Patient demographic and disease characteristics, treatments and beliefs about medications
| Characteristic | RA population (n=1943) | PsA population (n=635) | AS population (n=812) | P Values |
| Sociodemographic parameters | ||||
| Female, n (%) | 1597 (82.2) | 294 (46.3) | 232 (28.6) | <0.0001 |
| White, n (%)* | 1351 (70.0) | 571 (90.1) | 557 (68.8) | <0.0001 |
| Western Europe and Canada | 892 (95.5) | 443 (98.9) | 399 (94.3) | |
| Eastern Europe and Middle East | 360 (83.5) | 96 (96.0) | 140 (98.6) | |
| Latin America | 31 (8.4) | 7 (14.0) | 1 (2.4) | |
| Asia Pacific | 68 (32.2) | 25 (67.6) | 17 (8.3) | |
| Age, mean±SD (median), years† | 54.8±13.5 (56.0) | 50.7±12.4 (51.0) | 42.5±12.4 (42.0) | <0.001 |
| Duration of formal education, mean±SD (median), years‡ | 11.5±4.6 (12.0) | 12.3±4.1 (12.0) | 13.0±3.9 (13.0) | <0.001 |
| Duration of symptoms before diagnosis, years§ | <0.0001 | |||
| <1 | 1042 (53.9) | 257 (40.5) | 216 (26.6) | |
| 1–3 | 530 (27.4) | 187 (29.5) | 181 (22.3) | |
| >3 | 362 (18.7) | 190 (30.0) | 414 (51.0) | |
| Duration of disease, mean±SD (median), years† | 9.2±8.8 (6.3) | 9.9±9.5 (7.0) | 9.3±8.9 (6.1) | 0.248 (RA vs PsA) 0.881 (RA vs AS) 0.379 (PsA vs AS) |
| Current disease activity, n (%)¶,** | 0.0194 | |||
| Mild or mild to moderate disease | 1371 (70.7) | 480 (75.6) | 604 (74.5) | |
| ≥Moderate disease | 569 (29.3) | 155 (24.4) | 207 (25.5) | |
| Prior disease activity, n (%)**,†† | 0.277 | |||
| Mild or mild to moderate disease | 318 (16.5) | 91 (14.3) | 117 (14.6) | |
| ≥Moderate disease | 1611 (83.5) | 544 (85.7) | 686 (85.4) | |
| >3 prior treatments, n (%) | 389 (20.0) | 92 (14.5) | 125 (15.4) | 0.0007 |
| Prior TNFi therapy, n (%) | 598 (30.8) | 253 (39.8) | 411 (50.6) | <0.0001 |
| Response to current treatment, n (%)**,‡‡ | <0.001 | |||
| Complete response | 921 (47.5) | 335 (52.8) | 463 (57.4) | |
| Partial response | 941 (48.5) | 270 (42.6) | 310 (38.2) | |
| No response | 57 (2.9) | 13 (2.1) | 25 (3.1) | |
| Duration of current treatment, mean±SD (median), years | 5.3±5.3 (3.6) | 4.1±4.5 (2.9) | 3.8±4.3 (2.6) | <0.001 (RA vs PsA and AS) 0.263 (PsA vs AS) |
| Patients currently taking IMID-related drugs by category, n (%) | NA | |||
| csDMARD-TNFi combination | 640 (32.9) | 200 (31.5) | 151 (18.6) | |
| NSAID-TNFi combination | NA | NA | 123 (15.1) | |
| TNFi monotherapy | 175 (9.0) | 216 (34.0) | 374 (46.1) | |
| NSAID-csDMARD combination | NA | NA | 60 (7.4) | |
| csDMARD monotherapy | 1128 (58.1) | 219 (34.5) | 25 (3.1) | |
| NSAID monotherapy | NA | NA | 79 (9.7) | |
| Patients currently taking IMID-related drugs, n (%) | NA | |||
| TNFi | 815 (41.9) | 416 (65.5) | 648 (79.8) | |
| Methotrexate | 1399 (72.0) | 343 (54.0) | 116 (14.3) | |
| NSAID | NA | NA | 310 (38.2) | |
| GC | 658 (33.9) | 51 (8.0) | 51 (6.3) | |
| Hydroxychloroquine | 348 (17.9) | 9 (1.4) | 1 (0.1) | |
