Population Density and Risk of Inflammatory Bowel Disease: A Prospective Population-Based Study in 13 Countries or Regions in Asia-Pacific

Is the rise in Crohn's disease in India accompanied by a fall in intestinal tuberculosis? A single-center experience

INTRODUCTION

The relationship between the incidence of intestinal tuberculosis (TB) and Crohn's disease (CD) is interesting, especially considering the striking similarity between the two conditions. Some studies from Asian populations suggested that the incidence of intestinal TB decreases when there is an increase in CD.

AIM

To compare the incidence trend between intestinal TB and CD over 15 years.

METHODS

Medical records of patients seen in the Division of Gastroenterology over 15 years (2005-2019) were reviewed. CD was diagnosed according to the Copenhagen criteria. Intestinal TB was diagnosed in the appropriate clinical situation if any one or more of the following was present: (1) positive TB MGIT culture; (2) positive Gene Xpert for TB; (3) suggestive histologic findings, with positive tissue acid-fast bacillus (AFB) on smear or with sustained response to anti-TB therapy. The incidence time trend of patients with CD and intestinal TB diagnosis was then studied year-wise.

RESULTS

632 medical case records were accessed; 60 patients were excluded due to inadequate data or not fulfilling diagnostic criteria. The 572 patients included 224 with intestinal TB (median age 37 years, IQR 22; 125 [56%] females) and 348 with CD (median age 40 years, IQR 25; 159 [46%] females [p < 0.02 as compared to TB]). Thus, more patients with CD were seen during the study period, but there was no correlation between the incidence of the two conditions (r = 0.318; p = 0.25).

CONCLUSION

In Indian patients in a single private-sector center, there was no inverse correlation between the incidence of intestinal TB and CD over 15 years.

Temporal trend in the natural history of ulcerative colitis in a country with a low incidence of ulcerative colitis from 2000 through 2018

Background/Aims

The incidence of ulcerative colitis (UC) in Thailand (crude incidence rate of 0.28 per 100,000 persons) is much lower than in the West. The burden of UC varies in different populations. The aim of this study was to evaluate the natural history of UC over the two decades in Bangkok, Thailand.

Methods

This retrospective study included patients who were diagnosed with UC between 2000 and 2018 in 2 university hospitals. To evaluate changes in the disease course, we stratified patients into 2000–2009 cohort and 2010–2018 cohort. The cumulative probability of endoscopic healing, UC-related hospitalization and colectomy was estimated using the Kaplan-Meier method.

Results

A total of 291 UC patients were followed for total of 2,228 person-years. Comparison between 2 cohorts, there were no differences in disease pattern and severity whereas an increase in the combination use of oral and topical mesalamine and the early use of thiopurine was observed. Only 1% of patients for each cohort required biologic agent at 5 years. The rate of achieving mucosal healing increased from 15% to 46% at 3 years (P<0.01). The rate of UC-related hospitalization decreased from 30% to 21% at 5 years (P<0.05). The rate of colectomy decreased from 6% to 2% at 5 years (P<0.05).

Conclusions

The natural history of UC in a low incidence country was less aggressive than the West. Over the past two decades, the rates of UC-related hospitalization and colectomy have been decreasing which were similar to the West.

High initial bowel resection rate and very-early-onset inflammatory bowel disease - A challenge in a low-prevalence area

BACKGROUND

Inflammatory bowel diseases (IBD) include ulcerative colitis (UC) and Crohn's disease (CD). The incidence in children and adolescents has risen since the 21st century globally, including Taiwan. The study aimed to disclose the characteristics and outcome of pediatric IBD (pIBD) patients in a tertiary center for the past two decades.

METHODS

We retrospectively reviewed the charts of pIBD children from 2000 to 2018 in a tertiary center in Northern Taiwan. Demographics, presentations, diagnostic modalities, treatment, and outcomes were analyzed.

RESULTS

A total of 38 cases were enrolled, including 27 CD and 11 UC patients. An almost 3-folds increase in incidence after 2010 was observed. Twelve cases (32%) were early-onset, and six of them (16%) were very-early-onset; four of them were detected with single-gene mutations [XIAP, TTC7A (2 siblings), and ZAP70]. Eleven CD patients (40.7%) received bowel resection at the onset, and another two (7.4%) had bowel resection years after the diagnosis. Initial bowel resection was associated with fibrostenotic/penetrating behavior, early-onset disease, and growth failure.

CONCLUSION

This study demonstrated an increased incidence of pIBD in the past two decades in Taiwan, a low-prevalence region. The initial high bowel resection rate in CD was related to the fibrostenotic and/or penetrating behavior, younger age at diagnosis, and growth failure.

Inflammatory bowel disease in India: challenges and opportunities

Evidence is emerging that inflammatory bowel diseases (IBDs) are becoming increasingly prevalent in developing countries, altering the previously held view that these were diseases of the West. Within this is a substantial increase in the burden of this disease in India, a matter of great importance to the country itself as well as in furthering our understanding of the disease. There is comparatively less data on this, both from the epidemiological standpoint as well as on disease pathogenesis in this particular cohort and is very much a subject matter of evolving understanding and research. This article aims to look at the changing global distribution of the disease and its implications. The Indian disease phenotype, and the aetiology of disease development will also be addressed with particular focus on differing pathogenetic processes in the Indian subpopulation, with consideration of what clues may be offered by the increasing incidence of the disease in this developing nation. Available evidence will be evaluated with the objective of providing a comprehensive overview of the development of IBD in India.

