Vitamin D Deficiency and Asthma Exacerbation

Study Overview
=================
Brief Summary
-----------------
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.

Detailed Description
-----------------
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.

Official Title
-----------------
Effect of Vitamin D Repletion on Asthma Exacerbation

Conditions
-----------------
Asthma, Vitamin D Deficiency, Disease Exacerbation

Intervention / Treatment
-----------------
* Drug: oral cholecalciferol


Participation Criteria
=================
Eligibility Criteria
-----------------
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.

Ages Eligible for Study
-----------------
Minimum Age: 12 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: asthma severity and disease exacerbation<br>intramuscular cholecalciferol 100,000 IU, followed by oral cholecalciferol 5000 IU weekly plus 400 IU daily for one year | Drug: oral cholecalciferol<br>* Inhaled corticosteroids and long-acting beta-agonists, salbutamol<br>* Other names: intramuscular cholecalciferol;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relationship between serum 25-hydroxide (OH) vitamin D level and asthma exacerbations (number/year= unscheduled visits for worsening symptoms, increase in therapy) | 119 consecutive asthmatic patients underwent serum vitamin D (25-OHD) and lung function assessment. Their medical records were retrospectively reviewed, to gain information on disease exacerbations during the 12 months preceding study entry. The relationship between baseline 25-OH vitamin D and number of exacerbation was investigated | one year | 
| Effect of vitamin D supplementation in patients with 25-OH vitamin D < 20 ng/ml on asthma exacerbations (number/year= unscheduled visits for worsening symptoms, increase in therapy) | 55 asthmatic patients with 25-OH vitamin D below 20 ng/ml underwent supplementation with cholecalciferol for one year (intramuscular 100,000 IU, followed by oral 5000 IU weekly plus 400 IU daily for one year). Number of exacerbations were recorded during the year of supplementation and compared with the data recorded during vitamin D deficiency | One year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relationship between serum 25-OH vitamin D level and airway obstruction (evaluated by spirometry: one second forced expiratory volume, FEV1 l/sec, vital capacity (VC) and FEV1/VC%) | 119 consecutive asthmatic patients underwent serum vitamin D (25-OHD, ng/ml) and lung function assessment. Their medical records were retrospectively reviewed, to gain information on lung function tests (forced expiratory volume in 1 second, FEV1, and vital capacity, VC) during the 12 months preceding study entry. The relationship between baseline 25-OH vitamin D and airway obstruction (FEV1 and FEV1/VC%) was investigated | one year | 
| Effect of vitamin D supplementation in patients with 25-OH vitamin D < 20 ng/ml on airway obstruction ( FEV1 l/sec, FEV1/VC%) | 55 asthmatic patients with 25-OH vitamin D below 20 ng/ml underwent supplementation with cholecalciferol for one year (intramuscular 100,000 IU, followed by oral 5000 IU weekly plus 400 IU daily for one year). Lung function tests (FEV1, VC and FEV1/VC%) were recorded during the year of supplementation and compared with the data recorded during vitamin D deficiency | one year | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
asthma, vitamin D, exacerbations, airway obstruction