P585. Treatment paradigm and natural course of ulcerative colitis between 1977–2012: a hospital-based cohort study from Korea
Until now, no large-scale studies have evaluated the prognosis of ulcerative colitis (UC) over a period of three decades in non-Caucasian populations. The aims of this study were to update the current information on the natural course of UC using a large series of patients and to evaluate changes in treatment paradigms over time and the prognosis of UC in Korea.
We retrospectively analyzed 2,497 Korean UC patients who visited the Asan Medical Center. The study subjects were divided into three groups according to the year of diagnosis (cohort 1: 1977–2000, cohort 2: 2001–2005, and cohort 3: 2006–2012).
The male-to-female ratio was 1.2:1 and the median age at diagnosis was 36 years (range, 9–90 years). The median duration of follow-up was 88 months (range, 0.1–433 months). Azathioprine/6-mercaptopurine and anti-tumor necrosis factor (anti-TNF) agents have been used increasingly more frequently and earlier over the last 30 years, with a 5-year cumulative probability of prescription of 5.5% and 0.0%, respectively, in cohort 1 and 26.5% and 9.9%, respectively, in cohort 3 (p < 0.001). A total of 206 patients (8.2%) underwent total proctocolectomy, with a cumulative probability of total proctocolectomy 10, 20, and 30 years after diagnosis of 8.7%, 15.5%, and 24.2%, respectively. The cumulative probability of colectomy was significantly lower in patients first diagnosed in our center (n = 496) than in patients referred from primary clinics or other hospitals (n = 2001) (2.9% vs. 10.1% at 10 years and 4.5% vs. 18.0% at 20 years, p < 0.001). In patients first diagnosed in our center, the cumulative probability of colectomy was significantly lower in cohort 3 than in cohort 1 (p = 0.042).
Our study demonstrated that thiopurines and anti-TNF agents have been used increasingly over the years as has been observed in the Western population. The colectomy rate has decreased over time in patients first diagnosed in our institution (i.e. excluding referral bias). Korean UC patients, especially first diagnosed in our institution may have better clinical courses than Westerners, as indicated by the lower colectomy rate.
This study was supported by a grant of the Korean Health Technology R&D Project, Ministry of Health & Welfare, Republic of Korea (A120176).