Table 3—

Patient demographics

BTS groupSputum group
Subjects n4042
Age yrs70 (49–80)68 (45–82)
Smoking n
 Current smoker812
Smoking pack-yrs47.5±27.850.6±30.0
FEV1 L1.07±0.440.96±0.47
FVC L2.28±0.842.11±0.67
Post-bronchodilator FEV1 L1.14±0.481.04±0.50
FEV1 % pred38.4±15.538.1±15.4
TLC % pred98.6±15.399.7±15.4
RV % pred123.6±38.1133.1±47.1
KCO % pred75.0±17.965.5±22.9
Baseline sputum eosinophil %#1.5±0.61.7±0.6
Blood eosinophils ×109·L−10.24±0.240.20±0.15
Exhaled nitric oxide ppb5.3±6.57.6±8.9
Serum IgE#61.6±0.736.3±0.7
Baseline inhaled steroid dose1200±1007.61024±902.2
Patients admitted in previous year n1212
Rate of admission in previous year0.55±0.70.43±0.6
Attended pulmonary rehab within 1-yr prior to study n109
  • Data are presented as mean (range) or mean±sd, unless otherwise stated. BTS: British Thoracic Society; FEV1: forced expiratory volume in one second; FVC: forced vital capacity; % pred: % predicted; TLC: total lung capacity; RV: residual volume; KCO: corrected gas transfer; BMI: body mass index; Ig: immunoglobulin. #: Geometric mean; : beclomethasone diproprionate equivalent μg·day−1.