a survey of international trial results.
A comparison of data from seven trials involving 435 children and two trials involving 658 adults from the United States, Britain, Canada, India, Japan and Poland showed that vitamin D reduced the risk of an acute attack requiring a hospital visit from 6 percent to around 3 percent.
“This is an exciting result, but some caution is warranted,” cautioned Adrian Martineau, a professor of respiratory infection at Queen Mary University of London who led the study.
Benefits for all or some?
Researchers are still investigating whether benefits for exacerbation prevention are experienced by everyone, or only by people with lower vitamin D levels.
“We are doing individual patient data meta-analysis to answer this question,” Martineau told Allergic Living. “Once results are in, we would recommend taking vitamin D tablet supplements.”
The study review revealed that vitamin D supplements reduced the rate of asthma attacks severe enough to require treatment with steroid tablets. It also found that vitamin D did not improve lung function or day-to-day asthma symptoms.
Most study participants had mild to moderate asthma, and a minority had severe asthma. Most continued to take their usual asthma medication while participating in the studies, which lasted between six and 12 months.
Interest in the potential role of vitamin D in asthma management has increased because due to indications it might help reduce such upper respiratory infections as the common cold that can worsen asthma.
Asthma affects about 300 million people worldwide and can cause wheezing, coughing, chest tightness and shortness of breath.