Baseline characteristics of all 13 502 patients in the BSRBR-RA starting a first-line TNFi between 2001 and 2014
| All patients | bDMARD refractory | Remaining patients | |
| N | 13 502 | 867 | 12 635 |
| First TNFi (n=13 502) | |||
| Etanercept | 4612 (34%) | 285 (33%) | 4327 (34%) |
| Infliximab | 3794 (28%) | 246 (28%) | 3548 (28%) |
| Adalimumab | 4322 (32%) | 391 (34%) | 4031 (32%) |
| Certolizumab | 774 (6%) | 45 (5%) | 729 (6%) |
| Registration year (category) (n=13 502) | – | – | – |
| 2001–2008 | 11 654 (86%) | 778 (90%) | 10 876 (86%) |
| 2011–2014 | 1848 (14%) | 89 (10%) | 1759 (14%) |
| Women (n=13 502) | 10 269 (76%) | 705 (81%) | 9564 (76%) |
| Age (years) (n=13 502) | 57 (49 to 65) | 52 (44 to 59) | 58 (49 to 66) |
| Age (category) (n=13 502) | – | – | – |
| 16–50 | 3888 (29%) | 381 (44%) | 3507 (28%) |
| 51–90 | 9614 (71%) | 486 (56%) | 9128 (72%) |
| Disease duration (years) (n=13 360) | 10 (5 to 18) | 9 (4 to 16) | 10 (5 to 18) |
| Disease duration (category) (n=13 360) | – | – | – |
| 0–10 | 6835 (51%) | 494 (57%) | 6341 (51%) |
| 11–72 | 6514 (49%) | 368 (43%) | 6157 (49%) |
| Concurrent methotrexate (n=13 502) | 8537 (63%) | 578 (67%) | 7959 (63%) |
| Concurrent steroids (n=13 502) | 5620 (42%) | 364 (42%) | 5256 (42%) |
| Total comorbidities† (n=13 502) | – | – | – |
| None | 6327 (47%) | 408 (47%) | 5919 (47%) |
| 1 comorbidity | 4589 (34%) | 294 (34%) | 4295 (34%) |
| 2 comorbidities | 1894 (14%) | 122 (14%) | 1772 (14%) |
| 3+ comorbidities | 692 (5%) | 43 (5%) | 649 (5%) |
| Smoking status (n=13 351) | – | – | – |
| Current smoker | 2899 (22%) | 248 (29%) | 2651 (21%) |
| Ex-smoker | 5068 (38%) | 284 (33%) | 4784 (38%) |
| Never smoked | 5384 (40%) | 330 (38%) | 5054 (40%) |
| Body mass index (kg/m2) (n=11 499*) | 26 (23 to 30) | 26 (23 to 31) | 26 (23 to 30) |
| Obese (body mass index ≥30) (n=11 499*) | 2951 (26%) | 224 (30%) | 2727 (25%) |
| Disease activity | – | – | – |
| Tender joint count (range 0–28) (n=13 091) | 15 (10 to 22) | 16 (11 to 23) | 15 (10 to 21) |
| Swollen joint count (range 0–28) (n=13 083) | 10 (6 to 15) | 11 (7 to 16) | 10 (6 to 15) |
| Patient global assessment (range 0–10 cm) (n=13 000) | 7.5 (6.2 to 8.7) | 7.8 (6.6 to 9.0) | 7.5 (6.1 to 8.6) |
| ESR (mm/s) (n=12 084*) | 38 (22 to 62) | 36 (22 to 60) | 38 (22 to 62) |
| CRP (mm/s) (n=5274*) | 27 (12 to 57) | 28 (11 to 56) | 27 (12 to 57) |
| DAS28 (range 0–10) (n=13 255) | 6.5 (5.8 to 7.2) | 6.6 (5.9 to 7.3) | 6.5 (5.8 to 7.2) |
| HAQ (range 0–3) (n=12 364*) | 2.0 (1.6 to 2.4) | 2.1 (1.8 to 2.5) | 2.0 (1.6 to 2.4) |
| SF-36: Physical Component Score‡ (n=8702*) | 15 (10 to 21) | 14 (10 to 19) | 15 (10 to 21) |
| SF-36: Mental Component Score‡ (n=8702*) | 42 (34 to 51) | 40 (32 to 50) | 42 (34 to 51) |
| Index of multiple deprivation (excluding Northern Ireland) (n=12 711*) | – | – | – |
| Lowest quintile (most deprived) | 2082 (16%) | 165 (20%) | 1917 (16%) |
| Middle 3 quintiles | 8008 (63%) | 494 (61%) | 7514 (63%) |
| Highest quintile (least deprived) | 2621 (21%) | 147 (18%) | 2474 (21%) |
Results presented as N (%) or median (IQR).
*More than 5% missing data.
†Total comorbidities—hypertension, ischaemic heart disease, stroke, lung disease, renal disease, diabetes, depression, liver disease. ‡SF-36; greater score indicates better health.
bDMARD, biologic disease-modifying antirheumatic drug; BSRBR-RA, British Society for Rheumatology Biologics Register for rheumatoid arthritis; CRP, C reactive protein; DAS28, 28-joint Disease Activity Score; ESR, erythrocyte sedimentation rate; HAQ, Health Assessment Questionnaire; SF-36, 36-item Short Form Survey for quality of life; TNFi, tumour necrosis factor-alpha inhibitor.