East Meets West: The Increasing Incidence of Inflammatory Bowel Disease in Asia as a Paradigm for Environmental Effects on the Pathogenesis of Immune-Mediated Disease

The burden of inflammatory bowel disease (IBD) in Asia has been increasing over the past decades. Although patients with IBD show heterogenous phenotypes depending on the individual characteristics, no significant differences have been established in the IBD phenotypes of Western and Asian populations. However, despite the much lower incidence of IBD in Asia than in Western countries, the incidence has been rapidly increasing in Asia while remaining stable in Western countries. The incidence of ulcerative colitis (UC) showed an earlier and a more marked increase than the incidence of Crohn disease (CD), but the UC-to-CD ratio has recently decreased because of a relative increase in the incidence of CD in Asia. While CD shows a significant male predominance, UC only shows a slight male predominance. A recent study reported that the incidence of IBD in Asia showed a bimodal age distribution with increasing IBD prevalence, similar to the findings of Western studies. CD in Asian patients, especially those in East Asia, is characterized by ileocolonic involvement and perianal fistula. The frequency of extraintestinal manifestations, including primary sclerosing cholangitis, appears to be lower in Asia, but this finding should be interpreted with caution due to the transient and nonspecific nature of these manifestations. Although familial aggregation is lower in East Asia, it may also be explained by the low prevalence of IBD in Asia. Thus, more studies should focus on the differences in phenotypes in Asian IBD patients versus Western patients.

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Does Consuming the Recommend Daily Level of Fiber Prevent Crohn's Disease?

A rising trend in the incidence and prevalence of inflammatory bowel disease (IBD) in Asia has been recognized for the past two decades. It has been postulated that this phenomenon may be related to the westernization of lifestyles, including changes in dietary habits and environmental changes such as improved sanitation and industrialization. Previously we reported that the incidence and prevalence rates of IBD in Asia were low compared with the West, but there was a notably rising secular trend. In this review, we summarize the recent epidemiological data in Asia, characterize the clinical features, risk factors and genetic susceptibility of Asian IBD patients, and compare these to those of Western IBD patients. In the past decade, the incidence and prevalence of IBD reported across Asia, particularly in East Asia, has continued to increase. Familial clustering is generally uncommon in East Asia but appears to be higher in West Asia. The genetic susceptibilities in Asian IBD patients differ from those of White patients, as NOD2/CARD15 mutations are much less common. The clinical phenotypes and complication rates of Asian IBD resemble the White population in general, but with some differences, including lower surgical rates, higher prevalence of males, and higher prevalence of ileocolonic involvement among East Asian Crohn's disease patients, and a low frequency of primary sclerosing cholangitis among IBD patients in East and Southeast Asia.

Beyond Gene Discovery in Inflammatory Bowel Disease: The Emerging Role of Epigenetics

Inflammatory bowel disease in children and adolescents: Working Group Report of the First World Congress of Pediatric Gastroenterology, Hepatology, and Nutrition.

Background The incidence of inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), is increasing internationally, particularly in developing nations where rates were historically low. Previous reports of the incidence and prevalence of pediatric-onset IBD have identified a paucity of population-based studies. Aims We reviewed the global trends in incidence of pediatric IBD using evidence from population-based studies. Methods (PROSPERO CRD42019125193) We systematically reviewed studies indexed in MEDLINE, EMBASE, Airiti Library, and SciELO from 01/2010-02/2020 to identify population-based studies reporting the incidence of pediatric-onset IBD, CD, and UC. Included studies combined childhood and adolescent-onset IBD (onset <21y). Changes in incidence since 2000 were plotted by continent, with data from 2000–09 provided by our previous systematic review1. To depict trends, multiple times points reported in single studies were connected on graphs. When incidence was reported as an aggregated estimate over a range of years, data was plotted using the midpoint of the interval. Results Of 8096 abstracts screened, 74 studies described the incidence of IBD, CD, or UC in 33 countries (Figure panel A). The incidence of pediatric-onset IBD is highest in Northern Europe and North America, and lowest in Southern Europe, Asia, and the Middle East. This geographical distribution is similar in UC, while incidence of pediatric-onset CD is highest in North America and Northern Europe, followed by Australia. Trends in incidence over time, stratified by continent, are reported in Figure, panel B. Significantly increasing incidence of IBD, CD, and/or UC was reported in China, Bahrain, Canada, New Zealand, Australia, Singapore, Saudi Arabia, and most European countries. Very Early Onset (VEO) IBD significantly increased in Canada, however Saudi Arabia reported decreasing incidence of VEO-CD but stable incidence of VEO-UC. Conclusions Conclusion: Incidence of pediatric-onset IBD are highest in Northern Europe and North American and are increasing globally. There remains a paucity of studies from many parts of the world on the incidence pediatric IBD. Further research is needed to understand the pathogenesis of the rising incidence of pediatric IBD, including work to understand the genetic, environmental, immunological and microbiome alterations leading to the increasing rates in children.

