title: Relationship of vitamin D status to adult lung function and COPD.
abstract: BACKGROUND
  There is considerable interest in the possible role of vitamin D in respiratory disease, but only one population-based study has reported associations with lung function.
  
  
  METHODS
  The cross-sectional relationships of total dietary vitamin D intake, serum 25 hydroxy vitamin D (25(OH)D) concentrations and three vitamin D receptor (VDR) polymorphisms (Apa1, Fok1 and Cdx2) with lung function and spirometrically-defined chronic obstructive pulmonary disease (COPD) were investigated in men and women aged 59-73 years in the Hertfordshire Cohort Study, UK.
  
  
  RESULTS
  After controlling for confounders, total vitamin D intake was positively associated with forced expiratory volume in 1 s (FEV(1); difference in FEV(1) between top and bottom quintiles of intake 0.079 l (95% CI 0.02 to 0.14), p trend=0.007, n=2942), ratio of FEV(1) to forced vital capacity (FEV(1)/FVC; p trend=0.008) and negatively associated with COPD (OR comparing top and bottom quintiles 0.57 (95% CI 0.38 to 0.87), p trend=0.02). In contrast, serum 25(OH)D concentrations were not related to FEV(1) (p trend=0.89, n=1197) but were positively associated with COPD (p trend=0.046). VDR genotypes were unrelated to lung function and did not modify the effects of dietary intake or 25(OH)D concentrations on lung function.
  
  
  CONCLUSIONS
  The results of this study did not confirm a positive association between blood 25(OH)D concentrations and adult lung function. The apparent relationships with dietary vitamin D are likely to be explained by other highly correlated nutrients in the diet.
authors.affiliation: Centre for Primary Care and Public Health, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 2 Newark Street, Whitechapel, London E1 2AT, UK. s.shaheen@qmul.ac.uk
authors.forename: Seif O
authors.initials: SO
authors.lastname: Shaheen
authors.forename: Karen A
authors.initials: KA
authors.lastname: Jameson
authors.forename: Sian M
authors.initials: SM
authors.lastname: Robinson
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Boucher
authors.forename: Holly E
authors.initials: HE
authors.lastname: Syddall
authors.forename: Avan Aihie
authors.initials: AA
authors.lastname: Sayer
authors.forename: Cyrus
authors.initials: C
authors.lastname: Cooper
authors.forename: John W
authors.initials: JW
authors.lastname: Holloway
authors.forename: Elaine M
authors.initials: EM
authors.lastname: Dennison
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D004032:Diet; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood* / Q000235:genetics / Q000503:physiopathology; D018167:Receptors, Calcitriol / Q000235:genetics; D012621:Seasons; D012959:Socioeconomic Factors; D013147:Spirometry / Q000379:methods; D014797:Vital Capacity / Q000502:physiology; D014807:Vitamin D / Q000008:administration & dosage* / Q000031:analogs & derivatives / Q000097:blood
chemical_list: D018167:Receptors, Calcitriol; D014807:Vitamin D; C104450:25-hydroxyvitamin D