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Vitamin D3 does not prevent treatment failure in asthmatic adults with low vitamin D levels

Clinical Question:
Does high-dose vitamin D3 help prevent treatment failure or exacerbation in asthmatic adults with low vitamin D levels?

Bottom Line:
This study found that adding high-dose vitamin D3 to standard asthma treatment (including inhaled corticosteroids and beta2-agonists) in adults with symptomatic asthma and low vitamin D levels does not prevent treatment failure or exacerbation. (LOE = 1b)

Castro M, King TS, Kunselman SJ, et al, for the National Heart, Lung, and Blood Institute’s AsthmaNet. Effect of vitamin D3 on asthma treatment failures in adults with symptomatic asthma and lower vitamin D levels. The VIDA randomized clinical trial. JAMA 2014; 311(20):2083-2091.  [PMID:24838406]

Study Design:
Randomized controlled trial (double-blinded)



Outpatient (any)

These investigators enrolled 1068 adults, 18 years or older, who met standard diagnostic criteria for asthma and had a serum 25-hydroxyvitamin D level of less than 30 ng/mL. During an initial run-in period all patients received at least 2 weeks of treatment with ciclesonide and levalbuterol. Patients with mild or severe symptoms were excluded and the remaining participants (n = 408) randomly received (concealed allocation assignment) either high-dose vitamin D3 (100,000 IU once, followed by 4000 IU daily) or matched placebo. The investigators defined treatment failure and exacerbation using the following criteria: increased use of levalbuterol or inhaled corticosteroid, need for systemic steroids (oral or parenteral), patient satisfaction, and/or physician clinical judgment. Patients and all clinical personnel remained masked to treatment group assignment. Complete follow up occurred for 88% of patients for a median duration of 28.1 weeks. Using intention-to-treat analysis, no significant differences in time to first treatment failure or to first exacerbation occurred between the 2 groups. Patients in the high-dose vitamin D group tapered their doses of inhaled corticosteroids significantly more than did those in the placebo group, but no differences occurred between the groups for other secondary outcomes, including overall treatment failure or exacerbation rates, asthma control, airway function, quality of life, or airway inflammation. The study was 90% powered to detect a predetermined clinically significant difference in the 2 treatment groups, if one existed. Adverse events also did not significantly differ between the groups. Megan K. Magovern, MD; Faculty Development Fellow, Department of Family Medicine, The University of Virginia, Charlottesville, VA.


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