Vitamin D3 did not reduce the rate of first treatment failure or exacerbation in adults with persistent asthma and vitamin D insufficiency.

In asthma and other diseases, vitamin D insufficiency is associated with adverse outcomes. It is not known if supplementing inhaled corticosteroids with oral vitamin D3 improves outcomes in patients with asthma and vitamin D insufficiency.

Researchers aimed to evaluate if vitamin D supplementation would improve the clinical efficacy of inhaled corticosteroids in patients with symptomatic asthma and lower vitamin D levels.

Treatment with vitamin D3 did not alter the rate of first treatment failure during 28 weeks (28% [95% CI, 21%-34%] with vitamin D3 vs 29% [95% CI, 23%-35%] with placebo; adjusted hazard ratio, 0.9 [95% CI, 0.6-1.3]).

Of 14 pre-specified secondary outcomes, 9 were analyzed, including asthma exacerbation. Of those 9, the only statistically significant outcome was a small difference in the overall dose of ciclesonide required to maintain asthma control.

According to researchers writing in JAMA, results did not support a strategy of therapeutic vitamin D3 supplementation in patients with symptomatic asthma.