A recently published multi-center study found that supplemental vitamin D did not help patients with low vitamin D blood levels and symptomatic asthma. The trial, funded by the National Heart Lung and Blood Institute, failed to demonstrate any benefit of vitamin D on the primary measure – time to first treatment failure – or on eight of nine secondary measures.

“These findings do not support a strategy of therapeutic Vitamin D3 supplementation in patients with symptomatic asthma,” wrote the authors, who included Richard Martin, MD, chair of medicine at National Jewish Health, and Michael Wechsler, MD, director of the asthma program at National Jewish Health.

Earlier studies had associated low vitamin D blood levels with more asthma symptoms and medication use, and with reduced response to the mainstay asthma medication, inhaled corticosteroids.

The Vitamin D Add-on Therapy Enhances Corticosteroid Responsiveness in Asthma (VIDA) trial was conducted at nine academic medical centers participating in the NHLBI’s AsthmaNet clinical research network. It randomized 408 adults with low vitamin D and mild/moderate asthma to receive the inhaled corticosteroid ciclesonide supplemented with either high-dose vitamin D3 or placebo. Participants were then monitored over 28 weeks for the occurrence of worsening asthma.

Vitamin D3 supplementation did not reduce the proportion of participants who experienced at least one treatment failure (28 percent vs. 29 percent in placebo) or one exacerbation (13 percent vs. 19 percent) nor the overall exacerbation rate. More of the vitamin D treated patients were able to reduce their inhaled steroid dose by 75 percent compared to those treated with placebo (89 percent vs. 80 percent).

The findings were presented on May 18, 2014, at the American Thoracic Society annual meeting and concurrently published in the Journal of the American Medical Association.

Dr. Katherine Bloom of Allergy & Asthma Care of Fairfield County comments: “Much has been learned about the benefits of vitamin D over the past several years. There has been some preliminary evidence that vitamin D supplementation might benefit asthma patients, but this well-constructed study demonstrates minimal effect. More studies need to be performed, but at this time, we cannot recommend vitamin D supplementation in the treatment of asthma.”