Identification of Environmental Factors Associated with Inflammatory Bowel Disease in a Southwestern Highland Region of China: A Nested Case-Control Study

The hospitalization burden of inflammatory bowel disease in a southwestern highland region of China: a territory-wide study from 2015 to 2020

Background

Yunnan, a southwest highland and newly industrialized region of China, has an unknown hospitalization burden of inflammatory bowel disease (IBD). The study was conducted to explore territorial hospitalization burden of IBD.

Methods

The formatted medical records of patients with IBD were collected from a territory-wide database in Yunnan Province, China, from 2015 to 2020. General characteristics of the study population were reported using descriptive statistics. To evaluate the length of stay, hospitalization costs, surgery, complications, and trends in patients with inflammatory bowel disease. The logistic regression analysis was established to explore the factors affecting the hospitalization costs.

Results

A total of 12,174 records from 8192 patients were included. The annual hospitalization cost of IBD in Yunnan Province increased significantly from 2015 to 2020. From 2015 to 2020, the regional hospitalization burden of IBD increased, but it represented a decline in cost per hospitalization (r = -0.024, P = 0.008) and the length of stay (r = -0.098, P < 0.001). Surgery rates for hospitalized patients with Crohn's disease (CD) did not decrease (r = -0.002, P = 0.932), and even increased for patients with ulcerative colitis (UC) (r = 0.03, P = 0.002). The costs per hospitalization were $ 827.49 (540.11-1295.50) for UC and $ 1057.03 (644.26-1888.78) for CD. Among the identifiable cost items during the period, drug costs accounted for the highest proportion, accounting for 33% and 37.30% in patients with UC and CD, respectively. Surgical intervention [OR 4.87 (3.75-6.31), P < 0.001], comorbidities [OR 1.72 (1.52-1.94), P < 0.001], complications [OR 1.53 (1.32-1.78), P < 0.001], and endoscopy [OR 2.06 (1.86-2.28), P < 0.001] were predictor of high hospitalization costs.

Conclusion

The increasing burden of IBD is noteworthy a newly industrialized region of China. Interventions targeting surgery, complications, and comorbidities may be effective means of controlling the increasing hospitalization costs of IBD in the regions.

Crude Tieguanyin oolong tea polysaccharides regulate intestinal immune and gut microflora in dextran sulfate sodium-induced mice colitis

BACKGROUND

The global incidence and prevalence of inflammatory bowel diseases (IBDs) have been increasing. Epidemiological studies, clinical trials, and animal experiments have indicated a negative association between the consumption of tea and IBD. This study aims to investigate the protective effects of crude Tieguanyin oolong tea polysaccharides (CTPS) on experimental colitis, while also exploring the underlying mechanisms.

RESULTS

The administration of CTPS significantly alleviated IBD in the mouse model, and was found to regulate T-cell mediated immune responses in the colon by modulating cytokine production associated with T cells. Furthermore, CTPS demonstrated a positive impact on the gut microbiota, reversing the increase in pathogenic Helicobacter and enhancing the relative abundances of beneficial bacteria such as Akkermansia, Lachnospiraceae, and Odoribacter. Oral administration of CTPS also led to an improvement in intestinal metabolism, specifically by increasing the levels of short-chain fatty acids.

CONCLUSION

This study provides the first in vivo evidence of the protective effects of CTPS on colitis in mice. The effects are likely facilitated through the regulation of T cell-mediated responses and modulation of the gut microbiota, suggesting that CTPS may be a potential preventive and therapeutic approach for IBD. © 2023 Society of Chemical Industry.

Antibiotic Exposure and Risk of New-Onset Inflammatory Bowel Disease: A Systematic Review and Dose-Response Meta-Analysis

BACKGROUND & AIMS

The association between antibiotic exposure and inflammatory bowel disease (IBD) remains controversial, especially whether there is a dose-response relationship. We aimed to conduct a systematic review and meta-analysis to thoroughly evaluate the risk of new-onset IBD associated with antibiotic exposure.

