Table 1.
Cohort characteristics at baseline
| Characteristic | n/N (%), mean (SD) or median (IQR)* |
|---|---|
| Mean (SD) age at IP onset (years) | 55.4 (16.6) |
| Median (IQR) symptom duration (months) | 6.4 (3.6–12.0) |
| Gender: female, n/N (%) | 536/800 (67.0) |
| Smoking history | |
| Past smoker, n/N (%) | 301/797 (37.8) |
| Current smoker, n/N (%) | 164/797 (24.3) |
| Never smoker, n/N (%) | 465/797 (58.3) |
| Walking 5 m: any difficulty, n/N (%) | 178/637 (27.9) |
| Positive for rheumatoid factor, n/N (%) | 213/717 (29.7) |
| Positive for ACPA, n/N (%) | 228/708 (32.2) |
| Mean (SD) CRP concentration (mg/l) | 16.1 (27.0) |
| Mean (SD) HAQ score | 0.84 (0.74) |
| DMARD use, n (%) | 253/800 (31.6) |
| MTX use, n (%) | 136/800 (17.0) |
| Steroid use, n/N (%) | 134/800 (16.8) |
| NSAID use, n/N (%) | 505/800 (63.1) |
| Statin use, n/N (%) | 8/800 (1.0) |
| Cumulative ACR criteria for RA after 2 years: met criteria, n/N (%) | 387/800 (48.4) |
*
Denominator denotes number of patients for whom data were available.
ACPA, anticyclic citrullinated peptide antibody; ACR, American College of Rheumatology; CRP, C-reactive protein; DMARD, disease-modifying antirheumatic drug; HAQ, Health Assessment Questionnaire; IP, inflammatory polyarthritis; MTX, methotrexate; NSAID, non-steroidal anti-inflammatory drug; RA, rheumatoid arthritis.