Table 1 Characteristics of subjects

Gender^a

 Male

103 (74.1)

50 (90.9)

36 (90.0)

24 (72.7)

 Female

36 (25.9)

5 (9.1)

4 (10.0)

9 (27.3)

Age, mean ± SEM, years

63.1 ± 0.9

64.5 ± 1.2

65.4 ± 1.2

62.6 ± 0.9

BMI, mean ± SEM, kg/m²

27.3 ± 0.4

26.9 ± 0.5

28.4 ± 0.6

26.7 ± 0.6

Smoking history^aa

 Never smoker

30 (21.6)

0

0

11 (33.3)

 Former smoker

27 (19.4)

7 (12.7)

19 (47.5)

10 (30.3)

 Current smoker

82 (59.0)

48 (87.3)

21 (52.5)

12 (36.4)

Smoking pack-years, median (range):

 Former smoker

28.0 (10–54)

30.0 (15–40)

33.0 (13–57)

22.0 (11–44)

 Current smoker

38.0 (10–60)

40.0 (12–60)

39.5 (10–94)

32.0 (20–56)

FEV_1, mean ± SEM, % pred

91.2 ± 1.7*

56.7 ± 1.6^§

55.7 ± 2.3^§

106.6 ± 3.0

FEV₁/FVC ratio, mean ± SEM, % pred

96.6 ± 0.7*

70.6 ± 1.1^§

74.0 ± 1.8^§

104.8 ± 0.4