Table 2 SSc disease features and treatment of the study population

PAH- and ILD-specific features

HRCT performed

107 (100%)

81 (72.3%)

372 (100%)

307 (31.7%)

 < 0.001

ILD severity^b

 < 0.001^#

 Limited

55 (51.4%)

N/A

244 (65.6%)

N/A

 Extensive

48 (44.9%)

N/A

86 (23.1%)

N/A

 Missing

4 (3.7%)

N/A

42 (11.3%)

N/A

Pulmonary function testing^c

 FVC (lowest)

63.0 (51.0–83.0)

85.5 (73.0–97.5)

74.4 (62.0–90.0)

95.0 (84.0–106.0)

 < 0.001

 DLCO (lowest, %)

33.4 (27.0–43.0)

43.2 (33.0–51.9)

51.9 (40.5–63.0)

70.1 (59.2–81.8)

 < 0.001

 Six-minute walk test performed

101 (94.4%)

104 (92.9%)

274 (73.7%)

657 (67.7%)

 < 0.001

 Six-minute walk distance (lowest, m)

280.0 (180.0–384.0)

295.5 (209.0–364.0)

444.0 (360.0–515.0)

465.0 (395.0–536.0)

 < 0.001

WHO functional class (dyspnoea; highest recorded)^c

 Class I

1 (1.0%)

3 (2.8%)

91 (25.4%)

436 (46.9%)

 < 0.001

 Class II

8 (7.8%)

12 (11.3%)

136 (37.9%)

354 (38.1%)

 Class III

58 (55.8%)

67 (63.2%)

116 (32.3%)

131 (14.1%)

 Class IV

37 (35.6%)

24 (22.6%)

16 (4.5%)

8 (0.9%)

Echocardiography

 RVSP (median, mmHg)

47 (39–61.5)

53 (39.5–77.5)

31.5 (27–37)

29 (26–33.5)

 < 0.001, 0.052^

RV dysfunction^c

 Normal RV function

44 (42.3%)

50 (45.9%)

328 (89.9%)

895 (95.6%)

 < 0.001

 Mild

30 (28.9%)

23 (21.1%)

27 (7.4%)

37 (4.0%)

 Moderate

14 (13.5%)

16 (14.7%)

7 (1.9%)

3 (0.3%)

 Severe

16 (15.4%)

20 (18.3%)

3 (0.8%)

1 (0.1%)

Right heart catheter (RHC) at PAH diagnosis or first-recorded value in ILD-only and SSc-only groups

 RHC performed^d

101 (95.3%)

111 (99.1%)

47 (12.6%)

51 (5.3%)

 < 0.001

 RAP (mmHg)

8 (5–10)

8 (6–10)

5 (3–7)

6 (4–10)

0.493^; 0.174^&

 PAWP (mmHg)

10.5 (8–13)

10.5 (8–13)

9 (7–14)

9.5 (7–18)

0.690^; 0.525^&

 Mean PAP (mmHg)

32 (28–41)

33 (27–43.5)

19 (16–23)

19 (15–23)

0.630^; 0.898^&

 PVR (Wood units)

4.5 (2.9–6.8)

4.1 (2.9–6.6)

1.9 (1.3–2.3)

2 (1.2–2.6)

0.919^; 0.899^&

 Cardiac output (L/min)

5.2 (4.1–6.2)

5.1 (4.1–6.3)

5.2 (4.8–5.5)

5.5 (4.7–6.0)

0.976^; 0.150^&

 Cardiac index (L/min/m²)

2.8 (2.5–3.4)

2.5 (2.1–3.4)

2.9 (2.7–3.2)

3.0 (2.7–3.5)

0.176^; 0.430^&

Other SSc disease features and treatment

Disease features

 Raynaud phenomenon^c

107 (100%)

111 (99.1%)

367 (98.7%)

960 (99.0%)

0.682

 Modified Rodnan skin score (highest)^c

10.0 (5.0–19.0)

9.0 (5.0–15.0)

10.0 (6.0–19.0)

7.0 (4.0–14.0)

 < 0.001

 Digital ulcers^c

70 (65.4%)

65 (58.0%)

209 (56.2%)

462 (47.6%)

 < 0.001

 Non-hand skin ulcers^c

10 (9.4%)

12 (10.7%)

55 (14.8%)

69 (7.1%)

 < 0.001

 Calcinosis requiring antibiotics or surgery^c

7 (6.5%)

5 (4.5%)

13 (3.5%)

47 (4.9%)

 < 0.001

 Synovitis^c

44 (41.1%)

35 (31.3%)

157 (42.2%)

364 (37.5%)

0.148

 Myositis^c

4 (3.7%)

1 (0.9%)

17 (4.6%)

17 (1.8%)

0.014

 Dry eyes^c

66 (61.7%)

82 (73.2%)

231 (62.1%)

608 (62.7%)

 < 0.001

 Dry mouth^c

84 (78.5%)

92 (82.1%)

276 (74.2%)

679 (70.0%)

 < 0.001

 Reflux symptoms^c

85 (79.4%)

83 (74.1%)

