Table 1 Baseline characteristics of CTD-PAH patients

n = 74

n = 73

Gender,n(%)

 Male

2 (2.7%)

5 (6.9%)

 Female

72 (97.3%)

68 (93.2%)

Age,years

39.6 (33.7–50.5)

47.1 (32.1–57.0)

CTD,n(%)

 SLE

26 (35.1%)

20 (27.4%)

 OS

19 (25.7%)

20 (27.4%)

 SS

12 (16.2%)

18 (24.7%)

 SSc

6 (8.1%)

8 (11.0%)

 UCTD

3 (4.1%)

5 (6.9%)

 MCTD

5 (6.8%)

1 (1.4%)

 RA

3 (4.1%)

1 (1.4%)

CTD duration,months

31.50(0.17–91.50)

0.90(0.00–92.40)

NT-proBNP,pg/mL

202 (102–598)

2094 (786–4360)

6MWD,m

465 (400–525)

386 (291–460)

WHO class,n(%)

 I-II

53 (71.6%)

23 (31.9%)

 III-IV

21 (28.4%)

49 (68.1%)

PAH therapy,n(%)

 None

2 (2.7%)

2 (2.7%)

 Monotherapy

23 (31.1%)

16 (21.9%)

 Combination therapy

49 (66.2%)

55 (75.3%)

 Glucocorticoid,n(%)

68 (91.9%)

63 (86.3%)

 Immunosuppressant,

n(%)

49 (66.2%)

54 (75.0%)

 Diuretic,n(%)

13 (33.3%)

23 (54.8%)

Laboratory examination

 ALT,U/L

17.80 (12.90–29.40)

19.60 (13.40–35.40)

 AST,U/L

25.40 (19.10–35.00)

31.70 (22.70–40.00)

 BUN,mmol/L

5.30 (4.00–6.49)

6.11 (4.98–8.51)

 Cr,μmol/L

52.20 (47.20–60.80)

66.60 (56.20–81.40)

 UA,μmol/L

317.00 (244.00–386.00)

404.00 (329.00–508.00)

 ESR,mm/h

22.00 (8.00–52.50)

21.00 (10.00–55.80)

RF,IU/mL,n(%)

  < 20.0

37 (56.9%)

45 (67.2%)

  ≥ 20.0

28 (43.1%)

22 (32.8%)

 CRP,mg/L

3.62 (2.13–8.93)

3.59 (2.97–10.7)

 IgG,g/L

15.70 (11.40–22.70)

12.70 (10.10–19.00)

 IgA,g/L

2.60 (1.97–3.38)

2.49 (1.86–3.38)

 IgM,g/L

1.18 (0.70–1.70)

0.97 (0.60–1.52)

 C3,g/L

0.74 ± 0.26

0.77 ± 0.24

 C4,g/L

0.14 (0.10–0.18)

0.16 (0.12–0.20)

 TnI( +),n(%)

11 (26.2%)

4 (8.7%)