Inflammatory Bowel Disease In Asia Research Articles

Rising Incidence of Inflammatory Bowel Disease in the Asian Subcontinent—An Exploration of Causative Factors

Inflammatory bowel disease (IBD), comprising ulcerative colitis (UC) and Crohn’s disease (CD), is a global health problem with a worldwide increase in incidence. While previously it was more prevalent in Western countries, especially in North America and Europe, there has been a recent sizeable increase in the incidence of IBD in Asia. This article is a brief overview of the causative factors that contribute to this rise in IBD cases in Asian countries. There is a notable disparity between the Asian IBD population and the Western one in terms of age distribution and gender predilection, and genetic studies reveal both shared and unique susceptibility loci. Changes in environmental factors, including alterations in diet, hygiene, and lifestyle, are thought to play a key role in the epidemiological transition observed in Asia. It is crucial to comprehend how genetic predisposition interacts with environmental factors in order to understand the causes of IBD in the Asian population and develop precise interventions to alleviate its impact.

Ten missteps in the management of inflammatory bowel disease in Asia: An expert report by the Asian Pacific Association of Gastroenterology Working Group on Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD) is rapidly emerging in the Asia Pacific region. However, there are many challenges in the diagnosis and management of this condition. The Asian Pacific Association of Gastroenterology (APAGE) Working Group on IBD conducted a round table meeting to identify 10 common mistakes in the management of IBD in Asia. To summarize, many physicians still over rely on a definitive histological diagnosis before starting treatment and do not fully establish disease extent such as perianal and proximal gastrointestinal involvement in Crohn's disease (CD) or extent of involvement in ulcerative colitis (UC). It is also essential to actively look for evidence of extra-intestinal manifestations, which may influence choice of therapy. In terms of conventional therapy, underuse of topical 5 aminosalicylates (5-ASAs) in UC and inappropriate dosing of corticosteroids are also important considerations. Acute severe UC remains a life-threatening condition and delay in starting rescue therapy after inadequate response to intravenous steroids is still common. Anti-tumor necrosis factors should be considered first line in all cases of complex perianal fistulizing CD. Most patients with IBD are on potent immunosuppressive therapy and should be screened for latent infections and offered vaccinations according to guidelines. Under-recognition and management of significant complications such as anemia, osteoporosis, malnutrition, and thromboembolism should also be addressed. Colonoscopy is still not properly performed for dysplasia/cancer surveillance and for evaluating post-op recurrence of CD. Another common misstep is inappropriate withdrawal of medications during pregnancy leading to increased complications for the mother and the newborn.

Evolving Trends and Burden of Inflammatory Bowel Disease in Asia, 1990–2019: A Comprehensive Analysis Based on the Global Burden of Disease Study

BackgroundAsia’s inflammatory bowel disease (IBD) burden has rapidly increased recently, but the epidemiological trends in Asia remain unclear. We report IBD’s incidence, prevalence, mortality, and Disability-Adjusted Life Years (DALY) in 52 Asian countries from 1990 to 2019.MethodsData from the Global Burden of Disease 2019 were analyzed for IBD burden across 52 countries, using metrics like incidence, prevalence, mortality rates, and DALY. The epidemiological trend of IBD from 1990 to 2019 was assessed with the Joinpoint and APC methods. Decomposition and frontier analyses examined factors behind IBD case and death changes. The NORPRED forecasted Asia's morbidity and mortality trends from 2019 to 2044.ResultsFrom 1990 to 2019, The incidence and prevalence of IBD increased in Asia, while mortality and DALY decreased. East Asia had the highest increase in disease burden. IBD incidence was highest among the 30–34 age group, with prevalence peaking in the 45–49 age group. In high-income regions, IBD peak age shifted to younger groups. Decompose analysis showed population growth as the primary factor for the increasing IBD cases in Asia. NORDPRED model predicted a continued IBD burden increase in Asia over the next 25 years.ConclusionsBetween 1990 and 2019, ASIR and ASPR of IBD in Asia increased, while ASMR and ASDR decreased. Due to population growth and aging, the IBD burden is expected to rise over the next 25 years, particularly in East Asia.

