Baseline disease characteristics and medication use by therapy type and by route of MTX administration.
| Characteristics | Monotherapy, n = 153 | Combination Therapy, n = 661 | Total, n = 814 | p | Oral MTX, n = 285 | SC MTX, n = 230 | Total, n = 515 | p |
|---|---|---|---|---|---|---|---|---|
| Disease characteristics | ||||||||
| Disease duration, yrs, mean (SD) | 12.3 (10.0) | 8.8 (9.9) | 9.4 (10.0) | < 0.0001* | 8.7 (9.9) | 7.9 (9.5) | 8.3 (9.8) | 0.32 |
| Early RA‡, n (%) | 16 (10.5) | 134 (20.3) | 150 (18.4) | 0.004* | 63 (22.1) | 50 (21.7) | 113 (21.9) | 0.92 |
| Ever presence of erosion, n (%) | ||||||||
| Yes | 79 (51.6) | 314 (47.5) | 393 (48.3) | 0.002* | 128 (44.9) | 115 (50.0) | 243 (47.2) | 0.17 |
| Unsure | 23 (15.1) | 63 (9.5) | 86 (10.6) | 33 (11.6) | 16 (7.0) | 49 (9.5) | ||
| Missing | 12 (10.3) | 41 (6.5) | 53 (7.0) | 26 (9.1) | 20 (8.7) | 46 (8.9) | ||
| RF-positive, n (%) | ||||||||
| Yes | 106 (69.3) | 456 (69.0) | 562 (69.0) | 0.20 | 202 (70.9) | 159 (69.1) | 361 (70.1) | 0.17 |
| Missing | 19 (12.4) | 43 (6.5) | 62 (7.7) | 24 (8.4) | 9 (3.9) | 33 (6.4) | ||
| Swollen joint count (0–28), mean (SD)§ | 8.2 (5.8) | 7.0 (5.0) | 7.2 (5.2) | 0.02* | 6.8 (5.1) | 6.6 (4.4) | 6.7 (4.8) | 0.61 |
| Tender joint count (0–28), mean (SD)¶ | 7.5 (6.3) | 7.6 (7.0) | 7.6 (6.6) | 0.90 | 7.8 (6.7) | 6.9 (5.8) | 7.4 (6.3) | 0.12 |
| DAS28-ESR, mean (SD)†† | 4.8 (1.4) | 4.7 (1.4) | 4.7 (1.4) | 0.64 | 4.7 (1.4) | 4.6 (1.4) | 4.7 (1.4) | 0.45 |
| PGA (1–10), mean (SD)‡‡ | 4.9 (2.5) | 4.8 (2.4) | 4.8 (2.4) | 0.71 | 4.8 (2.5) | 4.8 (2.4) | 4.8 (2.4) | 0.91 |
| PtGA (1–10), mean (SD)§§ | 5.8 (2.8) | 5.5 (2.6) | 5.6 (2.7) | 0.32 | 5.5 (2.6) | 5.4 (2.7) | 5.4 (2.6) | 0.69 |
| HAQ-DI (0–3), mean (SD)¶¶ | 1.5 (0.7) | 1.3 (0.7) | 1.4 (0.8) | 0.05* | 1.3 (0.7) | 1.3 (0.7) | 1.3 (0.7) | 0.81 |
| No. comorbidities, mean (SD)††† | 3.3 (2.1) | 2.7 (2.0) | 2.8 (2.0) | 0.001* | 2.7 (1.9) | 2.6 (2.0) | 2.6 (1.9) | 0.49 |
| Medication use | ||||||||
| Prior use of csDMARD, n (%) | 147 (96.1) | 601 (90.9) | 748 (91.9) | 0.43 | 264 (92.6) | 204 (88.7) | 468 (90.9) | 0.12 |
| Prior use of bDMARD, n (%) | 75 (49.0) | 193 (29.2) | 268 (32.9) | < 0.0001* | 87 (30.5) | 57 (24.8) | 144 (27.9) | 0.14 |
| Type of bDMARD, n (%) | ||||||||
| Non-TNFi | 36 (23.5) | 102 (15.4) | 138 (17.0) | 0.02* | 37 (13.0) | 36 (15.7) | 73 (14.2) | 0.39 |
| TNFi | 117 (76.5) | 559 (84.6) | 676 (83.0) | 248 (87.0) | 194 (84.3) | 442 (85.8) | ||
| Use of MTX at start of bDMARD, n (%) | NA | 515 (78.0) | 515 (66.3) | NA | 285 (100) | 230 (100) | 515 (100) | NA |
| Additional use of csDMARD in MTX users, n (%) | ||||||||
| At least 1 csDMARD other than MTX | NA | 258 (50.1)‡‡‡ | 258 (50.1)‡‡‡ | NA | 144 (50.5) | 114 (49.6) | 258 (50.1) | 0.14 |
| Hydroxychloroquine | NA | 163 (31.7)‡‡‡ | 163 (31.7)‡‡‡ | NA | 87 (30.5) | 76 (33.0) | 163 (31.7) | 0.54 |
| Leflunomide | NA | 108 (21.0)‡‡‡ | 108 (21.0)‡‡‡ | NA | 62 (21.8) | 46 (20.0) | 108 (21.0) | 0.63 |
| Sulfasalazine | NA | 72 (14.0)‡‡‡ | 72 (14.0)‡‡‡ | NA | 34 (11.9) | 38 (16.5) | 72 (14.0) | 0.14 |
| Other | NA | 8 (1.6)‡‡‡ | 8 (1.6)‡‡‡ | NA | 4 (1.4) | 4 (1.7) | 8 (1.6) | 0.76 |
| MTX administration route, n (%)‡‡‡ | ||||||||
| Oral | NA | 285 (55.3) | 285 (55.3) | NA | 285 (100) | 0 (0.0) | 285 (55.3) | NA |
| SC | NA | 230 (44.7) | 230 (44.7) | 0 (0.0) | 230 (100) | 230 (44.7) | NA | |
| MTX dose, mg/week, mean (SD) | 18.8 (6.0) | 20.7 (5.6) | 19.7 (5.9) | 0.0003* | ||||
| MTX dose category, mg/week, n = 498 | ||||||||
| ≤ 15 | 81 (28.4) | 47 (20.4) | 128 (24.9) | < 0.0001* | ||||
| 15–20 | 148 (51.9) | 71 (30.9) | 219 (42.5) | |||||
| > 20 | 56 (19.7) | 112 (48.7) | 168 (32.6) | |||||
↵* Statistically significant p value.
↵‡ Disease duration ≤ 1 year.
↵§ Available n = 682 (435 for MTX users).
↵¶ Available n = 671 (429 for MTX users).
↵†† Available n = 586 (374 for MTX users).
↵‡‡ Available n = 618 (398 for MTX users).
↵§§ Available n = 615 (397 for MTX users).
↵¶¶ Available n = 583 (367 for MTX users).
↵††† Available n = 765 (483 for MTX users).
↵‡‡‡ Proportions based on the no. MTX users (n = 515). DAS28-ESR: 28-joint count Disease Activity Score using erythrocyte sedimentation rate; csDMARD: conventional synthetic disease-modifying antirheumatic drugs; bDMARD: biologic DMARD; HAQ-DI: Health Assessment Questionnaire–Disability Index; MTX: methotrexate; NA: not available; PGA: physician’s global assessment; PtGA: patient’s global assessment; RA: rheumatoid arthritis; RF: rheumatoid factor; SC: subcutaneous; TNFi: tumor necrosis factor inhibitor.