PURPOSE OF THE STUDY.
To assess whether low-dose, short-term vitamin D supplementation in addition to standard treatment improved control of childhood asthma.
Eighty-nine Japanese schoolchildren ages 6–15 years who had a diagnosis of asthma based on GINA criteria and spirometry were randomly assigned to receive vitamin D (n = 54) or a placebo (n = 35). Ninety-four percent of subjects were using either an inhaled corticosteroid or a leukotriene receptor antagonist at baseline. The median vitamin D level at baseline was 29 ng/mL.
Collaborating pediatricians who examined the subjects at baseline, 2 months, and 6 months were blinded to vitamin D3 (800 IU/day) or placebo treatment throughout the study. Subjects were assessed for asthma control as the primary outcome by GINA guidelines at these time points. Adherence to treatment was evaluated. Levels of serum 25(OH)D, serum IgE, and selected allergen-specific IgE levels were measured.
At 2 months, asthma control by GINA guidelines was significantly improved in the vitamin D group compared with the placebo group (P = .015). Childhood asthma control test (CACT) scores (a secondary outcome) were similarly improved at 2 months (P = .004) and 6 months (P = .012) in the vitamin D group versus the placebo group. Fewer subjects in the vitamin D group (15%) had a peak expiratory flow rate of <80% compared with the placebo group (34%) at 6 months (P = .032).
Low-dose, short-term vitamin D supplementation in addition to standard treatment may improve levels of asthma control in schoolchildren.
There are contrasting studies in the area of vitamin D supplementation and asthma. The strengths/novelty of this study are as follows: (1) it is a randomized, double-blind, placebo-controlled trial; (2) it involves children who are on controller therapies; and (3) it includes subjects who are not as deficient in vitamin D as those in other studies. The results support further investigation in this area to examine different doses and durations of vitamin D supplementation and the potential seasonal benefit in controlling asthma.
- Copyright © 2017 by the American Academy of Pediatrics