Infectious complications in patients with inflammatory bowel disease in Asia: the results of a multinational web-based survey in the 8th Asian Organization for Crohn's and Colitis meeting.

Infectious complications are major concerns when treating patients with inflammatory bowel disease (IBD). This study evaluated clinical differences across countries/regions in the management of infectious diseases in patients with IBD. A multinational online questionnaire survey was administered to participants at the 8th meeting of the Asian Organization for Crohn's and Colitis. The questionnaire included questions regarding surveillance, diagnosis, management, and prevention of infection in patients with IBD. A total of 384 physicians responded to the questionnaire. The majority of Korean (n=70, 63.6%) and Chinese (n=51, 51.5%) physicians preferred vancomycin to metronidazole in the treatment of Clostridium difficile infection, whereas more than half of the Japanese physicians (n=62, 66.7%) preferred metronidazole. Physicians in Korea (n=88, 80.0%) and China (n=46, 46.5%) preferred a 3-month course of isoniazid and rifampin to treat latent tuberculosis infection, whereas most physicians in Japan (n=71, 76.3%) favored a 9-month course of isoniazid. Most Korean physicians (n=89, 80.9%) recommended hepatitis B virus (HBV) vaccination in patients lacking HBV surface antigen, whereas more than half of Japanese physicians (n=53, 57.0%) did not consider vaccination. Differences in the diagnosis, prevention, and management of infections in patients with IBD across countries/regions reflect different prevalence rates of infectious diseases. This survey may broaden understanding of the real-world clinical settings across Asian countries/regions and provide information for establishing practical guidelines to manage patients with IBD.

The epidemiology of inflammatory bowel disease in Asia and Asian immigrants to Western countries

Inflammatory bowel disease (IBD), which comprises Crohn's disease and ulcerative colitis, is an idiopathic inflammatory condition of the gastrointestinal tract. The incidence and prevalence of IBD are rapidly increasing worldwide, particularly in newly industrialized regions such as Asia. Although a large medical armamentarium is available for treating this chronic disease, IBD imposes a marked global disease burden. To understand the complex etiopathogenesis of this condition, it is important to consider the rapidly changing trends in its epidemiology in Asia. During the past few decades, the incidence and prevalence of IBD have significantly increased in both Asian countries and Asian immigrants in Western countries. In this review, we aimed to study and update the epidemiology of IBD in diverse Asian regions and among Asian immigrants in North America and Europe. Moreover, we highlighted that this population exhibits a unique disease phenotype, such as male predominance and high frequency of perianal fistula in Crohn's disease. Also, a different disease phenotype including more complicated disease such as perianal complications was noted in Asian Americans and Asian Europeans.

Update on the epidemiology of inflammatory bowel disease in Asia: where are we now?

Inflammatory bowel disease (IBD) has become a global disease. As IBD is a chronic disease that can result in remarkable morbidity and disability, estimation and understanding the disease burden of IBD is imperative to prepare adequate health care systems. However, variations in IBD incidence or prevalence may reflect differences in the distribution, and there are regional disparities in Asia with a large population of approximately 4.6 billion in 2020, which is equivalent to 60% of the total world population. Although comprehensive understanding of the epidemiology of IBD in Asian countries is difficult, this review includes updated data regarding the incidence and prevalence of IBD and the estimated disease burden in Asia.

Drug therapy and monitoring for inflammatory bowel disease: a multinational questionnaire investigation in Asia.

Background/Aims The incidence and prevalence of inflammatory bowel disease (IBD) is rising in Asia recently. The study aimed to obtain a comprehensive understanding of the current status of drug therapy and monitoring for IBD in Asia.Methods A questionnaire investigation on drug therapy and monitoring for IBD was conducted right before the 6th Annual Meeting of Asian Organization for Crohn’s & Colitis. Questionnaires were provided to Asian physicians to fill out via emails between March and May 2018.Results In total, responses of 166 physicians from 129 medical centers were included for analysis. Among the surveyed regions, the most average number of IBD specialist gastroenterologists and nurses was 4.8 per center in Taiwan and 2.5 per center in Mainland China, respectively. 5-Aminosalicylic acid/sulfasalazine (99.4%) was the most preferred first-line choice for mild-moderate ulcerative colitis (UC), meanwhile corticosteroid (83.7%) was widely applied for severe UC. The first-line medication for Crohn’s disease (CD) markedly varied as corticosteroid (68.1%) was the most favored in Mainland China, Japan, and South Korea, followed by infliximab (52.4%) and azathioprine (47.0%). Step-up strategy was preferred in mild-moderate UC (96.4%), while 51.8% of the physicians selected top-down treatment for CD. Only 25.9% and 17.5% of the physicians could test blood concentration of infliximab and antibody to infliximab in their hospitals, respectively.Conclusions The current status of drug therapy and monitoring for IBD in Asia possesses commonalities as well as differences. Asian recommendations, IBD specialist teams and practice of therapeutic drug monitoring are required to improve IBD management in Asia.

