Table 1—

Demographic and clinical characteristics of participating chronic obstructive pulmonary disease(COPD) patients

Subjects n827
Sociodemographic characteristics
 Age yrs69±10
 BMI kg·m−227.7±4.2
 Male sex %86.5
 Cigarette smoking
  Current %21.6
  Former %75.1
  History pack-yrs47.0±28.0
 Education %
  Less than primary school42.3
  Finished primary school37.1
  Finished secondary school12.2
  University and/or college7.1
COPD clinical characteristics
 Time since COPD diagnosis yrs10.3±7.7
 COPD exacerbations in last year2.2±1.9
 Hospitalisations due to COPD in last year0.5±0.99
 FVC mL2749±851
  % pred68±20
 FEV1 mL1521±555
  % pred54.6±17.7
 FEV1/FVC %56.9±10.1
 MRC dyspnoea grade %
  08.3
  146.7
  224.9
  315.6
  43.9
 GOLD COPD severity classification %
  I: mild (FEV1≥80%)4.1
  II: moderate (50%≤FEV1<80%)53.8
  III: severe (30%≤FEV1<50%)31.9
  IV: very severe (FEV1<30%)8.0
  • Data are presented as mean±sd unless otherwise indicated. Percentages may not add up to 100 due to missing data (one patient with no specified sex, 37 with no specified smoking habits, 12 with no specified educational level and five with no specified UK Medical Research Council (MRC) dyspnoea grade). BMI: body mass index; FEV1: forced expiratory volume in one second; FVC: forced vital capacity; GOLD: Global Initiative for Chronic Obstructive Lung Disease; % pred: percentage of the predicted value.