Table 2 Pulmonary function and peak responses to cardiopulmonary exercise tests at baseline and 4.5 years apart

Sex, male/female (n)

35/28

Weight (kg)

76.4 ± 17.5

76.0 ± 17.4

−0.4 ± 5.2

0.599

FEV₁(L)

1.60 ± 0.53

1.46 ± 0.57

−0.15 ± 0.28

<0.001

FEV₁ (% pred)

51.4 ± 13.5

48.0 ± 14.8

−3.4 ± 9.5

0.006

FVC (L)

3.47 ± 0.89

3.14 ± 0.86

−0.34 ± 0.50

<0.001

FVC (% pred)

90.1 ± 17.2

82.8 ± 15.3

−7.4 ± 14.7

<0.001

FEV₁/FVC (%)

46.4 ± 10.8

46.0 ± 11.2

−0.4 ± 0.05

0.549

Exercise time (min)

6.44 ± 1.88

6.44 ± 2.18

−0.01 ± 1.61

0.980

V̇O_2peak (L ∙ min⁻¹)

1.57 ± 0.57

1.36 ± 0.54

−0.22 ± 0.29

<0.001

V̇CO_2peak (L ∙ min⁻¹)

1.65 ± 0.69

1.34 ± 0.67

−0.31 ± 0.37

<0.001

V̇_Epeak/MVV

0.98 ± 0.22

0.94 ± 0.19

−0.03 ± 0.20

0.196

V̇_Epeak (L ∙ min⁻¹)

53.8 ± 19.2

47.3 ± 19.6

−6.5 ± 11.6

<0.001

V_Tmax (L)²

1.71 ± 0.51

1.48 ± 0.43

−0.23 ± 0.41

<0.001

HR_peak (bpm)

138 ± 20

133 ± 19

−5 ± 14

0.004

RER

1.03 ± 0.12

0.96 ± 0.14

−0.08 ± 0.11

<0.001

Dyspnea (Borg Scale)

9.0 ± 1.6

8.7 ± 1.6

−0.3 ± 1.8

0.327

Leg discomfort (Borg Scale)

5.6 ± 2.8

5.9 ± 3.0

0.3 ± 2.8

0.651

IC_rest

2.36 ± 0.75

2.21 ± 0.78

−0.13 ± 0.48

0.039

ΔIC(L)

0.41 ± 0.40

0.46 ± 0.33

0.05 ± 0.38

0.208

IRV (L)

0.44 ± 0.37

0.38 ± 0.26

−0.05 ± 0.34

0.233

MVV (L ∙ min⁻¹)

56.0 ± 18.6

51.0 ± 20.1

−5.1 ± 9.8

<0.001

SpO₂ start (%)

97.1 ± 2.2

95.9 ± 2.5

−1.2 ± 3.2

0.004

SpO₂ end (%)

92.8 ± 5.1

89.6 ± 5.1

−3.2 ± 4.4

<0.001

  Intercept (a)¹

-0.05 (0.47)

−0.18 (0.44)

-0.13 (0.46)

0.032

  Slope (b)¹

0.063 (0.032)

0.076 (0.035)

0.014 (0.037)

0.007

  Curvature (c)¹

−0.00071 (0.00059)

−0.00105 (0.00079)

−0.00036 (0.00077)

0.002