Pôster:

Methotrexate (MTX) is an anchor drug indicated for the treatment of RA but gastrointestinal intolerance can preclude its benefits. The aim of the study was to determine the frequency of methotrexate intolerance in patients with rheumatoid arthritis using the methotrexate intolerance severity score (MISS), a tool validated for the Portuguese language, and to determine factors associated with intolerance.

Materials and methods

A descriptive study, non-probabilistic sample, was performed at a Brazilian rheumatology service. The questionnaire contains 12 questions in four domains: Abdominal pain, nausea, vomiting and behavioral symptoms. The instrument has questions regarding the presence of symptoms before the use of the medication (anticipatory) and when thinking about the intake of MTX (associative). MTX intolerance was defined as a score ≥6 points, with at least one point of anticipatory and/or associative and/or behavioral symptoms. Demographic and clinical characteristics were collected from medical records.

Results

One hundred and twenty patients with RA using stable dose of MTX for at least three months were selected to respond to the MISS questionnaire, one hundred and three (85.8%) patients were female, on average, sixty-one years, with a standard deviation of 12.5; sixty-six (55.0%) used subcutaneous MTX, eighty-eight (73.4%) were on 20 mg or more; sixty-three (52.5%) were on glicocorticoid; fifteen (12.6%) are smokers. From the total of participants, forty-one (34.2%) reported the presence of behavioral symptoms, thirty-five (29.2%) received scores on associative symptoms and twenty-seven (22.5%) presented points of anticipation. Twenty-six (21.7%) subjects presented intolerance to MTX. The most prevalent symptom among intolerants after MTX was nausea twenty-four (92.3%), followed by abdominal pain twelve (42.3%) and vomiting eight (30.7%). The pre-treatment symptoms most prevalent in intolerant patients were associative twenty-two (84.6%) and the anticipatory eighteen (69.2%) in the nausea domain. The behavioral symptoms occurred in twenty-five (96.1%). Patients who use glicocorticoid have three times the chance of being intolerant than patients who do not use (IC95%: 1.06 a 7.06). Each year increase in age reduced by 3% (OR = 1/0.97; IC95%: 0 a 7) the chance of MTX intolerance.

Conclusion

MTX intolerance presents moderate prevalence in patients with RA, the occurrence of anticipatory, associative and behavioral symptoms are very frequent and present an important role in the diagnosis of MTX intolerance. In addition, our findings indicate that patients who use glicocorticoid are more likely to be intolerant and with increasing age, patients tend to be less likely to be intolerant.