Table 1.
Characteristics of study patients
| UA>>UA, n=16 | RA, n=19 | UA>>RA, n=8 | SpA, n=7 | |
|---|---|---|---|---|
| Age, years | 39 (20–67) | 53 (22–82) | 54 (43–66) | 44 (20–56) |
| Female, n | 12 | 10 | 7 | 0 |
| Disease duration, months | 4 (1–10) | 5 (1–12) | 4 (1–11) | 2 (1–12) |
| VAS, 0–100 | 63 (9–93) | 37 (11–99) | 48 (32–98) | 35 (17–91) |
| TJC68, n | 3 (0–37) | 16 (5–38) | 13 (3–25) | 4 (0–11) |
| SJC66, n | 1 (1–19) | 8 (4–41) | 6 (1–20) | 2 (1–5) |
| ESR, mm/h | 34 (4–85) | 32 (3–91) | 30 (14–77) | 11 (3–47) |
| CRP, mg/litre | 11 (2–58) | 12 (3–133) | 173–42 | 7 (1–46) |
| IgM-RF positive, n | 2 | 13 | 1 | 0 |
| ACPA positive, n | 2 | 10 | 3 | 0 |
| No DMARDs | 12 | 0 | 0 | 2 |
| DMARD monotherapy | 3 | 15 | 4 | 5 |
| ≥2 DMARDs | 1 | 4 | 2 | 0 |
| ≥2 MTX plus anti-TNF | 0 | 0 | 2 | 0 |
Patients were classified as having rheumatoid arthritis (RA) based on 1987 American College of Rheumatology (ACR) criteria. UA>>UA=undifferentiated arthritis (UA) at baseline and at 2 years of follow-up; UA>>RA=classified as having UA at baseline and diagnosed as having RA at 2 year follow-up.
ACPA, anti-citrullinated protein antibody; CRP, C-reactive protein; DMARD, disease-modifying antirheumatic drug; ESR, erythrocyte sedimentation rate; IgM-RF, immunoglobulin M rheumatoid factor; MTX, methotrexate; SpA, spondyloarthritis; SJC66, 66-joint swollen joint count; TJC68, 68-joint tender joint count; TNF, tumour necrosis factor α; VAS, visual analogue scale of global disease activity.