Table 2 Characteristics of patients in the NR, SR and RR latent classes in the whole cohort

Age group (years)

0.669

 <35

119 (29.1%)

72 (28.9%)

117 (26.5%)

 35–55

230 (56.4%)

133 (53.4%)

247 (56.0%)

 >55

59 (14.5%)

44 (17.7%)

77 (17.5%)

Female

387 (94.9%)

237 (95.2%)

412 (93.4%)

0.542

Disease duration (years)

6.04 (2.17, 13.3)

5.17 (1.92. 12.4)

5.33 (1.75, 12.3)

0.373

ACR/SLICC-DI

0 (0, 2)

0 (0, 2)

0 (0, 2)

0.905

SLEDAI-2K

9.5 (8, 12)

10 (8, 12)

10 (8, 12)

0.394

nBILAG score

17 (16, 21)

20 (16, 25)

20 (16, 25)

<0.001

BILAG 2004 A or B score

 Constitutional

15 (3.68%)

26 (10.4%)

59 (13.4%)

<0.001

 Mucocutaneous

335 (82.1%)

212 (85.1%)

362 (82.1%)

0.535

 Musculoskeletal

365 (89.5%)

237 (95.2%)

425 (96.4%)

<0.001

 Cardiorespiratory

25 (6.13%)

25 (10.0%)

63 (14.3%)

<0.001

 Gastrointestinal

3 (0.74%)

6 (2.41%)

8 (1.81%)

0.203

 Ophthalmological

4 (0.98%)

2 (0.8%)

6 (1.36%)

0.766

 Haematological

5 (1.23%)

2 (0.80%)

5 (1.13%)

0.875

Serology

 Anti-Ro

198 (48.8%)

108 (44.8%)

207 (47.5%)

0.621

 Anti-RNP

109 (26.9%)

61 (25.3%)

142 (32.6%)

0.074

 Anti-dsDNA

107 (26.3%)

63 (26.1%)

123 (28.3%)

0.759

 Anti-dsDNA level* (IU/ml) (n=314)

291 (181, 456)

261 (175, 491)

291 (185, 544)

0.618

 Anti-Smith (Sm)

96 (23.7%)

59 (24.5%)

117 (26.8%)

0.548

 Low C3 level

129 (32.3%)

78 (32.0%)

143 (32.9%)

0.966

 C3 level (g/l)

1.08 (0.84, 1.30)

1.06 (0.85, 1.27)

1.08 (0.83, 1.28)

0.803

 Low C4 level

165 (41.3%)

88 (36.1%)

181 (41.6%)

0.320

 C4 level (mg/l)

200 (120, 300)

220 (150, 300)

200 (130, 310)

0.591

Epratuzumab (either dose)

252 (61.8%)

170 (68.3%)

300 (68.0%)

0.100

Baseline steroid dose (mg/day)

9.5 (5, 10)

10 (5, 15)

10 (5, 15)

0.0418

Cumulative steroid exposure (mg days)

2247.5 (1532.5, 3500)

2685 (1750, 4062.5)

2360 (1685, 3610)

0.0027

Concomitant therapy

 Anti-malarial

279 (72.8%)

187 (75.1%)

327 (74.2%)

0.795

 Methotrexate

84 (20.6%)

55 (22.1%)

94 (21.3%)

0.899

 Leflunomide

9 (2.21%)

6 (2.41%)

17 (3.85%)

0.312

 Azathioprine

116 (28.4%)

73 (29.3%)

104 (23.8%)

0.158

 Mycophenolate mofetil

44 (10.8%)

29 (11.7%)

54 (12.4%)

0.801

Withdrawal (lack of efficacy)

84 (20.6%)

19 (7.63%)

37 (8.93%)

<0.001

Withdrawal (adverse events)

24 (5.88%)

14 (5.62%)

29 (6.58%)

0.853