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 a well-established prospective, population based inception cohort. Our aim was to analyze total, age and gender specific incidence and prevalence rates of ulcerative colitis (UC) patients over the past four decades (1977-2018). Methods Data of 1,370 UC 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 Adjusted mean incidence rate of UC increased from 4.06 (CI95%: 2.47-6.66) /105 person-years in 1977-1991 to 13.31 (CI95%: 10.71-17.50) /105 in 1997-2001. The following years show a plateau/ slight decrease in incidence: 11.16 (CI95%: 8.18-15.23) /105 in 2007-2011 and 10.92 (CI95%: 7.98-14.96) /105 in 2012-2018. see Figure 1/A. Age specific mean incidence rates in the total cohort show a peak of disease onset at the age of 20-29 years (16.54 /105 person-years), however incidence is only slightly lower at the age of 30-39 years (15.82 /105 person-years). The total prevalence of UC patients show a steady increase from 60.05 (CI95%: 52.07-68.42) /105 persons in 1991 to 317.62 (CI95%: 299.62-336.70) /105 in 2015. Age specific prevalence rates show similarly high prevalence rates among elderly patients (60-69y) compared to adult patients, meaning a saturation of age specific curves in the elderly. see Figure 1/B. Age specific prevalence of UC among the 60-69 years old is as high as 506.42 (CI95%: 443.23-578.56) /105 persons in 2015. Conclusion Incidence rates of UC patients plateaued around the 2000s and show slight decrease afterwards. Prevalence rates of UC show a steady increase, thus Hungary is well into the 3rd epidemiological phase of compounding prevalence. As we already see a saturation of prevalence rates among elderly UC patients, a transition to the 4th stage of prevalence equilibrium may began. 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 Akos, Ilias: 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 Lakatos, Laszlo: No conflict of interest Lakatos, Péter Laszlo: No conflict of interest
Gönczi et al. (Thu,) studied this question.