Vitamin D protects against severe asthma attacks

October 3, 2017, Queen Mary, University of London
Credit: CC0 Public Domain

Taking oral vitamin D supplements in addition to standard asthma medication could halve the risk of asthma attacks requiring hospital attendance, according to research led by Queen Mary University of London (QMUL).

Asthma affects more than 300 million people worldwide and is estimated to cause almost 400,000 deaths annually. Asthma deaths arise primarily during episodes of acute worsening of symptoms, known as attacks or 'exacerbations', which are commonly triggered by viral .

Vitamin D is thought to protect against such attacks by boosting immune responses to respiratory viruses and dampening down harmful airway inflammation.

The new study, funded by the National Institute for Health Research, and published in The Lancet Respiratory Medicine, collated and analysed the individual data from 955 participants in seven randomised controlled trials, which tested the use of vitamin D supplements.

Overall, the researchers found that vitamin D supplementation resulted in:

  • a 30 per cent reduction in the rate of attacks requiring treatment with steroid tablets or injections - from 0.43 events per person per year to 0.30.
  • a 50 per cent reduction in the risk of experiencing at least one requiring Accident and Emergency Department attendance and/or hospitalisation - from 6 per cent of people experiencing such an event to 3 per cent.

Vitamin D supplementation was found to be safe at the doses administered. No instances of excessively high calcium levels or renal stones were seen, and serious adverse events were evenly distributed between participants taking vitamin D and those on placebo.

Lead researcher Professor Adrian Martineau said: "These results add to the ever growing body of evidence that vitamin D can support immune function as well as bone health. On average, three people in the UK die from asthma attacks every day. Vitamin D is safe to take and relatively inexpensive so supplementation represents a potentially cost-effective strategy to reduce this problem."

The team's use of individual participant data also allowed them to query the extent to which different groups respond to vitamin D supplementation, in more detail than previous studies.

In particular, vitamin D supplementation was found to have a strong and statistically-significant protective effect in participants who had low vitamin D levels to start with. These participants saw a 55 per cent reduction in the rate of asthma exacerbations requiring treatment with steroid tablets or injections - from 0.42 events per person per year to 0.19.

However, due to relatively small numbers of patients within sub-groups, the researchers caution that they did not find definitive evidence to show that effects of vitamin D supplementation differ according to baseline D status.

Professor Hywel Williams, Director of the NIHR Health Technology Assessment Programme, said: "The results of this NIHR-funded study brings together evidence from several other studies from over the world and is an important contribution to reducing uncertainties on whether Vitamin D is helpful for asthma - a common condition that impacts on many thousands of people worldwide."

Dr David Jolliffe from QMUL, first author on the paper, added: "Our results are largely based on data from adults with mild to moderate asthma: children and adults with severe asthma were relatively under-represented in the dataset, so our findings cannot necessarily be generalised to these patient groups at this stage. Further clinical trials are on-going internationally, and we hope to include data from them in a future analysis to determine whether the promise of today's results is confirmed in an even larger and more diverse group of patients."

Explore further: High quality evidence suggests vitamin D can reduce asthma attacks

More information: 'Vitamin D supplementation to prevent asthma exacerbations: systematic review and meta-analysis of individual participant data' The Lancet Respiratory Medicine, DOI: 10.1016/S2213-2600(17)30346-6

Related Stories

High quality evidence suggests vitamin D can reduce asthma attacks

September 6, 2016
A new Cochrane Review, published in the Cochrane Library today and presented at the ERS International Congress, has found evidence from randomised trials, that taking an oral vitamin D supplement in addition to standard asthma ...

Vitamin D protects against colds and flu, finds major global study

February 16, 2017
Vitamin D supplements protect against acute respiratory infections including colds and flu, according to a study led by Queen Mary University of London (QMUL).

Vitamin D supplementation doesn't cut colds in asthma

November 18, 2015
(HealthDay)—Vitamin D supplementation does not reduce cold severity or frequency among adults with mild-to-moderate asthma, according to a study published online Nov. 5 in the American Journal of Respiratory and Critical ...

Vitamin D won't guard against colds in people with asthma

December 11, 2015
(HealthDay)—If you have asthma, vitamin D supplements won't protect you against colds, new research suggests.

Vitamin D levels not linked to asthma or dermatitis

May 9, 2017
Vitamin D supplementation is unlikely to reduce the risk of asthma in children or adults, atopic dermatitis, or allergies according to a new study published in PLOS Medicine by Brent Richards, of McGill University, Canada, ...

Vitamin D in pregnancy may prevent childhood asthma

May 26, 2017
A new study published today in the Journal of Allergy and Clinical Immunology has found that taking Vitamin D supplements in pregnancy can positively modify the immune system of the newborn baby, which could help to protect ...

Recommended for you

Living the high life: How altitude influences bone growth

June 19, 2018
High altitude is a particularly challenging environment—the terrain is physically challenging and the land has a relatively poor crop yield, so food can be sparse. Most importantly, oxygen levels are lower meaning that ...

Introduction of alcohol found to adversely impact fertility rates in hunter-gatherer community

June 19, 2018
Fernando Ramirez Rozzi, a research director with the French National Centre for Scientific Research has found that the introduction of alcohol to a Baka pygmy hunter-gatherer society caused fertility rates to fall. In his ...

Risks of cancer and mortality by average lifetime alcohol intake

June 19, 2018
The risk of mortality, and of developing a number of cancers, is lowest in light drinkers consuming an average of less than one drink per day across their lifetime, and the risk of some cancers increases with each additional ...

Bad habits that lead to cancer, chronic disease corrected by simple lifestyle intervention

June 19, 2018
Does this sound like someone you know? He or she spends too much time in front of screens, gets little exercise and eats a diet high in fat and low in fruits and vegetables.

Graphic warning labels linked to reduced sugary drink purchases

June 18, 2018
Warning labels that include photos linking sugary drink consumption with obesity, type 2 diabetes, and tooth decay, may reduce purchases of the drinks, according to a new study by researchers from Harvard T.H. Chan School ...

Greater levels of vitamin D associated with decreasing risk of breast cancer

June 15, 2018
Researchers at University of California San Diego School of Medicine suggest higher levels of vitamin D are associated with decreasing risk of breast cancer. Their epidemiological study is published in the June 15 online ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.