National pharmacological treatment trends for ankylosing spondylitis in South Korea: A national health insurance database study

No studies of the current status of treatment options are available for ankylosing spondylitis (AS) patients in South Korea. This study assesses the current status of AS treatment trends using a nationwide database. This study was conducted using a Korean National Health Insurance System (KNHIS) dataset from 2006 to 2016. We randomly extracted 50% of the total number of patients registered as As patients in the KNHIS. The distribution of the number of patients according to age and gender was analyzed each year. The types and combination methods of drugs used during the study period were estimated yearly. Between 2006 and 2016, the number of AS patients increased linearly by an average of 9% annually, 6372 in 2006 to 15188 in 2016. The study found that the use of nonsteroidal anti-inflammatory drugs (NSAIDs) was the most commonly prescribed pharmacological treatment option, followed by disease-modifying anti-rheumatic drugs (DMARDs) and then biologics. Biologics such as tumor necrosis factor alpha (TNF-α) inhibitors increased from 10% to 35% consistently for 10 years. In terms of combination therapy, DMARDs + NSAIDs accounted for almost 90% of treatments in 2006, but decreased by 65% in 2016. The use of biologics and NSAIDs increased from 3% to 28%. Prescriptions for dual therapies and mono therapies largely dominated prescription habits, accounted for up to approximately 80% of treatments. Among 10- to 14-year-old patients, there was no triple therapy, dual and triple therapies decreased gradually for those 60 and older, and the ratio of conservative treatments has increased. This study shows how South Korea reflects changes in AS treatment trends, along with the emergence of TNF-α inhibitors that are effective in treating AS. Research on clinical outcomes for AS treatments will be needed on following these drug changes.