Table 1 Characteristics of study groups at baseline and length of follow-up periods
From: Does lung function predict the risk of disability pension? An 11-year register-based follow-up study
Obstructive spirometry n = 111 | Restrictive spirometry n = 95 | Controls n = 3180 | All n = 3386 | |
|---|---|---|---|---|
Age,mean years, (SD) | 45.9 (7.8) | 46.2 (8.4) | 44.2 (8.3) | 44.3 (8.3) |
Males | 57 (51%) | 60 (63%) | 1550 (49%) | 1667 (49%) |
Education | ||||
Basic | 36 (32%) | 35 (37%) | 686 (22%) | 757 (22%) |
Mid-level | 35 (32%) | 41 (43%) | 1219 (38%) | 1295 (38%) |
University | 40 (36%) | 19 (20%) | 1275 (40%) | 1334 (39%) |
Doctor-diagnosed asthma | 25 (23%) | 11 (12%) | 187 (6%) | 223 (7%) |
Self-reported COPD | 8 (7%) | 1 (1%) | 10 (0.3%) | 19 (1%) |
Smoking | ||||
non-smoker | 30 (27%) | 33 (35%) | 1557 (49%) | 1620 (48%) |
ex-smoker | 24 (22%) | 25 (26%) | 646 (20%) | 695 (21%) |
current smoker | 57 (51%) | 37 (39%) | 976 (31%) | 1070 (32%) |
S-cotinine ≥ 100μg/l | 59 (53%) | 33 (35%) | 826 (26%) | 918 (27%) |
BMI | ||||
< 25 | 61 (55%) | 18 (19%) | 1332 (42%) | 1411 (42%) |
25–29.9 | 37 (33%) | 30 (32%) | 1280 (40%) | 1347 (40%) |
≥ 30 | 13 (12%) | 47 (50%) | 567 (18%) | 627 (19%) |
FEV1% predicted | ||||
FEV1 ≥ 80% | 0 (0%) | 70 (74%) | 1996 (63%) | 2066 (61%) |
50 ≤ FEV1 < 80 | 109 (98%) | 25 (26%) | 1184 (37%) | 1318 (39%) |
30 ≤ FEV1 < 50 | 2 (2%) | 0 (0%) | 0 (0%) | 2 (0.1%) |
FEV1 < 30 | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) |
Length of follow-up period, mean years (SD) | 9.4 (3.0) | 8.7 (3.5) | 9.7 (2.8) | 9.7 (2.8) |
Co-morbidities | ||||
1 | 37 (33%) | 29 (31%) | 1032 (33%) | 1098 (32%) |
≥ 2 | 25 (23%) | 24 (25%) | 476 (15%) | 525 (16%) |
Physically active | 66 (60%) | 45 (48%) | 1775 (56%) | 1886 (56%) |