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) | |
FEV1 % predicted (% pred) | 79 (68–101) | 78 (60–110) | 22 (13–47)†‡ | 10−4 |
FEV1/FVC | 90 (71–105) | 68 (64–85)‡ | 43.5 (35–50) †‡ | 10−4 |
RV (% pred) | 95 (55–117) | 117 (96–132) | 241 (207–349)†‡ | 10−4 |
TLC (% pred) | 82.5 (76–99) | 100 (84–116)‡ | 130 (110–153)†‡ | 10−4 |
Pao2 (kPa) | 11.4 (10.1–12.4) | 11.3 (10.1–13.3) | 9 (7.3–10.9)†‡ | 8.10−4 |
Paco2 (kPa) | 5.5 (5.1–6) | 5.3 (4.8–6.1) | 5.7 (4.5–6.7) | 0.36 |
Tlco (% pred) | Not done | Not done | 43.5 (15–67) | Non-relevant |
6 min walk test (m) | Not done | Not done | 350 (70–540) | Non-relevant |
†p = 10−4 vs NE-S; ‡p = 10−4 vs NE-NS as assessed by the Mann-Whitney U-test.
FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; Pao2, arterial oxygen tension; Paco2, arterial carbon dioxide tension; RV, residual volume; TLC, total lung capacity; Tlco, carbon monoxide lung transfer factor.