Table 1 Clinical characteristics of the study participants who underwent bronchoalveolar lavage

No.

40

100

22

20

19

Age (year)

55 (35–72)

63.8 (32–86)*

60.1 (39–70)

51.3 (28–70)

43.3 (28–69)

Sex (male/female)

14/26

63/37

9/13

10/10

10/9

Smoking (CS/ES/NS)

9/12/19

22/29/44

2/5/12

3/3/12

5/2/9

Follow-up duration (years)

ND

4.1 (2.1–6.3)

ND

ND

ND

FVC (% pred.)

106.1 (87.0–119)

75.0 (63.7–83.0)*

78.0 (66.0–91.8)*

64.5 (57.0–82.5)*

77.0 (65.0–86.0)*

FEV1 (% pred.)

102.1 (88.2–117)

89.0 (77.5–100.5)*

85.0 (73.8–101.3)*

74.5 (64.3–92.0)*

85.0 (64.0–101.0)*

DLCO (% pred.)

NA

64.0 (38.5–72.5)*

76.0 (59.0–92.0)*

67.0 (55.0–90.0)*

75.5 (57.8–84.5)*

dFVC (%/year)

NA

−7.0 (−16.5–0.0)

NA

NA

NA

BAL total cell count (10⁴/mL)

3.46 ± 0.82

8.83 ± 2.09*

17.64 ± 3.86*

13.03 ± 3.78*

8.45 ± 3.78*

Macrophages (10⁴/mL)

3.02 ± 0.41

7.37 ± 1.61*

11.51 ± 3.07*

8.25 ± 2.38*

6.76 ± 3.79*

Neutrophils (10⁴/mL)

0.21 ± 0.047

1.35 ± 0.40*

2.31 ± 1.01*^,***

3.14 ± 2.36*^,***

0.45 ± 0.16*^,***

Eosinophils (10⁴/mL)

0.02 ± 0.006

0.48 ± 0.16*

0.45 ± 0.14*

0.41 ± 0.19*

0.11 ± 0.07*

Lymphocytes (10⁴/mL)

0.02 ± 0.006

0.17 ± 0.65*

2.68 ± 0.14*^,**

2.20 ± 0.19*^,**

2.17 ± 0.24*^,**