Time-dependent predictors of ExRA. Cox regression analysis. Values are HR (95% CI).
| Variable | Bivariate Analysis | Analysis Adjusted for Age and Sex | Multivariate Multivariate Analysis* | Analysis*, Adjusted for Age and Sex | Analysis Adjusted for Age, Sex, and Propensity Score** | Multivariate Analysis*, Adjusted for Age, Sex, and Propensity Score** |
|---|---|---|---|---|---|---|
| All | ||||||
| Anti-TNF treatment, time dependent | 1.10 (0.75–1.61) | 1.21 (1.02–1.43) | 1.17 (0.75–1.83) | 1.38 (0.83–2.27) | 1.25 (1.04–1.49) | 1.63 (0.94–2.83) |
| HAQ, time dependent | 1.25 (0.81–1.94) | 1.45 (0.94–2.24) | 1.24 (0.78–1.99) | 1.29 (0.81–2.07) | ND | NA |
| RF-positive | ||||||
| Anti-TNF treatment, time dependent | 1.00 (0.65–1.55) | 1.24 (1.03–1.48) | 1.01 (0.60–1.70) | 1.39 (0.79–2.44) | 1.40 (1.19–1.66) | 1.63 (0.91–2.91) |
| HAQ, time dependent | 1.10 (0.65–1.86) | 1.31 (0.77–2.23) | 1.10 (0.62–1.92) | 1.18 (0.67–2.07) | ND | NA |
| RF-negative | ||||||
| Anti-TNF treatment, time dependent | 2.38 (0.89–6.35) | 1.10 (0.66–1.82) | 1.24 (0.31–4.95) | 1.08 (0.25–4.69) | 1.18 (0.70–1.98) | 1.33 (0.28–6.40) |
| HAQ, time dependent | 4.68 (1.84–11.86) | 4.58 (1.80–11.60) | 4.17 (1.28–13.60) | 4.39 (1.31–14.70) | ND | NA |
↵* Includes both time-dependent predictors.
↵** Propensity score for anti-TNF treatment based on age, sex, RA duration, first available HAQ, RF status, and treatment with methotrexate and glucocorticoids at baseline (RF status excluded in propensity scores for only RF-positive or -negative patients). RA: rheumatoid arthritis; ExRA: extraarticular RA; TNF: tumor necrosis factor; HAQ: Health Assessment Questionnaire; RF: rheumatoid factor; ND: not done; NA: not applicable.