Table 1—

Patient characteristics

COPDControls
Subjects n11428
Male/female n99/1511/17
Age yrs62±851±4
Current/ex-smokers n72/4227/1
Smoking history pack-yrs#42 (31–55)31 (25–37)
Postbronchodilator FEV1 % pred63±9108±12
Postbronchodilator FEV1/IVC %48±978±4
PC20 methacholine mg·mL−1¶0.6±2.826.7±1.7
  • Data are presented as mean±sd, unless stated otherwise. #: median (25th–75th percentile); : geometric mean±doubling dose. COPD: chronic obstructive pulmonary disease; FEV1 = forced expiratory volume in one second; % pred = percentage of predicted value; IVC = inspiratory vital capacity; PC20 methacholine = the provocative concentration of methacholine causing a 20% fall in FEV1.