BackgroundCountries have different diagnostic procedures and treatment regimens for inflammatory bowel disease (IBD) patients. In addition to differences in population characteristics, completeness of data and health registries, different follow-up time and case definitions can have a large impact on estimates of the incidence and prevalence of IBD.AimThe aim of this study was to use hospital and prescription data to estimate incidence and prevalence of Crohn’s disease (CD) and ulcerative colitis (UC), using different case definitions.MethodsThis study used nationwide data from the Norwegian Patient Registry (2008 to 2017) and the Norwegian Prescription Database (2004 to April 2018). Incidence and prevalence were estimated using different case definitions of an IBD patient, varying the number of IBD-related hospital visits and IBD prescriptions required. The base case definition included patients with at least one IBD hospital visit and two IBD prescriptions or two IBD hospital visits.ResultsFrom 2010 to 2017, 16,758 incident IBD patients fulfilled our base case definition, with 6045 diagnosed with CD (36.1%) and 10,713 (63.9%) with UC. For CD, 47.2% of the patients were male while 53.8% of UC patients were male. The base case incidence varied between 14.1 and 16.0 per 100,000 person-years for CD and 24.7 and 28.4/100,000 person-years for UC patients in the years 2010–2017. When we required at least two IBD hospital visits, not utilizing the prescription data, the CD incidence was 22.3 per 100,000 person-years in 2010 and 13.9 per 100,000 person-years in 2017. For UC, the incidence was 47.4 and 20.6 per 100,000 person-years in 2010 and 2017. In 2017, the prevalence of CD was 0.27% (95% CI: 0.26–0.27) and 0.50% (95% CI: 0.490–0.502) for UC.ConclusionAccording to our base case definition, the incidence of IBD in Norway was stable from 2010 to 2017. Both the incidence and prevalence of IBD in Norway is among the highest in the world. Moreover, the study also highlights the consequences of different case definitions.

A Genomewide Analysis Provides Evidence for Novel Linkages in Inflammatory Bowel Disease in a Large European Cohort

Inflammatory bowel disease (IBD) has traditionally beenconsidered a Western disease. However, the last 2 decadeshave seen an increase in the reports of both ulcerative colitis(UC) and Crohn’s disease (CD) from Asian countries [1].Most of these reported series have been hospital-based withonly one population-based survey by Sood et al. [ 2]. Time-trend data from Japan and China indicate a dramatic increasein the incidence of UC and a more gradual increase in that ofCD [1]. In addition, a higher incidence of UC has been notedamongst second-generation Asian migrants in the UnitedKingdom [3]. This increase in the incidence and prevalenceof IBD in Asia mirrors the epidemiological trend in theWestern world that occurred 50 years ago Though increasedawareness of IBD, better diagnostic facilities, and the growthof the specialty appear to have played a major factor for thisincrease in reported incidence, there is probably also agenuine increase in the incidence of both UC and CD [1].The role of the changing environment in the pathogen-esis of IBD is likely to be a major contributory factor forthe increase in this condition in Asian countries. Improve-ment in sanitation and public health, while inevitablyleading to a decrease in the burden of infectious diseases,have been shown to be associated with an increase inautoimmune and chronic inflammatory diseases [4]. Theenvironmentalfactorswhicharewell-recognisedasassociatedwith IBD include smoking, diet, stress, microbial agents,appendicectomy, social status and intestinal permeability tofermentable oligo-, di- and mono-saccharides and polyols(FODMAPs).In this issue of the Journal, Pugazhendhi et al. [5]fromatertiary referral hospital in southern India report a case–control study that looked at the association of surrogatemarkers of environmental hygiene in patients with CDcompared to age-linked healthy controls. They found thaturban residence, safe drinking water and availability of pipedwater (all indicators of better hygiene) were positivelyassociated with CD whereas consumption of fish (a sourceof ω-3 polyunsaturated fatty acids) and exposure to cattle (anindicator of poor hygiene) were negatively associated withCD. The message of the study is clear—improved hygienewas associated with a higher prevalence of CD in this area.The ‘hygiene hypothesis’ [6] of IBD is based on theobservation that incidence of IBD has increased in bothdeveloping and developed countries with improvements inhygiene during the 20th century. It claims that raisingchildren in extremely hygienic environments negativelyaffects immune development and tolerance to a variety ofantigenic challenges, which in later life predisposes them todevelop chronic inflammatory diseases such as IBD.However, the evidence for the contribution of severalfactors included in this hypothesis has never been analyzedin a systematic manner. In the present study too, except fordiet (fish oil), all the other factors found to be correlatedwith the development of CD, can be linked to gutmicrobiota and immune tolerance.The mucosal surface of the human gastrointestinal tractis approximately 200–300 m

