Background Disease Modifying Antirheumatic Drugs (DMARDS) are the cornerstone in the pharmacological options for treatment of patients with rheumatoid arthritis. Recent statements from the American College of Rheumatology recommend methotrexate (MTX), sulfasalazine or leflunomide as initial treatment options. Such treatments have proved to be equally effective but there are no guidelines to choose one over another as monotherapy.
Objectives We aimed to determine the factors associated to good response with the use of leflunomide in patients naïve to this treatment.
Methods We performed a retrospective search within the registries of our health system of patients with clinical diagnosis of rheumatoid arthritis. We included patients older than 18 years up to 65, with at least 6 months of diagnosis who had received leflunomide, with following for at least one year after de initial dose of leflunomide. The primary outcome was good response defined as remission or low activity (DAS28 <2.6 and <3.2, respectively) at 6 and 12 months; we compared these patients with those who did not achieved the outcome. Demographic, disease characteristics and laboratory variables were analyzed according Chi or U Mann Whitney tests depending on the category. A binomial logistic regression analysis was also performed. We considered a p<0.05 as statistically significant.
Results We found 234 patients who were on leflunomide treatment but only 101 fulfilled the criteria. 95% were women, mean age 50±14.2 years; mean duration of disease was 29 months. 74% patients had not previously used DMARDS (mainly methotrexate); mean disease activity score (DAS28) was 4.66±1.17 (no difference between previous DMARD users and non-users). There were no difference in good response among previous DMARD users and non-users; no difference between those who received. Patients with lower DAS28 score, ERS and platelet counts achieved higher rates of good response (p 0.001) at 6 months. Those with higher hemoglobin levels, lower platelet counts and lower physician global assessment (PGA) maintained good response rate at 12 months. We found a strong association with good response and lower ESR [OR 0.94, IC 95% (0.90-0.97)] and lower platelet counts [OR 0.99, IC 95% (0.98-0.99)]; p<0.001.
Conclusions We found that patients with rheumatoid arthritis who had lower activity scores, lower levels of ESR and lower platelet counts, independently of previous DMARD-use, achieved good response at 12 months. This could help the clinician to better choose the patients who might have more benefit from the use of leflunomide.
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Disclosure of Interest None declared