Table 1. Clinical characteristics and laboratory findings in patients with active rheumatoid arthritis (RA), inactive RA, patients with knee osteoarthritis (OA) and healthy controls (HC).
| Active RA (n = 22) | Inactive RA (n = 16) | Knee OA (n = 12) | HC (n = 10) | |
| Mean age (years) | 50.3±10.4 | 56.9±17.5 | 58.3±5.6 | 52.0±8.3 |
| Female (%) | 18 (81.8%) | 12 (75.0%) | 10 (83.3%) | 7 (70.0%) |
| RF positivity (%) | 16 (72.7%) | 12 (75.0%) | NA | NA |
| Anti-CCP positivity (%) | 15 (68.2%) | 10 (62.5%) | NA | NA |
| CRP (mg/dl) | 2.54±1.91* | 0.43±0.25 | NA | NA |
| DAS-28 | 4.94±0.95* | 2.90±0.30 | NA | NA |
| Daily steroid dose (mg) | 5.2±2.0* | 2.5±1.3 | NA | NA |
| DMARDs used | ||||
| Methotrexate | 19 (86.4%) | 11 (68.8%) | NA | NA |
| Sulfasalazine | 17 (77.3%) | 10 (62.5%) | NA | NA |
| Hydroxychloroquine | 16 (72.7%) | 8 (50.0%) | NA | NA |
| Cyclosporine | 4 (18.2%) | 0 (0.0%) | NA | NA |
Data are presented as mean ± SD or number (percentage); NA: not applicable.
RF: rheumatoid factor; Anti-CCP: anti-cyclic citrullinated peptide antibodies; CRP: C-reactive protein; DAS28: disease activity score for 28-joints; DMARDs: disease-modifying anti-rheumatic drugs.
A result was considered positive for RF when the concentration was ≧15 IU/ml; a result was considered positive for anti-CCP antibodies if the titer was≧20 IU/ml. *p<0.001, versus inactive RA group, determined using the Mann-Whitney U test.