Table 1.
Patient characteristics
| IMPROVED (N = 104) | RETRO (N = 57) | |
|---|---|---|
| Age, mean years (SD) | 49 (13) | 55 (13) |
| Female, n (%) | 67 (64%) | 37 (65%) |
| BMI, mean (SD) | 25 (4) | 25 (4) |
| Ever smoker, n (%) | 47 (46%) | 18 (32%) |
| Disease duration, median (IQR) | 19 (9–36) weeks^ | 5 (3–10) years |
| Anti-CCP2 IgG positive, n (%) | 85 (83%) | 34 (62%) |
| RF IgM positive, n (%) | 79 (79%) | 39 (68%) |
| Current DMARD use† | ||
| Methotrexate | 104 (100%) | 47 (82%) |
| Glucocorticoids | 0 (0%) | 11 (19%) |
| Other csDMARDS | 0 (0%) | 6‡ (11%) |
| Biological DMARDs | 0 (0%) | 21 (37%) |
| Etanercept | – | 5 (9%) |
| Adalimumab | – | 6 (11%) |
| Tocilizumab | – | 5 (9%) |
| Golimumab | – | 2 (4%) |
| Certolizumab | – | 3 (5%) |
| DAS44 at tapering/stopping moment, mean (SD) | 0.9 (0.4) | – |
| DAS28-ESR at tapering/stopping moment, mean (SD) | – | 1.8 (0.7) |
| Disease flare within 12 months | 78 (75%) | 26 (46%) |
| Calprotectin (ng/mL), median (IQR) | 1000 (230–2422) | 1000 (650–2000) |
SD standard deviation, IQR interquartile range, Anti-CCP2 anti-citrullinated protein 2 antibody, RF rheumatoid factor, cs/bDMARD conventional synthetic/biological disease-modifying antirheumatic drugs, DAS disease activity score, ESR erythrocyte sedimentation rate
^Disease duration is based on the moment of study inclusion; in the IMPROVED study, this excludes the first 4 months of treatment
†Categories are not mutually exclusive
‡Patients received sulfasalazine (n = 2), hydroxychloroquine (n = 2), leflunomide (n = 1), or azathioprine (n = 1)