Non-smokers without emphysema (NE-NS)(n-11) | Smokers without emphysema (NE-S)(n = 9) | Patients with severe emphysema (SE)(n = 10) | Between group differences (p value) | |
Median (range) age (years) | 58 (32–72) | 58.5 (30–68) | 57.5 (49–65) | 0.99 |
Sex ratio (F/M) | 2/9 | 0/9 | 1/9 | 0.28 |
Median (range) no of packs smoked | 0 | 37.5 (10–50)‡ | 52 (20–100)†‡ | 10−4 |
Time since smoking cessation (years) | NA | 0 (0–20) | 1 (0–8) | 0.88 |
Current smokers/ex-smokers | NA | 7/2 | 2/8 | 10−4 |
†p = 10−3 vs NE-S; ‡p = 10−4 vs NE-NS as assessed by the Mann-Whitney U-test. NA, not applicable.