Long-term persistence of oral methotrexate and associated factors in rheumatoid arthritis: a retrospective cohort study.

There is little data on long-term persistence/continuation of methotrexate among Indian Rheumatoid arthritis patients. We assembled a retrospective single-center cohort consisting of RA patients (fulfilling 1987 ACR criteria) started on methotrexate as part of three academic studies (including two RCTs) from 2011 to 2016. Oral methotrexate was started at 7.5 or 15 mg per week with a target dose of 25 mg per week. Between August and December 2020, all patients were contacted (telephonically) and data were obtained from clinic files to evaluate self-reported continuation/persistence of methotrexate and reasons for discontinuation. Survival analysis using Kaplan-Meier and cox-regression were used to assess methotrexate continuation rates and factors associated with its discontinuation. This study included 317 patients with rheumatoid arthritis, with mean age and disease duration (at enrollment) of 43 years and 2 years; And positive rheumatoid factor and anti-CCP in 69 and 75%. At follow-up, 16 patients (5%) had died, whereas 103 (32.5%) had discontinued methotrexate. On Kaplan-Meier survival analysis, the mean survival (continuation) time for methotrexate was 7.3 years (95% CI 7-7.6 years). The actuarial continuation/persistence of methotrexate at 3, 5 and 9 years was 92, 81 and 51%, respectively. Among those who discontinued methotrexate, common reasons were remission of disease, symptomatic adverse effects (intolerance), perceived lack of efficacy and socioeconomic reasons. On multivariable cox-regression, symptomatic adverse effects during the first 12-24 weeks (Hazard ratio, 95% CI 1.8 (1.2-2.8)) and anti-CCP positivity (Hazard ratio, 95% CI 0.6 (0.3-1.0)) were significantly associated with hazard of discontinuation. Persistence or continuation of methotrexate was found to be good and comparable to reports in other centers world-wide. Apart from remission, the most important cause of methotrexate discontinuation was symptomatic adverse effects (intolerance).