An international study into asthma treatment is a "game changer" for hundreds of thousands of Kiwis who live with the breathing conditions, a New Zealand researcher says.

Inhaler devices for treating asthma contain either a medicine designed to prevent or relieve symptoms - or both in the one device.

At least 12 per cent of New Zealanders - around 600,000 people - have asthma, which causes wheezing and other breathing problems. The majority experience mild symptoms.

The New Zealand-led study of mild asthma in adults found that patients instructed to use the Symbicort combination medication "as needed" had half as many asthma episodes of breathing difficulties - called "exacerbations" - as those using a Ventolin reliever.


They also had 56 per cent fewer severe exacerbations than those using just the reliever; and 60 per cent fewer than those using two inhalers - a Pulmicort preventer twice a day plus puffs as-needed from a Ventolin reliever.

"The findings from the study are exciting and have the potential to be a game changer in the way doctors treat mild asthma," said Wellington researcher Professor Richard Beasley, the first author on the four-country study published in the United States today in the prestigious New England Journal of Medicine.

The trial included patients from New Zealand, Australia, Britain and Italy whose only asthma therapy in the preceding three months was a short-acting reliever inhaler.

The researchers said the current practice with mild asthma was to prescribe a preventer containing corticosteroid for twice-daily use, and a reliever to dilate the breathing tubes to help fix wheezing and other symptoms.

But many doctors were reluctant to prescribe preventers and patients were unlikely to use them regularly if their symptoms were infrequent.

Beasley said the trial showed that those on the as-needed combined inhaler "do a lot better" than those on the regimen advocated by current guidelines.

"The greater benefit was achieved despite exposure to less than half the amount of inhaled corticosteroid preventer medication because the inhaled corticosteroid works better when taken as needed in mild asthma.

"This novel approach simplifies treatment as it doesn't require patients to take a preventer inhaler twice daily even when they have no symptoms."


"With a combined preventer-reliever inhaler, patients have more personal and immediate control over their asthma management. This takes advantage of the patient's natural behaviour to take a reliever only when they are experiencing symptoms."

Asthma and Respiratory Foundation medical director Dr Stuart Jones, a respiratory physician, said the Beasley study would lead to a re-think of the New Zealand guidelines on the management of mild asthma.

"For those with mild asthma, implementation of the study's findings will lead to a reduction in exacerbations, which means less time feeling unwell and more time doing what you enjoy in life, all while using inhaled steroids sparingly."

He said Symbicort is state-funded in New Zealand but some people struggled to use the device. Another, called Vannair, which contained the same medications, was also funded but had only been registered here for regular use, not for as-needed use.

The trial received research grants from the company that supplies Symbicort and Pulmicort, AstraZeneca, and from the Health Research Council of New Zealand.

An asthma patient


Sarah Harris, 39, a laundromat installer and mother of two, of Kingseat, south of the Manukau Harbour, has had mild asthma since she was pregnant with son Cole, who is now 14.

"I caught pneumonia when I was pregnant with my son when I was 24. I got asthma then and it never went away."

Cole and Sarah's husband, Conan, also have the breathing disorder.

"I don't get it very often," Harris said. "Some days I'm just short of breath or it's harder to get around."

Hospital treatment had never been required.

She uses Flixotide inhaled corticosteroid preventer medication twice a day, and occasionally also a Ventolin reliever inhaler. The Ventolin sees more regular use, however, when she catches a cold. And around once a year she needs stronger treatment.


"If it's really bad, I just can't do anything and I usually end up with prednisone [oral steroid medicine]."

Cole had been prescribed a Symbicort combination medication inhaler, two doses a day, and Sarah was interested in the study's findings on using that type of inhaler on an as-needed basis to treat mild asthma.

"That would be helpful for a lot of people," she said.