321 (86.3%)

786 (81.0%)

0.022

 Dysphagia^c

56 (52.3%)

58 (51.8%)

186 (50.0%)

417 (43.0%)

0.008

 Vomiting^c

30 (28.0%)

29 (25.9%)

82 (22.0%)

194 (20.0%)

0.016

 GAVE^c

9 (8.4%)

15 (13.4%)

33 (8.9%)

91 (9.4%)

0.512

 Scleroderma renal crisis^c

7 (6.5%)

1 (0.9%)

7 (1.9%)

28 (2.9%)

0.040

 Highest CRP^c

11.5 (5.3–25)

7.8 (5–20)

7 (4–15)

5 (2.7–9)

 < 0.001

 Highest ESR^c

35.0 (22.0–51.0)

28.0 (15.0–49.0)

28.0 (16.0–42.5)

19.0 (10.0–31.0)

 < 0.001

 Serum CK (highest recorded)^c

112 (61–178)

88 (61–131)

113 (75–175)

100 (72–146)

0.002

 Haemoglobin (lowest recorded)^c

116 (106–131)

116 (106–128)

124 (113–132)

127 (119–135)

 < 0.001

PAH-specific treatments

 Any vasodilator therapy^c

97 (90.7%)

110 (98.2%)

0 (0%)

0 (0%)

 < 0.001; 0.014^

 PDE5^c

64 (59.8%)

67 (59.8%)

0 (0%)

0 (0%)

 < 0.001; 0.999^

 ERA^c

87 (81.3%)

104 (92.9%)

0 (0%)

0 (0%)

 < 0.001; 0.016^

 Prostacyclin analogues^c

6 (5.6%)

14 (12.5%)

0 (0%)

0 (0%)

 < 0.001; 0.080^

 Monotherapy^c

50 (46.7%)

61 (54.5%)

0 (0%)

0 (0%)

 < 0.001; 0.252^

 ERA^c

60 (56.1%)

77 (68.8%)

0 (0%)

0 (0%)

 < 0.001; 0.053^

 PDE5^c

21 (19.6%)

21 (18.8%)

0 (0%)

0 (0%)

 < 0.001; 0.869^

 PCA^c

2 (1.9%)

2 (1.8%)

0 (0%)

0 (0%)

 < 0.001; 0.963^

 Dual therapy^c

46 (43.0%)

40 (35.7%)

0 (0%)

0 (0%)

 < 0.001; 0.270^

 ERA and PDE5^c

44 (41.1%)

39 (34.8%)

0 (0%)

0 (0%)

 < 0.001; 0.337^

 ERA and PCA^c

1 (0.9%)

1 (0.9%)

0 (0%)

0 (0%)

0.006; 0.974^

 PDE5 and PCA^c

1 (0.9%)

0 (0.0%)

0 (0%)

0 (0%)

0.004; 0.305^

 Triple therapy^c

1 (0.9%)

9 (8.0%)

0 (0%)

0 (0%)

 < 0.001; 0.012^

 Lung transplantation^c

1 (0.9%)

1 (0.9%)

4 (1.1%)

0 (0.0%)

0.019

Other treatments

 PPI^c

91 (85.1%)

98 (87.5%)

326 (87.6%)

763 (78.7%)

 < 0.001

 H2 antagonist^c

25 (23.6%)

26 (23.2%)

94 (25.3%)

219 (22.6%)

0.735

 Promotility agents^c

11 (10.4%)

14 (12.5%)

70 (18.8%)

152 (15.7%)

0.131

 Prednisolone^c

69 (64.5%)

30 (26.8%)

222 (59.7%)

354 (36.5%)

 < 0.001; 0.299^#

 Methotrexate^c

19 (17.9%)

9 (8.0%)

99 (26.6%)

231 (23.8%)

 < 0.001; 0.076^#

 Azathioprine^c

19 (17.8%)

1 (0.9%)

80 (21.5%)

38 (3.9%)

 < 0.001; 0.429^#

 Mycophenolate^c

26 (24.3%)

5 (4.5%)

107 (28.8%)

56 (5.8%)

 < 0.001; 0.399^#

 Leflunomide^c

2 (1.9%)

0 (0.0%)

5 (1.3%)

12 (1.2%)

0.609

 Cyclophosphamide^c

18 (16.8%)

5 (4.5%)

80 (21.5%)

26 (2.7%)

 < 0.001; 0.314^#

 Hydroxychloroquine^c

18 (17.0%)

15 (13.4%)

92 (24.7%)

220 (22.7%)

0.043

 TNF-alpha inhibitors^c

1 (0.9%)

1 (0.9%)

5 (1.3%)

7 (0.7%)

0.762

 Rituximab^c

2 (1.9%)

0 (0.0%)

12 (3.2%)

6 (0.6%)

0.001; 0.473^#

 Tocilizumab^c

0 (0.0%)

0 (0.0%)

7 (1.9%)

4 (0.4%)

0.018; 0.155^#

 Abatacept^c

0 (0.0%)

0 (0.0%)

3 (0.8%)

1 (0.1%)

0.120