Asthma
Conditions
Keywords
asthma, virus diseases, pediatric, RCT, steroid
Brief summary
Viral infections are the main cause of asthma attacks in preschoolers, an age group with the highest rate of emergency visits due to asthma. While high doses of inhaled or oral corticosteroids provide benefits, these have been associated with adverse outcomes. Most asthmatic children have lower blood levels of vitamin D compared to non-asthmatic children. Low vitamin D level has been linked to more frequent and more severe asthma attacks as well as with higher dose requirement of inhaled corticosteroid. Recent studies show that vitamin D supplements can reduce the number of asthma attacks triggered by viral infections in children. Unfortunately, most people forget to take vitamin D every day during the fall and winter season as recommended in Canada. A solution is to give a vitamin D bolus by mouth. This has been shown to safely and effectively increase vitamin D levels in children. The investigators hypothesise that a vitamin D bolus given in clinic will sufficiently increase the blood level of vitamin D to prevent the expected winter decline in vitamin D, compared with placebo in preschool-aged children with asthma. This six-month pilot randomized controlled trial aims to: (1) show that a vitamin D bolus is superior to placebo in raising vitamin D levels; (2) record the number of asthma attacks and viral infections in enrolled participants; and (3) identify problems that may call for protocol changes.
Interventions
DIETARY_SUPPLEMENTVitamin D
100,000IU cholecalciferol given in a 2ml dose by mouth at baseline.
DIETARY_SUPPLEMENTdaily vitamin D supplement
Each group receives a daily vitamin D supplement for 6 months, providing 400IU per day.
OTHERPlacebo
placebo given in a 2ml dose by mouth at baseline.
Sponsors
St. Justine's Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)
Eligibility
Sex/Gender
ALL
Age
1 Years to 5 Years
Healthy volunteers
No
Inclusion criteria
* children aged 1-5 years * physician-diagnosed asthma as per GINA guidelines * upper respiratory tract infections as the main asthma exacerbation trigger * ≥4 respiratory infections in the past 12 months * ≥1 exacerbation requiring rescue oral steroids in the past 6 months or ≥2 in the previous 12 months.
Exclusion criteria
* extreme prematurity (\<28 weeks gestation) * infants \<12 months of age * breastfed infants with no vitamin D supplementation * recent (\<1 year) immigrants from countries where rickets and malnutrition prevalent * other chronic respiratory disease (broncho-pulmonary dysplasia; cystic fibrosis) * endocrine disorder of calcium/ vitamin D metabolism * disorder/ disease with associated malabsorption (inflammatory bowel disease) * kidney/ liver disease * sickle cell anemia * medications known to interfere with bone metabolism/ vitamin D levels * vitamin D supplementation \>1000 IU/ day in past 3 months * unable to attend medical visit in 3-4 months * plan to leave the province during the next 6 months.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| serum Vitamin D | 3 months | mean change in serum vitamin D from baseline to 3 months |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| adequate serum vitamin D | 3 months | difference in the proportion of children with serum vitamin D ≥75nmol/L at 3 months |
Other
| Measure | Time frame | Description |
|---|---|---|
| Hypercalciuria | any point during the 6 months | urinary calcium: creatinine ratio \>1.25 (1-2 years) and \>1 (2-5 years) mmol/mmol |
| Cytokine/ chemokine profile | 10 days | change in serum cytokine/ chemokine profile from baseline to 10 days post-bolus dose |
| duration of viral infections | in the event of a cold during the 6 months | number of days with respiratory tract symptoms as reported on the parent completed Canadian Acute Respiratory Illness & Flu Scale |
| exacerbations requiring oral corticosteroids | 6 months | number of patients with one or more exacerbations requiring oral steroids, as documented by pharmacy dispensation records and medical records |
| duration of exacerbations | in the event of an exacerbation during the 6 months | Number of days with asthma symptoms as reported on the parent-reported 'Asthma Flare-Up Diary for Young Children' |
| participant retention | 6 months | percentage of patients retained until 6 months after randomization |
| protocol adherence | 6 months | 1. participant attendance to all 4 home and clinic visits 2. percentage of patients with all 4 blood and urine tests collected 3. percentage of analyzable viral nasal swabs returned. |
| severity of exacerbations | in the event of an exacberbation during the 6 months | 1. area under the curve for β-agonist use as documented by parent of the 'Asthma Flare-Up Diary for Young Children'; 2. need for hospital admission |
| number of viral infections | 6 months | number of patients/person-month of observation documented two days 1. parent-reported on the Canadian Acute Respiratory Illness and Flu Scale and 2. Positive viral presence, determined by polymerase chain reaction on nasal sample |
Countries
Canada
Outcome results
None listed