Vitamin D in non-allergic asthma.

Non-atopic asthma is often more severe than classic allergic asthma. It
is associated with neutrophilic airway inflammation and decreased
steroid responsiveness and therapies other than steroids are needed. Recently, accumulating epidemiological data are linking a low vitamin D nutritional status to asthma, respiratory infections and nasal polyps. In line with the novel insights on the immune function of vitamin D, it is tempting to speculate that vitamin D may down-regulate the neutrophilic immune response in the airways while boosting innate immune defence against different microorganisms. In addition, vitamin D may play a therapeutic role in steroid resistance. We
hypothesize that treatment with high dose vitamin D will decrease
neutrophilic and eosinophilic airway inflammation and improve asthma control. 62 patients
with predominantly neutrophilic and/or eosinophilic airway inflammation are given one high
dose of vitamin D (400.000 IU) or placebo. Primary outcome will be the
change in percentage of neutrophils and/or eosinophils in induced sputum. Secondary
outcomes will be the effect of supplementation of a single high dose of
vitamin D on the percentage of eosinophils in induced sputum, extent of
sinus disease as measured on CT-sinus, pulmonary function (FEV1), levels
of exhaled nitric oxide (NO), quality of life (AQLQ), asthma control
(ACQ) and adverse events in non-atopic asthmatic patients and to
identify potential predictors of response.

We hypothesize that supplementation of high doses of vitamin D in non-atopic asthmatic patients can reduce neutrophilic and/or eosinophilic airway inflammation.

1. Baseline;

2. 8-10 weeks after vitamin D administration.

Patients recieve a single dose of vitamin D (cholecalciferole) of 400.000IU or placebo orally.