OP09 Long-term Colectomy rates of Ulcerative Colitis over 40-year of Different Therapeutic eras – Results from a Western Hungarian Population-based Inception Cohort between 1977–2020

Abstract

Abstract Background Few population-based studies have investigated the long-term colectomy rates of ulcerative colitis (UC). The present study is a continuation of the Veszprem IBD population based cohort with a follow-up of the incidence and disease course for over 40 years. We aimed to assess the colectomy rates over 40 years of different therapeutic eras in a prospective population-based inception cohort from Veszprem Province, Western Hungary. Methods Patient inclusion lasted between January1,1977 and December31, 2018. Patient follow-up ended December 31,2020. Both in-hospital and outpatient records were collected and comprehensively reviewed at diagnosis and during clinical follow-up. Disease extension was evaluated based on the Montreal classification. Colectomy rates and disease course were examined in three different eras based on the time of UC diagnosis; cohort-A(1977-1995),cohort-B(1996-2008), and cohort C(2009-2018). Results Data of 1,370 incident UC patients were analyzed (male/female: 702/668; median age at diagnosis: 37 years(y) [IQR: 26-51]), with a median of 17y (IQR 9-24) follow-up. Table 1. The overall colectomy rate was 76/1,370 patients during the total follow-up. The proportion of extensive colitis at diagnosis increased over time (24.2% / 24.3% / 34.9% in cohorts A/B/C; p=0.001). Overall immunosuppressive therapy exposure was increasing in the cohorts (11.3% / 20.9% / 34.4%; p<0.001), as well as the probability of biological therapy initiation within 5 years of diagnosis (0.0±0% / 3.3±0.7% / 13.9±1.8%; pLogRank<0.001). Figure 1. There was no significant difference in the cumulative probability of proximal disease progression from proctitis (E1) to left-sided colitis/extensive colitis (E2/E3) or from left-sided colitis (E2) to extensive colitis (E3) over time in cohorts A, B, and C (Long-rank=0.482). Figure 2. The cumulative probability of colectomy in the total population was 4.1±0.6% after 10 years, 6.3±0.8% after 20 years, and 8.8±1.2% after 30 years. There were no statistically significant differences in the cumulative probability of colectomies between cohorts A/B/C: 1.7±0.7% / 2.2±0.6% / 3.7±1.0% after 5 years; 3.5±1.0% / 3.9±0.8% / 4.5±1.2% after 10 years; and 6.9±1.4% / 5.3±1.0% (cohorts A/B) after 20 years [pLogRank=0.447]. Figure 3. Extensive disease (HR 2.3;95%CI 21.60-3.37) and continuous uncontrolled disease activity (HR 6.89;95%CI 4.15-11.46) were independent predictors for colectomy. Table 2. Conclusion No differences in proximal disease progression and colectomy rates have been observed in the incident UC patients over 40 years despite increasing use of immunomodulators and biological therapies.