Changing Patterns of Relationships Between Geographic Markers and IBD: Possible Intrusion of Obesity

Background

Latitude and lactase digestion status influence incidence and prevalence rates of some noncommunicable diseases. Latitudinal correlations helped define beneficial roles of vitamin D in many diseases like inflammatory bowel disease (IBD). In view of recent global expansion of IBD and population migrations, we reexamine relations with these markers. As these changes also paralleled the pandemic of obesity, we explore possible interactions with IBD.

Methods

We undertook a literature review to compare rates of obesity, Crohn's disease and ulcerative colitis with the geographic markers of lactase digestion status, average population-weighted national latitude, and national yearly sunshine exposure. Pearson correlations were used throughout to determine r correlation factors. Statistical significance was accepted at P <0.05 using 2-tailed tests.

Results

Forty-seven countries were matched with various data sets that could be analyzed (range of availability was 49%-85%). While global correlations of IBD with latitude and lactase status remain similar to previous analyses, in Europe and Asia, outcomes were different. Global outcome contains a statistical paradox related to combining countries from Europe and Asia. Obesity showed moderate global correlations with IBD but weak and negligible correlations in Europe and Asia. There was also a weak global correlation with latitude.

Conclusions

It is suggested that global correlations point to parallel geographic spread of IBD and obesity. The lack of latitudinal relations with obesity suggests reduced vitamin D effect. The paradox supports epidemiological differences in western and eastern IBD. Obesity combined with IBD may contribute to different relations, partly due to variable vitamin D effects.

Microbiome characterization and re-design by biologic agents for inflammatory bowel disease insights

The therapeutic effect of inflammatory bowel disease has improved in the past decades, but most of patients cannot tolerate, do not respond to drugs, or relapse after treating with conventional therapy. Therefore, new and more effective treatment methods are still needed in treatment of IBD. In this review, we will discuss the relevant mechanisms and the latest research progress of biologics (anti-TNF treatments, interleukin inhibitors, integrin inhibitors, antisense oligonucleotide, and JAK inhibitors) for IBD, focus on the efficacy and safety of drugs for moderate-to-severe IBD, and summarize the clinical status and future development direction of biologics in IBD.

Nigeria and Italy Divergences in Coronavirus Experience: Impact of Population Density

Background

The reports and information on coronavirus are not conspicuously emphasising the possible impact of population density on the explanation of difference in rapid spread and fatality due to the disease and not much has been done on bicountry comparisons.

Objective

The study examined the impact of population density on the spread of COVID-19 pandemic in two sociodemographic divergent countries.

Methods

The study conducted a scoping review of published and unpublished articles including blogs on incidences and fatalities of COVID-19. The analysis followed qualitative description and quantitative presentation of the findings using only frequency distribution, percentages, and graphs.

Results

The two countries shared similar experience of "importation" of COVID-19, but while different states ordered partial lockdown in Nigeria, it was an immediate total lockdown in Italy. The physician/patient ratio is high in Italy (1 : 328) but low in Nigeria (1 : 2500), while population density is 221 in Nigeria and 206 in Italy. Daily change in incidence rate reduced to below 20% after 51 and 30 days of COVID-19 first incidence in Italy and Nigeria, respectively. Fatality rate has plummeted to below 10% after the 66^th day in Italy but has not been stabilised in Nigeria.

Conclusion

The authors upheld both governments' recommending measures that tilted towards personal hand-hygienic practices and social distancing. Authors suggested that if Italy with its high physician/patient ratio and lower population density compared to Nigeria could suffer high fatality from COVID-19 pandemic under four weeks, then Nigeria with its low physician/patient ratio and higher population density should prepare to face harder time if the pandemic persists.

Changing Global Epidemiology of Inflammatory Bowel Diseases: Sustaining Health Care Delivery Into the 21st Century

Crohn's disease and ulcerative colitis have emerged as global diseases. They affect over 2 million individuals in the North America, 3.2 million in Europe, and millions more worldwide. The recent decades have been characterized by several important changes in the epidemiology of these diseases, in particularly an increasing incidence rates in newly industrialized countries experiencing a westernization of lifestyle. While rates of surgery have experienced a temporal decline attributable in part to increasing availability of medical treatments, earlier initiation of effective therapy, and changes in clinical practice, the healthcare costs associated with these diseases have continued to increase, in part due to costly therapies. Robust epidemiologic and experimental studies have defined the role of the external environment and microbiome on disease pathogenesis and have offered opportunities for disease prevention by modifying such factors. We propose several important steps that are necessary to provide globally sustainable inflammatory bowel disease care in the 21st century.

Patients' Preference of Topical Therapy for Ulcerative Colitis in Japan: A Web-based 3T Survey

Background

The therapeutic drugs available for ulcerative colitis (UC) have recently increased. However, use of topical therapy for UC in Japan has not been determined. This study aimed to investigate real-world use of topical therapy for UC in Japan using a web-based survey designed for UC patients.

