Assessment of 5-Aminosalicylic Acid Prescription Patterns and Treatment Outcomes in Patients With Ulcerative Colitis in Korea

The prevalence of ulcerative colitis (UC), which is one of the inflammatory bowel diseases, is known to be increasing and the majority of patients (≥ 85%) have experienced mild or moderate severity. 5-Aminosalicylic acid (5-ASA), immunomodulator, or biologics, etc are prescribed to treat UC, however 5-ASA is generally considered the first-line therapy. The recent UC treatment guideline in Korea and the United States/ European Union (US/EU) have recommended higher daily dose for patients with mild or moderate severity than the previous guidelines since 2017. Accordingly, it is assumed that the average daily treatment dose of 5-ASA would increase in patients who were initially diagnosed with UC in real-world clinical practice in Korea. However, there are not many studies evaluating the treatment patterns and health outcomes of 5-ASA based on the recent treatment guideline in South Korea. This study, hence, aims to investigate the impact of changes in daily dose of 5-ASA on the treatment patterns and health outcomes such as recurrence rate, hospitalization rate, and surgery rate in real world practice using Health Insurance Review and Assessment (HIRA) claims database.