Table 1.
Baseline characteristics of rheumatoid arthritis patients
| Baseline characteristics | RA patients (n = 457) |
|---|---|
| Female, n (%) | 378 (82.7) |
| Age, years, mean ± SD | 49.5 ± 13.1 |
| Disease duration, month, median (IQR) | 54 (24–118) |
| BMI, kg/m2, mean ± SD | 21.8 ± 3.4 |
| Smoking habits | |
| Active smoking, n (%) | 68 (14.9) |
| Exposure to second hand smoke, n (%) | 139 (30.4) |
| Without exposure to smoke, n (%) | 250 (54.7) |
| Positive RF, n (%) | 300 (65.6) |
| Positive ACPA, n (%) | 317 (69.4) |
| Core disease activity indicators | |
| 28TJC, median (IQR) | 2 (0–5) |
| 28SJC, median (IQR) | 1 (0–4) |
| ESR, (mm/h), median (IQR) | 27 (15–47) |
| CRP, (mg/L), median (IQR) | 4.6 (3.3–14.5) |
| DAS28‐CRP, median (IQR) | 3.2 (2.0–4.3) |
| SDAI, median (IQR) | 11.0 (4.3–21.3) |
| CDAI, median (IQR) | 10 (4–19) |
| Functional indicators | |
| HAQ‐DI, median (IQR) | 0.25 (0–0.75) |
| Functional limitation, n (%) | 70 (15.3) |
| Radiographic assessment | |
| mTSS, median (IQR) | 13.0 (4.5–38.3) |
| Bony erosion, n (%) | 426 (93.2) |
| RJD, n (%) | 263 (57.5) |
| Previous medications | |
| Treatment naïve, n (%) | 77 (16.8) |
| Glucocorticosteroids, n (%) | 243 (53.2) |
| Methotrexate, n (%) | 299 (65.4) |
| Leflunomide, n (%) | 236 (51.6) |
| Biologic agents, n (%) | 30 (6.6) |
Functional limitation, HAQ‐DI > 1; Bony erosion, JE subscore > 0; RJD, radiographic joint damage (mTSS > 10); treatment naïve, without previous glucocorticosteroids or DMARDs therapy for 6 months before enrolment; IQR, interquartile range; SD, standard deviation.