Asthmatic | Healthy controls | |||||
Smokers | Never-smokers | p-value | Smokers | Never-smokers | p-value | |
Subjects n | 39 | 36 | 30 | 48 | ||
Age yrs | 47.4±7.4 | 45.1±10.9 | 0.42 | 39.9±8.6 | 35.2±8.0 | 0.029 |
Male n | 20 | 29 | 0.008 | 10 | 17 | 0.85 |
Asthma duration yrs | 21.7±15.7 | 28.9±17.2 | 0.07 | |||
Smoking history pack-yrs | 37.7±17.2*** | 22.8±14.9 | ||||
Cigarettes·day-1 | 22.6±7.5* | 19.3±7.1 | ||||
Smoking history yrs | 30.6±7.2*** | 23.3±8.6 | ||||
Equivalent dose of inhaled beclometasone μg | 997±905 | 631±646 | 0.11 | |||
FEV1 L | 1.95±0.70 | 2.26±0.77 | 0.045 | 2.84±0.81 | 3.35±0.93 | 0.014 |
FEV1 % pred | 63.3±13.9 | 63.6±17.5 | 0.70 | 93.4±12.5 | 99.7±13.9 | 0.039 |
FEV1 post-salbutamol % pred | 77.5±5.5 | 82.6±6.4 | 0.44 | |||
FEV1/FVC pre-salbutamol | 61.7±11.4 | 60.9±14.1 | 0.98 | 77.5±5.5 | 82.6±6.4 | <0.001 |
FEV1/FVC post-salbutamol | 65.0±12.1 | 64.8±15.2 | 0.77 | |||
Reversibility to salbutamol % | 22.7±11.4 | 25.6±11.9 | 0.23 | |||
Reversibility to salbutamol mL | 426±236 | 549±269 | 0.014 | |||
ATS impairment score | 5.1±1.9 | 5.2±1.9 | 0.829 | |||
Asthma control score | 2.66±1.08 | 1.67±0.83 | <0.001 |
Data are presented as mean±sd, unless otherwise stated. FEV1: forced expiratory volume in one second; % pred: % predicted; FVC: forced vital capacity; ATS: American Thoracic Society. *: p<0.05, smokers with asthma versus healthy smokers; ***: p<0.001, smokers with asthma versus healthy smokers.