Pediatric Allergy and Immunology, DOI: 10.1111/pai.12547
Conor P. Kerley1,2,4,*, Katrina Hutchinson3, Liam Cormican4, John Faul4, Peter Greally1, David Coghlan5 and Basil Elnazir1
- Asthma in 3 year olds decreased somewhat with 4,000 IU during pregnancy – RCT Jan 2016
- Overview Asthma and Vitamin D
- Vitamin D Deficiency is a Strong Predictor (4X) of Asthma in Children – Oct 2012
- Asthma reduced 60 percent with vitamin D supplementation – meta-analysis 2014, 2015
- Asthma reduced by weekly 50,000 IU of vitamin D – RCT Aug 2014
- Asthma attacks reduced in half if Vitamin D level higher than 42 nanograms – RCT May 2014
Observational and mechanistic data suggest a role for vitamin D in childhood asthma. However, subsequent interventional trials have been inconsistent. We aimed to assess the effect of 15 weeks of vitamin D3 supplementation compared to placebo in Irish asthmatic children.
We conducted a double-blind, randomized, placebo-controlled trial of vitamin D supplementation (2,000IU/d) in 44 urban, Caucasian children at high latitude. Assessments were completed at baseline and after 15 weeks of supplementation. Outcome measures lung function, subjective asthma control and biochemical parameters of total vitamin D, allergy, immunity, airway inflammation and systemic inflammation. Finally, parents/guardians completed a weekly diary during the trial.
There was no significant difference in baseline 25(OH)D levels but there was a significant increase in median 25(OH)D in the vitamin D3 group (57.5 to 105nmol/L) compared to the placebo group (52.5 to 57.5nmol/L) (p <0.0001). There was no significant difference between groups regarding subjective asthma control. Compared to placebo, there was as a significant decrease in school days missed due to asthma (1 vs. 5 days, p = 0.04) and alkaline phosphatase (-3.4 vs. +16; p = 0.037) in the vitamin D3 group but there were no beneficial effects regarding several other secondary endpoints. However, there were non-significant, advantageous changes in the placebo group compared to the vitamin D3 group in subjective asthma control and lung function, particularly percentage of predicted forced expiratory volume in 1 second (+2.5 vs. -4; p = 0.06).
Vitamin D3 supplementation led to a significant increase in serum 25(OH)D and decreased school days missed (p = 0.04) but no other advantageous changes in asthma parameters compared to placebo. The potential adverse effect of vitamin D deficiency on growth and the potential negative effect of high serum 25(OH)D on pulmonary function warrant further investigation.