Table 1 Baseline characteristics, results of the pulmonary function test and the oscillometry

Age

69 (64 – 75)

68 (65 – 74)

69 (63 – 75)

0.958

Sex Men / Women

140 / 38

92 / 27

34 / 8

0.623

Outcome

 Survival / Death / Unknown

73 / 81 / 24

GAP stage I / II / III

93 / 64 / 21

72 / 41 / 6

15 / 14 / 13

 < 0.001*

BMI

23.5 (21.5 – 25.9)

23.5 (22.2 – 25.9)

22.7 (20.2 – 25.7)

0.102

Smoking

 Current or former / Never

146 / 32

98 / 21

34 / 8

0.839

 Pack-years

35 (10 – 50)

35 (10 – 50)

35 (7 – 49)

0.692

Comorbidities

 Acute exacerbation of ILD^a

4 (2.3)

1 (1.1)

3 (7.3)

0.024*

 Cancer other than lung cancer

17 (10.6)

12 (12.8)

1 (2.4)

0.115

 Hypertension

63 (54.8)

42 (44.7)

14 (34.1)

0.819

 Hyperlipidemia

40 (29.0)

18 (19.1)

13 (31.7)

0.025*

 Diabetes

40 (29.0)

29 (30.9)

7 (17.1)

0.303

 Heart diseases

27 (17.9)

12 (12.8)

8 (19.5)

0.130

 Arrhythmia

7 (4.1)

3 (3.2)

4 (9.8)

0.056

 Pulmonary hypertension

7 (4.1)

5 (5.3)

1 (2.4)

0.592

 Cerebrovascular diseases

14 (8.5)

8 (8.5)

5 (12.2)

0.289

 Gastroesophageal reflux

14 (8.5)

11 (11.7)

3 (7.3)

0.678

 Chronic renal diseases

17 (10.6)

10 (10.6)

7 (17.1)

0.090

 Bronchial asthma

10 (6.0)

8 (8.5)

2 (4.9)

0.651

Indices of the PFT

 VC (L)

2.63 (2.18 – 3.39)

2.95 (2.39 – 3.56)

2.23 (1.76 – 2.59)

 < 0.001^*

 %VC

87.8 (71.0 – 102.0)

96.5 (77.4 – 109.0)

70.3 (59.3 – 80.2)

 < 0.001^*

 FVC (L)

2.60 (2.12 – 3.35)

2.89 (2.29 – 3.49)

2.12 (1.77 – 2.60)

 < 0.001^*

 %FVC

86.1 (69.7 – 101.7)

95.7 (78.1 – 107.1)

68.4 (59.7 – 80.6)

 < 0.001^*

 FEV1 (L)

2.15 (1.82 – 2.61)

2.27 (1.91 – 2.73)

1.91 (1.63 – 2.26)

 < 0.001^*

 FEV1/FVC (%)

82.6 (77.4 – 87.6)

81.2 (76.7 – 84.6)

88.8 (83.5 – 93.4)

 < 0.001^*

 DLCO (ml/min/mmHg)^b

11.37 (9.36 – 14.91)

12.27 (10.01 – 15.61)

9.94 (8.54 – 11.99)

 < 0.001^*

 %DLCO^b

55.2 (44.5 – 66.3)

58.6 (48.5 – 71.8)

45.8 (35.9 – 57.0)

 < 0.001^*

Indices of the oscillometry

R5 (cmH2O/L/s)

 Whole breath

2.70 (2.28 – 3.24)

2.73 (2.30 – 3.31)

2.78 (2.28 – 3.24)

0.817

 Ex

2.84 (2.39 – 3.70)

2.86 (2.44 – 3.69)

2.83 (2.39 – 3.73)

0.703

 In

2.46 (1.99 – 3.01)

2.47 (1.95 – 3.02)

2.42 (2.11 – 2.98)

0.774

 ΔR5

0.37 (0.15 – 0.75)

0.38 (0.17 – 0.88)

0.39 (0.04 – 0.74)

0.872

R20 (cmH2O/L/s)

 Whole breath

2.07 (1.76 – 2.48)

2.15 (1.79 – 2.51)

1.94 (1.75 – 2.63)

0.424

 Ex

2.13 (1.80 – 2.67)

2.22 (1.81 – 2.70)

2.04 (1.78 – 2.80)

0.330

 In

1.99 (1.68 – 2.42)

1.99 (1.70 – 2.44)

1.88 (1.66 – 2.42)

0.494

 ΔR20

0.12 (–0.05 – 0.40)

0.10 (–0.04 – 0.48)

0.16 (–0.11 – 0.39)

0.526

R5–R20 (cmH2O/L/s)

 Whole breath

0.62 (0.43 – 0.83)

0.60 (0.39 – 0.82)

0.62 (0.46 – 0.84)

0.474

 Ex

0.76 (0.48 – 1.00)

0.75 (0.47 – 0.99)

0.81 (0.60 – 1.00)

0.586

 In

0.47 (0.32 – 0.69)

0.47 (0.30 – 0.68)

0.49 (0.38 – 0.70)

0.376

 ΔR5–R20

0.25 (0.08 – 0.43)

0.25 (0.10 – 0.45)

0.28 (0.11 – 0.42)

0.817

X5 (cmH2O/L/s)

 Whole breath

–0.87 (–1.16 to –0.48)

–0.75 (–1.04 to –0.40)

–1.14 (–1.66 to –0.97)

 < 0.001^*

 Ex

–0.90 (–1.24 to –0.44)

–0.78 (–1.14 to –0.33)

–1.15 (–1.47 to –0.84)

 < 0.001^*

 In

–0.82 (–1.17 to –0.50)

–0.73 (–0.98 to –0.37)

–1.18 (–1.87 to –0.83)

 < 0.001^*

 ΔX5

0.04 (–0.12 – 0.20)

0.03 (–0.14 – 0.19)

0.07 (–0.05 – 0.25)

0.121

Fres (Hz)

 Whole breath

10.38 (7.88 – 12.34)

9.63 (7.46 – 11.17)

11.87 (10.38 – 14.30)

 < 0.001^*

 Ex

10.16 (7.80 – 12.48)

9.61 (7.16 – 11.72)

11.82 (10.08 – 13.80)

 < 0.001^*

 In

10.22 (8.20 – 12.09)

9.50 (7.57 – 11.32)

11.80 (10.22 – 14.83)

 < 0.001^*

 ΔFres

–0.14 (–1.11 – 0.76)

–0.18 (–1.04 – 0.94)

–0.22 (–1.22 – 0.22)

0.281

ALX (cmH2O/L/s)

 Whole breath

3.71 (1.74 – 5.85)

3.06 (1.34 – 4.80)

5.62 (4.13 – 9.30)

 < 0.001^*

 Ex

3.72 (1.57 – 6.01)

2.86 (1.07 – 5.37)

5.66 (3.50 – 8.42)

 < 0.001^*

 In

3.43 (1.83 – 5.68)

2.95 (1.28 – 4.55)

5.84 (3.44 – 11.17)

 < 0.001^*

 ΔALX

–0.24 (–0.97 – 0.62)

–0.13 (–0.72 – 0.67)

–0.62 (–1.53 – 0.38)

0.013^*