Methods

A web-based questionnaire on UC management was administered to 773 patients over a 2-day period in September 2019. The responses regarding topical therapy use were analyzed.

Results

Questionnaire responses were obtained from 323 UC patients. Of these, the mean disease duration was 12.2 years, and 220 patients (68.1%) had used topical therapy, of whom 68 (21.1%) were currently using this treatment. The frequency of using the prescribed topical therapy was appropriate in 36.8% of patients, only when needed in 38.6%, and rarely in 24.5%. Among all topical therapy users, 64.4% reported that budesonide foam was easy to use, which was significantly higher than the rates for mesalazine suppositories (43.6%), mesalazine enemas (12.9%), and glucocorticoid enemas (13.9%; P < 0.05). Regarding treatment effects, 68.9% of patients were satisfied with the budesonide foam, which was a significantly higher rate of satisfaction than those for mesalazine suppositories (44.6%), mesalazine enemas (30.2%), glucocorticoid enemas (36.1%), and glucocorticoid suppositories (41.9%; P < 0.05).

Conclusions

Although topical therapy use was common in this Japanese UC population, patient adherence was not very high. Of all the topical therapy types, budesonide foam, which has recently become available, was rated highly by these patients.

Environmental, Nutritional, and Socioeconomic Determinants of IBD Incidence: A Global Ecological Study

BACKGROUND AND AIMS

The wide variation in inflammatory bowel disease [IBD] incidence across countries entails an opportunity to recognise global disease determinants and hypothesise preventive policies.

METHODS

We fitted multivariable models to identify putative environmental, nutritional, and socioeconomic determinants associated with the incidence of IBD (i.e. ulcerative colitis [UC] and Crohn's disease [CD]). We used the latest available country-specific incidence rates, and aggregate data for 20 determinants, from over 50 countries accounting for more than half of the global population. We presented the associations with exponentiated beta coefficients (exp[β]) indicating the relative increase of disease incidence per unit increase in the predictor variables.

RESULTS

Country-specific incidence estimates demonstrate wide variability across the world, with a median of 4.8 new UC cases (interquartile range [IQR] 2.4-9.3), and 3.5 new CD cases [IQR 0.8-5.7] per 100 000 population per year. Latitude (exp[β] 1.05, 95% confidence interval [CI] 1.04‒1.06, per degree increase), prevalence of obesity [1.05, 1.02‒1.07, per 1% increase], and of tobacco smoking [0.97, 0.95‒0.99, per 1% increase] explained 71.5% of UC incidence variation across countries in the adjusted analysis. The model for CD included latitude [1.04, 1.02‒1.06], expenditure for health (1.03, 1.01‒1.05, per 100 purchasing power parity [PPP]/year per capita increase), and physical inactivity prevalence [1.03, 1.00‒1.06, per 1% increase], explaining 58.3% of incidence variation across countries. Besides expenditure for health, these associations were consistent in low/middle- and high-income countries.

CONCLUSIONS

Our analysis highlights factors able to explain a substantial portion of incidence variation across countries. Further high-quality research is warranted to develop global strategies for IBD prevention.

The epidemiology of inflammatory bowel disease: East meets west

The incidence of inflammatory bowel diseases (IBD) in East has risen over the past decade to become a global disease. The increasing number of studies on the incidence and course of IBD in East has enabled us to explore East versus West differences in the epidemiology of IBD which could enhance our understanding of the heterogeneity of the disease and eventually assist in the discovery of novel therapeutic targets and design of preventive strategies. Comparison of population-based data in East and West reveals that the incidence of IBD has risen rapidly in East while plateauing in West. Furthermore, the clinical presentation and course of IBD differs between East and West with more patients in East presenting with complicated disease. Considering the scarcity of population-based data from East and the lack of studies with long durations of follow-up, it remains to be clarified whether these differences reflect true differences in disease presentation. The effects of genetic and environmental risk factors contributing to IBD also differ between Eastern and Western populations. Considering the differential effects of genetic and environmental risk factors in East and West, future studies should seek to discover novel genetic and environmental risk factors which might specifically apply to eastern populations. In this narrative review, we compare the epidemiology of IBD between eastern and western countries by summarizing evidence from population-based cohort studies in the last ten years. Furthermore, we look at differences in genetic susceptibility and environmental triggers of IBD between East and West.

Fresh Saengshik Showed a Positive Effect on Mitigating Dextran Sulfate Sodium-Induced Experimental Colitis in Mice

This study was to compare the anticolitis activity of fresh Saengshik (FSS) with heated Saengshik (HSS) with dextran sulfate sodium (DSS)-induced experimental colitis mouse model. Both FSS- and HSS-fed colitis mice exhibited the effects of the increase in the body weight, the alleviation in the colon shortening, and the reduction of the ratio of colon weight to length. However, FSS-fed colitis mice showed a much more significant decrease in DSS-induced tissue damage by mucosal edema and crypt deficiency than did HSS-fed ones. Besides, FSS contributed to decreasing the serum levels of proinflammatory cytokines (tumor necrosis factor-alpha and interleukin-1 beta) and inhibiting the colonic mRNA expressions of these cytokines in colitis tissue of the mice. FSS also resulted in the lower colonic mRNA expression level of inflammation-related inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in colitis mice than did HSS. Overall results confirmed Saengshik, especially FSS, inhibits more effectively against DSS-induced inflammation reaction in colitis mice than HSS.

