title: Children and young adults with CF in the USA have better lung function compared with the UK.
abstract: BACKGROUND
  People with cystic fibrosis (CF) are managed differently in the USA and UK providing an opportunity to learn from differences in practice patterns.
  
  
  OBJECTIVE
  To compare cross-sectional demographics, practice patterns and clinical outcomes between US and UK CF patients.
  
  
  METHODS
  This was a cross-sectional study using 2010 data from patients in the US Cystic Fibrosis Foundation and the UK Cystic Fibrosis patient registries. The a priori outcome measures of interest were lung function and nutritional status. Descriptive statistics and two sample comparisons were performed. Stratification and multivariable linear regression were used to adjust for confounding.
  
  
  RESULTS
  The study cohort included 13 777 children and 11 058 adults from the USA and 3968 children and 3965 adults from the UK. In children, mean body mass index centiles were similar. Lung function (FEV1 and FVC% predicted) was significantly higher in US patients ages 6-25 years of age. In a regression model adjusted for only age, FEV1% predicted was on average 3.31% of predicted (95% CI 2.65 to 3.96) higher in the USA compared with the UK. When adjusted for age, age at diagnosis, gender, pancreatic insufficiency and genotype, FEV1% predicted was on average 3.03% of predicted (95% CI 2.37 to 3.69) higher in the USA compared with the UK These differences persisted despite adjustment for possible confounders. Hypertonic saline and dornase alfa were much more commonly prescribed in US children.
  
  
  CONCLUSIONS
  Children and young adults with CF have better lung function in the USA compared with the UK despite similar nutritional status.
authors.affiliation: Department of Medicine, University of Washington, Seattle, Washington, USA.
authors.forename: Christopher H
authors.initials: CH
authors.lastname: Goss
authors.affiliation: Department of Occupational and Environmental Medicine, Imperial College London, London, UK.
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: MacNeill
authors.affiliation: Value Reporting and Analytics, Dartmouth-Hitchcock Medical Center, Hanover, New Hampshire, USA.
authors.forename: Hebe B
authors.initials: HB
authors.lastname: Quinton
authors.affiliation: Cystic Fibrosis Foundation, Bethesda, Maryland, USA.
authors.forename: Bruce C
authors.initials: BC
authors.lastname: Marshall
authors.affiliation: Cystic Fibrosis Foundation, Bethesda, Maryland, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Elbert
authors.affiliation: Cystic Fibrosis Foundation, Bethesda, Maryland, USA.
authors.forename: Emily A
authors.initials: EA
authors.lastname: Knapp
authors.affiliation: Cystic Fibrosis Foundation, Bethesda, Maryland, USA.
authors.forename: Kristofer
authors.initials: K
authors.lastname: Petren
authors.affiliation: UK Cystic Fibrosis Trust, London, UK.
authors.forename: Elaine
authors.initials: E
authors.lastname: Gunn
authors.affiliation: UK Cystic Fibrosis Trust, London, UK.
authors.forename: Joanne
authors.initials: J
authors.lastname: Osmond
authors.affiliation: Department of Respiratory Medicine, Royal Brompton Hospital, London, UK.
authors.forename: Diana
authors.initials: D
authors.lastname: Bilton
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D015992:Body Mass Index; D002648:Child; D003430:Cross-Sectional Studies; D003550:Cystic Fibrosis / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology*; D003850:Deoxyribonuclease I / Q000627:therapeutic use; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status / Q000502:physiology*; D010818:Practice Patterns, Physicians'; D011994:Recombinant Proteins / Q000627:therapeutic use; D012462:Saline Solution, Hypertonic / Q000627:therapeutic use; D006113:United Kingdom; D014481:United States; D014797:Vital Capacity; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D011994:Recombinant Proteins; D012462:Saline Solution, Hypertonic; D003850:Deoxyribonuclease I; C568813:dornase alfa
keywords: Clinical Epidemiology; Cystic Fibrosis; Paediatric Lung Disaese