Demographic, clinical, biological and drug characteristics of the study population at baseline and according to the occurrence of relapse during the spacing and discontinuation phases
| Parameter | Total (n=53) | Spacing phase | Discontinuation phase | ||||
| Non-relapser (n=34) | Relapser (n=19) | P value | Non-relapser (n=13) | Relapsers (n=38) | P value | ||
| Gender, female n (%) | 38 (72) | 20 (59) | 18 (95) | 0.009 | 7 (54) | 30 (79) | 0.14 |
| Age, median (IQR) | 58 (49–63) | 58 (50–63) | 56 (48,5–61) | 0.56 | 52 (47–62) | 58 (50–63) | 0.52 |
| Disease duration, median (IQR) | 11 (6–15) | 10 (6.3–12.8) | 12 (7–16) | 0.23 | 9 (8–11) | 12 (6.3–15) | 0.29 |
| bDMARD duration, median (IQR) | 5 (3–8) | 4 (3–7) | 7 (3.5–8) | 0.07 | 4 (3–7) | 5.5 (3–8) | 0.38 |
| DAS 28 ESR, median (IQR) | 1.8 (1.4–2.1) | 1.7 (1.4–2.1) | 2 (1.4–2.2) | 0.62 | 1.5 (1.3–1.9) | 2 (1.5–2.2) | 0.11 |
| DAS 28 CRP, median (IQR) | 1.6 (1.2–1.9) | 1.6 (1.2–1.9) | 1.6 (1.4–1.8) | 0.93 | 1.7 (1.5–1.9) | 1.6 (1.2–1.8) | 0.18 |
| SDAI, median (IQR) | 2 (1–3) | 1.6 (0.8–3) | 2 (1–3.1) | 0.28 | 2.4 (2–3) | 1 (1–2.9) | 0.13 |
| HAQ (0–3), median (IQR) | 0.1 (0–0.3) | 0.1 (0–0.3) | 0.1 (0–0.3) | 0.85 | 0.1 (0–0.3) | 0.1 (0–0.3) | 0.84 |
| RF positivity (>20 IU/mL), n (%) | 33 (62) | 19 (56) | 14 (74) | 0.25 | 8 (62) | 24 (63) | 1 |
| Anti-CCP positivity (>10 UA/mL), n (%) | 33 (62) | 24 (71) | 9 (47) | 0.14 | 9 (69) | 22 (58) | 0.52 |
| GS score, median (IQR) | 0 (0–2) | 0 (0–2) | 0 (0–0) | 0.39 | 0 (0–0) | 0 (0–2) | 0.37 |
| PD score, median (IQR) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0.59 | 0 (0–0) | 0 (0–0) | 0.5 |
| bDMARD | |||||||
| Certolizumab, n (%) | 1 (2) | 1 (3) | 0 (0) | 0.87 | 0 (0) | 0 (0) | 0.22 |
| Etanercept, n (%) | 24 (45) | 13 (38) | 11 (58) | 5 (38) | 18 (47) | ||
| Adalimumab, n (%) | 8 (15) | 6 (18) | 2 (11) | 1 (8) | 7 (18) | ||
| Abatacept, n (%) | 11 (21) | 8 (24) | 3 (16) | 2 (15) | 9 (24) | ||
| Infliximab, n (%) | 6 (11) | 4 (12) | 2 (11) | 3 (23) | 3 (8) | ||
| Tocilizumab, n (%) | 3 (6) | 2 (6) | 1 (5) | 2 (15) | 1 (3) | ||
| Methotrexate | |||||||
| N (%) | 42 (79) | 28 (82) | 14 (74) | 12 (92) | 28 (74) | 0.25 | |
| Dose, median (IQR) | 15 (7.5–15) | 15 (7.5–16.9) | 10 (8.8–15) | 0.47 | 15 (10–25) | 10 (5.6–15) | 0.24 |
| Prednisone | |||||||
| N (%) | 4 (8) | 2 (6) | 2 (11) | 0 (0) | 4 (11) | 0.56 | |
| Dose, median, IQR | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0.53 | 0 (0–0) | 0 (0–0) | 0.23 |
anti-CCP, anti-cyclic citrullinated peptide; bDMARD, biologic Disease-Modifying Anti-Rheumatic Drugs; CRP, C-reactive protein; DAS, Disease Activity Score; ESR, erythrocyte sedimentation rate; GS, grey scale; HAQ, Health Assessment Questionnaire; IQR, Interquartile range; PD, power Doppler; RF, rheumatoid factors; SDAI, Simplified Disease Activity Index.