Objective. We aimed to investigate whether persistence rates of Tumor necrosis factor (TNF) blockers in the early period was affected by the change in reimbursement guideline of Rheumatoid Arthritis (RA) using Korean National Health Insurance (NHI) claims database.
Methods. We identified patients with a diagnosis code of RA between January 2007 to December 2009 and who were 16 years of age or older, in a Korean NHI claims database. A subgroup RA patients who had recently started TNF blockers with 6 months of washout period in June 2007 (n=40), June 2008 (n=60), January 2009 (n=52) and June 2009 (n=68) were selected to compare the 6 months persistence rate. Also, we analyzed a change in prescriptions of TNF blockers in patients with RA for each 6 month period between 2007 and 2009.
Results. The persistence rates of TNF blockers during 6 months in each group was not statistically significant (67.5%, 75.0%, 73.1%, and 79.4%, p=0.22). However, when we compared the frequency of new patients started on TNF blockers in June 2009 to those in the same months in 2008 and 2007; there was a tendency to increase. During change in TNF blocker prescriptions between 2007 and 2009, the overall utilization of TNF blockers increased.
Conclusion. The persistence rate of TNF blockers in the early period was not affected by change of reimbursement guidelines of RA. However, long-term design and multivariate analysis will be needed to identify the impact of change in reimbursement guideline on the persistence of TNF blockers.

Keywords: Rheumatoid arthritis, TNF blocker, Persistence