Characteristics of the 109 study patients with COPD measured at recruitment and of the 32 who recorded FEV1
| Median | Interquartile range | Median | Interquartile range | |
|---|---|---|---|---|
| FEV1=forced expiratory volume in 1 second; FVC=forced vital capacity; PEF=peak expiratory flow; Pao2; Paco2=arterial oxygen and carbon dioxide tensions. | ||||
| (n=109) | (n=32) | |||
| Age (years) | 68.1 | 62.5–73.8 | 66.8 | 60.7–73.7 |
| FEV1 (l) | 1.00 | 0.74–1.3 | 1.00 | 0.77–1.48 |
| FEV1 (% predicted) | 38.2 | 27.0–50.0 | 36.0 | 24.7–50.2 |
| FEV1 (% reversibility) | 5.2 | 0–12.8 | 6.9 | 0–14.1 |
| FVC (l) | 2.51 | 1.86–2.94 | 2.60 | 2.00–2.90 |
| FEV1/FVC (%) | 42.3 | 33.1–53.3 | 45.1 | 32.3–53.5 |
| PEF (l/min) | 200 | 150–264 | 245 | 180–300 |
| Pao2 (kPa) | 9.00 | 8.27–9.51 | 9.05 | 8.31–9.92 |
| Paco2 (kPa) | 5.77 | 5.40–6.36 | 5.85 | 5.49–6.46 |
| Smoking (years) | 40 | 30–50 | 40 | 30–46 |
| % of 109 | % of 32 | |||
| Sex (male) | 74.3 | 90.6 | ||
| Chronic dyspnoea | 45.0 | 50.0 | ||
| Chronic wheeze | 33.0 | 37.5 | ||
| Chronic cough | 49.5 | 43.8 | ||
| Chronic sputum production | 56.0 | 43.8 | ||
| Smoking at recruitment | 30.8 | 31.2 | ||
| Taking inhaled steroids | 91.7 | 87.5 | ||