METHODS

Four databases were searched from their inception to September 30, 2023 for all relevant studies. The risk estimates were pooled together using random-effects models, and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated, stratified by IBD subtype, age, exposure period, study type, and antibiotic classes. Dose-response relationship between the number of antibiotic prescriptions and IBD risk was assessed using generalized least squares regression analysis.

RESULTS

Twenty-eight studies involving 153,027 patients with IBD were included. Antibiotic exposure was significantly associated with an increased risk of new-onset IBD for prescription-based studies (pooled OR, 1.41; 95% CI, 1.29-1.53) and for questionnaire-based studies (pooled OR, 1.35; 95% CI, 1.08-1.68). This association existed for both Crohn's disease and ulcerative colitis, as well as in children and adults for prescription-based studies. The majority of antibiotic classes were associated with an increased IBD risk, with metronidazole (OR, 1.70; 95% CI, 1.38-2.10) and quinolones (OR, 1.56; 95% CI, 1.37-1.77) having relatively higher risk estimates. A positive nonlinear dose-response association was observed between the number of antibiotic prescriptions and IBD risk.

CONCLUSIONS

Antibiotic exposure was significantly associated with an increased risk of new-onset IBD, and a positive nonlinear dose-response relationship was observed. Antibiotic stewardship may be important for reducing IBD risk.

Fatigue, Physical Activity, and Quality of Life in Patients with Inflammatory Bowel Disease: A Cross-Sectional Study

Purpose

The benefits of physical activity (PA) are widely recognized, but the intensity of PA in inflammatory bowel disease (IBD) patients with varying disease activity levels remains controversial. We aimed to investigate the relationship between PA levels, fatigue, and other health-related quality of life (QoL) in Chinese IBD patients.

Patients and Methods

The study is a cross-sectional investigation conducted at a comprehensive IBD diagnosis and treatment facility in East China, spanning from August 2022 to February 2023. A total of 245 participants were initially enrolled, and after excluding individuals with incomplete data about crucial exposure and outcome variables, the final sample size amounted to 237. Participants were provided with a questionnaire encompassing sociodemographic factors, clinical information, the International Physical Activity Questionnaire (IPAQ), the Multidimensional Fatigue Inventory (MFI-20), and the Inflammatory Bowel Disease Questionnaire (IBDQ). Correlation analysis was employed to assess the relationship between variables.

Results

A majority of participants (144) exhibited low levels of PA. Furthermore, 40.5% of all participants reported experiencing fatigue. Individuals with low levels of PA had an average MIF-20 score of 62.9±16.0. Correlation analysis showed that PA was significantly and negatively associated with fatigue (r = -0.224, p < 0.001). Additionally, PA was also negatively correlated with anxiety (r = -0.150, p < 0.05) and depression (r = -0.242, p < 0.001). On the other hand, PA was positively correlated with quality of life (QoL) (r = 0.171, p < 0.01). Furthermore, our analysis indicated that sleep disorders were positively associated with both anxiety (r = 0.349, p < 0.01) and depression (r = 0.354, p < 0.001).

Conclusion

The levels of PA are significantly low, and there is a high prevalence of fatigue among individuals with IBD. PA in IBD showed a strong negative correlation with fatigue and a strong positive correlation with quality of life.

Derivatives of benzamide of the extracts from the bark of Maqian (Zanthoxylum myriacanthum var. pubescens)

Two newly discovered natural derivatives of benzamide, O-Ethyltembamide (1) and N-[(Z)-2-(4-Methoxyphenyl)vinyl]benzamide(2), together with four known compounds, hortiamide (3), N-[(E)-2-(4-Methoxyphenyl)vinyl] benzamide (alatamide) (4), dihydroaltamide (5) and tembamid (6), were isolated from the barks of of Zanthoxylum myriacanthum var. pubescens (Huang) Huang. Their structures were determined on the basis of spectral data. The anti-inflammatory activity of the isolated compounds (1-6) were scanned against NO production in LPS-activated RAW 264.7 macrophages by MTS assay, however no significant activities were observed.

