Table 1.
Characteristics of study participants
| Healthy never-smokers | Healthy smokers | COPD | |
|---|---|---|---|
| Number of subjects | 10 | 20 | 40 |
| Sex (male/female) | 6/4 | 11/9 | 22/18 |
| Age (years) | 57.53±2.12 | 57.85±2.00 | 67.40±1.12a,b |
| Time since diagnosis (years) | N/A | N/A | 7.05±1.00 |
| Smoking exposure (pack-years) | N/A | 32.14±2.96 | 41.99±2.78b |
| Smoking status (current smokers/ex-smokers) |
0/0 | 20/0 | 17/23 |
| FEV1 (% predicted) | 109.4±2.77 | 96.88±6.26 | 61.98±2.76a,b |
| FEV1/FVC% | 80.39±1.34 | 74.39±1.18 | 52.49±1.57a,b |
| BMI (kg/m2) | 28.42±1.04 | 27.72±0.68 | 28.39±1.05 |
| 6MWT (m) | N/A | N/A | 388.6±11.08 |
| CAT (score) | N/A | N/A | 15.8±1.18 |
| mMRC (median, min–max) | N/A | N/A | 1 (0–3) |
| BODE index (median, min–max) | N/A | N/A | 1 (0–6) |
| Sputum macrophages (%) | 65.69±3.76 | 56.85±1.99 | 44.70±41a,b |
| Sputum neutrophils (%) | 18.89±3.77 | 23.28±2.23 | 37.40±4.93a |
| Sputum lymphocytes (%) | 6.43±0.84 | 4.26±0.72 | 6.60±1.99 |
| Sputum eosinophils (%) | 0.89±0.28 | 1.43±0.28 | 2.93±0.95 |
Notes: aCOPD vs Healthy never-smokers, P<0.05; bCOPD vs Healthy smokers, P<0.05. BODE index, BMI, airway obstruction, dyspnea, exercise capacity.
Abbreviations: BMI, body mass index; 6MWT, six-minute walk test; CAT, COPD Assessment Test; mMRC, modified Medical Research Council dyspnea scale.