Skip to main content

Table 1 Baseline characteristics of the study population

From: Clinical characteristics and survival of pulmonary arterial hypertension with or without interstitial lung disease in systemic sclerosis

Variable

 

Disease groupa

n (%) or mean

 

Cohort overall

(n = 1561)

PAH-ILD

(n = 107)

PAH-only

(n = 112)

ILD-only

(n = 372)

SSc-only

(n = 970)

p-value

Female

1349 (86.4%)

83 (77.6%)

98 (87.5%)

308 (82.8%)

860 (88.7%)

0.001

Race

 Caucasian

1345 (90.9%)

90 (88.2%)

98 (94.2%)

296 (83.2%)

861 (93.9%)

 < 0.001

 Asian

80 (5.4%)

9 (8.8%)

2 (1.9%)

42 (11.8%)

27 (2.9%)

 

 Aboriginal-Torres Strait Islander

17 (1.2%)

1 (1.0%)

2 (1.9%)

6 (1.7%)

8 (0.9%)

 

 Hispanic

12 (0.8%)

0 (0.0%)

2 (1.9%)

2 (0.6%)

8 (0.9%)

 

 Other

25 (1.7%)

2 (2.0%)

0 (0.0%)

10 (2.8%)

13 (1.4%)

 

Age of SSc onset (years)b

47.1 (36.2–56.4)

50.5 (42.6–60.2)

51.2 (41.4–61.5)

47.1 (35.0–56.2)

45.9 (35.6–55.2)

 < 0.001

Disease duration at recruitment (years)b

7.5 (2.5–15.9)

7.8 (2.8–17.9)

10.8 (4.2–20.5)

6.4 (2.1– 14.3)

7.8 (2.5–15.7)

0.017

Diffuse skin disease

404 (25.9%)

36 (34.0%)

13 (11.6%)

138 (37.0%)

217 (22.4%)

 < 0.001

Overlap CTD

127 (13.4%)

6 (8.0%)

5 (7.7%)

37 (15.0%)

79 (14.1%)

0.212

 Rheumatoid arthritis

54 (3.5%)

1 (0.9%)

3 (2.7%)

15 (4.0%)

35 (3.6%)

0.36

 SLE

18 (1.2%)

0 (0.0%)

1 (0.9%)

6 (1.6%)

11 (1.1%)

0.61

 Polymyositis

26 (1.7%)

2 (1.9%)

0 (0.0%)

11 (3.0%)

13 (1.3%)

0.22

 Sjögren syndrome

37 (2.4%)

4 (3.7%)

0 (0.0%)

10 (2.7%)

23 (2.4%)

0.29

Follow-up (years)

3.5 (1.0–7.1)

4.0 (2.0–7.7)

3.6 (1.0–6.9)

4.1 (1.2–8.2)

3.3 (1.0–6.7)

0.003

Deceased

232 (14.9%)

54 (50.5%)

53 (47.3%)

60 (16.2%)

65 (6.7%)

 < 0.001

Ever smoked*

752 (48.6%)

46 (43.8%)

54 (50.0%)

154 (41.6%)

498 (51.6%)

0.008

Comorbidities (CCI score)*

2 (1–3)

3 (2–4)

3 (2–4)

2 (1–3)

2 (1–3)

 < 0.001

Antibody profile

ANA centromere positive (n = 1486)

694 (46.7%)

26 (25.7%)

86 (79.6%)

61 (17.2%)

521 (56.5%)

 < 0.001

ENA subtype

 Anti-Scl-70 (n = 1463)

230 (15.7%)

17 (16.8%)

1 (1.0%)

135 (38.5%)

77 (8.5%)

 < 0.001

 Anti-RNP (n = 1461)

96 (6.6%)

6 (5.9%)

7 (6.7%)

31 (8.9%)

52 (5.8%)

0.256

 Anti-Ro60 (n = 1459)

127 (8.7%)

17 (16.7%)

11 (10.7%)

44 (12.6%)

55 (6.1%)

 < 0.001

 Anti-La (n = 1456)

22 (1.5%)

3 (3.0%)

2 (1.9%)

6 (1.7%)

11 (1.2%)

0.533

Anti-dsDNA (n = 1235)

92 (7.3%)

6 (6.3%)

6 (6.7%)

25 (7.8%)

55 (7.3%)

0.964

RNA polymerase III (n = 1103)

151 (13.7%)

17 (21.0%)

4 (5.0%)

33 (12.0%)

97 (14.5%)

0.021

ANCA (n = 1396)

221 (15.8%)

26 (27.7%)

10 (10.3%)

78 (23.2%)

107 (12.3%)

 < 0.001

MPO-ANCA (n = 1390)

25 (1.8%)

1 (1.1%)

0 (0.0%)

12 (3.6%)

12 (1.4%)

0.031

PR3-ANCA (n = 1390)

32 (2.3%)

4 (4.3%)

1 (1.0%)

9 (2.7%)

18 (2.1%)

0.433

Antiphospholipid antibodies (n = 1378)

360 (26.1%)

33 (34.4%)

32 (32.7%)

96 (29.3%)

199 (23.3%)

0.012

  1. Abbreviations: ANA antinuclear antibody, ANCA anti-neutrophil cytoplasmic antibodies, ASCS Australian Scleroderma Cohort Study, CCI Charlson Comorbidity Index, CCP cyclic citrullinated peptide, CTD connective tissue disease, dsDNA double-stranded deoxyribonucleic acid, ENA extractable nuclear antigen, ILD interstitial lung disease, MPO myeloperoxidase, n number, PAH pulmonary arterial hypertension, PR3 proteinase-3, RNA ribonucleic acid, RNP ribonucleoprotein, SLE systemic lupus erythematosus, Sm Smith, SSc systemic sclerosis
  2. aFour mutually exclusive disease groups based on presence of concurrent PAH and ILD (PAH-ILD), PAH alone (PAH-only), ILD alone (ILD-only) or neither comorbidity (SSc-only)
  3. bTime from first symptom other than Raynaud’s phenomenon
  4. *Comorbidities defined by the modified Charlson Comorbidity Index Score
Back to article page

Arthritis Research & Therapy

ISSN: 1478-6362

Contact us