AB0252 INTOLERANCE TO METHOTREXATE IN RHEUMATOID ARTHRITIS: AN ASSESSMENT WITH THE MISS (METHOTREXATE INTOLERANCE SEVERITY SCORE)

Abstract

BackgroundMethotrexate (MTX) is a cornerstone in the treatment of rheumatoid arthritis (RA), in monotherapy or in combination with biological agents. Its prolonged use requires regular clinical and biological monitoring. The purpose of our study is to assess intolerance to MTX and its consequences.ObjectivesThe purpose of our study is to assess intolerance to MTX and its consequences.MethodsThis is a cross-sectional study with RA follow-up patients meeting the ACR/EULAR 2010 criteria. An assessment of MTX intolerance was conducted using the Arabic version of the MISS (Methotrexate Intolerance Severity Score). It is a questionnaire containing 12 items covering four areas: abdominal pain, nausea, vomiting and behavioral disorders. A score of six indicates an intolerance.ResultsForty patients were included: 35 women (87.5%) and 5 men (12.5%) of average age 51.7 years ±12.7 years. The average duration of disease progression was 12.2 years 9.2 [1-40 years]. All patients were treated with methotrexate and supplemented with folic acid. 50% of patients were under 10mg/week of MTX, 27.5% under 15mg/week and 22.5% under 20 mg/week. Patients had been on this treatment for an average of 8.7 years [1-25 years]. The majority of them (97.5%) received corticosteroids in combination, 12.5% received Salazopyrine and 27.5% received biotherapy. Methotrexate intolerance was observed in 16 patients (42.1%). Nausea was observed in 13 patients (81.2%), vomiting in 5 patients (31.2%), abdominal pain in 11 patients (68.8%) and behavioral disorders in all patients. As a result of this intolerance, 18.8% of patients had to stop their treatment, 12.5% decreased the dose on their own, 6.2% took the MTX irregularly, 12.5% switched from the oral route to the intramuscular route and 50% continued to take their treatment in the usual way. The study of correlations did not reveal statistically significant associations between MTX intolerance and age, sex, dose and duration of MTX, the associated intake of salazopyrin, biotherapy and other symptomatic treatments.ConclusionThe occurrence of an intolerance to MTX is common in patients followed for RA, which may lead to poor adherence to therapy or even a discontinuation of treatment thus decreasing the effectiveness of management. Hence the need to systematically detect this intolerance and react in time.Disclosure of InterestsNone declared