Vitamin D Supplements Could Reduce Severe Asthma Attacks

06 Sep 2016 --- Results from new randomized trials have shown that taking an oral vitamin D supplement in addition to standard asthma medication could help to reduce severe asthma attacks. The study, named the Cochrane Review, follows previous research into how low levels of vitamin D could be linked to increased risk of asthma attacks in children and adults with asthma.

The team of Cochrane researchers found seven trials involving 435 children and two studies, involving 658 adults. The study participants were ethnically diverse, reflecting the broad range of global geographic settings, involving Canada, India, Japan, Poland, the UK, and the U.S. 

The majority of participants that took part in the studies had mild to moderate asthma, while a minority suffered with severe symptoms of the condition. Most people continued to take their usual asthma medication while participating in the studies.

The studies lasted for between six and 12 months, and the results showed that by giving participants an oral vitamin D supplement, they reduced their risk of severe asthma attacks requiring hospital admission or emergency department attendance from 6% to around 3%.

The researchers also found that vitamin D supplementation reduced the rate of asthma attacks needing treatment with steroid tablets, although these results were based largely on trials in adults.

However, despite the study showing that supplementing with vitamin D resulted in a reduced rate of asthma attacks, it also revealed that day-to-day asthma symptoms or overall lung function were not effected.

The Cochrane Review’s lead author, Professor Adrian Martineau from the Asthma UK Centre for Applied Research, Queen Mary University of London, said: “We found that taking a vitamin D supplement in addition to standard asthma treatment significantly reduced the risk of severe asthma attached, without causing side effects.” 

He added: “This is an exciting result, but some caution is warranted. First, the findings relating to severe asthma attacks come from just three trials. Most of the patients enrolled in these studies were adults with mild or moderate asthma. Further vitamin D trials in children and in adults with severe asthma are needed to find out whether these patient groups will also benefit.”

“Secondly,” Martineau continued, “It is not yet clear whether vitamin D supplements can reduce risk of severe asthma attacks in all patients, or whether this effect is just seen in those who have low vitamin D levels to start with. Further analyzes to investigate this questions are on-going, and results should be available in the next few months."