Differences in baseline characteristics between sIL-6R-low and sIL-6-high patients
| Characteristics | All (n=43) | Baseline sIL-6R | ||
|---|---|---|---|---|
| sIL-6R-low (n=19) | sIL-6R-high (n=24) | p Value | ||
| Age, years | 60 (52–67) | 57 (45–66) | 61 (53–70) | 0.33 |
| Gender, female, n (%) | 38 (88) | 17 (89) | 21 (88) | 1.00 |
| Disease duration, years | 4.5 (2.2–7.9) | 5.2 (3.7–7.9) | 3 (1.8–8.0) | 0.47 |
| Concomitant methotrexate, n (%) | 14 (33) | 5 (26) | 9 (38) | 0.52 |
| Methotrexate dose, mg/week | 8 (7.1–10) | 8 (6–9) | 8 (7.75–10) | 0.36 |
| Glucocorticoid use, n (%) | 14 (33) | 5 (26) | 9 (38) | 0.52 |
| DAS28-ESR | 5.1 (4.2–5.9) | 4.77 (3.94–6.05) | 5.16 (4.46–5.78) | 0.51 |
| SDAI | 19.78 (14.85–27.99) | 19.78 (12.45–27.99) | 19.79 (15.32–28.13) | 0.59 |
| CDAI | 18.3 (13.8–25.2) | 18.3 (11.8–26.7) | 18.1 (14.2–25.0) | 0.73 |
| TJC, 28 joints | 5 (3–6) | 4 (2–6) | 5 (3–7.75) | 0.32 |
| SJC, 28 joints | 5 (3–8) | 5 (3–9) | 5 (3–7.5) | 0.61 |
| Patient global VAS, mm | 45 (23–65) | 39 (15–70) | 46 (35–64) | 0.35 |
| Physician global VAS, mm | 41 (26–59) | 39 (32–55) | 45 (25–60) | 0.62 |
| CRP, mg/dL | 0.49 (0.13–2.80) | 0.45 (0.17–2.21) | 0.57 (0.13–3.20) | 0.41 |
| ESR, mm/h | 46 (19–65) | 46 (18–59) | 46 (19–69) | 0.85 |
| HAQ-DI | 1 (0.500–1.250) | 1 (0.375–1.500) | 1 (0.500–1.125) | 0.96 |
| RF value, IU/mL | 68 (27–121) | 71 (28–106) | 65 (17–150) | 0.95 |
| Anti-CCP antibody value, IU/mL | 141 (17–>300) | 94 (19–>300) | 238 (16–>300) | 0.49 |
| MMP-3 value, ng/mL | 104 (60–219) | 68 (51.5–260) | 113 (60–218) | 0.77 |
| IL-6, pg/mL | 4.70 (1.51–8.54) | 1.82 (1.15–13.2) | 5.99 (2.88–8.35) | 0.28 |
Data are shown as median (IQR) or number of patients (%). Statistical differences between median values were analysed by Wilcoxon rank-sum test. Differences in percentage values were analysed by Fisher's exact test.
CCP, cyclic citrullinated peptide; CDAI, clinical disease activity index; CRP, C-reactive protein; DAS28, disease activity score with 28 joint counts; ESR, erythrocyte sedimentation rate; HAQ-DI, health assessment questionnaire–disability index; IL, interleukin; MMP-3 matrix metalloproteinase 3; RF, rheumatoid factor; SDAI, simplified disease activity index; sIL-6R, soluble interleukin-6 receptor; SJC, swollen joint count; TJC, tender joint count; VAS, visual analogue scale.