title: Lack of a relation between serum 25-hydroxyvitamin D concentrations and asthma in adolescents.
abstract: BACKGROUND
  Decreased 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with an increased prevalence and severity of asthma and a lower response to inhaled corticosteroids.
  
  
  OBJECTIVE
  The objective was to determine the association between serum 25(OH)D concentrations and asthma prevalence, severity, and response to asthma treatment.
  
  
  METHODS
  Secondary analyses were conducted in 2 samples of adolescents 12-20 y of age: 1) NHANES 2001-2006 (n = 6487), a cross-sectional nationally representative sample of the US population, and 2) a cohort of inner-city adolescents with asthma managed prospectively for 46 wk with guidelines-based therapy in the Asthma Control Evaluation (ACE; n = 226) trial.
  
  
  RESULTS
  Mean (±SD) serum 25(OH)D concentrations in the NHANES and ACE samples were lower in African Americans than in non-African Americans (NHANES: 14.9 ± 6.5 compared with 23.0 ± 8.4 ng/mL, P < 0.0001; ACE: 11.2 ± 6.9 compared with 15.8 ± 7.1 ng/mL, P < 0.0001). In the NHANES sample, mean concentrations did not differ between participants without and with asthma (African Americans: 14.9 ± 6.4 compared with 15.0 ± 6.6 ng/mL, respectively, P = 0.87; non-African Americans: 23.0 ± 8.5 compared with 23.6 ± 8.2 ng/mL, respectively, P = 0.16). In the ACE models that used either a predefined cutoff (<20 ng/mL) or linear regression, 25(OH)D concentrations showed either no relation or minor contradictory correlations with indicators of asthma severity, treatment requirements, spirometry, or atopy/inflammation.
  
  
  CONCLUSIONS
  In 2 samples of adolescents, overall serum 25(OH)D concentrations were low and were not consistently associated with the presence of asthma, multiple asthma characteristics, asthma morbidity, or response to treatment. The ACE trial was registered at clinicaltrials.gov as NCT0011441.
authors.affiliation: National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA. pgergen@niaid.nih.gov
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Gergen
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Teach
authors.forename: Herman E
authors.initials: HE
authors.lastname: Mitchell
authors.forename: Robert F
authors.initials: RF
authors.lastname: Freishtat
authors.forename: Agustin
authors.initials: A
authors.lastname: Calatroni
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Matsui
authors.forename: Meyer
authors.initials: M
authors.lastname: Kattan
authors.forename: Gordon R
authors.initials: GR
authors.lastname: Bloomberg
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Liu
authors.forename: Carolyn
authors.initials: C
authors.lastname: Kercsmar
authors.forename: George
authors.initials: G
authors.lastname: O'Connor
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Pongracic
authors.forename: Yadira
authors.initials: Y
authors.lastname: Rivera-Sanchez
authors.forename: Wayne J
authors.initials: WJ
authors.lastname: Morgan
authors.forename: Christine A
authors.initials: CA
authors.lastname: Sorkness
authors.forename: Neil
authors.initials: N
authors.lastname: Binkley
authors.forename: William
authors.initials: W
authors.lastname: Busse
mesh_terms: D000293:Adolescent; D001741:Black or African American; D001249:Asthma / Q000097:blood* / Q000150:complications / Q000453:epidemiology*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D017058:Mexican Americans; D015999:Multivariate Analysis; D009749:Nutrition Surveys; D015995:Prevalence; D016032:Randomized Controlled Trials as Topic; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000150:complications; D044465:White People; D055815:Young Adult
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D