Protective Effect of Cicer arietinum L. (Chickpea) Ethanol Extract in the Dextran Sulfate Sodium-Induced Mouse Model of Ulcerative Colitis

Inflammatory bowel disease (IBD) is a major risk factor of colorectal cancer. Drugs currently used for IBD exhibit adverse effects including vomiting, nausea, and diarrhea. Naturally derived novel alternative therapies are required to overcome these limitations. In this study, we investigated the protective effects of ethanol extract of Cicer arietinum (CEE) in a dextran sodium sulfate (DSS)-induced mouse model of colitis. CEE markedly improved DSS-induced clinical symptoms and histological status, such as the disease activity index, spleen weight, and colon length. Moreover, CEE-treated mice showed significant recovery of DSS-induced crypt damage and cell death. CEE suppressed myeloperoxidase (MPO) activity and macrophage marker F4/80 mRNA expression in colonic tissue of mice with DSS-induced colitis, indicating neutrophil infiltration and macrophage accumulation, respectively. Although DSS upregulated pro-inflammatory mediators and activated transcription factors, CEE downregulated the mRNA expression of cytokines including interleukin-6, interleukin-1β, and tumor necrosis factor-α, protein expression of cyclooxygenase-2 and inducible nitric oxide synthase, as well as activation of nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3). Hence, our findings reveal that the anti-inflammatory properties of CEE, involving the downregulation of the expression of pro-inflammatory mediators by inactivating NF-κB and STAT3 in DSS-induced colitis mice.

Viewpoint: Inflammatory Bowel Diseases Among Immigrants From Low- to High-Incidence Countries: Opportunities and Considerations

The inflammatory bowel diseases [IBDs], inclusive of Crohn's disease [CD] and ulcerative colitis [UC], are chronic, progressive immune-mediated diseases associated with high morbidity and substantial economic impact. The pathogenesis implicates a complex interaction between environmental determinants and genetic susceptibility. Of concern, the incidence and prevalence of IBD are increasing globally, with the highest relative increase observed in developing and recently developed countries. One high-risk yet underappreciated population is immigrants from countries of low to high IBD incidence, as evidenced by epidemiologic studies demonstrating higher risk of IBD among second- versus first-generation and younger versus older immigrants from low- to high-incidence countries [LTHICs]. The reasons underlying these emerging patterns among immigrants are incompletely understood and provide enormous opportunities to better define the pathophysiology of IBD and move toward disease prevention or at least earlier diagnosis. The rapidity of this epidemiologic shift in the demographic profile of IBD, which was traditionally a disease of Caucasians in industrialized countries, strongly implicates non-genetic factors and gene-environment interactions in the pathophysiology of IBD among immigrants from LTHICs. The primary objectives of this Viewpoint are to [1] provide a focused overview of IBD epidemiology among immigrants from countries at differential IBD risk; [2] emphasize the potential to advance our understanding of IBD pathogenesis via targeted research efforts to delineate risk and protective determinants in this cohort; and [3] highlight disparities and barriers in IBD care, as well as the economic implications of the rising, yet underappreciated, disease burden among immigrants from LTHICs.

Heat-shock transcription factor 2 promotes sodium butyrate-induced autophagy by inhibiting mTOR in ulcerative colitis

Butyrate-induced autophagy and anti-inflammatory effects of IECs plays an important role in UC. HSP has been proved to be associated with autophagy. HSF2, as an important regulator of HSP, has been determined to be highly expressed in UC. This study was designed to elucidate the relationship between HSF2, butyrate and epithelial autophagy and the potential mechanism of HSF2-related autophagy in UC. The autophagy levels and HSF2 expression in intestinal mucosa were increased in UC patients compared to controls. In DSS colitis models, hsf2^-/- mice exhibited more severe intestinal inflammation and lower autophagy levels than wild-type mice. HSF2 expression could be induced by sodium butyrate and LPS as a dose-response relationship in HT-29 cells, epigenetically via increasing histone acetylation levels at the promoter region by sodium butyrate. Autophagy induced by sodium butyrate was promoted by overexpression HSF2 in HT-29 cells. Moreover, overexpression HSF2 decreased the expression and phosphorylation levels of PI3K, Akt and mTOR induced by sodium butyrate. HSF2 might induced by sodium butyrate and inflammation and played protective roles in UC by enhancing autophagy of IECs. This indicated that HSF2 may be a critical target for autophagy modulation and a new potential therapeutic target in UC.

Fine-scale geographical distribution and ecological risk factors for Crohn's disease in France (2007-2014)

BACKGROUND

Geographical variations in Crohn's disease (CD) suggest that the environment has a role in the pathogenesis of this condition.

AIMS

To describe the spatial distribution and the clustering of CD cases in France, and to assess the relationship between the prevalence of CD and environmental risk factors.