Association between prior appendectomy and the risk and course of Crohn's disease: A systematic review and meta-analysis

BACKGROUND AND AIMS

The appendix has an important immune function in both health and disease, and appendectomy may influence microbial ecology and immune function. This meta-analysis aims to assess the association between appendectomy and the risk and course of Crohn's disease (CD).

METHODS

PubMed, EMBASE, and the Cochrane Library were used to identify all studies published until June 2022. Data from studies evaluating the association between appendectomy and CD were reviewed.

RESULTS

A total of 28 studies were included in the final analysis, comprising 22 case-control and 6 cohort studies. A positive relationship between prior appendectomy and the risk of developing CD was observed in both case-control studies (odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.22-2.08) and cohort studies (relative risk [RR]: 2.28, 95% CI: 1.66-3.14). The elevated risk of CD persisted 5 years post-appendectomy (RR = 1.24, 95% CI: 1.12-1.36). The risk of developing CD was similarly elevated regardless of the presence (RR = 1.64, 95% CI: 1.17-2.31) or absence (RR = 2.77, 95% CI: 1.84-4.16) of appendicitis in patients. Moreover, significant differences were found in the proportion of terminal ileum lesions (OR = 1.63; 95% CI: 1.38-1.93) and colon lesions (OR = 0.70; 95% CI: 0.5-0.84) between CD patients with appendectomy and those without appendectomy.

CONCLUSIONS

The risk of developing CD following an appendectomy is significant and persists 5 years postoperatively. Moreover, the elevated risk of CD may mainly occur in the terminal ileum.

miR-642a-5p increases glucocorticoid sensitivity by suppressing the TLR4 signalling pathway in THP-1 cells

The incidence rate of ulcerative colitis (UC) is increasing annually, and glucocorticoid (GC) resistance (GCR) is a common cause of UC-induced remission failure. Our previous studies have shown that the expression of miR-642a-5p is downregulated in UC with GCR, suggesting that miR-642a-5p may be related to the GC response. Therefore, we investigated the mechanism by which miR-642a-5p regulates the GC response in THP-1 cells.

We found that after treatment with miR-642a-5p mimics and DEX, the expression levels of glucocorticoid receptor (GR) in the nucleus and NF-κB p65 and p50 in the cytoplasm were increased (P < 0.05). miR-642a-5p mimics transfected into THP-1 cells could synergize with dexamethasone (DEX) to reduce lipopolysaccharide (LPS)-induced inflammatory factor levels such as TNF-α, IL-1β, IL-6 and IL-12 (P < 0.05). Bioinformatics analysis and luciferase reporter assays confirmed that TLR4 is a target gene of miR-642a-5p. miR-642a-5p mimic pretreatment enhanced the inhibitory effect of DEX on TLR4 induced by LPS and inhibited the expression of TLR4 on the cell surface (P < 0.05). Additionally, miR-642a-5p further prevented the nuclear import of NF-κB P65 and inhibited the phosphorylation of ERK, p38 and JNK.

These results suggest that miR-642a-5p can inhibit the inflammation by suppressing the TLR4 signalling pathway in THP-1 cells. It also highlights the TLR4 signalling pathway as a potential therapeutic target in anti-inflammation.

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miR-642a-5p can inhibit the TLR4 signalling pathway induced by LPS and increase the glucocorticoid sensitivity in THP-1 cells.

Mesenchymal stem/stromal cells in the pathogenesis and regenerative therapy of inflammatory bowel diseases

Inflammatory bowel diseases (IBDs) represent a group of chronic inflammatory disorders of the gastrointestinal (GI) tract including ulcerative colitis (UC), Crohn’s disease (CD), and unclassified IBDs. The pathogenesis of IBDs is related to genetic susceptibility, environmental factors, and dysbiosis that can lead to the dysfunction of immune responses and dysregulated homeostasis of local mucosal tissues characterized by severe inflammatory responses and tissue damage in GI tract. To date, extensive studies have indicated that IBDs cannot be completely cured and easy to relapse, thus prompting researchers to find novel and more effective therapeutics for this disease. Due to their potent multipotent differentiation and immunomodulatory capabilities, mesenchymal stem/stromal cells (MSCs) not only play an important role in regulating immune and tissue homeostasis but also display potent therapeutic effects on various inflammatory diseases, including IBDs, in both preclinical and clinical studies. In this review, we present a comprehensive overview on the pathological mechanisms, the currently available therapeutics, particularly, the potential application of MSCs-based regenerative therapy for IBDs.

