Trends in treatment for patients with late-onset rheumatoid arthritis in Japan: Data from the NinJa study.

Objectives: Our objective was to investigate trends in the treatment of patients with late-onset rheumatoid arthritis (LORA) using data from the National Database of Rheumatic Diseases in Japan (NinJa).

Methods: Patients registered in the National Database of Rheumatic Diseases in Japan were classified according to the disease onset: at <65 years (young-onset rheumatoid arthritis); at 65-74 years (early LORA); and at ≥75 years (late LORA). Chronological changes in the treatment and disease activity were compared.

Results: A total of 7178, 13,171, 15,295, and 15,943 patients were evaluated in 2010, 2013, 2016, and 2019, respectively. In all groups, the use of methotrexate gradually decreased, whereas that of biological/targeted synthetic disease-modifying antirheumatic drugs (DMARDs) increased; the use of tumor necrosis factor inhibitors decreased, whereas that of non-tumor necrosis factor inhibitors increased. LORA was characterized by more single DMARD use and less methotrexate and biological/targeted synthetic DMARD use. Tumor necrosis factor inhibitors and interleukin-6 inhibitors were used less frequently, whereas abatacept was utilized more frequently in late versus early LORA. Conventional synthetic DMARD (excluding methotrexate) and glucocorticoid use was higher in late versus early LORA.

Conclusions: This analysis revealed chronological changes in the treatment of LORA in Japan. Differences between early and late LORA suggest that patients are not a homogeneous population.