Table 2 Pulmonary function tests
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/FVC90 (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 doneNot done43.5 (15–67)Non-relevant
6 min walk test (m)Not doneNot done350 (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.