TABLE 1 Cohort characteristics at baseline by adult airway obstruction#
Adult airway obstructionTotal
NoYes
Total15 243 (100.0)425 (100.0)15 668 (100.0)
Age
 <30 years5320 (34.9)93 (21.9)5413 (34.6)
 30–38 years5041 (33.1)138 (32.5)5179 (33.1)
 ≥38 years4879 (32.0)194 (45.6)5073 (32.4)
Age years33.7 (27.6–39.9)37.2 (30.9–42.1)33.8 (27.6–40.0)
Age at follow-up years43.1 (37.0–49.0)46.3 (40.6–51.2)43.2 (37.1–49.1)
Sex
 Males7413 (48.6)247 (58.1)7660 (48.9)
 Females7830 (51.4)178 (41.9)8008 (51.1)
Asthma
 No13 301 (87.6)192 (45.7)13 493 (86.4)
 Early onset796 (5.2)110 (26.2)906 (5.8)
 Late onset+1092 (7.2)118 (28.1)1210 (7.8)
Smoking
 Never6454 (43.0)127 (30.7)6581 (42.7)
 Former3114 (20.7)73 (17.6)3187 (20.7)
 Current
  0–10 pack-years2382 (15.9)49 (11.8)2431 (15.8)
  10–20 pack-years1634 (10.9)57 (13.8)1691 (11.0)
  >20 pack-years1426 (9.5)108 (26.1)1534 (9.9)
Atopy§4532 (33.8)206 (54.6)4738 (34.3)
Age on completing education
 >22 years3741 (26.3)86 (22.5)3827 (26.2)
 18–22 years4366 (30.7)83 (21.7)4449 (30.5)
 ≤18 years6105 (43.0)214 (55.9)6319 (43.3)
Childhood factors
 Maternal asthma1013 (6.9)49 (12.2)1062 (7.0)
 Paternal asthma896 (6.3)72 (18.4)968 (6.6)
 Paternal atopy2086 (15.2)76 (20.2)2162 (15.3)
 Maternal atopy3049 (21.5)76 (19.8)3125 (21.5)
 Infection <5 years of age1554 (10.9)82 (21.4)1636 (11.1)
 Maternal smoking3822 (25.4)129 (31.4)3951 (25.6)
Country
 Australia715 (4.7)42 (9.9)757 (4.8)
 Belgium787 (5.2)22 (5.2)809 (5.2)
 Estonia476 (3.1)9 (2.1)485 (3.1)
 France2076 (13.6)40 (9.4)2116 (13.5)
 Germany1673 (11.0)28 (6.6)1701 (10.9)
 Iceland592 (3.9)17 (4.0)609 (3.9)
 Italy897 (5.9)13 (3.1)910 (5.8)
 The Netherlands387 (2.5)4 (0.9)391 (2.5)
 Norway751 (4.9)22 (5.2)773 (4.9)
 Spain2105 (13.8)69 (16.2)2174 (13.9)
 Sweden2057 (13.5)37 (8.7)2094 (13.4)
 Switzerland907 (6.0)38 (8.9)945 (6.0)
 UK1380 (9.1)76 (17.9)1456 (9.3)
 USA440 (2.9)8 (1.9)448 (2.9)
Participation in ECRHS
 Only ECRHS I7044 (46.2)171 (40.2)7215 (46.0)
 Both ECRHS I and II8199 (53.8)254 (59.8)8453 (54.0)
  • Data are presented as n (%) or median (interquartile range). ECRHS: European Community Respiratory Health Survey. #: pre-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity ratio <70% and FEV1 <80% predicted measured either at the ECRHS I or II; : <10 years of age; +: >10 years of age; §: assay result >0.35 kU·L−1 for house dust mite, timothy grass, cat dander or moulds.