Vitamin D Could Reduce Severe Asthma Attacks

Humans naturally produce vitamin D from exposure to sunlight and can also consume it in various foods, including fish and eggs. Many individuals also choose to take supplements to ensure they are reaping the benefits of vitamin D.

The results of a new study presented at the European Respiratory Society’s International Congress suggest that vitamin D supplementation plus standard asthma therapy will reduce the prevalence of severe asthma attacks.

Asthma affects more than 300 million individuals and is characterized by wheezing, coughing, chest tightness, and shortness of breath. Low levels of vitamin D have been known to increase the risk of asthma attacks.

The authors report that vitamin D may reduce upper respiratory infections that can cause asthma symptoms to flare up. Multiple clinical trials have explored whether vitamin D supplements impact asthma attacks, symptoms, and lung function.

Included in the new study were 7 trials including 435 children and 2 trials involving 658 adult patients from around the world. A majority of participants had mild-to-moderate asthma, with a few having severe asthma.

The authors found that vitamin D supplements reduced the risk of asthma attacks that required hospitalization or an emergency department visit from 6% to 3%, according to the study.

Taking vitamin D supplements was also found to lower the occurrence of asthma attacks that require steroid treatment.

The authors did not find any increased risk of side effects with the implementation of the supplements, suggesting it may be a beneficial treatment.

"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,” said lead author Adrian Martineau, PhD.

However, vitamin D supplements did not result in improved lung function or relieve symptoms, according to the study. These findings may indicate that the supplements may only stave off serious attacks rather than improve symptoms.

"This is an exciting result, but some caution is warranted,” Dr Martineau said. “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. Second, 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 analyses to investigate these questions are on-going, and results should be available in the next few months."