Table 1 Baseline characteristics of the subgroups under and above 60 years stratified according to GOLD groups

GOLD (mMRC)

GOLD A

GOLD B

GOLD C

GOLD D

Total

p

GOLD A

GOLD B

GOLD C

GOLD D

Total

p

n = 1969

p

n = 207

n = 91

n = 86

n = 128

n = 512

n = 582

n = 389

n = 180

n = 306

n = 1457

Gender (m/f)

123/84

46/45

48/38

68/60

285/227

0.478

375/207

257/132

118/62

181/125

931/526

0.254

1216/753

0.205

Age (y)

53.7 ± 4.7

54.0 ± 4.4

53.1 ± 5.1

54.8 ± 3.7

53.9 ± 4.5

0.049

68.7 ± 5.6

69.2 ± 5.9

68.4 ± 5.4

68.3 ± 5.4

68.7 ± 5.6

0.192

64.9 ± 8.4

< 0.001

BMI (kg/m²)

26.3 ± 4.9

28.3 ± 6.5

26.0 ± 4.7

26.6 ± 6.4

26.7 ± 5.6

0.022

26.3 ± 4.5

27.4 ± 5.3

25.9 ± 4.3

27.1 ± 5.8

26.7 ± 5.0

< 0.001

26.7 ± 5.2

< 0.001

Pack years

38.9 ± 26.8

47.3 ± 33.0

41.9 ± 28.3

45.3 ± 36.3

42.5 ± 30.9

0.124

51.2 ± 36.7

54.4 ± 37.7

47.1 ± 35.5

52.3 ± 39.4

51.8 ± 37.4

0.203

49.3 ± 36.0

0.027

DemTect Score

15.6 ± 3.0

16.1 ± 3.1

16.2 ± 2.8

15.6 ± 3.2

15.8 ± 3.0

0.314

16.5 ± 2.7

16.3 ± 2.8

15.9 ± 2.9

16.1 ± 3.0

16.3 ± 2.8

0.039

16.2 ± 2.9

0.169

FEV₁% predicted

59.2 ± 17.0

44.1 ± 15.4

51.8 ± 17.6

41.1 ± 16.4

50.7 ± 18.3

< 0.001

62.2 ± 18.1

49.6 ± 16.5

55.4 ± 16.0

44.3 ± 14.8

54.3 ± 18.2

< 0.001

53.4 ± 18.3

< 0.001

FVC % predicted

84.8 ± 17.6

71.2 ± 16.1

80.7 ± 15.9

67.2 ± 18.3

77.3 ± 18.8

< 0.001

86.5 ± 18.1

75.9 ± 17.1

82.8 ± 16.5

69.6 ± 17.6

79.7 ± 18.8

< 0.001

79.1 ± 18.8

< 0.001

CaO₂ ml/100 ml

19.2 ± 1.6

18.9 ± 1.6

19.1 ± 1.5

18.7 ± 1.7

19.0 ± 1.6

0.026

18.9 ± 1.7

18.5 ± 1.8

18.4 ± 1.6

18.1 ± 1.8

18.6 ± 1.8

< 0.001

18.7 ± 1.7

< 0.001

SGRQ sum score

31.7 ± 16.0

52.7 ± 15.4

38.4 ± 15.5

61.1 ± 13.4

43.9 ± 19.6

< 0.001

29.1 ± 14.9

51.1 ± 15.5

38.9 ± 16.9

59.2 ± 15.5

42.5 ± 19.8

< 0.001

42.9 ± 19.7

< 0.001

PHQ-9 sum score

5.7 ± 4.2

9.0 ± 5.4

7.3 ± 4.2

10.1 ± 5.0

7.7 ± 5.0

< 0.001

4.1 ± 3.4

6.6 ± 4.5

5.3 ± 3.9

8.0 ± 5.1

5.7 ± 4.5

< 0.001

6.2 ± 4.7

< 0.001

6-MWD (m)

488 ± 85.4

404.6 ± 83.6

466.4 ± 98.8

385.7 ± 98.8

444.1 ± 101.1

< 0.001

460.9 ± 79.1

372.1 ± 97.8

447.6 ± 91.5

339.4 ± 106.2

410.1 ± 105.3

< 0.001

418.9 ± 105.2

< 0.001

CRP (Median/ Interquartile range)

0.31/0.46

0.40/0.73

0.46/0.42

0.50/0.68

0.41/0.43

0.006

0.36/0.42

0.50/ 0.59

0.50/0.47

0.50/0.59

0.45/0.50

0.003

0.43/0.49

< 0.001

Diagnosis of cognitive impairment (%)

8 (3.9)

9 (9.9)

4 (4.7)

9 (7.0)

30 (5.9)

0.194

26 (4.5)

21 (5.4)

5 (2.8)

22 (7.2)

74 (5.1)

0.149

1865/104

0.063