P1264 Evolution of epidemiological stages of Crohn’s disease in Hungary – trends of age and gender specific incidence and prevalence from a population-based cohort between 1977–2018

Abstract Background The evolution of inflammatory bowel disease (IBD) occurs across four epidemiological stages: emergence, acceleration in incidence, compounding prevalence and prevalence equilibrium; as put forward by Kaplan. et al. (Nat Rev Gastroenterol Hepatol. 2021). Newly industrialized countries are in the acceleration in incidence stage, while the western world is in the compounding prevalence stage: stable incidence and rapidly increasing prevalence. The Veszprém IBD cohort is one of the very few well-established prospective, population based inception cohorts worldwide, capable of delivering reliable epidemiological data. Our aim was to analyze total, age and gender specific incidence and prevalence rates of Crohn’s disease (CD) patients over the past four decades (1977-2018). Methods Data of 946 CD patients were analyzed. Patient inclusion was between January 1, 1977 and December 31, 2018. All patients in Veszprem county, a well-defined administrational area of Hungary, was included. Both in-hospital and outpatient records were collected and comprehensively reviewed at diagnosis and during clinical follow-up. The source of age- and gender-specific demographic data for statistical analysis was derived from the results of a national population census in 1980, 1990, 2001 and 2011 (source: Hungarian Central Statistical Office). Prevalence rates were calculated in 1991, 2001, 2011 and 2015. Results Mean incidence rate of CD showed steady increase from 1.44 (CI95%: 0.64-3.27) /105 person-years in 1977-1991 to 10.59 (CI95%: 7,70-14,57) /105 in 2007-2011. Incidence showed no further elevation in 2012-2018 (9.46 (CI95%: 6.76-13.27) /105 person-years). see Figure 1/A. Age specific mean incidence rates in the total cohort show a clear peak at the age of 20-29 years (18.13 /105 person-years). The total prevalence of CD patients increases steadily from 17.35 (CI95%: 13.62-22.18) /105 persons in 1991 to 230.58 (CI95%: 215.31-246.94) /105 in 2015. Age specific prevalence rates show highest prevalence among the 30-39 years old in 2015 (422.02 (CI95%: 371.19-479.79) /105 persons). Prevalence rates are still significantly lower in the elderly (60-69y: 167.80 (CI95%: 133.07-211.59) /105 persons). see Figure 1/B. Conclusion Incidence rates of CD rose steadily until the 2010s and may start a plateau phase thereafter. Prevalence rates of CD show a steady increase over the study period, thus Hungary is probably entering the 3rd epidemiological phase of compounding prevalence. Age specific prevalence rates peak at the age of 30-39 years and decrease in the elderly, as opposed to ulcerative colitis (UC). Conflict of interest: Gonczi, Lorant: No conflict of interest Angyal, Dorottya: No conflict of interest Balogh, Fruzsina: No conflict of interest Golovics, Petra: No conflict of interest Pandur Baloghne, Tunde: No conflict of interest David, Gyula: No conflict of interest Erdélyi, Zsuzsanna: No conflict of interest Szita, Istvan: No conflict of interest Akos, Ilias: No conflict of interest Lakatos, Laszlo: No conflict of interest Lakatos, Péter Laszlo: No conflict of interest