| Leflunomide | 288 (14.8) | 50 (7.9) | 6 (0.7) | |
| Aminosalicylate§§ | 149 (7.7) | 44 (6.9) | 123 (15.1) | |
| ≥1 other drug¶¶ | 27 (1.4) | 12 (1.9) | 5 (0.6) | |
| BIPQ item score; 0–10 for each component, mean±SD (median)*** | ||||
| 1—Consequences | 5.3±2.9 (5.0) | 5.3±2.8 (5.0) | 5.5±2.8 (5.0) | 0.870 (RA vs PsA) 0.275 (RA vs AS) 0.459 (PsA vs AS) |
| 2—Timeline | 8.7±2.3 (10.0) | 8.9±2.1 (10.0) | 8.5±2.3 (10.0) | 0.100 (RA vs PsA) 0.003 (RA vs AS) <0.001 (PsA vs AS) |
| 8—Emotional Representation | 5.3±3.1 (5.0) | 5.4±3.1 (6.0) | 5.2±3.0 (5.0) | 0.301 (RA vs PsA) 0.608 (RA vs AS) 0.194 (PsA vs AS) |
| BMQ-Specific score; 5–25 for each component, mean±SD (median) | ||||
| Necessity | 19.8±3.4 (20.0) | 19.6±3.5 (20.0) | 18.9±3.8 (20.0) | 0.112 (RA vs PsA) <0.001 (RA vs AS) 0.001 (PsA vs AS) |
| Concerns | 14.7±3.9 (15.0) | 14.0±3.9 (14.0) | 14.2±3.9 (14.0) | <0.001 (RA vs PsA and AS) 0.261 (PsA vs AS) |
| BMQ-General Harm score; 4–20, mean±SD (median)††† | 10.0±3.0 (10.0) | 9.9±3.0 (10.0) | 9.5±2.7 (9.0) | 0.301 (RA vs PsA) <0.001 (RA vs AS) 0.016 (PsA vs AS) |
Treatments: csDMARD monotherapy=csDMARDs±GCs; csDMARD-TNFi combination=TNFi +csDMARDs±NSAIDs±GCs; NSAID monotherapy=NSAIDs±GCs; NSAID-csDMARD combination=csDMARDs +NSAIDs±GCs; NSAID-TNFi combination=TNFi +NSAIDs±GCs;TNFi monotherapy=TNFi±GCs.
P values were from a Wilcoxon (continuous variables) or Pearson chi-square (categorical variables) test.
*Data missing for 16 patients (RA, n=13; PsA, n=1; AS, n=2).
†Data missing for 7 patients (RA, n=6; PsA, n=1).
‡Data missing for 117 patients (RA, n=64; PsA, n=22; AS, n=31).
§Data missing for 11 patients (RA, n=9; PsA, n=1; AS, n=1).
¶Data missing for 4 patients (RA, n=3; AS, n=1).
**Assessed by treating physician; prior and current disease activity was evaluated using a 5-point rating scale (ie, mild, mild to moderate, moderate, moderate to severe, severe), and treatment response was categorised as ‘complete response’, ‘partial response’, ‘no response’ or ‘not evaluable’.
††Data missing for 23 patients (RA, n=14; AS, n=9).
‡‡Data missing for 10 patients (RA, n=3; PsA, n=1; AS, n=6) and not evaluable for 45 patients (1.3%; RA, n=21 (1.1%); PsA, n=16 (2.5%); AS, n=8 (1.0%)).
§§Includes sulfasalazine and mesalazine.
¶¶Includes gold compounds, azathioprine/6-mercaptopurine, cyclosporine and tacrolimus.
***Data missing for 75 patients (RA, n=42; PsA, n=16; AS, n=17).
†††Data missing for 35 patients (RA, n=22; PsA, n=8; AS, n=4).
AS, ankylosing spondylitis; BIPQ, Brief Illness Perception Questionnaire; GC, glucocorticoid; IMID, immune-mediated inflammatory disease; MMAS-4©, 4-item Morisky Medication Adherence Scale; NA, not applicable; NSAID, non-steroidal anti-inflammatory drug; PsA, psoriatic arthritis; RA, rheumatoid arthritis; TNFi, tumour necrosis factor inhibitor; csDMARD, conventional synthetic disease-modifying antirheumatic drug.