstract: Neonatal chronic lung disease (CLD) is usually diagnosed if an infant remains oxygen dependent beyond 36 weeks postconceptional age (PCA). Our aim was to determine whether a shorter duration of respiratory support accurately predicted subsequent respiratory morbidity. A total of 103 infants, median gestational age 29 weeks (range 23-35), were followed prospectively for 5 years. They had a birth weight of < 1500 g or, if a birth weight of between 1500 and 2000 g, had required neonatal ventilatory support. Parents completed diary cards; their child had positive symptom status if, in any one year, they coughed and/or wheezed on at least 3 days per week for a 4-week period or for at least 3 days following each upper respiratory tract infection. Subsequent respiratory morbidity, positive symptom status in years 1 and 2 or all 5 pre-school years, was related to various definitions of prolonged respiratory support: intermittent positive pressure ventilation dependence > 7 days; oxygen dependence > 28 days and oxygen dependence > 36 weeks PCA. In years 1 and 2, 25 children were symptomatic and 22 in all 5 years. The patients with subsequent respiratory morbidity were distinguished from those without by requiring longer respiratory support (P < 0.05). Logistic regression analysis demonstrated only oxygen dependence beyond 28 days was independently related to subsequent respiratory morbidity (P < 0.01). The positive predictive values and likelihood ratios (95% confidence intervals) for positive symptom status in all 5 years were for intermittent positive pressure ventilation > 7 days 35% (16-53) and 19.5 (1.01-3.76), for oxygen dependency > 28 days 42% (23-61) and 2.20 (1.45-5.02) and for oxygen dependency >36 weeks PCA 35% (13-58) and 1.67 (0.65-4.31).
  
  
  CONCLUSIONS
  Oxygen dependency at 28 days of age remains a useful criterion on which to diagnose "neonatal" chronic lung disease.
authors.affiliation: Children Nationwide Regional Neonatal Intensive Care Centre, King's College Hospital, London, UK.
authors.forename: M
authors.initials: M
authors.lastname: Kinali
authors.forename: A
authors.initials: A
authors.lastname: Greenough
authors.forename: G
authors.initials: G
authors.lastname: Dimitriou
authors.forename: B
authors.initials: B
authors.lastname: Yüksel
authors.forename: R
authors.initials: R
authors.lastname: Hooper
mesh_terms: D002675:Child, Preschool; D002908:Chronic Disease; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy*; D009017:Morbidity; D011446:Prospective Studies; D012120:Respiration Disorders / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy*; D012121:Respiration, Artificial