Never-smokers | Smokers without COPD | COPD I–II | COPD III–IV | p-value# | |
Subjects | 10 | 22 | 28 | 14 | |
Sex ratio male/female | 3/7 | 17/5 | 27/1 | 6/8 | p<0.001 |
Age yrs | 56.3±11.2 | 59.9±10.6 | 63.3±9.0 | 58.8±5.4 | p = 0.17 (ns) |
Smoking history pack-yrs | 0 | 33.0±26.2 | 45.9±22.4 | 30.7±16.0 | p<0.001 |
Smoking status current/ex-smoker | NA | 12/10 | 19/9 | 3/11 | p = 0.02 |
FEV1 % pred | 100.6±12.1 | 103.2±17.8 | 80.9±11.0 | 29.9±10.4 | p<0.001 |
FEV1/FVC % | 77.3±7.3 | 77.8±5.2 | 60.1±6.0 | 40.4±11.6 | p<0.001 |
LABA yes/no | 0/10 | 0/22 | 2/26 | 12/2 | p<0.001 |
Inhaled corticosteroids yes/no | 0/10 | 0/22 | 0/28 | 12/2 | p<0.001 |
Inhaled corticosteroid dose μg BDP per 24 h | 0 | 0 | 0 | 1353.9±659.1 | p<0.001 |
Systemic corticosteroids yes/no | 0/10 | 0/22 | 0/28 | 9/5 | p<0.001 |
Systemic corticosteroid dose mg prednisolone per 24 h | 0 | 0 | 0 | 4.6±4.1 | p<0.001 |
Data are expressed as mean±sd or n, unless otherwise stated. COPD: chronic obstructive pulmonary disease; FEV1: forced expiratory volume in 1 s; % pred: % predicted; FVC: forced vital capacity; LABA: long-acting β2-agonist; BDP: beclomethasone diproprionate; NA: not available; ns: nonsignificant. #: indicates p-value generated by Kruskal–Wallis test for continuous variables and Fisher exact test for categorical variables.