METHODS

We identified all patients with CD included in the French hospital discharge database from 2007 to 2014. Age- and gender-smoothed standardised prevalence ratios over this period were computed for 5610 spatial units. An ecological regression analysis was used to assess the relationship between the risk of CD and ecological variables (health care, latitude, socio-economic deprivation, urbanisation, proportion of agricultural surfaces and density of industries). Local spatial clusters of high-CD prevalence were searched for using elliptic spatial scan statistics and characterised in a hierarchical ascendant classification based on the same ecological variables.

RESULTS

About 129 089 patients with CD were identified, yielding a crude prevalence of 203 per 100 000 inhabitants. The overall spatial heterogeneity was statistically significant (P < .001). An elevated risk of CD was found to be significantly associated with high-social deprivation (relative risk [95% confidence interval] = 1.05 [1.02-1.08]) and high urbanisation (1.09 [1.04-1.14]). Sixteen significant spatial clusters of high-CD prevalence were identified; there were no common ecological variables.

CONCLUSIONS

The geographical distribution of CD prevalence in France is not uniform, and is associated with high levels of social deprivation and urbanisation. Larger ecological databases integrating more detailed environmental and clinical information are needed.

QuantiFERON-TB Gold Test Conversion Is Associated with Active Tuberculosis Development in Inflammatory Bowel Disease Patients Treated with Biological Agents: An Experience of a Medical Center in Taiwan

Taiwan has a lower prevalence of inflammatory bowel disease (IBD) and a higher prevalence of tuberculosis (TB) infection than Western countries. The aim of this study was to investigate the prevalence of latent TB (LTB) and active TB infection in IBD patients treated with biological agents. From January 2000 to September 2018, we retrospectively collected data from IBD patients treated with biological agents at a tertiary referral center. Patients underwent a QuantiFERON-TB Gold test (QFT) to screen for TB infection before and after biological treatment courses. The diagnostic age, sex, body mass index, hepatitis B virus infection, biochemistry profile, treatment regimens, and the results of the QFT were analyzed. Overall, 130 IBD patients who received biological treatment were enrolled. The results of the QFT before biological treatment were determined in 120 patients (92%); of these, 10 were positive (8%), 110 were negative (85%), and 10 were indeterminate (9%). Six patients demonstrated seroconversion after biological treatment, as determined by the QFT. Three patients (2.4%) developed active pulmonary TB after biological treatment. In subgroup analysis, the positive QFT patients had a trend of lower baseline serum C-reactive protein and erythrocyte sedimentation rate levels than the negative QFT group. The present study demonstrates that the prevalence of LTB before and after biological treatment is higher in Taiwan than in most Western countries and similar to other Asian countries. Therefore, screening and monitoring of TB infection are necessary for IBD patients before and during biological treatments in Taiwan.

Relationship(s) between obesity and inflammatory bowel diseases: possible intertwined pathogenic mechanisms

The inflammatory bowel diseases, Crohn's and ulcerative colitis have increased in incidence and prevalence from the mid-eighteen to the late nineteen centuries. From then to the current twenty-first century there has been a more rapid expansion of these disease to areas previously experiencing low rates. This latter expansion coincides with the current obesity pandemic which also began toward the end of the last century. Although the two diseases have radically different frequencies, there are interesting links between them. Four areas link the diseases. On an epidemiological level, IBD tends to follow a north-south gradient raising the importance of vitamin D in protection. Obesity has very weak relationship with latitude, but both diseases follow adult lactase distributions colliding in this plane. Is it possible that obesity (a low vitamin D condition with questionable response to supplements) reduces effects in IBD? On a pathogenic level, pro-inflammatory processes mark both IBD and obesity. The similarity raises the question of whether obesity could facilitate the development of IBD. Features of the metabolic syndrome occur in both, with or without obesity in IBD. The fourth interaction between the two diseases is the apparent effect of obesity on the course of IBD. There are suggestions that obesity may reduce the efficacy of biologic agents. Yet there is some suggestion also that obesity may reduce the need for hospitalization and surgery. The apparent co-expansion of both obesity and IBD suggests similar environmental changes may be involved in the promotion of both.

Mechanism-Based Treatment Strategies for IBD: Cytokines, Cell Adhesion Molecules, JAK Inhibitors, Gut Flora, and More

BACKGROUND

Although TNF inhibitors revolutionized the therapy of inflammatory bowel disease (IBD), we have been reaching a point where other therapies with different mechanisms of action are necessary. A rising number of elderly IBD patients with contraindications to established therapies and a growing group of patients losing response to anti-TNF therapy compel us to find safer, better-tolerated, and, ideally, personalized treatment options. However, in order to choose the right drug to fit a patient, it is indispensable to understand the pathomechanism involved in IBD.

SUMMARY

The aim of this review is to explain the inflammatory signaling pathways in IBD and how to inhibit them with current and future therapeutic approaches. Next to biologic agents targeting inflammatory cytokines (anti-TNF agents, anti-IL-12/-23 agents, and specific inhibitors of IL-23), biologics blocking leukocyte trafficking to the gut (anti-integrin antibodies) are available nowadays. More recently, small molecules inhibiting the JAK-STAT pathway (JAK inhibitors) or preventing lymphocyte trafficking (sphingosine-1-phosphate modulators) have been approved or are under investigation. Furthermore, modifying the microbiota has potential therapeutic effects on IBD, and autologous hematopoietic or mesenchymal stem cell transplantation may be considered for a highly selected group of IBD patients.

