Table 1

 Characteristics of participants included in the analysis

All(n = 5158)Men(n = 2628)Women(n = 2530)p Value‡
BMI, body mass index; SOB, shortness of breath; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; BHR, bronchial hyperresponsiveness.
*Mean (SD).
†FEV1  =  residual FEV1 + FEV1 mean.
‡For difference between sex groups using t test for continuous variables and χ2 test for categorical variables.
Age (%)
    <40 years38.239.137.20.38
    40–50 years42.241.642.8
    >50 years19.619.320.0
Age when finished education (%)
    ⩽16 years17.016.018.10.11
    17–21 years36.137.035.2
    >21 years46.947.046.7
BMI (%)
    <25 kg/m252.143.461.2<0.001
    25–30 kg/m235.844.826.5
    >30 kg/m212.111.812.3
Smoking (%)
    Never smokers43.639.647.7<0.001
    Past smokers24.826.722.8
    Moderate smokers20.319.521.2
    Heavy smokers11.314.28.3
Atopy (%)28.532.624.2<0.001
Asthma-like symptoms (%)24.125.223.00.07
    Wheeze20.522.218.80.003
    SOB at rest5.24.06.3<0.001
    Woken by SOB5.24.95.60.31
Current asthma (%)4.94.45.40.11
Family history of asthma (%)11.09.712.40.002
FEV1 (l)*†3.60 (0.65)4.14 (0.40)3.03 (0.30)<0.001
FEV1 (% pred)*107 (14)106 (13)108 (14)<0.001
FVC (% pred)*111 (14)108 (13)115 (14)<0.001
BHR (%)13.09.416.6<0.001
Usual frequency of exercise (%)
    ⩽1 time/week60.058.961.00.15
    2–3 times/week26.527.725.3
    ⩾4 times/week13.513.413.7
Usual duration of exercise (%)
    <1 h/week41.538.244.9<0.001
    1–3 h/week42.442.842.0
    ⩾4 h/week16.119.013.1