Relationship between frailty and methotrexate discontinuation due to adverse events in rheumatoid arthritis patients

Introduction Methotrexate (MTX) is an anchor drug in the treatment of rheumatoid arthritis (RA). Frailty is the intermediate condition between being healthy and disabled, and can lead to negative health outcomes. Adverse events (AEs) due to RA drugs are expected to be higher in frail patients. The present study aimed to investigate the relationship between frailty and MTX discontinuation due to AEs in RA patients. Methods Of 538 RA patients who visited us between June and August 2020 as part of the retrospective T-FLAG study, 323 used MTX. After 2 years of follow-up, we investigated AEs leading to MTX discontinuation. Frailty was defined as a Kihon Checklist (KCL) score ≥ 8. Cox proportional hazards regression analysis was performed to identify factors associated with MTX discontinuation due to AEs. Results Of the 323 RA patients (251 women, 77.7%) who used MTX, 24 (7.4%) discontinued MTX due to AEs during the 2-year follow-up period. Mean ages in the MTX continuation/discontinuation groups were 64.5 ± 13.9/68.5 ± 11.7 years ( p = 0.169), Clinical Disease Activity Index was 5.6 ± 7.3/6.2 ± 6.0 ( p = 0.695); KCL was 5.9 ± 4.1/9.0 ± 4.9 points ( p