Baseline patient characteristics
| Characteristic | nbDMARD (n=3673) | All TNF (n=11 881) | p Value* | Etanercept (n=4139) | Infliximab (n=3475) | Adalimumab (n=4267) | p Value† |
|---|---|---|---|---|---|---|---|
| Age, mean (SD) | 60 (12) | 56 (12) | <0.001 | 56 (12) | 56 (12) | 57 (12) | 0.018 |
| Sex (% female) | 2652 (72) | 9053 (76) | <0.001 | 3193 (77) | 2626 (76) | 3234 (76) | 0.203 |
| DAS28 (mean (SD)) | 5.1 (1.3) | 6.6 (1.0) | <0.001 | 6.6 (1.0) | 6.6 (1.0) | 6.5 (1.0) | <0.001 |
| HAQ score (mean (SD)) | 1.5 (0.8) | 2.0 (0.6) | <0.001 | 2.1 (0.6) | 2.1 (0.5) | 1.9 (0.6) | <0.001 |
| Disease duration (years (median (IQR))) | 6 (1, 15) | 11 (6–19) | <0.001 | 12 (6–19) | 12 (6–19) | 10(5–18) | <0.001 |
| Baseline steroid use (n (%)) | 845 (23) | 5228 (44) | <0.001 | 1979 (48) | 1609 (46) | 1664 (39) | <0.001 |
| Diabetes (n (%)) | 234 (6.7) | 675 (5.8) | 0.033 | 255 (6) | 169 (4) | 261 (6) | 0.026 |
| COPD (n (%)) | 304 (8) | 570 (5) | <0.001 | 222 (5) | 165 (5) | 183 (4) | 0.070 |
| Smoking (n (%)) | |||||||
| Current | 868 (24) | 2580 (22) | 0.001 | 846 (21) | 757 (22) | 977 (23) | 0.029 |
| Ex | 1454 (40) | 4510 (38) | 1576 (38) | 1314 (38) | 1620 (38) | ||
| Never | 1333 (36) | 4714 (40) | 1691 (41) | 1386 (40) | 1637 (39) | ||
| Prior large joint replacement (n (%))‡ | 521 (14) | 2837 (24) | <0.001 | 1090 (26) | 846 (24) | 901 (21) | <0.001 |
| Large joint replacement during follow-up (n (%))‡ | 481 (13) | 4390 (37) | <0.001 | 1907 (46) | 1111 (32) | 1372 (32) | <0.001 |
* Represents the significance of differences between the DMARD and anti-TNF cohorts using χ2 tests for categorical outcomes and Wilcoxon rank sum tests for continuous variables.
† Represents the significance of differences between the three anti-TNF drugs using χ2 tests for categorical outcomes and Kruskal–Wallis rank tests for continuous variables.
‡ Elbow, shoulder, hip, knee and ankle.
Anti-TNF, anti-tumour necrosis factor; COPD, chronic obstructive pulmonary disease; DAS28, 28-joint count disease activity score; HAQ, Health Assessment Questionnaire; nbDMARD, non-biological disease-modifying antirheumatic drug.