title: Reduced exercise capacity in children born very preterm.
abstract: OBJECTIVE
  In the past 20 years, there has been an increase in survivors of very preterm birth, but little is known regarding their long-term respiratory and fitness outcomes. We aimed to assess the 10-year lung function and fitness outcomes for children who were born weighing <1000 g and before 32 weeks' gestation in 1992-1994.
  
  
  METHODS
  A cross-sectional study was conducted of 126 children (mean age: 10 years) who were born at a mean gestation of 27 weeks and 34 term-born control subjects. Extensive lung function (spirometry, lung volumes, and gas exchange) and fitness (6-minute walk and 20-m shuttle run tests) assessments were conducted at a single visit according to previously validated techniques.
  
  
  RESULTS
  The preterm group had significantly lower values for all measured spirometric parameters compared with the control group. In contrast to airflow, the preterm group had significantly higher percentage predicted values in all standard lung-volume parameters and transfer factor than the control group. The exercise capacity of the preterm group was approximately half that of the control group. There was no significant difference in the distance walked in the 6-minute walk test.
  
  
  CONCLUSIONS
  In the largest cohort of school-aged children (born very preterm in the 1990s) to undergo extensive lung function and fitness assessments, we demonstrated significant impairment in exercise capacity despite evidence of only mild small-airway obstruction and gas trapping. Additional studies are required to evaluate the cause of this exercise limitation and whether it can be improved with a training program.
authors.affiliation: Department of Respiratory Medicine, Children's Hospital at Westmead, Westmead, Sydney, New South Wales, Australia. m_gsmith@optusnet.com.au
authors.forename: Lucia Jane
authors.initials: LJ
authors.lastname: Smith
authors.forename: Peter Paul
authors.initials: PP
authors.lastname: van Asperen
authors.forename: Karen Olwyn
authors.initials: KO
authors.lastname: McKay
authors.forename: Hiran
authors.initials: H
authors.lastname: Selvadurai
authors.forename: Dominic Adam
authors.initials: DA
authors.lastname: Fitzgerald
mesh_terms: D000403:Airway Resistance; D001997:Bronchopulmonary Dysplasia / Q000150:complications* / Q000175:diagnosis / Q000628:therapy; D002648:Child; D003430:Cross-Sectional Studies; D002658:Developmental Disabilities / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D007363:Intensive Care Units, Neonatal; D008297:Male; D009517:New South Wales; D010809:Physical Fitness / Q000502:physiology; D011336:Probability; D012123:Pulmonary Ventilation; D012016:Reference Values; D012129:Respiratory Function Tests; D013147:Spirometry