Systematic Reviews
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 7, 2018; 24(25): 2741-2763
Published online Jul 7, 2018. doi: 10.3748/wjg.v24.i25.2741
Current global trends in the incidence of pediatric-onset inflammatory bowel disease
Josef Sýkora, Renáta Pomahačová, Marcela Kreslová, Dominika Cvalínová, Přemysl Štych, Jan Schwarz
Josef Sýkora, Renáta Pomahačová, Marcela Kreslová, Dominika Cvalínová, Jan Schwarz, Division of Gastroenterology, Hepatology and Nutrition, Department of Paediatrics, Charles University in Prague, Faculty of Medicine in Pilsen, Faculty Hospital, Pilsen 304 60, Czech Republic
Přemysl Štych, Department of Applied Geoinformatics and Cartography, Charles University in Prague, Faculty of Science, Prague 128 43, Czech Republic
Author contributions: Sýkora J and Schwarz J contributed equally to this work, and were responsible for the conception, the study design, the integrity of the data and the accuracy of the data analysis and performed the data acquisition; Pomahačová R, Kreslová M, Cvalínová D and Štych P analyzed the data, drafted the manuscript and revised it critically for important intelectuall content; Štych P performed and edited choropleth maps; Sýkora J and Schwarz J wrote the manuscript; all authors have seen and approved the version of manuscript to be submitted.
Supported by the “On Our Own Feet Movement - Přátelé stonožky” - Endowment Program; and Research Project Progress Q-39.
Conflict-of-interest statement: The authors have no conflicts of interest to disclose.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Jan Schwarz, MD, Assistant Professor, Division of Gastroenterology, Hepatology and Nutrition, Department of Paediatrics, Charles University in Prague, Faculty of Medicine in Pilsen, Faculty Hospital, Alej Svobody 80, Pilsen 304 60, Czech Republic. schwarzj@fnplzen.cz
Telephone: +420-377-104330 Fax: +420-377-104693
Received: March 29, 2018
Peer-review started: March 29, 2018
First decision: May 9, 2018
Revised: June 1, 2018
Accepted: June 25, 2018
Article in press: June 25, 2018
Published online: July 7, 2018
Processing time: 97 Days and 13 Hours
Abstract
AIM

To perform a comprehensive review and provide an up-to-date synopsis of the incidence and trends of inflammatory bowel disease (IBD).

METHODS

We systematically searched the MEDLINE (source PubMed), EMBASE and Cochrane Library databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (period: 1985-2018) to identify studies reporting population-based data on the incidence of pediatric-onset (< 19 years at diagnosis) IBD in full manuscripts. Two authors carried out screening and data extraction. Choropleth interactive maps and temporal trends were used to illustrate the international differences and incidences of and changes in IBD and subtypes.

RESULTS

In total, one hundred forty studies reporting data from 38 countries were considered in this review. The highest annual pediatric incidences of IBD were 23/100000 person-years in Europe, 15.2/100000 in North America, and 11.4/100000 in Asia/the Middle East and Oceania. The highest annual incidences of Crohn’s disease (CD) were 13.9/100000 in North America and 12.3/100000 in Europe. The highest annual incidences of ulcerative colitis (UC) were 15.0/100000 in Europe and 10.6/100000 in North America. The highest annual incidences of IBD-unclassified (IBD-U) were 3.6/100000 in Europe and 2.1/100000 in North America. In the time-trend analyses, 67% of CD, 46% of UC and 11% of IBD-U studies reported an increasing incidence (P < 0.05). The risk of IBD is increasing among first-generation of migrant populations.

CONCLUSION

Globally, the incidence of IBD varies greatly by geographical areas. The steadily increasing incidence of pediatric IBD over time indicates its emergence as a global disease, suggesting that studies should investigate the environmental risk factors among pediatric cohorts.

Keywords: Children; Incidence; Inflammatory bowel disease; Crohn’s disease; Ulcerative colitis; Inflammatory bowel disease-unclassified

Core tip: The incidence of inflammatory bowel disease (IBD) is unclear in the pediatric literature. We comprehensively reviewed and critically evaluated population-based and national cohort studies investigating the incidence of IBD and its global trends. One hundred forty studies met the inclusion criteria. The incidence of pediatric-onset IBD has been steadily increasing over time in different geographical areas in both developed and developing regions worldwide, whereas those in the West may have reached a plateau. This indicates the emergence of an IBD epidemic; however, incidence data from developing regions are limited. Exploring the changes and increasing incidence of pediatric IBD may provide new insights into the potential etiology of IBD.