Table 1 Characteristics of patients with SSc-ILD never or ever using immunosuppressive therapy

Number of patients

3778

1097 (29%)

2681 (71%)

Age (mean, SD)

55.5 ± 13.4

59.0 ± 13.6

54.0 ± 13.0

<0.001

Female

83.6%

86.5%

82.4%

0.002

BMI (mean, SD) (n = 1901)

24.6 ± 4.7

24.5 ± 5.1

24.7 ± 4.6

n.s.

Duration of SSc, years (mean, SD)

8.5 ± 7.9

10.8 ± 9.2

7.6 ± 7.1

<0.001

(median (IQR))

6.2 (2.8; 11.9)

8.4 (4.3; 15.0)

5.4 (2.4; 10.8)

 (mean, SD)

10.6 ± 8.7

8.9 ± 7.6

11.3 ± 9.0

<0.001

 (median (IQR))

8.0 (4.0; 17.0)

7.0 (4.0; 17.0)

9.0 (4.0; 17.0)

 diffuse

44.4%

29.4%

50.3%

 limited

46.9%

60.9%

41.3%

<0.001

 sclerodactyly only

7.5%

7.4%

7.6%

 none

1.2%

2.4%

0.8%

Present scleroderma pattern (n = 1081)

92.6%

92.3%

92.7%

n.s.

 active

40.7%

41.5%

40.4%

 early

21.1%

25.3%

19.4%

0.076

 late

38.2%

33.2%

40.2%

SSc activity index ≥3 (n = 3557)

20.0%

12.8%

22.9%

<0.001

DLCO, % predicted (mean, SD) (n = 2909)

62.0 ± 20.2

67.4 ± 19.8

59.9 ± 20.0

<0.001

FVC, % predicted (mean, SD) (n = 2239)

87.5 ± 21.8

94.9 ± 20.9

84.4 ± 21.5

<0.001

FVC:DLCO ratio (n = 2072)

1.5 ± 0.5

1.5 ± 0.5

1.5 ± 0.5

n.s.

FEV-1, % predicted (mean, SD) (n = 2239)

86.2 ± 19.9

90.7 ± 19.0

84.2 ± 20.0

<0.001

TLC, % predicted (mean, SD) (n = 2239)

85.0 ± 20.5

90.6 ± 20.1

82.6 ± 20.2

<0.001

 worsening of skin

18.2%

12.5%

20.6%

<0.001

 worsening of fingers

22.7%

20.7%

23.6%

n.s.

 esophageal symptoms

66.2%

65.0%

66.6%

n.s.

 stomach symptoms

25.9%

22.1%

27.5%

<0.001

 intestinal symptoms

24.9%

24.2%

25.2%

n.s.

 arterial hypertension

23.2%

23.7%

23.0%

n.s.

 renal crisis

2.0%

1.7%

2.1%

n.s.

 dyspnoea

17.3%

12.2%

19.4%

<0.001

 worsening of cardiopulmonary manifestations

19.1%

14.8%

20.9%

<0.001

 palpitations

27.9%

23.8%

29.5%

<0.001

 Raynaud’s present

96.7%

96.1%

97.0%

n.s.

 I

44.0%

49.9%

41.6%

 II

38.7%

37.8%

39.0%

<0.001

 III

15.2%

10.1%

17.3%

 IV

2.1%

2.1%

2.1%

 ANA+

94.9%

95.6%

94.6%

n.s.

 ACA+

21.9%

38.6%

15.1%

<0.001

 SCL70+

48.8%

36.4%

53.8%

<0.001

 U1 RNP+

6.4%

2.9%

7.9%

<0.001

 RNA+

4.5%

4.1%

4.7%

n.s.

 PM-Scl+

4.5%

3.7%

4.9%

n.s.

 CRP elevation

27.5%

18.5%

31.3%

<0.001

 CK elevation

9.3%

5.8%

10.7%

<0.001

 Proteinuria

6.4%

5.7%

6.7%

n.s.

 Hypocomplementemia

6.0%

4.9%

6.4%

n.s.

 ESR mm/h (mean, SD)

25.8 ± 20.7

23.7 ± 17.6

26.7 ± 21.7

0.048

Conduction blocks (n = 3451)

14.1%

12.8%

14.6%

n.s.

Pulmonary hypertension (n = 3451)

23.2%

22.7%

23.3%

n.s.

Diastolic function abnormal (n = 3363)

24.3%

21.1%

25.5%

0.008

Pericardial effusion (n = 2227)

12.6%

13.2%

12.4%

n.s.

Ground glass opacification (n = 2014)

41.1%

30.3%

45.5%

<0.001

PFT restrictive defect (n = 3457)

45.9%

35.6%

49.9%

<0.001

Echo

LVEF (%) (n = 2095)

61.4 ± 6.2

62 ± 6.6

61.8 ± 6.5

0.005

PAPsys (mmHg) (n = 1835)

33 ± 14.9

32.4 ± 12.7

32.6 ± 13.4

n.s.

Right heart catheter

RVSP (mmHg) (n = 96)

46.8 ± 21.9

40.5 ± 17.9

42.5 ± 19.3

n.s.

PAPmean (mmHg) (n = 146)

36.2 ± 15.4

28.5 ± 12.0

30.8 ± 13.5

0.003

PVR (dyn · sec · cm-5) (n = 94)

541.5 ± 498

213.5 ± 258.1

328.6 ± 391.2

0.001

PWP (mmHg) (n = 113)

12.1 ± 7.0

12.2 ± 9.6

12.2 ± 9.0

n.s.

CI (l/min/m2) (n = 100)

2.8 ± 0.6

3.3 ± 1.1

3.1 ± 1.0

0.021

6 MWD

6 MWD (m) (n = 551)

444.9 ± 129.6

421.3 ± 123.8

428.1 ± 125.9

0.021

O2 saturation at rest (n = 457)

96 ± 6.3

95.9 ± 4.3

96.0 ± 5.0

n.s.

O2 saturation at exercise (n = 389)

92.9 ± 8.0

92.2 ± 8.0

92.4 ± 8.0

n.s.