Active and passive smoking and risk of ulcerative colitis: A case-control study in Japan

BACKGROUND AND AIM

Although an inverse relationship between current smoking and the development of ulcerative colitis (UC) has been shown in North America and Europe, evidence is limited in Asian countries, where the incidence of UC is rapidly increasing. This Japanese case-control study examined the association between active and passive smoking and risk of UC.

METHODS

A self-administered questionnaire was used to obtain information on smoking and potential confounding factors in 384 cases with a diagnosis of UC within the past 4 years and 665 controls.

RESULTS

Compared with having never smoked, having ever smoked was associated with an increased risk of UC (adjusted odds ratio [OR] = 1.70, 95% confidence interval [CI]: 1.23-2.37). No association was observed between current smoking and risk of UC, but former smokers had a significant elevation in risk (adjusted OR = 2.40, 95% CI: 1.67-3.45). There was a positive dose-response relationship with pack-years smoked (P for trend = 0.006). Among never smokers, passive smoking exposure at home was significantly associated with an increased risk of UC (adjusted OR = 1.90, 95% CI: 1.30-2.79). A significant dose-response gradient was also observed between pack-years of passive smoking at home and risk of UC (P for trend = 0.0003).

CONCLUSIONS

We confirmed that former smoking elevated the risk of UC, whereas an inverse association between current smoking and the risk of UC did not reach a statistically significant level. Passive smoking may be associated with an increased risk of UC.

Systematic review with meta-analysis: environmental and dietary differences of inflammatory bowel disease in Eastern and Western populations

BACKGROUND

While the incidence of inflammatory bowel disease (IBD) has stabilised in the West, it is still increasing in several newly industrialised countries.

AIMS

To investigate whether the environmental and dietary risk factors for IBD differ between Eastern and Western populations METHODS: We systematically searched PubMed, Embase, and Web of Science for studies published from inception through June 30, 2020. Data were pooled using a random effects model.

RESULTS

Overall, 255 studies were assessed. We identified 25 risk factors for IBD, seven of which were noted in both Eastern and Western populations: family history of Crohn's disease [CD] or ulcerative colitis [UC], former smoking (CD/UC), smoking (CD), appendicectomy (CD), tonsillectomy (CD), meat and meat products (CD), and vitamin D deficiency (UC). The remaining factors, including urban living, current smoking, antibiotics, oral contraceptives, caesarean section, isotretinoin, total energy, fat, cholesterol, fatty acids and their sub-classifications, eggs, and soft drinks, were associated with an increased risk of IBD in Western or Eastern populations only. We identified 21 protective factors for IBD, among which eight were common in the East and West: farm animals (CD/UC), Helicobacter pylori infection (CD/UC), multiple births (CD), physical activity (CD), history of breastfeeding (CD), pets (UC), current smoking (UC), and coffee intake (UC). Ten factors conferred protection against IBD in Western populations only, whereas eight factors conferred protection against IBD in Eastern populations only.

CONCLUSIONS

Numerous environmental and dietary factors influenced the development of IBD in both Western and Eastern populations, whereas certain factors influenced IBD risk differently in these populations.

