TABLE 2 Adult airway obstruction#, forced expiratory volume in 1 s (FEV1) at baseline and FEV1 change by smoking status and asthma
TotalNever-smokersFormer smokersCurrent smokers
Adult airway obstruction n (%)
 No asthma209 (1.0)33 (0.4)42 (0.9)134 (1.8)
 Early-onset asthma138 (10.1)59 (8.8)36 (12.2)43 (10.7)
 Late-onset asthma162 (8.3)57 (6.2)35 (7.6)70 (12.3)
 Total509 (2.1)149 (1.5)113 (2.1)247 (3.0)
Baseline FEV1 L
 No asthma3.77±0.83.78±0.93.80±0.83.75±0.8
 Early-onset asthma3.61±0.93.63±0.93.52±0.83.62±0.8
 Late-onset asthma3.34±0.83.38±0.93.38±0.83.24±0.8
FEV1 change mL·year−1
 No asthma−28.72±32.42−27.05±31.47−28.62±30.44−31.04±35.13
 Early-onset asthma−29.49±44.39−30.97±44.06−24.85±42.57−31.92±47.25
 Late-onset asthma−28.55±41.96−28.52±40.69−27.05±40.95−30.18±45.42
  • Data are presented as mean±sd unless otherwise stated. #: 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; measurements from both surveys are used, thus one individual may contribute with two measurements. : FEV1 in the ECRHS II minus FEV1 in ECRHS I.