The Woolcock Institute of Medical Research

Australians with mild asthma can manage their severe asthma exacerbations with a combination inhaler just as effectively as with daily preventer treatment, important new Australian research reveals.

An international study led by the Woolcock Institute of Medical Research in Sydney has found that a new regimen using a combination preventer and reliever medication as needed for relief of symptoms in mild asthma lowers the risk of severe flare-ups after even a single day with modestly higher reliever use.

The results are published in the prestigious Lancet Respiratory Medicine.

“This interesting analysis shows, in patients with mild asthma, that a single day of repeated use of a low-dose combination preventer and reliever inhaler, taken to relieve symptoms, can also protect against severe exacerbations as effectively as if they had been regularly taking traditional preventer medication,” explains lead author and Woolcock asthma specialist Professor Helen Reddel. “We know that in patients with more severe asthma, taking preventer treatment every day is essential to protect them against severe attacks, but this new research challenges previous assumptions that daily treatment is also essential for patients with mild asthma.” 

These findings also suggest that the greater the severe exacerbation risk, the greater the benefit of the as-needed combination inhaler.

More than a million Australians have a mild form of asthma, a chronic lung condition that inflames and narrows the airways, causing wheezing, shortness of breath, chest tightness and coughing. Recently updated national guidelines for adults and adolescents recommend these patients use either a standard preventer inhaler every day, even when they have no symptoms, or a combination preventer and reliever whenever they have symptoms. However, most Australians with mild asthma still rely only on a blue reliever puffer – the ‘ambulance at the bottom of the cliff’ solution – which treats immediate symptoms but leaves patients vulnerable to dangerous asthma attacks. 

“People with apparently mild asthma sadly make up 20 per cent of adults who die of asthma,” Dr Reddel says. “That’s largely because they aren’t getting the right treatment.”

The Woolcock specialist worked with researchers in Canada, South Africa, England, China and Sweden to conduct randomised controlled trials with the combination inhaler, marketed as Symbicort Turbuhaler. In one of these studies published in the NEJMed, almost 4000 patients with mild asthma were randomised to use either as-needed low dose Symbicort, as needed traditional reliever puffer, or daily preventer plus as-needed reliever.

In this new analysis, the team assessed the short-term risk of a severe exacerbation in the 21 days after a single day of extra reliever inhalations. “Our analysis showed that although patients with mild asthma used reliever, on average, on less than one-third of days, they did experience occasional days of higher reliever use, especially if they were using a blue reliever inhaler alone,” Professor Reddel says. “Importantly, even a single day with increased reliever-only use was associated with an increased short-term risk of severe exacerbations.”

And in the event of a single day of even modestly higher reliever use, as-needed low dose Symbicort inhaler significantly reduced the risk for a severe exacerbation developing in the following 21 days versus reliever alone, with a similar reduction as seen with high adherence to regular preventer inhaler use, she said.

The results highlight a need to change the way we think about mild asthma. “Recently updated Australian asthma guidelines stress the importance of thinking not only about controlling symptoms but also about reducing the risk of severe attacks, including in patients with mild asthma. The worst option is managing asthma only with a blue reliever inhaler. The new guidelines recommend two effective treatment options that patients with mild asthma can discuss with their GP” Dr Reddel says.

The international studies were fully funded by AstraZeneca, the manufacturer of both Symbicort and the preventer medication Pulmicort, but the trials were initiated in response to repeated requests from a small group of leading respiratory experts, including Professor Reddel, for better treatment solutions for patients with mild asthma.

The paper is titled, Effect of a single day of increased as-needed budesonide/formoterol use on short- term risk of severe exacerbations in patients with mild asthma: A post hoc analysis of the SYGMA 1 study