Table 1. Baseline patient characteristics.
| * | SPRA (n = 201) | SNRA (n = 40) | p value |
|---|---|---|---|
| Age (mean±SD, years) | 56.5±15.1 | 58.2±14.5 | 0.513 |
| Female [n(%)] | 149 (74.1) | 27 (67.5) | 0.436 |
| Disease duration (mean±SD, months) | 11.1±25.1 | 6.3±15.5 | 0.252 |
| Follow-up duration (mean±SD, months) | 31.6±21.9 | 27.1±24.3 | 0.248 |
| RF positive [n(%)] | 190 (94.5) | ||
| ACPA positive [n(%)] | 193 (96) | ||
| Proportion of patients meeting 1987 criteria | 118 (58.7) | 39 (97.5) | <0.001 |
| Proportion of patients meeting 2010 criteria | 200 (99.5) | 11 (27.5) | <0.001 |
| 28 TJC (mean±SD) | 3.3±2.7 | 4.7±2.9 | 0.004 |
| 28 SJC (mean±SD) | 2.9±2.3 | 4.3±3.0 | 0.001 |
| ESR (mean±SD, mm/hr) | 55.2±32.2 | 55.9±39.6 | 0.903 |
| CRP (mean±SD, mm/hr) | 2.5±3.9 | 3.6±5.2 | 0.135 |
| DAS28-ESR (mean±SD) | 4.7±1.0 | 5.1±1.0 | 0.043 |
Statistical method:
*Student’s t-test, SPRA: seropositive rheumatoid arthritis, SNRA: seronegative rheumatoid arthritis, SD: standard deviation, RF: rheumatoid factor, ACPA: anti-cyclic citrullinated peptide antibody, TJC: tender joint count, SJC: swollen joint count, ESR: erythrocyte sedimentation area, CRP: C-reactive protein, DAS28-ESR: disease activity score 28 base on ESR value