Skip to main content

Table 1 Demographic characteristics of the patient population

From: Type I interferon in patients with systemic autoimmune rheumatic disease is associated with haematological abnormalities and specific autoantibody profiles

 

Whole cohort (n = 164)

ISG negative (n = 101)

ISG positive (n = 63)

p value (ISG positive vs. negative)

Age (years)

48.5 (36.8, 57.3)

50.3 (40.6, 59.5)

44.8 (31.6, 52.8)

0.012

Gender, female

155 (94.5)

97 (96.0)

58 (92.1)

0.277

Disease duration (years) n = 158

7.11 (3.16, 15.8)

6.84 (3.06, 15.3)

8.08 (3.56, 16.1)

0.538

Age at disease onset (years)

36.5 (26.2, 47.4)

40.5 (30.1, 48.4)

31.6 (23.6, 41.1)

0.005

Ethnicity

 Caucasian

122 (74.8)

80 (79.2)

42 (66.7)

0.430

 Mixed

1 (0.6)

1 (0.99)

0

 Asian or Asian British

8 (4.9)

3 (2.97)

5 (7.94)

 Black or Black British

24 (14.6)

12 (11.9)

12 (19.0)

 Other

10 (6.1)

4 (3.96)

4 (6.35)

 Unknown

1

1 (0.99)

0

Disease group

 UCTD

43 (26.2)

34 (33.7)

9 (14.3)

< 0.0001

 SLE

67 (40.9)

40 (39.6)

27 (42.9)

 MCTD

13 (7.93)

4 (3.96)

9 (14.3)

 SS

20 (12.2)

6 (5.94)

14 (22.2)

 IIM

8 (4.88)

6 (5.94)

2 (3.17)

 SSc

13 (7.93)

11 (10.9)

2 (3.17)

Concomitant medication use

 Oral prednisolone

45 (27.3)

28 (27.7)

17 (27.0)

0.918

 Anti-malarial*

96 (58.5)

64 (63.4)

32 (50.8)

0.112

 Immunosuppressant**

47 (28.7)

28 (27.7)

19 (30.2)

0.737

 Biological agent (within 6 months)

2 (1.22)

2 (1.98)

0

0.261

 Daily dose prednisolone (mg)

7.5 (5.0, 10)

7.5 (5.0, 10)

7.5 (6.25, 10)

0.552

Autoantibodies

 dsDNA

46 (28.0)

24 (23.8)

22 (34.9)

0.122

 Ro/SS-A

49 (29.9)

18 (17.8)

31 (49.2)

< 0.0001

 La/SS-B

23 (14.0)

9 (8.91)

14 (22.2)

0.017

 Smith

23 (14.0)

5 (4.95)

18 (28.6)

< 0.0001

 RNP

39 (23.8)

13 (12.9)

26 (41.3)

< 0.0001

 Chromatin

33 (20.1)

9 (8.91)

24 (38.1)

< 0.0001

 Rheumatoid factor

37 (22.6)

12 (11.9)

25 (29.7)

< 0.0001

 CCP

7 (4.3)

3 (2.97)

4 (6.35)

0.298

 SSC-specific†

15 (9.1)

11 (10.9)

4 (6.35)

0.326

 Jo-1

4 (2.4)

3 (2.97)

1 (1.59)

0.577

Clinical features

 Photosensitivity

64 (39.3)

43 (42.6)

21/62 (33.9)

0.174

 Myositis-specific rash

10 (6.10)

7 (6.93)

3 (4.76)

0.419

 Discoid lesion

6 (3.68)

3 (2.97)

3/62 (4.84)

0.414

 Mucosal ulcers

63 (38.7)

41 (40.6)

22/62 (35.5)

0.315

 Raynaud’s syndrome

87 (53.4)

55 (54.5)

32/62 (51.6)

0.424

 Inflammatory arthritis

75 (46.0)

42/100 (42.0)

33 (52.4)

0.129

 Renal disease‡

24 (14.9)

13/99 (13.1)

11/62 (17.7)

0.281

 Neurological disease ‡

4 (2.44)

2 (1.98)

2 (3.17)

0.498

 Haematological disorder‡

74 (46.3)

35/99 (35.4)

39/61 (63.9)

< 0.0001

  1. Data are shown as the n(%) or median (IQR). ISG = interferon-stimulated gene
  2. *Hydroxychloroquine, mepacrine or chloroquine phosphate
  3. **Azathioprine, methotrexate, mycophenolate mofetil, ciclosporine, tacrolimus
  4. †Anti-Scl70, anti-centromere and anti-RNA-polymerase III
  5. ‡As the per modified 1997 ACR Classification criteria for SLE