Do asthmatic smokers benefit as much as non-smokers on budesonide/formoterol maintenance and reliever therapy? Results of an open label study

Abstract

Background: Studies with inhaled corticosteroids (ICS) in smoking asthmatics have mostly shown poorer treatment responses than in non-smoking asthmatics.

Methods: EuroSMART, an open, randomised, 6-month study, compared budesonide/formoterol (Symbicort (®) Turbuhaler(®))(h) maintenance and reliever therapy (Symbicort SMART(®)) at two maintenance doses of budesonide/formoterol (160/4.5 μg), 1 × 2 and 2 × 2, in patients with asthma who were symptomatic despite treatment with ICS ± long-acting β(2)-agonists. The 8424 randomised patients included 886 smokers (11%; aged <40 years or with a smoking history <10 pack-years if older), who were compared with a propensity-matched group of non-smokers. At baseline, smokers had lower post-bronchodilator peak expiratory flow, lower peak flow reversibility and used more reliever medication per day. Severe asthma exacerbations were counted and changes in five-item Asthma Control Questionnaire (ACQ-5) scores from baseline calculated.

Results: There were 48 and 47 exacerbations in smokers and non-smokers, respectively. Mean time to first severe exacerbation was not statistically different between the two groups. The mean change in ACQ-5 score was significantly greater in non-smokers. Considering the two treatment options there was a statistically significant prolonged time to first severe exacerbation with 2 × 2 versus 1 × 2 in the smokers, but not in the non-smokers. In smokers, the reductions in ACQ-5 scores, asthma symptoms, use of as-needed medication and awakenings were also all significant in favour of 2 × 2 with similar or greater changes than in smokers treated with 1 × 2.

Conclusion: Asthmatic patients with a limited smoking history benefit from treatment with budesonide/formoterol maintenance and reliever therapy with dosing 2 × 2 being superior to 1 × 2.