What Are the Different Phenotypes of Inflammatory Bowel Disease in Asia?

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.

Landscape of inflammatory bowel disease in Singapore.

Inflammatory bowel disease (IBD), primarily Crohn’s disease and ulcerative colitis, had been widely recognized to affect the Western population. However, the notable rise in prevalence of IBD in Asia, including Singapore, had garnered much attention to the causal role of the shift in trend, and more importantly, effective and safe management of the conditions of these groups of patients in terms of therapy, healthcare economics as well as patient well-being. This review presents a summary of the current landscape of IBD in Singapore, and discuss on areas that can be explored to improve and better understand the local condition, as prevalence continues to grow.

Incidence and Prevalence Trends of Pediatric Inflammatory Bowel Disease in the Daegu-Kyungpook Province From 2017 to 2020.

Background and Aim: There is paucity of data regarding the epidemiology of pediatric IBD in Asia compared to that of Western countries. We aimed to investigate the incidence and prevalence trends of pediatric inflammatory bowel disease (IBD) in the Daegu-Kyungpook province of South Korea from 2017 to 2020.Methods: This study was a multicenter, retrospective study conducted in eight IBD referral centers located in the Daegu-Kyungpook province. Children and adolescents of ≤18 years who were initially diagnosed with IBD between 2017 and 2020 were included. The annual number of children and adolescents newly diagnosed with IBD and the annual resident population of children and adolescents ≤18 years of age in the Daegu-Kyungpook province were investigated to calculate the annual incidence and prevalence in the region.Results: A total 304 children and adolescents that had been diagnosed with IBD were included in this study. Among these patients, 71.4% had been diagnosed with Crohn's disease (CD), and 28.6% with ulcerative colitis (UC). The population based annual incidences of IBD from 2017 to 2020 were each 7.24, 6.82, 10.27, and 13.33 per 100,000, respectively (P for trend <0.001), 4.48, 5.26, 7.39, and 9.8 per 100,000, respectively, for CD (P for trend <0.001), and 2.76, 1.56, 2.88, and 3.53 per 100,000, respectively, for UC (P for trend = 0.174).Conclusion: Pediatric IBD, especially CD has significantly increased recently in the Daegu-Kyungpook province. Epidemiology studies from other regions of Asia are required to better elucidate this trend of increase in Asia.

The emerging epidemic of inflammatory bowel disease in Asia and Iran by 2035: A modeling study

BackgroundThe projection studies are imperative to satisfy demands for health care systems and proper response to the public health problems such as inflammatory bowel disease (IBD).MethodsTo accomplish this, we established an illness-death model based on available data to project the future prevalence of IBD in Asia, Iran in particular, separately from 2017 to 2035. We applied two deterministic and stochastic approaches.ResultsIn 2035, as compared to 2020, we expected a 2.5-fold rise in prevalence for Iran with 69 thousand cases, a 2.3-fold increment for North Africa and the Middle East with 220 thousand cases, quadrupling of the prevalence for India with 2.2 million cases, a 1.5-fold increase for East Asia region with 4.5 million cases, and a 1.6-fold elevation in prevalence for high‐income Asia‐Pacific and Southeast Asia regions with 183 and 199 thousand cases respectively.ConclusionsOur results showed an emerging epidemic for the prevalence of IBD in Asia regions and/or countries. Hence, we suggest the need for immediate action to control this increasing trend in Asia and Iran. However, we were virtually unable to use information about age groups, gender, and other factors influencing the evolution of IBD in our model due to lack of access to reliable data.