KEY MESSAGE

Physicians should understand the different mechanisms of action of the potential therapies for IBD to select the right drug for the right patient.

Systematic review with meta-analysis: association between Helicobacter pylori CagA seropositivity and odds of inflammatory bowel disease

BACKGROUND

Accumulating data support a protective role of Helicobacter pylori against inflammatory bowel diseases (IBD), which might be mediated by strain-specific constituents, specifically cagA expression.

AIM

To perform a systematic review and meta-analysis to more clearly define the association between CagA seropositivity and IBD.

METHODS

We identified comparative studies that included sufficient detail to determine the odds or risk of IBD, Crohn's disease (CD) or ulcerative colitis (UC) amongst individuals with vs without evidence of cagA expression (eg CagA seropositivity). Estimates were pooled using a random effects model.

RESULTS

Three clinical studies met inclusion criteria. cagA expression was represented by CagA seropositivity in all studies. Compared to CagA seronegativity overall, CagA seropositivity was associated with lower odds of IBD (OR 0.31, 95% CI 0.21-0.44) and CD (OR 0.25, 95% CI 0.17-0.38), and statistically nonsignificant lower odds for UC (OR 0.68, 95% CI 0.35-1.32). Similarly, compared to H pylori non-exposed individuals, H pylori exposed, CagA seropositive individuals had lower odds of IBD (OR 0.26, 95% CI 0.16-0.41) and CD (OR 0.23, 95% CI 0.15-0.35), but not UC (OR 0.66, 0.34-1.27). However, there was no significant difference in the odds of IBD, CD or UC between H pylori exposed, CagA seronegative and H pylori non-exposed individuals.

CONCLUSION

We found evidence for a significant association between CagA seropositive H pylori exposure and reduced odds of IBD, particularly CD, but not for CagA seronegative H pylori exposure. Additional studies are needed to confirm these findings and define underlying mechanisms.

The globalization of inflammatory bowel disease: the incidence and prevalence of inflammatory bowel disease in Brazil

PURPOSE OF REVIEW

Epidemiological studies of inflammatory bowel disease (IBD) in newly industrialized countries are limited, due to a lack of medical surveillance systems and reliable and unified registries and databases. In Brazil, reliable data on the incidence and prevalence of Crohn's disease and ulcerative colitis is scarce. The objective of the present review is to describe in detail the available data on the incidence and prevalence of Crohn's disease and ulcerative colitis in Brazil.

RECENT FINDINGS

The authors identified the single four population-based studies which refer to incidence and prevalence of IBD in the country (two from São Paulo, one from Espírito Santo and one from the state of Piauí). These studies demonstrate a remarkable growth in the incidence and estimated prevalence of IBD in Brazil, with higher number of cases in more developed regions.

SUMMARY

The increase in incidence over time and the higher current prevalence are indicative of a historical progression in relation to the number of IBD patients in our country, similar to what was observed in countries from Asia and approximating those of the northern hemisphere. Epidemiological studies with more accurate methodology are needed in Brazil.

Epidemiology and Clinical Outcomes of Inflammatory Bowel Disease: A Hospital-Based Study in Central Taiwan

The incidence and prevalence of inflammatory bowel disease (IBD) are low but increasing in Taiwan. We aimed to investigate the epidemiology and clinical outcomes of IBD in central Taiwan. We retrospectively analyzed patients with IBD diagnosed at our hospital between January 2000 and September 2018. The diagnostic criteria were based on endoscopic and pathologic findings. Clinical characteristics, treatment regimens, and treatment outcomes were analyzed. A total of 190 patients with IBD were enrolled (80 with Crohn's disease (CD) and 110 with ulcerative colitis (UC)). The mean age at diagnosis was 38.4 years (CD: 36 years, UC: 40 years). Male patients accounted for the majority of patients (71.1%). The male-to-female ratio was 3 : 1 for CD and 2.1 : 1 for UC. Current and ever smokers accounted for 30.5% of all patients. Only 4.2% of patients had a family history of IBD. Extraintestinal manifestations (EIMs) were reported in 7.9%, and colorectal cancers (CRCs) were reported in 2.1% of all patients. In patients with CD, the ileal type was the most common disease phenotype (57.5%), and the stricturing type was the most common disease behavior (60.0%). In patients with UC, left-sided colitis was the predominant disease extent (42.7%). The seroprevalence of hepatitis B virus (HBV) was 13.3%. The incidence of perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) in patients with UC was 22%. 5-Aminosalicylic acids were the preferred treatment for UC, whereas corticosteroids, immunomodulators, and biologic agents were preferred for CD. In patients with CD, the bowel resection rate was 38.8%, and the incidence of hip avascular necrosis was 3.8%. In Taiwan, patients with IBD showed a male predominance, lack of familial clustering, a higher prevalence of HBV infection, and a lower prevalence of p-ANCA, EIMs, and CRC. Moreover, a higher incidence of the ileal type with poor outcomes of CD and left-sided predominance in UC were found.

