Table 1—

Characteristics of the sample of the Vlagtwedde–Vlaardingen cohort investigated at the last survey

Total populationEver-smokers#
Subjects n1390945
Males714 (51.4)610 (64.6)
Age yrs52 (35–79)50 (35–79)
Pack-yrs of smoking8.0 (0–262.2)18.8 (0–262.2)
FEV1 % pred92.6±15.390.6±15.5
VC % pred101.8±14.5100.2±14.0
FEV1/VC %73.9±8.772.4±9.2
COPD GOLD stage II or over167 (12.4)140 (15.3)
BHR PC10 ≤8 mg·mL−1 histamine190 (46.5)141 (50.4)
Genotype frequency % heterozygotes/ % homozygotes mutant
SOD2 Ala16Val49.6/23.849.8/23.6
SOD2 C5774T29.3/4.528.8/5.2
SOD3 Ala40Thr43.5/11.942.0/12.1
SOD3 Arg213Gly3.8/0.04.1/0.0
SOD3 G(-4466)T8.6/0.28.9/0.3
  • Data are presented as n (%), median (range) or mean±sd, unless otherwise indicated. FEV1: forced expiratory volume in one second; % pred: % predicted; VC: vital capacity; COPD: chronic obstructive pulmonary disease; GOLD: Global Initiative for Chronic Obstructive Lung Disease; BHR: bronchial hyperresponsiveness; PC10: the histamine concentration causing an FEV1 decrease of ≥10% from baseline. #: subpopulation of the total population. : BHR test performed on a random subgroup (n = 409) of the total population (n = 1,390).