AB0274 METHOTREXATE INTOLERANCE IN MOROCCAN RHEUMATOID ARTHRITIS PATIENTS

Background: Methotrexate intolerance is a principal reason for treatment discontinuation, hence the interest in a more in-depth study. Objectives: We aimed to study the prevalence of methotrexate gastrointestinal intolerance and determine its associated factors in rheumatoid arthritis (RA) patients. Methods: We designed a cross-sectional study on our RA patients recruited in January 2021 at our rheumatology department. Methotrexate Intolerance Severity Score (MISS) [1], previously validated in juvenile idiopathic arthritis patients, was used to determine methotrexate (MTX) intolerance prevalence in RA patients. The MISS consisted of four domains: abdominal pain, nausea, vomiting, and behavioral symptoms, occurring before (anticipatory), after, and when thinking of MTX (associative). MTX intolerance was defined as six or more points on the MISS. Our statistical analysis was based on a descriptive study and logistic regression with SPSS20. Results: We included 102 RA patients with a mean age of 51.60 ± 14.33 years, Women were predominant (93.1%). The mean disease duration was 14.86 ± 9.78 years, with a mean methotrexate use duration of 7.42 ± 6.44 years. The mean dose of methotrexate was 12.13 ± 9.06 mg per week. The prevalence of methotrexate intolerance was 55.9%, and seventy-six patients (74.5 %) experienced at least one gastrointestinal symptom during MTX treatment. After MTX administration, the most prevalent gastrointestinal symptom was nausea (93% of the intolerant patient), whereas abdominal pain occurred in 73.7% and vomiting in 57.9%. These symptoms were also prevalent before and when thinking of MTX. Anticipatory nausea was reported in 45.6% and associative nausea in 54.5% of the cases, abdominal pain occurred anticipatory in 22.8% and associative in 42.1 %, anticipatory vomiting was the least prevalent, affecting 8.8 %. Behavioral symptoms affected 87.7% of intolerant patients, with restlessness being the most prominent symptom in 71.9% of them. Among the intolerant patients, 45 patients (79%) took parenteral MTX, and 12 (21.1%) took methotrexate orally. In comparison, young patients (49.11 ± 14.95 years) were more intolerant to MTX than old (54.76 ± 13 years, p = 0.048) ones. However, in univariate logistic regression analysis, we did not find any significant association between methotrexate administration route, dose, duration, and digestive intolerance. Conclusion: Methotrexate intolerance was highly prevalent in our RA population. These results strengthen the idea that early detection of MTX intolerance may avoid effective treatment discontinuation, especially in younger patients. References: [1]Bulatovic M, Heijstek MW, Verkaaik M, van Dijkhuizen EH, Armbrust W, Hoppenreijs EP et al. High prevalence of methotrexate intolerance in juvenile idiopathic arthritis: development and validation of a methotrexate intolerance severity score. Arthritis Rheum. 2011 Jul; 63(7):2007-13. Disclosure of Interests: None declared