A decade of inflammatory bowel disease: Insights from a tertiary referral center in Bulgaria

Abstract

Introduction: In Bulgaria, the absence of comprehensive national data poses challenges for both clinicians and healthcare authorities.

Objectives: The aim of this retrospective study was to analyze the epidemiological characteristics of inflammatory bowel disease (IBD) over a 10-year period at a leading university referral center serving the northeastern, north-central, and southeastern regions of Bulgaria.

Methods: A total of 722 adult patients aged 18-75 years were included in the cohort. All patients were treated over a 10-year period at the Referral IBD Center of the Clinic of Gastroenterology, University Multiprofile Hospital for Active Treatment “St. Marina,” Varna, Bulgaria.

Results: In the northeastern region of Bulgaria, the mean annual crude incidence was 1.72 per 100,000 population, and the mean annual crude prevalence during 2013-2022 was 13.86 per 100,000. In the north-central region of Bulgaria, the mean annual crude incidence was estimated at 0.41 per 100,000 population, and the mean annual crude prevalence during 2013-2022 was 3.12 per 100,000 population. In the southeastern region of Bulgaria, the mean annual crude incidence was 0.15 per 100,000 population. During the 2013-2022 period, the annual prevalence in this region ranged from 0.95 to 1.90 per 100,000 population.

Conclusion: The results of the present study indicate a consistent trend of increasing incidence of IBD, which is likely due both to a genuine rise in disease prevalence and to advancements in diagnostic technologies. This study provides valuable data on the epidemiology of IBD for the first time in Bulgaria.

Keywords

Inflammatory bowel disease / Incidence / Prevalence / Bulgaria

References

[1] Burisch J, Katsanos KH, Christodoulou DK, et al. Natural disease course of ulcerative colitis during the first five years of follow-up in a European population-based inception cohort-An Epi-IBD study. J Crohns Colitis. 2019; 13(2):198-208. doi: 10.1093/ecco-jcc/jjy154

[2] Sturm A, Maaser C, Mendall M, et al. European Crohn’s and Colitis Organisation topical review on IBD in the elderly: Table 1. J Crohns Colitis. 2017; 11(3):263-273. doi: 10.1093/ecco-jcc/jjw188

[3] Zhang YZ, Li YY. Inflammatory bowel disease: pathogenesis. World J Gastroenterol. 2014; 20(1):91-99. doi: 10.3748/wjg.v20.i1.91

[4] Agrawal M, Jess T. Implications of the changing epidemiology of inflammatory bowel disease in a changing world. United Eur Gastroenterol J. 2022; 10(10):1113-1120. doi: 10.1002/ueg2.12317

[5] Caron B, Honap S, Peyrin-Biroulet L. Epidemiology of inflammatory bowel disease across the ages in the era of advanced therapies. J Crohns Colitis. 2024; 18(Suppl 2):ii3-ii15. doi: 10.1093/ecco-jcc/jjae082

[6] Kaplan GG, Windsor JW. The four epidemiological stages in the global evolution of inflammatory bowel disease. Nat Rev Gastroenterol Hepatol. 2021; 18(1):56-66. doi: 10.1038/s41575-020-00360-x

[7] Ng SC, Shi HY, Hamidi N, et al. Worldwide incidence and prevalence of inflammatory bowel disease in the 21st century: a systematic review of population-based studies. Lancet. 2017; 390(10114):2769-2778. doi: 10.1016/S0140-6736(17)32448-0.

[8] Zhao M, Gönczi L, Lakatos PL, Burisch J. The burden of inflammatory bowel disease in Europe in 2020. J Crohns Colitis. 2021; 15(9):1573-1587. doi: 10.1093/ecco-jcc/jjab029

[9] Burisch J, Jess T, Martinato M, Lakatos PL; ECCO-EpiCom. The burden of inflammatory bowel disease in Europe. J Crohns Colitis. 2013; 7(4):322-337. doi: 10.1016/j.crohns.2013.01.010

[10] Panaccione R. Mechanisms of inflammatory bowel disease. Gastroenterol Hepatol. 2013; 9(8):529-532.

[11] Burisch J, Munkholm P. The epidemiology of inflammatory bowel disease. Scand J Gastroenterol. 2015; 50(8):942-951. doi: 10.3109/00365521.2015.1014407

[12] Burisch J, Pedersen N, Čuković-Čavka S, et al. East-West gradient in the incidence of inflammatory bowel disease in Europe: the ECCO-EpiCom inception cohort. Gut. 2014; 63(4):588-597. doi: 10.1136/gutjnl-2013-304636

[13] Vegh Z, Kurti Z, Lakatos PL. Epidemiology of inflammatory bowel diseases from west to east. J Dig Dis. 2017; 18(2):92-98. doi: 10.1111/1751-2980.12449

[14] Loftus EV Jr, Sandborn WJ. Epidemiology of inflammatory bowel disease. Gastroenterol Clin North Am. 2002; 31(1):1-20. doi: 10.1016/S0889-8553(01)00002-4

[15] Lakatos PL. Recent trends in the epidemiology of inflammatory bowel diseases: up or down? World J Gastroenterol. 2006; 12(38):6102-6108. doi: 10.3748/wjg.v12.i38.6102

[16] Kaplan GG. The global burden of IBD: from 2015 to 2025. Nat Rev Gastroenterol Hepatol. 2015; 12(12):720-727. doi: 10.1038/nrgastro.2015.150

[17] Gheorghe C, Pascu O, Gheorghe L, et al. Epidemiology of inflammatory bowel disease in adults who refer to gastroenterology care in Romania: a multicentre study. Eur J Gastroenterol Hepatol. 2004; 16(11):1153-1159. doi: 10.1097/00042737-200411000-00012