Asian Organization for Crohn's and Colitis and Asia Pacific Association of Gastroenterology practice recommendations for medical management and monitoring of inflammatory bowel disease in Asia.

Inflammatory bowel disease (IBD) has increased in incidence and prevalence in Asian countries since the end of the 20th century. Moreover, differences in the cause, phenotypes, and natural history of IBD between the East and West have been recognized. Therefore, the Asian Organization for Crohn's and Colitis and the Asia Pacific Association of Gastroenterology have established recommendations on medical management of IBD in Asia. Initially, the committee members drafted 40 recommendations, which were then assessed according to Grading of Recommendations Assessment, Development and Evaluation. Eight statements were rejected as this indicated that consensus had not been reached. The recommendations encompass pretreatment evaluation; medical management of active IBD; medical management of IBD in remission; management of IBD during the periconception period and pregnancy; surveillance strategies for colitis-associated cancer; monitoring side effects of thiopurines and methotrexate; and infections in IBD.

Increasing incidence of inflammatory bowel disease in children and adolescents: significance of environmental factors.

Inflammatory bowel disease (IBD) is a chronic relapsing immune-mediated disease of the intestinal tract. Although its prevalence is reportedly lower in Asia than in Western countries, the rapid increase in the incidence of IBD has drawn attention to its etiology, including genetic susceptibility and environmental factors. Specifically, recent studies concerning dietary treatments and intestinal microbiota suggest that these factors may interact with the immune system, and the imbalance of this relationship may lead to immune dysregulation in IBD. Changes in diet or alterations in the composition of the intestinal microbiota may be associated with the increasing incidence of IBD in Asia. Here, we aim to review recent studies on the role of diet and intestinal microbiota in IBD pathogenesis and the results of the investigations performed to modulate these factors.

Characteristics and outcome of primary sclerosing cholangitis associated with inflammatory bowel disease in Asian children

BackgroundCurrent knowledge on the clinical features and natural history of childhood primary sclerosing cholangitis – inflammatory bowel disease in Asia is limited. We described the presenting features and natural history of primary sclerosing cholangitis-inflammatory bowel disease seen in a cohort of Southeast Asian children. MethodsWe conducted a retrospective review of childhood primary sclerosing cholangitis-inflammatory bowel disease from three tertiary centers in Singapore and Malaysia. ResultsOf 24 patients (boys, 58%; median age at diagnosis: 6.3 years) with primary sclerosing cholangitis-inflammatory bowel disease (ulcerative colitis, n = 21; Crohn's disease, n = 1; undifferentiated, n = 2), 63% (n = 15) were diagnosed during follow-up for colitis, and 21% (n = 5) presented with acute or chronic hepatitis, 17% (n = 4) presented simultaneously. Disease phenotype of liver involvement showed 79% had sclerosing cholangitis-autoimmune hepatitis overlap, 54% large duct disease, and 46% small duct disease. All patients received immunosuppression therapy. At final review after a median [±S.D.] duration follow-up of 4.7 [±3.8] years, 12.5% patients had normal liver enzymes, 75% persistent disease, and 12.5% liver failure. The proportion of patients with liver cirrhosis increased from 13% at diagnosis to 29%; 21% had portal hypertension, and 17% had liver dysfunction. One patient required liver transplant. Transplant-free survival was 95%. For colitis, 95% had pancolitis, 27% rectal sparing, and 11% backwash ileitis at initial presentation. At final review, 67% patients had quiescent bowel disease with immunosuppression. One patient who had UC with pancolitis which was diagnosed at 3 years old developed colorectal cancer at 22 years of age. All patients survived. ConclusionsLiver disease in primary sclerosing cholangitis-inflammatory bowel disease in Asian children has variable severity. With immunosuppression, two-thirds of patients have quiescent bowel disease but the majority have persistent cholangitis and progressive liver disease.

