Table 1 Baseline characteristics of patients with airway-centered interstitial fibrosis (n = 68)

Sex, male/female

29/39

Age, years (mean ± SD)

57 ± 12

Duration of symptoms, in months, median (range)

24 (3–132)

Smoking

Never/ex-smoker/current smoker, n

39/28/1

Dyspnea

Major/moderate/light tasks, n

22/33/13

Coughing, n (%)

53 (78%)

Clubbing, n (%)

12 (18%)

Velcro crackles, n (%)

29 (43%)

Exposure to organic particles, n (%)

42 (62%)

Molds/birds/both

24/ 4/ 14

Gastroesophageal reflux (GERD) symptoms

None/past/current

30/ 12/ 26

Connective tissue disease (CTD), n (%)^†

12 (17%)

Lung function tests

FVC, % predicted (mean ± SD)

66 ± 18

FEV₁, % predicted (mean ± SD)

69 ± 18

FEV₁/FVC, (mean ± SD)

0.85 ± 0,08

DL_CO, % predicted (mean ± SD) (n = 43)

59 ± 17

Oxygen saturation at rest, % (mean ± SD)

94 ± 4

Oxygen saturation during exercise, % (mean ± SD) (n = 59)

87 ± 7

HRCT findings

Reticular infiltrate, n (%)

68 (100%)

Predominance: Upper lobe/lower lobe/diffuse, n

10/38/20

Predominance: Central/peripheral/both, n

9/14/45

Ground-glass opacities, n (%)

57 (84%)

Peribronchovascular, n (%)

54 (79%)

Bronchiectasis, n (%)

43 (63%)

Mosaic pattern/airtrapping, n (%)

25 (37%)

Centrilobular nodules, n (%)

14 (21%)