[18] Lakatos L, Lakatos PL. Is the incidence and prevalence of inflammatory bowel diseases increasing in Eastern Europe? Postgrad Med J. 2006; 82(967):332-337. doi: 10.1136/pgmj.2005.042416

[19] Kostić M, Djakovic L, Šujić R, Godman B, Janković SM. Inflammatory Bowel Diseases (Crohn´s Disease and Ulcerative Colitis): Cost of Treatment in Serbia and the Implications. Appl Health Econ Health Policy. 2016; 15(1):85-93. doi: 10.1007/s40258-016-0272-z

[20] Goldiș A, Lupușoru R, Gheorghe L, et al. Geographic distribution, phenotype and epidemiological tendency in inflammatory bowel disease patients in Romania. Medicina. 2019; 55(10):704. doi: 10.3390/medicina55100704

[21] Skamnelos A, Katsanos K, Malakos Z, Kolios S, Mitselos I, Politis D, et al. P751 Trends in incidence of inflammatory bowel disease in northwest Greece. J Crohn’s Colitis. 2017; 11(suppl_1):S466-S466. doi: 10.1093/ecco-jcc/jjx002.874

[22] Tozun N, Atug O, Imeryuz N, et al. Clinical characteristics of inflammatory bowel disease in Turkey: a multicenter epidemiologic survey. J Clin Gastroenterol. 2009; 43(1):51-57. doi: 10.1097/MCG.0b013e3181574636

[23] Lakatos L, Kiss LS, David G, et al. Incidence, diseasephenotype at diagnosis, and early disease course in inflammatory bowel diseases in Western Hungary, 2002-2006. Inflamm Bowel Dis. 2011; 17(12):2558-2565. doi: 10.1002/ibd.21607

[24] Vucelić B, Korać B, Sentić M, et al. Epidemiology of Crohn’s Disease in Zagreb, Yugoslavia: A Ten-Year Prospective Study. Int J Epidemiol. 1991; 20(1):216-220. doi: 10.1093/ije/20.1.216

[25] Sincić BM, Vucelić B, Persić M, Brncić N, Erzen DJ, Radaković B, Mićović V, Stimac D. Incidence of inflammatory bowel disease in Primorsko-goranska County, Croatia, 2000-2004: a prospective population-based study. Scand J Gastroenterol. 2006; 41(4):437-444. doi: 10.1080/00365520500320094

[26] Diculescu M, Ciocirlan M, Iacob R, et al. Epidemiology of inflammatory bowel disease in Romania: a nationwide study. Chirurgia. 2011; 106(2):177-183. Available from: https://revistachirurgia.ro/pdfs/2011-2-177.pdf

[27] Kim YR, Jung Y, Kang I, Yeo EJ. Understanding sex differences in autoimmune diseases: immunologic mechanisms. Int J Mol Sci. 2025; 26(15):7101. doi: 10.3390/ijms26157101

[28] Brant SR, Nguyen GC. Is there a gender difference in the prevalence of Crohn’s disease or ulcerative colitis? Inflamm Bowel Dis. 2008; 14:S2-S3. doi: 10.1002/ibd.20540

[29] Carpio D, Barreiro-de Acosta M, Echarri A, Pereira S, Castro J, Ferreiro R, Lorenzo A; EIGA Group (Grupo Gallego de Enfermedad Inflamatoria Intestinal). Influence of urban/ rural and coastal/inland environment on the prevalence, phenotype, and clinical course of inflammatory bowel disease patients from northwest Spain: a cross-sectional study. Eur J Gastroenterol Hepatol. 2015; 27(9):1030-1037. doi: 10.1097/MEG.0000000000000395

[30] Deepak P, Barnes EL, Shaukat A. Health disparities in inflammatory bowel disease care driven by rural versus urban residence: challenges and potential solutions. Clin Gastroenterol Hepatol. 2023; 21(7):1681-1686. doi: 10.1016/j.cgh.2023.04.006

[31] Maté-Jimenez J, Muñoz S, Vicent D, Pajares JM. Incidence and prevalence of ulcerative colitis and Crohn’s disease in urban and rural areas of Spain from 1981 to 1988. J Clin Gastroenterol. 1994; 18(1):27-31. doi: 10.1097/00004836-199401000-00008

[32] Ott C, Obermeier F, Thieler S, Kemptner D, Bauer A, Schölmerich J, Rogler G, Timmer A. The incidence of inflammatory bowel disease in a rural region of southern Germany: a prospective population-based study. Eur J Gastroenterol Hepatol. 2008; 20(9):917-923. doi: 10.1097/MEG.0b013e3282f97b33

[33] Shah SC, Khalili H, Gower-Rousseau C, et al. Sex-based differences in incidence of inflammatory bowel diseases-Pooled analysis of population-based studies from western countries. Gastroenterology. 2018; 155(4):1079-1089.e3. doi: 10.1053/j.gastro.2018.06.043

[34] Zagórowicz E, Walkiewicz D, Kucha P, Perwieniec J, Maluchnik M, Wieszczy P, Reguła J. Epidemiology of inflammatory bowel disease in Poland 2009-2020: nationwide data. Pol Arch Intern Med. 2022; 132(1):161-168. doi: 10.20452/pamw.16162

[35] Binder V. Epidemiology of IBD during the twentieth century: an integrated view. Best Pract Res Clin Gastroenterol. 2004; 18(3):463-479. doi: 10.1016/j.bpg.2003.12.002

[36] Ekbom A. The epidemiology of IBD: a lot of data but little knowledge. How shall we proceed? Inflamm Bowel Dis. 2004; 10(Suppl 1):S32-S34. doi: 10.1097/00054725-200402001-0000