TY - JOUR T1 - Bronchial Reactivity, Inflammatory and Allergic Parameters, and Vitamin D Levels in Children With Asthma JF - Respiratory Care SP - 1157 LP - 1163 DO - 10.4187/respcare.03763 VL - 60 IS - 8 AU - Husein Dabbah AU - Ronen Bar Yoseph AU - Galit Livnat AU - Fahed Hakim AU - Lea Bentur Y1 - 2015/08/01 UR - http://rc.rcjournal.com/content/60/8/1157.abstract N2 - BACKGROUND: A low serum vitamin D level may represent a marker of other perplexing factors that may lead to increased asthma prevalence and severity. Our aim was to assess the correlation between vitamin D levels and asthma and allergy markers in a subgroup of children with fewer confounding factors.METHODS: Non-obese children (6–18 y old) with asthma who were not receiving anti-inflammatory treatment were recruited. Subjects underwent spirometry with a methacholine challenge test, and fractional exhaled nitric oxide (FENO), serum vitamin D levels, total immunoglobulin E (IgE) levels, blood eosinophil counts, and high-sensitivity C-reactive protein levels were determined. The primary end point was the correlation between vitamin D level and airway hyper-responsiveness as assessed by a methacholine challenge test. The secondary end point was the correlation between vitamin D level and FENO, systemic inflammatory markers, and allergy.RESULTS: Seventy-one children with asthma (25 females, 35%; 12.5 ± 3.6 y of age) were included. The median vitamin D level was 23 ng/mL (range of 6–48.5, mean of 23.02 ± 7.74), the median IgE level was 305 IU/mL (range of 4.3–4,240), the median provocational concentration of methacholine that produced a 20% decrease in FEV1 was 1.1 mg/mL (range of 0–13.9), and the median FENO was 26.5 ppb (range of 3.6–285). No correlation was found between vitamin D level and response to the methacholine challenge test, FENO, high-sensitivity C-reactive protein levels, IgE levels, eosinophil counts, and frequency of allergic rhinitis or atopic dermatitis.CONCLUSIONS: In our group of children with asthma, no correlation was found between the level of vitamin D and the degree of airway reactivity, airway inflammation, and allergy. The cause-and-effect relationship between vitamin D, asthma, and allergy should be further clarified. (ClinicalTrials.gov registration NCT01287455) ER -