P1197Ethnic Differences in Inflammatory Bowel Disease (IBD): A Single-Center Comparative Study Between Italian and Immigrant Patients

Abstract Background The etiology of inflammatory bowel disease (IBD) remains incompletely understood, involving complex interactions among genetic, environmental, and immunological factors. While IBD is more common in Western countries, incidence and prevalence have risen in historically low-incidence regions, likely driven by Westernization and industrialization, with lifestyle, dietary, and environmental shifts. This study compared two cohorts of IBD patients—Italian-born individuals from Emilia-Romagna and immigrants—to evaluate differences in clinical presentation, disease course, and treatment response. Methods This ambi-prospective study included 258 patients followed at the IBD Unit of the University Hospital of Modena. The migrant cohort comprised 86 patients born outside Italy; the comparison cohort included a 2:1 sex-, age-, and disease type–matched sample of Italian-born patients from Emilia-Romagna. Clinical history, endoscopic findings, and treatment data were collected at diagnosis and last follow-up. Descriptive and inferential analyses were performed using STATA. Results Among Crohn’s disease (CD) patients, no significant differences in disease behavior were observed (p = 0.358), although penetrating phenotype was more frequent among migrants. Disease localization differed significantly at diagnosis (migrants: ileocolic 51.11% vs Italians: ileal 46.67%; p = 0.009) and at endoscopic follow-up (p = 0.02). Clinical evolution was comparable (regression in 66.67% of Italians vs 55.56% of migrants; p = 0.505). In ulcerative colitis (UC), extended disease was more common among Italians (p = 0.377). Moderate disease at diagnosis was prevalent in both groups (Italians 50%, migrants 60.53%; p = 0.158). At follow-up, endoscopic remission (e-Mayo 0) was significantly more frequent in Italians (49% vs 28.12%; p = 0.001), whereas 50% of migrants had moderate activity (e-Mayo 2). Surgical intervention was more common in Italians (25% vs 17.44%; p = 0.170). No differences emerged regarding major extraintestinal manifestations (p = 0.281). Current therapy differed (p = 0.042), with 5-ASA more frequently used among migrants (52.33% vs 34.30%). Biologic therapy rates were comparable, though Italians were more likely to undergo multiple treatment switches (2 switches: 17.54% vs 8.14%; p = 0.042). The median number of flare-ups was similar (2; p = 0.257). Conclusion This study identified clinically relevant differences between Italian and immigrant IBD patients. Ethnic and migration background appeared to influence disease phenotype, and therapeutic strategies. While overall disease progression was similar, notable differences emerged in treatment response and endoscopic remission rates. Further studies are needed to validate these findings. References: Loftus EV. Clinical epidemiology of inflammatory bowel disease: incidence, prevalence, and environmental influences. Gastroenterology. 2004;126(6):1504-1517. doi:https://doi.org/10.1053/j.gastro.2004.01.063 Barreiro-de Acosta M, Alvarez Castro A, Souto R, Iglesias M, Lorenzo A, Dominguez-Muñoz JE. Emigration to western industrialized countries: A risk factor for developing inflammatory bowel disease. Journal of Crohn’s and Colitis. 2011;5(6):566-569. doi:https://doi.org/10.1016/j.crohns.2011.05.009 Fiorino G, Estevinho MM, Lopes DJM, et al. Inflammatory Bowel Disease in Migrant Populations: Should we Look Even Further Back? Current Drug Targets. 2021;22(15):1706-1715. doi:https://doi.org/10.2174/1389450122666210203193817 Conflict of interest: Pecchini, Maddalena: No conflict of interest Bertani, Angela: Lilly, Abbvie,Takeda,Pfizer, Ferring, Alfa sigma, J&J, Francia, Chiara: No conflict of interest Christou, Chrysanthi: No conflict of interest Lei, Barbara: No conflict of interest Sandri, Gilda: No conflict of interest Amati, Gabriele: No conflict of interest Colecchia, Antonio: No conflict of interest