Table 2 Baseline characteristic of patients stratified by quartiles of CT emphysema severity

Subjects (n)

9

11

13

10

Demographics

Age years

64 ± 9

65 ± 8

67 ± 7

66 ± 8

NS

Male sex %

68

70

78

76

 < 0.001

BMI (kg m⁻²)

26 ± 7

27 ± 5

25 ± 6

23 ± 6

 < 0.001

BMI < 21 kg m⁻²%

14

12

19

30

 < 0.001

Smoking status

Pack-years

41 ± 19

40 ± 21

43 ± 22

45 ± 19

 < 0.01

Current smoker %

33

30

15

14

 < 0.001

Medications %

Inhaled steroids

15

25

56

52

 < 0.001

Oral corticosteroids

0

0

0

0

NS

Physiology

FEV₁% pred

59 ± 13

52 ± 14

46 ± 14

44 ± 16

 < 0.01

FEV₁/FVC %

55 ± 9

51 ± 10

41 ± 9

43 ± 6

 < 0.01

Oxygen saturation %

95.8 ± 2.9

96.2 ± 3.9

92.8 ± 3.4

91.4 ± 2.3

 < 0.001

Comorbidities (%)

Cardiovascular diseases

15

20

17

13

 < 0.01

Osteoporosis

18

20

35

42

 < 0.01

Diabetes

9

10

5

6

 < 0.01

Longitudinal outcomes

COPD hospitalizations PPPY*

0.4

0.8

1.6

3.4

 < 0.001

COPD exacerbations PPPY*

1.2

2.6

3.4

3.8

 < 0.001

FEV₁ decline mL·year⁻¹

28 ± 26

32 ± 30

35 ± 33

36 ± 32

 < 0.01