Country | Sweden | Denmark | Norway | |||||
Source cohort | EIRA* | SRQ* | SRQb* | DANBIO† | DRB† | NOR-DMARD† | ARCTIC* | NOR-VEAC* |
N patients | 2428 | 17 385 | 1930 | 12 493 | 1286 | 1783 | 230 | 404 |
Characteristics at treatment start | ||||||||
N women (%) | 1673 (69%) | 11 770 (68%) | 1336 (69%) | 8225 (66%) | 837 (65%) | 1225 (69%) | 141 (61%) | 269 (67%) |
Median age at baseline (IQR) | 57 (47–65) | 62 (51–71) | 60 (48–69) | 62 (51–71) | 58 (49–68) | 58 (48–66) | 54 (42–62) | 57 (45–66) |
Median calendar year of baseline (IQR) | 2008 (2004–2013) | 2012 (2007–2016) | 2015 (2011–2017) | 2016 (2013–2018) | 2014 (2013–2017) | 2006 (20032008) | 2011 (2011–2012) | 2013 (2011–2014) |
Median disease duration in years (IQR) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–0) | 0 (0–1) | 0 (0–1) | 0 (0–0) |
Seropositive disease‡ (%) | 1609 (68%) | 10 974 (65%) | 1184 (63%) | 7972 (66%) | 877 (71%) | 1221 (68%) | 186 (81%) | 287 (71%) |
Current smoker (%) | 512 (25%) | 2228 (16%) | 298 (16%) | 1266 (28%) | 149 (31%) | 525 (30%) | 55 (24%) | 89 (23%) |
Cotreatment with oral steroids (%) | 1188 (49%) | 9138 (53%) | 962 (50%) | 1482 (12%) | 174 (14%) | 1783 (100%) | 230 (100%) | 404 (100%) |
Visit-based clinical data | ||||||||
Treatment start | ||||||||
Median SJC(28) (IQR) | 8 (5–12) | 7 (4–11) | 6 (3–10) | 4 (1– 7) | 4 (1– 7) | 6 (3–10) | 6 (3–11) | 4 (1–8) |
Median TJC (IQR) | 7 (4–12) | 6 (3–10) | 6 (3–10) | 5 (2– 10) | 5 (2– 10) | 6 (3–12) | 6 (3–11) | 4 (1–8) |
Median CRP (IQR) | 13 (6–30) | 12 (5–31) | 11 (4–27) | 9 (3– 23) | 9 (3– 22) | 10 (5–27) | 7 (3–18) | 7 (3–20) |
Median ESR (IQR) | 28 (15–45) | 27 (14–46) | 26 (14–45) | NA | NA | 22 (12–40) | 20 (11–32) | 19 (11–36) |
Median Patient Global VAS (IQR) | 50 (30–70) | 52 (31–71) | 51 (32–71) | 58 (33– 79) | 60 (33– 80) | 47 (29–66) | 50 (31–70) | 45 (25–66) |
Median HAQ (IQR) | 1.00 (0.63–1.38) | 1.00 (0.50–1.38) | 1.00 (0.63–1.50) | 0.88 (0.38– 1.38) | 0.88 (0.38– 1.38) | 0.62 (0.25–1.00) | NA | 0.75 (0.38–1.25) |
Three months | ||||||||
Retention (%) | 2114 (99%) | 12 709 (98%) | 1526 (97%) | 9209 (98%) | 1019 (97%) | 1464 (94%) | 230 (100%) | 331 (96%) |
Persistence (%) | 2102 (98%) | 12 606 (97%) | 1495 (95%) | 8960 (95%) | 995 (95%) | 1464 (94%) | 223 (97%) | 331 (96%) |
EULAR good response | 910 (46%) | 5103 (47%) | 696 (53%) | 2815 (47%) | 269 (37%) | 447 (32%) | 126 (55%) | 59 (43%) |
Six months | ||||||||
Retention (%) | 1812 (93%) | 9401 (93%) | 1162 (92%) | 7373 (93%) | 848 (93%) | 1255 (83%) | 209 (100%) | 275 (90%) |
Persistence (%) | 1540 (79%) | 8177 (81%) | 976 (77%) | 6429 (82%) | 712 (78%) | 1255 (83%) | 176 (84%) | 275 (90%) |
EULAR good response | 850 (49%) | 3670 (43%) | 481 (45%) | 2051 (45%) | 205 (36%) | 449 (39%) | 141 (68%) | 52 (47%) |
12 months | ||||||||
Retention (%) | 1921 (89%) | 11 027 (89%) | 1402 (88%) | 8372 (89%) | 991 (87%) | 1129 (70%) | 182 (99%) | 262 (82%) |
Persistence (%) | 1470 (68%) | 8687 (70%) | 1037 (65%) | 6588 (70%) | 698 (61%) | 1129 (70%) | 133 (72%) | 261 (82%) |
EULAR good response | 889 (47%) | 4396 (43%) | 559 (41%) | 2446 (47%) | 276 (41%) | 498 (47%) | 142 (77%) | 51 (52%) |
Characteristics of Swedish, Danish and Norwegian treatment cohorts at the start of methotrexate (baseline) and outcomes during 1 year of follow-up. Percentages are calculated base on available data, for proportions of missing data, see online supplemental table S4.
*For EIRA, SRQ, SRQb, ARCTIC and NOR-VEAC data pertain specifically to patients diagnosed with RA within 12 months of symptom onset.
†For DANBIO, DRB and NORDMARD, information on RA symptom onset at diagnosis was not uniformly registered. For these cohorts, the data here presented refer to methotrexate treatment start within 6 months of RA diagnosis (irrespective of information on RA symptom duration at RA diagnosis).
‡Seropositivity defined as diagnosed with ICD code M05.8 or M05.9 and seronegative defined as diagnosed with M06.0 or M06.8 (and, if available, negative for anti-CCP and IgM RF).
ACR, American Congress of Rheumatology; ARCTIC, Aiming for Remission in rheumatoid arthritis: a randomised trial examining the benefit of ultrasound in a Clinical TIght Control regimen; CRP, C reactive protein; DANBIO, Danish Registry for Biologic Therapies in Rheumatology; DMARD, disease-modifying antirheumatic drug; DRB, Danish Rheumatologic Biobank; EIRA, Epidemiological Investigation of RA; ESR, erythrocyte sedimentation rate; EULAR, European Alliance of Associations for Rheumatology; ICD, International Classification of Diseases; NOR-DMARD, The Norwegian Antirheumatic Drug Register; NOR-VEAC, Norwegian Very Early Arthritic Clinic; RA, rheumatoid arthritis; SJC(28), swollen 28 joint count; SRQb, SRQ biobank; VAS, Visual Analogue Scale.