Epidemiology of ulcerative colitis and Crohn’s disease: analytical data from the first regional registry of inflammatory bowel diseases of Saint Petersburg based on the state health information system

Introduction. Inflammatory bowel diseases (IBD), which include ulcerative colitis and Crohn’s disease, are an urgent problem of modern gastroenterology, as they have a chronic progressive course, affect people of working age and require long-term and expensive therapy. The aim of the study: to conduct a population-based assessment of epidemiologic and demographic indicators of IBD in the region as a whole, as well as to estimate the burden on the regional health care system due to this pathology. Study results. The average annual incidence of ulcerative colitis calculated from the data of the IBD registry was 37 cases per 100,000 population, the average annual incidence of Crohn’s disease was 29 cases per 100,000 population. The calculated prevalence of ulcerative colitis was 157 per 100,000 population, and the prevalence of Crohn’s disease was 140 per 100,000 population. The average annual mortality rate due to IBD was 0.4 cases per 100,000 population and 1.7 cases per 1,000 patients with IBD, with fatal complications occurring on average 2.4 times more frequently in the debut of IBD compared to the period after the diagnosis. 65.7% of patients with ulcerative colitis and 70.7% of patients with Crohn’s disease were between 18 and 59 years of age. Women (55.7%) prevailed among patients with IBD, which corresponded to the gender demographic features of the region as a whole. Between 2019 and 2024, there was a year-on-year increase in both the number of patients with IBD presenting to healthcare facilities in the region and the number of referrals. In 2024, nearly half of the region’s adult patients with IBD were observed at the region’s two specialized IBD state medical centers, with annual increases in caseloads at the specialized IBD state medical centers between 2021 and 2024. Conclusion. The first population-based regional registry of IBD of St. Petersburg made it possible for the first time to conduct a long-term population-based assessment of all key epidemiological and demographic indicators of IBD on the country region as a whole, as well as to evaluate the burden on the regional health care system and the actual routing of patients with this pathology. Calculation of average annual indicators allowed to ensure the validity of the calculated values. The obtained data will be used for planning the provision of specialized medical care to patients with IBD.