Table 1 Comparison of the baseline characteristics in patients with IPF according to the HRCT patterns

No. of patients

163

110

33

31

Age, years

61.9 ± 7.6

62.9 ± 7.3

63.0 ± 7.7

63.5 ± 7.8

Male

133 (81.6)

71 (64.5)^†

29 (87.9)

17 (54.8)^†

Ever-smokers

126 (77.3)

66 (60.0) ^†

28 (84.8)

12 (38.7) ^†

PFT, % predicted (n = 336)

n = 163

n = 110

n = 33

n = 30

 FVC

69.9 ± 18.5^†

73.7 ± 14.9^†

84.6 ± 13.6

66.7 ± 18.5^†

 DL_CO

57.6 ± 17.2^†

66.5 ± 17.0

70.2 ± 21.1

58.4 ± 13.5^†

 TLC

69.7 ± 15.1^†

73.1 ± 13.3^†

83.5 ± 11.4

69.3 ± 15.3^†

6MWT (n = 324)

n = 157

n = 107

n = 32

n = 28

 Distance, meter

448.2 ± 110.7

459.5 ± 95.4

475.3 ± 92.2

440.6 ± 110.5

 Initial SpO₂, %

96.0 ± 1.8^†

96.5 ± 1.3^†

97.3 ± 1.1

96.3 ± 1.7^†

 Lowest SpO₂, %

89.5 ± 6.0^†

92.2 ± 4.5

93.5 ± 5.0

89.7 ± 6.2^†

BAL fluid analysis (n = 220)

n = 118

n = 72

n = 15

n = 15

 WBC, /μl

289.2 ± 278.4

305.0 ± 237.2

354.7 ± 305.5

233.5 ± 171.0

 Neutrophil, %

12.0 ± 20.2

8.6 ± 15.3

6.5 ± 5.5

12.9 ± 18.8

 Lymphocyte, %

13.2 ± 12.6

12.0 ± 10.4

15.9 ± 15.9

15.7 ± 13.9

Treatment

 Antifibrotic agents

56 (34.6)

46 (42.2)

12 (36.4)

5 (16.7)

 Steroid ± IM

63 (38.9)

38 (34.9)

8 (24.2)

16 (53.3)

 No treatment

43 (26.5)

25 (22.9)

13 (39.4)

9 (30.0)