Metabolite-Sensing G Protein-Coupled Receptors Connect the Diet-Microbiota-Metabolites Axis to Inflammatory Bowel Disease

Increasing evidence has indicated that diet and metabolites, including bacteria- and host-derived metabolites, orchestrate host pathophysiology by regulating metabolism, immune system and inflammation. Indeed, autoimmune diseases such as inflammatory bowel disease (IBD) are associated with the modulation of host response to diets. One crucial mechanism by which the microbiota affects the host is signaling through G protein-coupled receptors (GPCRs) termed metabolite-sensing GPCRs. In the gut, both immune and nonimmune cells express GPCRs and their activation generally provide anti-inflammatory signals through regulation of both the immune system functions and the epithelial integrity. Members of GPCR family serve as a link between microbiota, immune system and intestinal epithelium by which all these components crucially participate to maintain the gut homeostasis. Conversely, impaired GPCR signaling is associated with IBD and other diseases, including hepatic steatosis, diabetes, cardiovascular disease, and asthma. In this review, we first outline the signaling, function, expression and the physiological role of several groups of metabolite-sensing GPCRs. We then discuss recent findings on their role in the regulation of the inflammation, their existing endogenous and synthetic ligands and innovative approaches to therapeutically target inflammatory bowel disease.

Herbs-partitioned moxibustion alleviates aberrant intestinal epithelial cell apoptosis by upregulating A20 expression in a mouse model of Crohn’s disease

BACKGROUND

A20 inhibits intestinal epithelial cell apoptosis in Crohn’s disease, and herbs-partitioned moxibustion (HPM) has been demonstrated to be an effective treatment for Crohn’s disease. However, the mechanism by which HPM reduces intestinal epithelial cell apoptosis in Crohn’s disease has not been thoroughly elucidated to date.

AIM

To elucidate whether HPM exerts its effects by upregulating A20 to affect intestinal epithelial cell apoptosis in a Crohn’s disease mouse model.

METHODS

In this study, mice with A20 deletion in intestinal epithelial cells (A20^IEC-KO) were utilized to establish a Crohn’s disease mouse model with 2,4,6-trinitrobenzene sulfonic acid (TNBS) administration, as well as wild-type mice. Mice were randomly divided into normal control (NC), model control (MC), mesalazine (MESA), and HPM groups. The morphology of the colonic mucosa was observed by hematoxylin-eosin staining, and serum endotoxin and apoptosis of epithelial cells were evaluated by enzyme-linked immunosorbent assay and terminal dUTP nick-end labeling assay accordingly. The protein expression levels of A20 and tumor necrosis factor receptor 1 (TNFR1)-related signaling molecules were evaluated by Western blot, and co-expression of A20 and TNFR1-associated death domain (TRADD) and co-expression of A20 and receptor-interacting protein 1 (RIP1) were observed by double immunofluorescence staining.

RESULTS

The intestinal epithelial barrier was noted to have an improvement in the HPM group of wild-type (WT) mice compared with that in A20^IEC-KO mice. Compared with A20 ^IEC-KO HPM mice, serum endotoxin levels and apoptosis percentages were decreased (P < 0.01), A20 expression levels were increased (P < 0.01), and expression of TNFR1, TRADDD, and RIP1 was decreased in the HPM group of WT mice (P_TNFR1 < 0.05, P_TRADD < 0.01, P_RIP1 < 0.01). Both of the co-expression of A20/TRADD and A20/RIP1 showed a predominantly yellow fluorescence in the HPM group of WT mice, while a predominantly red fluorescence was noted in the HPM group of A20^IEC-KO mice.

CONCLUSION

Our findings suggest that HPM in treating Crohn’s disease functions possibly via upregulation of the A20 expression level, resulting in downregulation of TNFR1, TRADD, and RIP1 to alleviate increased cell apoptosis in the intestinal epithelial barrier in Crohn's disease.

Dietary Factors in Sulfur Metabolism and Pathogenesis of Ulcerative Colitis

The biogeography of inflammation in ulcerative colitis (UC) suggests a proximal to distal concentration gradient of a toxin. Hydrogen sulfide (H₂S) has long been considered one such toxin candidate, and dietary sulfur along with the abundance of sulfate reducing bacteria (SRB) were considered the primary determinants of H₂S production and clinical course of UC. The metabolic milieu in the lumen of the colon, however, is the result of a multitude of factors beyond dietary sulfur intake and SRB abundance. Here we present an updated formulation of the H₂S toxin hypothesis for UC pathogenesis, which strives to incorporate the interdependency of diet composition and the metabolic activity of the entire colon microbial community. Specifically, we suggest that the increasing severity of inflammation along the proximal-to-distal axis in UC is due to the dilution of beneficial factors, concentration of toxic factors, and changing detoxification capacity of the host, all of which are intimately linked to the nutrient flow from the diet.

Huangkui Lianchang Decoction Ameliorates DSS-Induced Ulcerative Colitis in Mice by Inhibiting the NF-kappaB Signaling Pathway

BACKGROUND

The nuclear factor kappa beta (NF-κB) signaling pathway plays an important role in ulcerative colitis (UC). Huangkui Lianchang decoction (HLD) is an effective traditional Chinese medicinal compound used in the treatment of UC. HLD has good effects in the clinic, but the mechanism by which HLD acts is unclear. This study aims to reveal the exact molecular mechanism of HLD in the treatment of UC.

