Predictors of discontinuation of first biologic
| Baseline predictors | Time-varying predictors | |||||
|---|---|---|---|---|---|---|
| Univariable | Multivariable Research Model N=2279 | Multivariable Clinical Model N=2279 | Univariable | Multivariable Research Model N=2263 | Multivariable Clinical Model N=2262 | |
| Age (years) | 1.01 (1.00 to 1.01) | 1.01 (1.00 to 1.01) | 1.01 (1.00 to 1.01) | 1.01 (1.00 to 1.01) | 1.01 (1.00 (1.01) | 1.01 (1.00 to 1.01) |
| Patient global severity (0–10) | 1.07 (1.04 to 1.09) | * | 1.05 (1.03 to 1.08) | 1.07 (1.04 to 1.09) | * | * |
| Comorbidity index (0–9) | 1.14 (1.09 to 1.19) | 1.09 (1.04 to 1.13) | 1.11 (1.06 to 1.15) | 1.14 (1.10 to 1.18) | 1.06 (1.01 to 1.10) | 1.07 (1.03 to 1.11) |
| Smoking | 1.17 (0.98 to 1.40) | 1.22 (1.02 to 1.46) | 1.23 (1.03 to 1.47) | 1.17 (0.98 to 1.40) | * | * |
| MTX | 0.84 (0.74 to 0.95) | 0.84 (0.74 to 0.95) | 0.84 (0.74 to 0.95) | † | † | † |
| SF-36 MCS (0–100) | 0.99 (0.98 to 0.99) | 0.99 (0.98 to 0.99) | ‡ | 0.99 (0.98 to 0.99) | * | ‡ |
| SF-36 PCS (0–100) | 0.99 (0.98 to 0.99) | * | ‡ | 0.97 (0.97 to 0.98) | 0.99 (0.98 to 0.99) | ‡ |
| RADAI (0–10) | 1.09 (1.04 to 1.13) | * | * | 1.24 (1.19 to 1.29) | 1.23 (1.16 to 1.30) | 1.28 (1.22 to 1.35) |
| Fibromyalginess (0–31) | 1.03 (1.02 to 1.04) | 1.02 (1.01 to 1.03) | ‡ | 1.04 (1.03 to 1.05) | * | ‡ |
| Pain scale (0–10) | 1.04 (1.02 to 1.07) | * | * | 1.04 (1.02 to 1.07) | 0.95 (0.92 to 0.98) | 0.96 (0.93 to 0.98) |
All analyses were adjusted for biologic drug class (anti-TNF vs other) and analyses of whole study period were adjusted for onset of biologic therapy ≥2005.
Other variables that were tested in the univariable analysis and eventually included in the multivariable analysis, but that were not part of any final model: comedication with leflunomide, comedication with prednisone, employed status, HAQ, fatigue scale, sleep scale, educational level, comedication with DMARDs, comedication with NSAIDs, disease duration, number of DMARDs previously made, gender, marital status, body mass index, ethnicity, insurance type, income, biological drug.
*Not selected during multivariable regression analysis (p≥0.05).
†Not included in the multivariable model (p value in the univariable model ≥0.20).
‡Not included in this short ‘clinical’ model (to present a model with variables more used in clinical practice).
DMARDs, disease-modifying antirheumatic drugs; HAQ, Health Assessment Questionnaire; MTX, methotrexate; NSAIDs, non-steroidal anti-inflammatory drugs; RADAI, rheumatoid arthritis disease activity index; SF-36 MCS and PCS, Short Form 36 mental component summary and physical component summary; TNF, tumour-necrosis factor.