Impact of age, age at diagnosis and duration of asthma on the risk of exacerbations in the EuroSMART study

Background. Information about the influence of age and duration of asthma are limited. Methods. EuroSMART, an open, randomised 6-month study (NCT00463866), compared two maintenance doses of budesonide/formoterol (BUD/FORM) (Symbicort SMART® Turbuhaler®), 160/4.5 μg 1x2 and 2x2, plus as-needed BUD/FORM, in asthmatics ≥18 y with symptoms when treated with ICS±LABA. Mean age of patients was 48 y, (range: 18–96 y) and 62% were females. The effects of biological age, age when asthma was first diagnosed, and duration of asthma were assessed. Among 8053 randomised patients, 4402 (54.6%) were >30 y of age when first diagnosed and 3411 (42.3%) had had asthma for >15 y. Data on allergic status (rhinitis, conjunctivitis) were collected. Severe asthma exacerbations were defined as: need for oral steroids for ≥3 days, emergency room treatment or hospitalisation. Results. Presence of the allergic component decreased with increasing age at first asthma diagnosis. Patients >65 y had more exacerbations, and the risk of a first severe exacerbation was increased by 55.3% (p 30 y of age (p=0.0167; HR=1.248; 95% CI: 1.040, 1.477) and more frequent in patients who had had the diagnosis for >15 y (p=0.0021; HR=1.289; 95% CI: 1.107, 1.582). However, there were no differences in time to first exacerbation between the two randomised treatments 1x2 and 2x2 inhalations in any of the above three age measures. Conclusion. Older patients, those with higher age at diagnosis and patients with long-term asthma have more exacerbations but did not show any difference between the 1x2 and 2x2 groups.