The Morphologic Profile of Inflammatory Bowel Disease and the Diagnostic Problem of Crohn’s Disease versus TB Colitis– A Case Series

The aim of this study is to describe the morphologic profile of the biopsy and resection specimen that were diagnosed with Crohn’s disease and ulcerative colitis in the University of the East Ramon Magsaysay Memorial Medical Center (UERMMMC) from 2008-2016. Features that classify the specimen as Inflammatory Bowel Disease – Indeterminate Type are also presented. Considerations for the definitive IBD classification after an initial indeterminate diagnosis by morphology are also briefly discussed. Biopsy and resection specimen that were diagnosed with Crohn’s disease, cannot exclude TB Colitis, are also presented; and the subsequent steps for a definitive classification are also discussed. All the patients included underwent an endoscopic biopsy, and are categorized by histopathologic diagnoses, age, sex, and GIT segment involved in the endoscopic procedure. Patients that underwent subsequent resection due to the disease condition are also identified. Comparison of the histologic findings observed in the patients, with the microscopic basis for the diagnosis recommended by the European consensus on the histopathology of inflammatory bowel disease (2013), and with the histologic features described by Patil et al. (2015) for the inflammatory disorders of the large intestine, is done. The histologic features described by Lamps (2015) for the gastrointestinal TB is used in the evaluation of the findings in the patients diagnosed with Crohn’s disease, cannot exclude TB Colitis. There are 5 Crohn’s disease patients, accounting for 0.8% of all patients with lower GIT inflammatory conditions, and 10 ulcerative colitis patients, accounting for 1.6% of all patients with lower GIT inflammatory conditions. Seven patients, which comprise 1.1% of all patients with lower GIT inflammatory conditions, have the diagnosis of indeterminate colitis. The histologic features of 6 out of 7 patients that had the initial diagnosis of indeterminate colitis presented with morphologic features that favored an ulcerative colitis, but with Crohn’s disease features. In comparison, one patient who had an initial diagnosis of indeterminate colitis presented with morphologic features that favored Crohn’s disease but with ulcerative colitis features. In these patients, correlation with chronology of symptoms and associated ancillary procedures that can classify the patients as CD or UC are recommended to the gastroenterologist attending such patients so that a more definitive classification can be done. Four patients, accounting for 0.6% of all lower GIT inflammatory conditions, were initially diagnosed as Crohn’s disease, cannot exclude TB Colitis. This is in contrast with 34 patients who were diagnosed with diagnosed with Chronic Granulomatous Inflammation, Tuberculosis which accounted for 5.7% of all patients that were diagnosed with inflammatory conditions of the lower GIT. The remaining 536 patients were composed of acute self-limited/infectious colitis, ischemic colitis, eosinophilic colitis, inflammatory polyp, and nonspecific inflammation. With the trend of increasing incidence of Inflammatory Bowel Disease in Asia, comparison of the more commonly seen causes of chronic inflammation of the gastrointestinal tract with a condition that appears to have a growing incidence in the region is necessary for optimal diagnostic protocol, management, and quality of care.

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

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

Treatment of inflammatory bowel disease in Asia: the results of a multinational web-based survey in the 2(nd) Asian Organization of Crohn's and Colitis (AOCC) meeting in Seoul.

Background/AimsInflammatory bowel disease (IBD) management guidelines have been released from Western countries, but no adequate data on the application of these guidelines in Asian countries and no surveys on the treatment of IBD in real practice exist. Since there is a growing need for a customized consensus for IBD treatment in Asian countries, Asian Organization of Crohn's and Colitis performed a multinational survey of medical doctors who treat IBD patients in Asian countries.MethodsA questionnaire was developed between August 2013 and November 2013. It was composed of 4 domains: personal information, IBD diagnosis, IBD treatment, and quality of IBD care. Upon completion of the questionnaire, a web-based survey was conducted between 17 March 2014 and 12 May 2014.ResultsIn total, 353 medical doctors treating IBD from ten Asian countries responded to the survey. This survey data suggested a difference in available medical treatments (budesonide, tacrolimus) among Asian countries. Therapeutic strategies regarding refractory IBD (acute severe ulcerative colitis [UC] refractory to intravenous steroids and refractory Crohn's disease [CD]) and active UC were coincident, however, induction therapies for mild to moderate inflammatory small bowel CD are different among Asian countries.ConclusionsThis survey demonstrated that current therapeutic approaches and clinical management of IBD vary among Asian countries. Based on these results and discussions, we hope that optimal management guidelines for Asian IBD patients will be developed.

