Objective. There are currently limited treatment options for rheumatoid arthritis (RA) patients with chronic hepatitis B (CHB). In the process of pursuing further treatment strategies for this subgroup of patients, it is prudent to study what medications have been commonly prescribed, particularly for disease modifying anti-rheumatic agents (DMARDs) in Korea.
Methods. We analyzed the Korean National Health Insurance claims database (2007∼2009) of RA patients through co-working with the Clinical Research Center for RA (CRCRA). Patients with CHB were defined by an algorithm including prescription information, blood tests, and the ICD-10 code.
Results. There were 8,677 CHB patients (3.8%) among 226,592 RA patients in the database. The age distribution or gender difference in CHB patients was comparable to the general RA population. Hydroxychloroquine was the most frequently (66.2%) prescribed DMARD. Thirty four percent of CHB patients had been prescribed with methotrexate (MTX) during the study period; most of them without concomitant anti-viral treatment. About 3% of RA patients with CHB were prescribed with TNF inhibitors.
Conclusion. Apart from the published expert recommendations, MTX still seems to be one of the main DMARDs prescribed to Korean RA patients with CHB. This is most likely due to the lack of evidence-based, effective treatment strategies for this subgroup of patients.

Keywords: Rheumatoid arthritis, Chronic hepatitis B, Methotrexate, Treatment