Table 1.
Baseline characteristics for the overall cohort and first-line biologic users
| Overall cohort (n = 247) |
First-line users (n = 192) |
|||||
|---|---|---|---|---|---|---|
| Baseline characteristics | TCZ (n = 47) | TNFi (n = 200) | TCZ (n = 18) | TNFi (n = 174) | ||
| Continuous variables, mean (s.d.) | P, t-test | P, t-test | ||||
| Follow-up duration, months | 9.6 (7.4) | 16.8 (15.6) | <0.001* | 9.4 (6.6) | 16.6 (16) | 0.001* |
| Age, year | 60.3 (11.4) | 57.7 (14.3) | 0.179 | 60.6 (8.9) | 58.1 (14) | 0.303 |
| BMIa | 23.9 (4.2) | 22.9 (3.8) | 0.133 | 22.6 (4.0) | 22.8 (3.7) | 0.889 |
| RA disease duration, year | 8.8 (7.3) | 8.1 (9.2) | 0.640 | 9.1 (8.6) | 7.9 (9.4) | 0.616 |
| Prednisolone dose, mg | 7.3 (4.3) | 7.0 (4.4) | 0.684 | 7.0 (5.7) | 6.8 (4.5) | 0.876 |
| MTX dose, mg/week | 6.9 (4.7) | 7.0 (3.8) | 0.894 | 4.3 (4.0) | 6.9 (3.6) | 0.015* |
| DAS-28-ESR (three variables) | 4.8 (1.1) | 4.9 (1.2) | 0.552 | 4.9 (1.2) | 5.0 (1.2) | 0.781 |
| DAS-28-ESR (four variables)b | 5.0 (1.2) | 5.1 (1.3) | 0.503 | 5.0 (1.3) | 5.2 (1.3) | 0.660 |
| Categorical variables, % | P, Fisher's exact test | P, Fisher's exact test | ||||
| Male | 19.1 | 25.0 | 0.452 | 22.2 | 25.9 | 1.000 |
| Elderly (age >65 year) | 36.2 | 34.5 | 0.866 | 38.9 | 33.9 | 0.795 |
| Current smokerc | 17.4 | 16.7 | 1.000 | 11.1 | 16.7 | 1.000 |
| RF/ACPA positivity | 89.4 | 89.0 | 1.000 | 94.4 | 88.5 | 0.699 |
| Chronic kidney disease | 12.8 | 7.5 | 0.250 | 11.1 | 7.5 | 0.637 |
| Lung disease | 25.5 | 27.0 | 1.000 | 27.8 | 25.9 | 0.786 |
| Heart disease | 4.3 | 3.5 | 0.682 | 0.0 | 3.4 | 1.000 |
| Diabetes mellitus | 21.3 | 19.5 | 0.839 | 11.1 | 19.5 | 0.534 |
| Isoniazid prophylaxis | 63.8 | 69.0 | 0.492 | 61.1 | 70.7 | 0.424 |
| Concomitant autoimmune disease | 21.3 | 15.5 | 0.383 | 27.8 | 14.9 | 0.178 |
| FM | 6.4 | 6.5 | 1.000 | 0.0 | 6.3 | 0.604 |
| Prior history of malignancy | 10.6 | 3.5 | 0.056 | 22.2 | 3.4 | 0.008* |
| Prednisolone use | 91.5 | 91.0 | 1.000 | 83.3 | 89.7 | 0.424 |
| MTX use | 74.5 | 85.0 | 0.089 | 55.6 | 85.6 | 0.004* |
| NSAIDs use | 44.7 | 56.0 | 0.194 | 61.1 | 56.9 | 0.806 |
aNot available in eight patients. bNot available in 42 patients. cNot available in 21 patients. *Statistically significant. TCZ: tocilizumab; TNFi: TNF inhibitors.