Diagnosis of inflammatory bowel disease in Asia: the results of a multinational web-based survey in the 2(nd) Asian Organization for Crohn's and Colitis (AOCC) meeting in Seoul.

Background/AimsAs the number of Asian patients with inflammatory bowel disease (IBD) has increased recently, there is a growing need to improve IBD care in this region. This study is aimed at determining how Asian countries are currently dealing with their IBD patients in terms of diagnosis.MethodsA questionnaire was designed by the organizing committee of Asian Organization for Crohn's and Colitis, for a multinational web-based survey conducted between March 2014 and May 2014.ResultsA total of 353 Asian medical doctors treating IBD patients responded to the survey (114 in China, 88 in Japan, 116 in Korea, and 35 in other Asian countries). Most of the respondents were gastroenterologists working in an academic teaching hospital. While most of the doctors from China, Japan, and Korea use their own national guidelines for IBD diagnosis, those from other Asian countries most commonly adopt the European Crohn's Colitis Organisation's guideline. Japanese doctors seldom adopt the Montreal classification for IBD. The most commonly used activity scoring system for ulcerative colitis is the Mayo score in all countries except China, whereas that for Crohn's disease (CD) is the Crohn's Disease Activity Index. The most available tool for small-bowel evaluation in CD patients differs across countries. Many physicians administer empirical anti-tuberculous medications before the diagnosis of CD.ConclusionsThe results of this survey demonstrate that Asian medical doctors have different diagnostic approaches for IBD. This knowledge would be important in establishing guidelines for improving the care of IBD patients in this region.

Quality of care in inflammatory bowel disease in Asia: the results of a multinational web-based survey in the 2(nd) Asian Organization of Crohn's and Colitis (AOCC) meeting in Seoul.

Background/AimsThe quality of care in inflammatory bowel disease (IBD) has not been systematically estimated. The aim of this study was to investigate the current status of quality of IBD care in Asian countries.MethodsA questionnaire-based survey was conducted between March 2014 and May 2014. The questionnaire was adopted from "An adult inflammatory bowel disease physician performance measure set" developed by the American Gastroenterological Association. If the respondent executed the performance measure in more than 70% of patients, the measure was regarded as well performed.ResultsA total of 353 medical doctors from Asia completed the survey (116 from Korea, 114 from China, 88 from Japan, 17 from Taiwan, 8 from Hong-Kong, 4 from India, 3 from Singapore, and 1 each from the Philippines, Malaysia and Indonesia). The delivery of performance measures, however, varied among countries. The documentation of IBD and tuberculosis screening before anti-tumor necrosis factor therapy were consistently performed well, while pneumococcal immunization and prophylaxis of venous thromboembolisms in hospitalized patients were performed less frequently in all countries. Physician awareness was positively associated with the delivery of performance measures. Variations were also noted in reasons for non-performance or low performance of quality measures, and the two primary reasons cited were consideration of the measure to be unimportant and lack of time.ConclusionsThe delivery of performance measures varies among physicians in Asian countries, and reflects variations in the quality of care among the countries. This variation should be recognized to improve the quality of care in Asian countries.

Changing epidemiological trends of inflammatory bowel disease in Asia.

Inflammatory bowel disease (IBD) has become more common in Asia over the past few decades. The rate of increase in prevalence of the disease varies greatly in Asia, with several countries in East Asia experiencing a more than doubled increase in IBD prevalence over the past decade. Historically, ulcerative colitis (UC) is more common than Crohn's disease (CD) in Asia. However, a reverse trend is beginning to appear in more developed countries in Asia such as Japan, Korea, and Hong Kong. While Asian IBD patients share many similarities with their Western counterparts, there are important differences with significant clinical implications. In Asia, there are more men with CD, more ileo-colonic involvement in CD, less familial aggregation, fewer extra-intestinal manifestations and worse clinical outcomes for older-onset patients with UC. These differences are likely related to the different genetic makeup and environmental exposures in different regions. Evaluation of the differences and rates in epidemiologic trends may help researchers and clinicians estimate disease burden and understand the reasons behind these differences, which may hold the key to unravel the etiology of IBD.