Vitamin D and Severe Asthma Exacerbations
Condition: Asthma
MeSH terms: Asthma
Intervention: Cholecalciferol
Intervention description: vitamin D supplementation with either 2,000 IU/day or 4,000 IU/day compared to vitamin D3 supplementation with 200 IU/day.
Intervention MeSH terms: Vitamin D; Cholecalciferol
Phase: Phase 1
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Enrollment: 48.0
Sex: All
Minimum age: 6 Years
Maximum age: 14 Years
Healthy volunteers: No
Keywords: asthma; vitamin D

Summary:

      This study of vitamin D is designed to assess both the safety and efficacy of potential doses
      (2,000 IU/day and 4,000 IU/day) in raising a vitamin D level to a normal range in a short
      period of time (e.g. 4 weeks or less) compared to 200 IU/day.

      In children with vitamin D insufficiency or deficiency who are at risk for severe asthma
      exacerbations, we hypothesize that both vitamin D supplementation with 4,000 IU/day and 2,000
      IU/day will safely achieve normal vitamin D levels, but that the higher dose (4,000 IU/day)
      will result in a larger proportion of subjects achieving this level at 4 and 8 weeks.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Be at least 6 years of age and younger than 15 years of age

          -  Have physician-diagnosed asthma

          -  Taking a medium dose of ICS (e.g. fluticasone 220mcg BID) for daily asthma control for
             at least 6 months in the prior year.

          -  Have had a severe asthma exacerbation in the previous year, defined as an Emergency
             Department (ED) visit, hospitalization, or unscheduled clinic visit for asthma
             resulting in intramuscular, intravenous, or oral steroids.

          -  Have bronchodilator responsiveness (BDR, an increase in FEV1 ≥12% from baseline after
             administration of inhaled albuterol) or (if no BDR) increased airway responsiveness to
             methacholine challenge

          -  Have vitamin D insufficiency (a serum vitamin D (25(OH)D) level <30 ng/ml)

          -  Have his/her parents give voluntary written consent to participate in the study

        Exclusion Criteria:

          -  Chronic respiratory disorder other than asthma (e.g., bronchiectasis).

          -  Severe asthma, as evidenced by any of the following: a) chronic need for medication
             other than single controller therapy and inhaled β2-agonist, b) intubation for asthma
             at any time, and c) ≥2 hospitalizations or ≥6 severe asthma exacerbations in the
             previous year

          -  History of cigarette smoking in the prior year or former smoking if ≥5 pack-years

          -  Hepatic or renal disease, metabolic rickets, malabsorptive disorders, or other chronic
             diseases that would affect vitamin D metabolism

          -  Immune deficiency, cleft palate or Down's syndrome, which might increase the child's
             likelihood of respiratory infections

          -  Treatment with anticonvulsants or pharmacological doses of vitamin D (≥1,000 IU/day of
             vitamin D2 or D3)

          -  Chronic oral corticosteroid therapy

          -  Inability to perform acceptable spirometry

          -  Use of investigational therapies or participation in clinical trials 30 days before or
             during the duration of the study

          -  Serum calcium >10.8 mg/dl

          -  Serum 25(OH) D <10 ng/ml (severe vitamin D deficiency)