Variable | Baseline participants not included in the current study# | Current study sample¶ | p-values+ |
Females % | 50.2 | 52.9 | 0.010 |
Age in 1991 yrs | 40.7±12.0 | 41.4±11.3 | 0.005 |
Being a smoker in 1991 % | 37.6 | 29.1 | <0.001 |
Being a never-smoker in 1991 % | 39.7 | 48.2 | <0.001 |
Being a smoker in 2002 % | NA | 21.8 | |
Being a never-smoker in 2002 % | NA | 46.9 | |
Pack-yrs in smokers 1991 | 17.7 (7.3–31.7) | 18.4 (8.0–31.8) | 0.470 |
Pack-yrs in smokers 2002 | NA | 21.6 (8.6–35.9) | |
High educational level in 1991 % | 15.8 | 17.3 | 0.058 |
FVC in 1991 L | 4.4±1.0 | 4.5±1.0 | <0.001 |
Change in FVC up to 2002 L | −0.3±0.4 | ||
FEV1 in 1991 L | 3.5±0.9 | 3.6±0.8 | 0.004 |
Change in FEV1 up to 2002 L | −0.4±0.3 | ||
FEV1/FVC ratio >0.7 in 1991 % | 86.9 | 89.8 | <0.001 |
FEF25–75% in 1991 L·s−1 | 3.4±1.3 | 3.4±1.2 | 0.952 |
Change in FEF25–75% up to 2002 L·s−1 | −0.8±0.7 | ||
Change in PM10 exposure during follow-up μg·m−3 | NA | −5.3 (−7.3– −4.2) |
Data are presented as mean±sd or median (interquartile range), unless stated otherwise. #: 4,685 subjects (sample size may decrease to 4,517 due to missing values); ¶: 4,365 subjects; +: included versus not included, significant p-values are presented in bold. FVC: forced vital capacity; FEV1: forced expiratory volume in 1 s; FEF25–75%: forced expiratory flow at 25–75% of FVC; PM10: particulate matter with a 50% cut-off aerodynamic diameter of 10 μm.