Background/Aims: The incidence of pediatric inflammatory bowel disease (IBD) in Western countries is on the rise. No prospective studies have been conducted on the epidemiology of pediatric IBD in Poland. The aim of the study was to define the characteristics of new pediatric IBD and assess the incidence of new IBD among children in Poland between 2002 and 2004. Methods: Patient records from 24 pediatric gastroenterology centers servicing the whole population of Poland were collected. IBD diagnosis was based on clinical, radiological, endoscopic and histological features. Results: There were 491 new IBD patients, representing an overall incidence of IBD of 2.7 cases/100,000 children/year. The incidence of Crohn’s disease (CD) was 0.6, ulcerative colitis (UC) 1.3, and indeterminate colitis (IC) 0.8. The age-related incidence of IBD was 1.8 in the 0- to 10-year-old age group, rising to 3.7 for the 11- to 18-year age group. Conclusions: The overall incidence of IBD (as well as CD, UC and IC) in Poland is lower than that in Western countries. The relative contribution of UC and IC to the overall IBD incidence is higher in Poland than in most Western countries. These findings may suggest a tendency towards under- or misdiagnosis.

Introduction The incidence of early-onset inflammatory bowel disease (IBD) is high in Europe and North America with numbers rising in recent decades. An accurate indication of the current incidence and temporal trends experienced by a whole population is useful in understanding possible aetiological factors and is essential for the planning of future specialist healthcare provision. Methods This study reports the incidence of early-onset IBD within the Scottish population over a 6-year period (2003–2008), comparing the incidence and demographic attributes to previous figures. Three paediatric gastroenterology networks provide care for all paediatric IBD patients in Scotland. Retrospective data regarding incident cases of IBD diagnosed <16 years old were collected using a centrally coordinated database. Duplicates and diagnoses outwith Scotland were excluded. General Register Office for Scotland population statistics were used to calculate incidence. Statistical comparisons were made by Mann–Whitney U test. Results During the study period 430 patients <16 years were diagnosed with IBD in Scotland giving an overall incidence of 7.7/100 000/year. The incidence of Crohn's disease (CD) was 4.7/100 000/year, ulcerative colitis (UC) 2.0/100 000/year and inflammatory bowel disease unspecified (IBDU) 1.0/100 000/year. When compared with previous data from 1990 to 1995, significant rises in the incidence of IBD from 4.4/100 000/year (p=0.002) and CD from 2.8/100 000/year (p=0.002) were seen. The rise in UC from 1.6/100 000/year was not significant (p=0.13). The median age at diagnosis between 2003 and 2008 was 11.8 years for IBD and UC, and 11.9 years for CD. When compared with 1990–1995 data, there was a significant decrease in the age at diagnosis of CD from 12.8 years (p=0.009), but not in UC from 12.3 years (p=0.49). The male to female ratio was 1.5:1 for CD and 1.1:1 for UC during 2003–2008 compared to 1.2:1 for CD and 0.9:1 for UC between 1990 and 1995. Conclusion The number of Scottish children diagnosed with IBD continues to rise with the rates of IBD and CD rising significantly by 70% and 61%, respectively. Although UC has risen by 25%, this was not significant. This continuing rise has clear implications for the health of Scotland's children and the local provision of specialist healthcare. A greater understanding of the changing demographic of early-onset IBD may give us clues as to the aetiology of this chronic condition and aid future disease prevention measures.

Many of the patients with inflammatory bowel disease (IBD) are children and adolescents, and the incidence of pediatric IBD is increasing. However, understanding epidemiological trends is crucial for effective prevention and treatment and reducing the local and global burden of IBD. Little data exist regarding the incidence of IBD in the child population in the Kujawsko-Pomorskie Voivodeship. The aims of this study were to evaluate the incidence of IBD in the period 2011 - 2022 and to compare the data regarding three types of IBD, namely ulcerative colitis (UC), Crohn's disease (CD), and unclassified inflammatory bowel disease (IBD-U), from the first half, i.e. 2011 - 2016, to the second half, i.e. 2017 - 2022. This retrospective study analyzed the medical records of 118 IBD patients hospitalized at the Department of Pediatrics, Allergology and Gastroenterology from the central-northern part of Poland. Of the 118 patients diagnosed with IBD, 48 (40.68%) had CD, 57 (48.31%) had UC, and 13 (11.01%) had IBD-U. Between 2011 and 2016, 48 new IBD patients were diagnosed, with a further 70 new cases added between 2017 and 2022, representing a significant increase over the period (P = 0.033). Also, a significant increase was seen for UC, i.e. rising from 19 new cases between 2011 and 2016, to 38 between 2017 and 2022 (P = 0.015). The increase in CD was not significant. The incidence of pediatric IBD in the central-northern district of Poland is lower than other countries, it nonetheless appears to be increasing, particularly in children with UC. The number of IBD diagnoses in children has increased by nearly 50% over the last 6 years.

P104 THE INCIDENCE OF INFLAMMATORY BOWEL DISEASE: ANALYZING HISTORICAL TRENDS TO PREDICT THE FUTURE

Worldwide incidence and prevalence of inflammatory bowel disease in the 21st century: a systematic review of population-based studies