title: Serum 25-hydroxyvitamin D levels and incident asthma in adults: the HUNT Study.
abstract: The impact of low vitamin D status on asthma development is unclear. The authors investigated the relation between the baseline serum 25-hydroxyvitamin D (25(OH)D) level and incident asthma in adults, including possible effect modification by allergy status, using allergic rhinitis as a proxy measure. A cohort of 25,616 Norwegian adults aged 19-55 years participated in 2 surveys of the Nord-Trøndelag Health Study known as HUNT 2 (1995-1997) and HUNT 3 (2006-2008). Of this cohort, a nested case-control study included 584 new-onset asthma cases and 1,958 nonasthma controls whose baseline serum 25(OH)D levels were measured. After adjustment for potential asthma risk factors, the baseline serum level of 25(OH)D (<50 nmol/L) was not significantly associated with asthma in either women (adjusted odds ratio = 0.94, 95% confidence interval (CI): 0.67, 1.32) or men (adjusted odds ratio = 1.47, 95% CI: 0.93, 2.32). In men, allergic rhinitis modified the association with the adjusted odds ratio being 0.87 (95% CI: 0.36, 2.06) among men with allergic rhinitis and 2.32 (95% CI: 1.06, 5.10) among men without allergic rhinitis. The serum 25(OH)D level was not associated with incident asthma in women, regardless of allergy status. Low vitamin D status was not significantly associated with incident asthma in most adults, but it may have increased risk among men without allergy.
authors.affiliation: Department of Public Health and General Practice, Faculty of Medicine, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway. xiao-mei.mai@ntnu.no
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Mai
authors.forename: Arnulf
authors.initials: A
authors.lastname: Langhammer
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Camargo
authors.forename: Yue
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000328:Adult; D001249:Asthma / Q000453:epidemiology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009664:Norway / Q000453:epidemiology; D011446:Prospective Studies; D065631:Rhinitis, Allergic; D012221:Rhinitis, Allergic, Perennial / Q000453:epidemiology; D012307:Risk Factors; D017678:Sex Distribution; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D