Mean (range) characteristics of study subjects
| Asymptomatic smokers (n=6) | Fluticasone propionate (n=10) | Placebo (n=13) | |
|---|---|---|---|
| FEV1=forced expiratory volume in 1 second; FVC=forced vital capacity; PC20=concentration provoking a fall in FEV1 of 20% or more; ND = not done. | |||
| *p=0.02, †p=0.01 asymptomatic smokers v COPD patients. | |||
| ‡One patient with FEV1 of 93% predicted could be included because his FEV1/FVC was 0.49. | |||
| M/F | 3/3 | 8/2 | 11/2 |
| Age (years) | 44 (32–56) | 54 (42–65) | 56 (42–67) |
| No cigarettes/day | 21 (13–40) | 15 (6–30) | 16 (6–30) |
| Pack years | 23 (6–82) | 25 (5–50) | 26 11–50) |
| Serum IgE (U/l) | ND | 72 (12–172) | 81 (7–405) |
| Blood eosinophils (×103/l) | ND | 163 (20–440) | 195 (24–360) |
| FEV1 (l) | 2.8 (2.1–3.5)* | 2.1 (1.5–3.1) | 2.0 (1.3–2.9) |
| FEV1 (% predicted) | 93 (79–101)† | 66 (55–93)‡ | 61 (34–72) |
| Reversibility (% predicted) | 4.0 (0–8) | 5.3 (0–9.8) | 5.6 (0–9.9) |
| FEV1/FVC | 0.79 (0.76–0.84) | 0.56 (0.48–0.60) | 0.56 (0.46–0.61) |
| PC20 histamine (mg/ml) | >8 | 2.6 (0.1–8.0) | 0.8 (0.1–2.3) |
| PC20 methacholine (mg/ml) | ND | 6.3 (0.7–17.4) | 2.6 (0.4–16.5) |