Table 1 Comparison of demographic and clinical variables between familial and sporadic PF patients

Mean age symptom onset

57.11

57.97

N/A

63.85

p = 0.012

(years)

(FPF-DC vs. sporadic)

Mean age at diagnosis (years)

60.65

61.43

58.45

66.58

p = 0.012

(FPF-DC vs. sporadic)

Mean age at death or

N/C

64.58 (n = 36)

73.62 (n = 6)

70.60 (n = 32)

p = 0.025

transplant (n = number of deceased or transplanted patients)

(FPF-DC vs. sporadic)

Gender

Number (%) males

M = 43 (55.8 %)

M = 34 (59.6 %)

M = 9 (45.0 %)

M = 31 (62.0 %)

p = 0.531

Number (%) females

F = 34 (44.2 %)

F = 23 (40.4 %)

F = 11 (55.0 %)

F = 19 (38.0 %)

(total FPF vs. sporadic)

Current or ever smokers (%)

61/76 (80.3 %)

45/56 (80.4 %)

16/20 (80.0 %)

42/50 (84.0 %)

p = 0.767

(total FPF vs. sporadic)

Number of patients with symptom at diagnosis:

FPF-DC vs. sporadic

Dyspnea

N/C

43 (75.4 %)

N/C

44 (88.0 %)

p = 0.096

Cough

37 (64.9 %)

35 (70.0 %)

p = 0.576

Chest pain

14 (24.6 %)

12 (24.0 %)

p = 0.946

Pneumonia

10 (17.5 %)

7 (14.0 %)

p = 0.617

Hemoptysis

5 (8.8 %)

1 (2.0 %)

p = 0.129

Pneumothorax

2 (3.5 %)

0 (0.0 %)

p = 0.181

Most specific diagnostic test:

Number of patients (%)

CXR

4 (5.2 %)

4 (7.0 %)

0 (0.0 %)

0 (0.0 %)

HRCT

40 (51.9 %)

23 (40.4 %)

17 (85.0 %)

31 (62.0 %)

Surgical lung biopsy

30 (39.0 %)

28 (49.1 %)

2 (10.0 %)

21 (42.0 %)

Autopsy

3 (3.9 %)

2 (3.5 %)

1 (5.0 %)

0 (0.0 %)

Treatments: Number of patients (%)

FPF-DC vs. sporadic

Prednisone

40 (51.9 %)

38 (66.7 %)

2 (10.0 %)

36 (72.0 %)

p = 0.551

Cyclophosphamide

7 (9.1 %)

7 (12.3 %)

0 (0.0 %)

2 (4.0 %)

p = 0.170

Azathioprine

12 (15.6 %)

11 (19.3 %)

1 (5.0 %)

12 (24.0 %)

p = 0.555

N-acetyl cysteine

16 (20.8 %)

13 (22.8 %)

3 (15.0 %)

20 (40.0 %)

p = 0.055

Lung transplant

5 (6.5 %)

5 (8.8 %)

0 (0.0 %)

3 (6.0 %)

p = 0.586