Demographic, clinical, biochemical and imaging factors associated with flare
| Baseline characteristics | N (%) patients flared by 12 m | OR (95% CI) | p Value | |
|---|---|---|---|---|
| Age, per year | – | 1.00 (0.97 to 1.04) | 0.914 | |
| Sex | Male | 6/30 (20.0%) | 1.60 (0.56 to 4.57) | 0.380 |
| Female | 18/63 (28.6%) | |||
| Duration of RA | Per year | – | 1.01 (0.95 to 1.08) | 0.699 |
| Duration of remission | Per month | – | 1.00 (0.99 to 1.02) | 0.785 |
| Painful joints | Absent | 14/62 (22.6%) | 1.63 (0.63 to 4.26) | 0.317 |
| Present | 10/31 (32.3%) | |||
| Tender joints | Absent | 14/56 (25.0%) | 1.11 (0.43 to 2.86) | 0.827 |
| Present | 10/37 (27.0%) | |||
| Swollen joints | Absent | 10/42 (23.8%) | 1.21 (0.47 to 3.10) | 0.690 |
| Present | 14/51 (27.5%) | |||
| RF at baseline | Negative | 13/54 (24.1%) | 1.24 (0.49 to 3.16) | 0.654 |
| Positive | 11/39 (28.2%) | |||
| CCP at baseline | Negative | 6/26 (23.1%) | 1.36 (0.43 to 4.29) | 0.602 |
| Positive | 11/38 (28.9%) | |||
| CCP titre | Per unit | – | 0.999 (0.998 to 1.000) | 0.222 |
| Shared epitope | Absent | 12/36 (33.3%) | 0.50 (0.19 to 1.30) | 0.156 |
| Present | 11/55 (20.0%) | |||
| CRP | Normal | 17/72 (23.6%) | 1.74 (0.60 to 5.07) | 0.308 |
| Elevated | 7/20 (35.0%) | |||
| DAS28 remission | No | 12/41 (29.3%) | 0.73 (0.29 to 1.84) | 0.499 |
| Yes | 12/52 (23.1%) | |||
| SDAI remission | No | 17/62 (27.4%) | 0.77 (0.28 to 2.12) | 0.616 |
| Yes | 7/31 (22.6%) | |||
| 1981 ACR remission | No | 14/43 (32.6%) | 0.52 (0.20 to 1.33) | 0.171 |
| Yes | 10/50 (20.0%) | |||
| 2011 ACR/EULAR remission | No | 20/80 (25.0%) | 1.33 (0.37 to 4.81) | 0.660 |
| Yes | 4/13 (30.8%) | |||
| HAQ-DI, (0.0–0.3) | Per 0.1 unit | – | 1.27 (1.07 to 1.52) | 0.006 |
| RAQoL, (0–30) | Per unit | – | 1.10 (1.01 to 1.20) | 0.036 |
| XR erosions* | Absent | 5/15 (33.3%) | 0.69 (0.21 to 2.30) | 0.548 |
| Present | 18/70 (25.7%) | |||
| US GS (score>0) | Absent | 2/10 (20.0%) | 1.44 (0.28 to 7.32) | 0.658 |
| Present | 22/83 (26.5%) | |||
| Number of joints with US GS (score>0) per patient | Per joint | – | 1.04 (0.84 to 1.29) | 0.733 |
| Number of joints with US GS (score>0) per patient | Per joint | – | 1.04 (0.84 to 1.29) | 0.733 |
| US PD (score>0) | Absent | 4/35 (11.4%) | 4.08 (1.26 to 13.19) | 0.014 |
| Present | 20/58 (34.5%) | |||
| Number of joints with US PD (score>0) per patient | Per joint | – | 1.43 (1.01 to 2.02) | 0.044 |
↵* Only 85 patients were included in the XR analysis due to missing data.
ACR, American College of Rheumatology; CCP, cyclic citrullinated protein; CRP, C reactive protein; DAS28, 28-joint count Disease Activity Score; EULAR, European League Against Rheumatism; HAQ-DI, Health Assessment Questionnaire Disability Index; RA, rheumatoid arthritis; RAQoL, RA Quality of Life Questionnaire score; RF, rheumatoid factor; SDAI, Simplified Disease Activity Index; US GS, ultrasound Grey Scale; US PD, ultrasound power Doppler; XR, x-ray.