Background Methotrexate (MTX) is the most widely prescribed DMARD and at present the first line treatment for rheumatoid arthritis (RA). Knowledge about predictors of response to MTX is of potential clinical use as it is important to know which patients who are less likely to respond, so that these patients could receive more potent treatment earlier.
Objectives To identify clinical predictors of EULAR good response to MTX treatment.
Methods Data was extracted from the NOR-DMARD register where adult patients with inflammatory arthropathies starting a new DMARD treatment have been consecutively included since 2000 and followed longitudinally. For this analysis RA patients satisfying the following criteria were included: disease duration <1 year, no prior DMARD and DAS28 ≥3.2 (moderate or high disease activity) at baseline were included [N=588, 67% females, mean (SD) age 56.3 (13.5) years, 62% rheumatoid factor (RF) positive, DAS28 5.29 (1.15), MHAQ score 0.74 (0.51)]. The following covariates were tested in univariate logistic regression with 3-month EULAR good response as the dependent variable: gender, age, disease duration (>1 month vs. ≤1 month), cigarette smoking habits, level of education, RF status, swollen and tender joint counts (28 joints), physician and patient global assessments, fatigue, ESR, MHAQ score, and concurrent prednisolone and NSAID use. CRP and pain VAS were excluded due to co-linearity with ESR and patient global, respectively. Variables yielding a p-value <0.25 were included in a subsequent multivariate regression analysis, and non-significant variables were removed from the model one at the time (starting with the least significant variable), checking for confounding. Appropriate tests for linearity and goodness of fit were performed.
Results EULAR good response was achieved by 33.2% of patients at 3 months. Disease duration, baseline prednisolone use and lower baseline ESR and fatigue came out as independent predictors, and university/college education was significant vs. the lowest level of education (Table). The fit of the model was satisfactory (Hosmer-Lemeshow goodness of fit test: p=0.53).
Conclusions Shorter disease duration, baseline prednisolone use, lower baseline SR, lower baseline fatigue level, and university/college education were independent predictors of achieving EULAR good response in patients with new-onset RA starting MTX in a real life setting.
Disclosure of Interest None Declared