Abstract
Background: The effect of smoking on the long-term decline in lung function in adult-onset asthma is not known.
Aims and Objectives: To evaluate the effect of smoked pack-years on lung function decline in a 12-year follow-up as a part of Seinäjoki Adult-onset Asthma Study (SAAS).
Methods: Patients (n=257) were diagnosed to have new-onset adult asthma during 2000-2002. At the time of diagnosis smoking history was assessed. After 12 years (2012-2013) patients (n=203) were evaluated for lung function and smoking status. Patients were divided into two groups based on smoked pack-years: ≤ 10 and >10. The changes in pre-bronchodilator spirometry values were evaluated. Measurement points were: baseline (i.e. time of diagnosis), the maximum lung function (Max0-2.5) during first 2.5 years after diagnosis (i.e. start of therapy), and after 12 years of follow-up. Differences between groups were compared with student's t-test or Mann-Whitney U-test.
Results: History of smoked pack-years did not significantly affect the change in lung function between baseline and Max0-2.5after diagnosis. In contrast, the annual decline in lung function between Max0-2.5 and 12 years was more rapid among patients with >10 pack-years (table 1).
Annual change in lung function between Max0-2.5 and 12 years from diagnosis
Conclusion: In patients with adult-onset asthma the decline in lung function is more rapid if smoking history exceeds 10 pack-years.
- Copyright ©ERS 2015