Exploring Links Between Industrialization, Urbanization, and Chinese Inflammatory Bowel Disease

Background: Evidence is emerging that the incidence of inflammatory bowel diseases (IBD) is dramatically increased in China, but with a geographic variation. Objectives: We performed a review to summarize the link of accelerated industrialization, urbanization to changing trends in the incidence of IBD over the last three decades. Methods: An electronic database search was performed in PubMed, Medline, EMBASE and Google Scholar (for English literature) and the China Science Periodical Database in Wanfang Data (for Chinese literature) from January 1990 to June 2020. Results: By systematically analyzing the changing trends of gross domestic product (GDP) or GDP per capita, population migration from rural areas to cities and increasing incidence of IBD in parallel in different Chinese regions, an association between accelerated industrialization and urbanization and rising rate of IBD was shown. In which, rates of IBD incidence were higher in provinces with a high value of GDP per capita than those provinces with a low value of GDP per capita. Analysis of available epidemiological data revealed that the incidence of IBD was rising in parallel with increasing trends of both gross products of industry and urban population in Yunnan Province in a 14-year interval. Further evidence suggested that industrialization- and urbanization-induced subsequent changes in environmental factors, e.g., Westernized dietary habits and obesity, and work-related stress, might contribute to the increased risk of IBD in China. In addition, the preliminary results showed that urbanization and Westernized dietary habits might induce significant changes in gut microbiota profile that are possibly to increase the risk for IBD in Chinese. Conclusions: Existing evidence to suggest that accelerated industrialization/urbanization is associated with the increasing incidence of IBD in China, which provides novel insights to study the possible mechanisms for the recent increasing incidence of IBD in newly industrialized and urbanized developing countries. In the future, the interaction between relevant environmental factors e.g., air/water pollution and IBD susceptibility genes in Chinese should be examined.

Ethnic Differences in the Smoking-related Risk of Inflammatory Bowel Disease: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

The association between smoking and inflammatory bowel disease [IBD] relies on old meta-analyses including exclusively non-Jewish White populations. Uncertainty persists regarding the role of smoking in other ethnicities.

METHODS

We systematically searched Medline/PubMed, Embase, and Scopus for studies examining tobacco smoking and the risk of developing IBD, ie, Crohn's disease [CD] or ulcerative colitis [UC]. Two authors independently extracted study data and assessed each study's risk of bias. We examined heterogeneity and small-study effect, and calculated summary estimates using random-effects models. Stratified analyses and meta-regression were employed to study the association between study-level characteristics and effect estimates. The strength of epidemiological evidence was assessed through prespecified criteria.

RESULTS

We synthesised 57 studies examining the smoking-related risk of developing CD and UC. Non-Jewish White smokers were at increased risk of CD (29 studies; relative risk [RR]: 1.95, 95% confidence interval [CI]: 1.69‒2.24; moderate evidence). No association was observed in Asian, Jewish. and Latin-American populations [11 studies; RR: 0.97; 95% CI: 0.83-1.13], with no evidence of heterogeneity across these ethnicities. Smokers were at reduced risk of UC [51 studies; RR: 0.55, 95% CI: 0.48-0.64; weak evidence] irrespectively of ethnicity; however, cohort studies, large studies, and those recently published showed attenuated associations.

CONCLUSIONS

This meta-analysis did not identify any increased risk of CD in smokers in ethnicities other than non-Jewish Whites, and confirmed the protective effect of smoking on UC occurrence. Future research should characterise the genetic background of CD patients across different ethnicities to improve our understanding of the role of smoking in CD pathogenesis.

Epidemiology, burden of disease, and unmet needs in the treatment of ulcerative colitis in Asia

INTRODUCTION

Ulcerative colitis (UC) is an idiopathic, chronic inflammatory disease of the colon, characterized by relapsing and remitting symptoms. Although traditionally viewed as a Western disease, the incidence and prevalence of UC is increasing in developing regions, including Asian countries.

AREAS COVERED

A PubMed search identified articles describing epidemiology, disease burden, patient demographics, clinical characteristics, risk factors, and treatment of UC across Asia. We review the epidemiology and disease course of UC across Asia, including region-specific factors that may aid development of more cost-effective treatment approaches tailored to the needs of Asian populations.

EXPERT OPINION

The opinion of non-Pfizer-affiliated practicing gastroenterologists is that epidemiological data from the last four decades have shown 1.5-fold to almost 20-fold increases in the incidence and prevalence of UC in some Asian countries, although prevalence remains generally lower than in the West. As the prevalence of UC rises, so will overall healthcare costs. Disparities in healthcare systems and funding mean that different Asian countries face unique challenges in how best to use available resources, including selection from a growing number of emerging treatment options. More clinical trial and real-world data are required to help define treatment approaches that will most benefit Asian populations.

