Vitamin D shines in review of asthma management
An international asthma review involving University of Newcastle (UON) researcher Dr Megan Jensen has found that Vitamin D supplements can reduce the need for corticosteroid treatment and hospital visits.
Dr Jensen, an accredited practising dietitian from HMRI’s VIVA program and UON GrowUp Well research centre, conducted a pilot trial with pre-schoolers during a two-year appointment to Montreal, Canada. Children with asthma were given 2ml of Vitamin D in a cherry-flavoured liquid supplement at the start of winter, while others took a placebo.
“The study involved a small group of 22 children and was really designed to show the feasibility of administering the dose, following the children up over six months and collecting blood samples to ensure there were no adverse effects,” Dr Jensen explained.
“The increase in asthma exacerbations during the Canadian winter coincides with the reduced exposure to sunlight, the primary source of Vitamin D. There’s evidence that the vitamin boosts the immune system and helps ward off viral infections like the common cold, which are a common trigger for asthma.”
Dr Jensen’s data was pooled with eight other studies of children and adults for the comprehensive Cochrane Review, which was presented at the European Respiratory Society Congress in London this week.
Overall figures showed that the oral vitamin D supplement, taken in addition to standard asthma management, lowered the risk of severe asthma attacks requiring hospital admission from 6 per cent to around 3 per cent.
It also significantly reduced the need for medication in response to moderate to severe attacks, with no side effects found. However, Vitamin D had little effect on lung function or day-to-day asthma symptoms.
Dr Jensen adds that further trials are needed to determine if the effects of supplements are greater in people who have lower baseline levels of Vitamin D. A larger multicentre trial, expanded from her pilot trial in pre-schoolers, is currently underway in Canada.
“I would say at this point that people with asthma should keep a good check on overall nutrition, including Vitamin D. You can get Vitamin D through foods like salmon, eggs and also fortified products like yoghurt, milk and margarine, as well as safe levels of sunlight exposure.”
* The Cochrane Review study is available at http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD011511.pub2/full. Dr Megan Jensen is from the University of Newcastle, researching with HMRI’s Viruses, Infections/Immunity, Vaccines and Asthma program. HMRI is a partnership between the University of Newcastle, Hunter New England Health and the community.