(RxWiki News) Asthma can worsen as warmer weather produces more irritating pollens. It’s previously been suggested that vitamin D supplements might relieve asthma symptoms and prevent attacks, but that may not be true.
According to a new study, adults with asthma who were given vitamin D3, along with their normal prescription medications for treating the disease, did not find that their symptoms improved.
"Ask your doctor about curbing asthma symptoms."
This new study’s lead author was Tonya King, PhD, of Penn State College of Medicine in Hershey, PA.
For this investigation, Dr. King and her research team reviewed the medical effects of roughly dividing 408 adults with asthma into two groups, then giving one group high-dose vitamin D3 and giving the other a placebo containing no vitamin D3. All these asthma patients already were using corticosteroid inhalers.
The 408 adults had been enrolled in the VIDA (Vitamin D Add-on Therapy Enhances Corticosteroid Responsiveness in Asthma) trial, a clinical trial that the National Heart, Lung and Blood Institute’s Asthma Network conducted at nine sites across that United States.
Over 28 weeks of the clinical trial, patients continued to take their inhaled corticosteroid medicines. The inhaler use was decreased after the first 12 weeks. Patients were monitored to determine whether adding vitamin D3 or the placebo to their inhalers reduced asthma symptoms, including the severe attacks that can cause them to gasp for breath.
Taking vitamin D3 did not significantly reduce asthma symptoms, these researchers concluded. Of the patients taking vitamin D3, 29 percent had an asthma attack during the 28 weeks, and 28 percent of those taking placebo had an asthma attack.
However, taking vitamin D3 did allow for a slight reduction in the amount of the corticosteroid ciclesonide (Alvesco, Omnaris nasal sprays) that patients were prescribed to keep their asthma from worsening.
"This small effect of add-on vitamin D3 might be important over time, but would require further investigation," the researchers wrote.
Corticosteroids are effective, but not for everyone, the researchers added. About 45 percent of people with asthma tend not to significantly improve by using corticosteroids alone, they wrote. Consequently, many of those patients also are treated with bronchodilators, which relax the lungs' muscles to expand the airways. But the side effects of bronchodilators can include increased heart rate, headache, anxiety and bodily shaking. Further investigation of add-on vitamin D3 is especially important for those using bronchodilators.
Patients with asthma experience shortness of breath of ranging severity, wheezing, coughing and tightness in their chest that results from lung swelling that causes the airways to narrow.
According to the latest available government data, roughly 8 percent of all adults in the United States have asthma. That’s 18.7 million individuals. About half of them had at least one asthma attack in 2008, the latest year for which the US Centers for Disease Control and Prevention (CDC) has calculated that statistic.
Asthma is a chronic disease that has no cure. In addition to following a physician's prescribed care plan — including medicines for long-term maintenance and to handle short-term, emergency asthma attacks — people with asthma are encouraged to stay physically active. That activity helps the lungs to function at their optimum level.
This study was published online May 27 in JAMA.
The National Institutes of Health funded the study.
Several of the researchers disclosed receiving grants from the National Heart, Lung and Blood Institute, several pharmaceutical corporations and other organizations.