Vitamin D Deficiency and Asthma Exacerbation
Vitamin D Deficiency and Asthma Exacerbation
The study aim is in two phases. First phase: to evaluate the influence of vitamin D
 deficiency on asthma severity, degree of airway obstruction and frequency of asthma
 exacerbations. Second phase: to evaluate if in patients with vitamin D deficiency (25-OH
 vitamin D levels below 20 ng/ml), vitamin D supplementation decreases the number of disease
 exacerbations.
The first phase of the study consisted of a cross-sectional examination of a cohort of 119
 asthmatic patients, who had at least one year regular follow-up in our respiratory clinic,
 and were not receiving any vitamin D supplementation.

 In the second phase patients with vitamin D deficiency (25-OH D values below 20 ng/ml), were
 recruited in a one year longitudinal study, during which they received vitamin D
 supplementation. The study started and ended in late autumn-winter season when, at our
 latitude, sun exposure is lowest. Symptoms, spirometry and number of exacerbations were
 recorded during both study phases.
Inclusion Criteria:

 -  All the consecutive patients with bronchial asthma of any severity, who presented for
 a scheduled visit at our Respiratory Clinic during the period October 2012-March 2013
 and who had at least one year regular follow-up every three months

 Exclusion Criteria:

 -  Acute exacerbation in the last month and treatment with vitamins and dietary
 supplements in the last year.