TABLE 3 Adjusted associations of asthma and smoking status with adult airway obstruction# and forced expiratory volume in 1 s (FEV1) change
Adult airway obstructionFEV1 change per year
Subjects %OR (95% CI)Mean change+ mL·year−1Adjusted difference+ mL (95% CI)
No asthma
 Never-smokers0.31.00−25.790
 Current smokers1.54.54 (2.95–6.99)−32.15−6.35 (−8.21– −4.50)
Early-onset asthma
 Never-smokers6.921.01 (12.67–34.94)−33.47−7.68 (−12.18– −3.17)
 Current smokers7.823.72 (13.86–40.58)−38.57−12.78 (−19.14– −6.43)
Late-onset asthma
 Never-smokers3.711.21 (6.75–18.60)−29.59−3.80 (−7.49– −0.11)
 Current smokers8.425.60 (15.64–41.90)−33.96−8.17 (−13.07– −3.27)
  • #: pre-bronchodilator FEV1/forced vital capacity ratio <70% and FEV1 <80% predicted measured either at the European Community Respiratory Health Survey (ECRHS) I or II; : from generalised estimation equation models, adjusted for sample, age, sex, height, country and education; +: from mixed-effect linear regression, adjusted for FEV1 at baseline, education, age, height, body mass index (BMI) change, BMI, sample, sex and country.