Use of oral and subcutaneous methotrexate in rheumatoid arthritis patients in the United States.

Abstract

To examine the patterns of methotrexate (MTX) use among rheumatoid arthritis (RA) patients. Using data from RA patients enrolled in a US commercial health plan and the US Medicare program, we identified RA patients initiating oral MTX. Persistence with MTX (oral or subcutaneous [SC]) was defined as no gap for ≥90 days. New oral MTX users in Medicare (n = 20,431) were 76.9% women, had a mean ± SD age of 69.7 ± 11.7 years, and contributed a median followup of 2.6 years (interquartile range 1.7-3.5 years). Only 38% received dosages ≥20 mg/week at any time. Approximately 50% of patients discontinued MTX at 1 year, although more than one-third of patients subsequently restarted. New commercially insured oral MTX users (n = 4,048) were similar to Medicare patients, except for age. Among Medicare patients, 19% starting oral MTX subsequently initiated a biologic agent, mostly anti-tumor necrosis factor (85%). Of these, only 50% received MTX at a dosage of ≥20 mg/week, and only 21% of individuals switched to SC MTX (4%) or received hydroxychloroquine (8%), sulfasalazine (5%), or leflunomide (8%) prior to biologic agents. In commercially insured patients, 35% initiated a biologic agent, mostly anti-tumor necrosis factor therapies (90%). Of these, 43% never received MTX ≥20 mg/week. Titration to a higher-dose oral MTX and use of SC MTX among RA patients were infrequent and may have been underutilized. Further work to optimize MTX dosing before patients are switched to a biologic agent may be warranted.