METHODS

Mouse ulcerative colitis was induced by dextran sulfate sodium (DSS) and treated with HLD. Intestinal damage was assessed by disease activity index (DAI), colon macroscopic lesion scores, and histological scores. Interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1β were detected in colon tissue using ELISA. Myeloperoxidase (MPO) and superoxide dismutase (SOD) activities in the colonic mucosa were measured. The levels of IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) in the colon were determined by real-time quantitative polymerase chain reaction (qPCR). The expression of NF-κB, IκBα, and p-IκBα in the colon was measured by Western blot.

RESULTS

After treatment with HLD, the DAI scores, macroscopic lesion scores, and histological scores decreased, and the levels of inflammatory cytokines related to the NF-κB signaling pathway, such as IL-6, TNF-α, and IL-1β, as well as those of iNOS and COX-2, were reduced; at the same time, colonic pathological damage was alleviated, and the MPO and SOD activities decreased. Western blot confirmed that HLD can inhibit the NF-κB signaling pathway in DSS-induced ulcerative colitis.

CONCLUSION

HLD can alleviate the inflammation caused by ulcerative colitis. In particular, high doses of HLD can significantly alleviate intestinal inflammation and have comparable efficacy to Mesalazine. We propose that the anti-inflammatory activity of HLD on DSS-induced colitis in mice may involve the inhibition of the NF-κB pathway.

Sex-based differences in the incidence of inflammatory bowel diseases-pooled analysis of population-based studies from the Asia-Pacific region

BACKGROUND

There appear to be differences in risk factor profiles for IBD between Asia-Pacific and Western populations, which might suggest idiosyncrasies in pathogenesis. Recently, sex-based differences in IBD according to the age of diagnosis have been described in Western populations.

AIM

To identify whether sex-based differences in IBD incidence similarly exist across the age spectrum for Asia-Pacific populations.

METHODS

We identified Asia-Pacific population-based cohorts where IBD incidence data stratified by sex were available for the full age spectrum. Cohorts were included only if IBD diagnoses were confirmed and validated. We calculated incidence rate ratios of Crohn's disease (CD) and ulcerative colitis (UC) according to age and compared differences between males and females using random-effects meta-analysis.

RESULTS

Among 567.8 million people from 11 Asia-Pacific countries/provinces/nations, we identified 10 553 incident CD cases (7060 males; 3493 females) and 16 946 incident UC cases (9754 males; 7192 females). Starting in early adolescence until age 50 years, there was a 36%-64% higher incidence of CD in males vs females (P < 0.001). UC incidence ranged from 20%-42% higher in males vs females in the age groups between 15 and 65 years (P < 0.05).

CONCLUSIONS

In a pooled analysis of population-based studies from the Asia-Pacific region, we found a male predominance of both CD and UC for the majority of the age spectrum from adolescence to middle/late-middle age. Additional studies are needed to clarify biological and nonbiological determinants of sex differences in IBD, which might be distinct between Asia-Pacific and Western populations.

Trends in hospitalisation rates for inflammatory bowel disease in western versus newly industrialised countries: a population-based study of countries in the Organisation for Economic Co-operation and Development

BACKGROUND

Hospitalisation rates for inflammatory bowel disease (IBD) vary across the world. We aimed to investigate temporal patterns of hospitalisation for IBD in member countries of the Organisation for Economic Co-operation and Development (OECD).

METHODS

From the OECD database, we assessed IBD-related hospitalisation rates (expressed as annual rates per 100 000 inhabitants) for 34 countries from 1990 to 2016. We calculated mean hospitalisation rates for the period 2010-15 and used joinpoint regression models to calculate average annual percentage changes with 95% CIs.

FINDINGS

Mean hospitalisation rates for IBD from 2010 to 2015 were highest in North America (eg, 33·9 per 100 000 in the USA), Europe (eg, 72·9 per 100 000 in Austria), and Oceania (eg, 31·5 per 100 000 in Australia). Hospitalisation rates for IBD were stabilising or decreasing over time in many countries in these regions but increasing in others. Countries in Asia and Latin America and the Caribbean had the lowest IBD-related hospitalisation rates but the greatest increases in rates over time. For example, Turkey had an annual hospitalisation rate of 10·8 per 100 000 inhabitants and an average annual percentage change of 10·4% (95% CI 5·2-15·9). Similarly, Chile had an annual hospitalisation rate of 9·0 per 100 000 inhabitants and an average annual percentage change of 5·9% (4·9-7·0).

INTERPRETATION

Hospitalisation rates for IBD are high in western countries but are typically stabilising or decreasing, whereas rates in many newly industrialised countries are rapidly increasing, which reflects the known increase in IBD prevalence in these countries. Potential explanations for these trends include changes in the epidemiology of IBD, health-care delivery, and infrastructure in these countries, as well as overall country-specific patterns in hospitalisations and differences between countries in data collection methods.

FUNDING

None.