Correlation between antibiotic use in childhood and subsequent inflammatory bowel disease: a systematic review and meta-analysis

Background: Antibiotic use leads to a cascade of inflammatory reaction in the gastrointestinal tract due to its association with a temporary disruption of human microbiome.Objectives: To explore the undetermined correlation between antibiotic use in childhood and subsequent inflammatory bowel disease (IBD).Methods: PUBMED, EMBASE and Cochrane Central Register of Controlled Trials were searched to identify related articles. We extracted and pooled the (adjusted) odds ratio (OR) and (adjusted) risk ratio (RR).Results: This systematic review and meta-analysis included 11 studies. The pooled OR of all 11 studies was 1.5 (95% confidence interval (CI): 1.22-1.85). The pooled ORs of the subsequent Crohn's disease and ulcerative colitis after antibiotic use in childhood were 1.59 (95% CI: 1.06-2.4) and 1.22 (95% CI: 0.82-1.8). The sensitivity analysis showed no change. The meta-regression showed there was not statistical significance for the publication year, research area and research methods. Egger's test showed publication bias in the IBD studies (p  =  .006  <  .05) but no publication bias for the CD (p  =  .275>.05) and UC studies (p  =  .537>.05).Conclusions: There was a positive association between antibiotic use in childhood and the subsequently risk of Crohn's disease in non-European countries in the west during 2010-2013. Children in the United States taking antibiotics will have a higher risk of subsequently IBD than Europe, Asia and Australia. Registration number: CRD42019147648 (PROSPERO).

Antibiotic Use in Childhood and Adolescence and Risk of Inflammatory Bowel Disease: A Case-Control Study in the UK Clinical Practice Research Datalink

BACKGROUND

Inflammatory bowel disease (IBD) causes serious morbidity and disability, and the incidence is increasing. The disease etiology is not well understood, though inflammatory reactions after antibiotic exposure may be associated with development of IBD. We investigated the association between IBD and prior antibiotic use.

METHODS

We conducted this case-control study among individuals in the United Kingdom Clinical Practice Research Datalink GOLD (CPRD GOLD). Each case of IBD was matched to 4 controls on age, sex, general practice, and registration year in the CPRD GOLD. Antibiotic exposure was classified by ever or never use, number of prescriptions, and class of antibiotic before the index date. Odds ratios were calculated using conditional logistic regression.

RESULTS

We identified 461 cases of ulcerative colitis (UC) and 683 cases of Crohn's disease (CD). There was no association between ever use of any antibiotic and UC (odds ratio [OR], 1.02; 95% confidence interval [CI], 0.72-1.44) or CD (OR, 1.01; 95% CI, 0.73-1.39) compared with never use. A slightly increased CD risk was observed among ever users of quinolones (OR, 1.76; 95% CI, 1.00-3.11) and metronidazole (OR, 1.43; 95% CI, 0.87-2.34) compared with never users. CD was associated with antibiotic exposure before age 5 (OR, 2.20; 95% CI, 0.75-6.43) in an analysis restricted to individuals followed from birth.

CONCLUSIONS

There was no association between UC or CD and overall prior use of antibiotics, though prior use of metronidazole and quinolones was associated with a slightly increased risk of CD. Antibiotic use in early childhood may increase the risk of CD.

Environmental Factors in Romanian and Belgian Patients with Inflammatory Bowel Disease - a Retrospective Comparative Study

Background:Several environmental factors have been associated with onset of inflammatory bowel diseases (IBD): smoking, hygiene, microorganisms, oral contraceptive pills (OCPs), non-steroid anti-inflammatory drugs, antibiotics, appendectomy, diet, breastfeeding, vitamin D, stress and ambient air pollution. The aim of this study was to investigate the prevalence of these factors in a Romanian and Belgian population with IBD. Material and methods:A total of 129 patients with an IBD diagnosis (76 from Romania and 53 from Belgium) participated in an interview and were asked to fill in a questionnaire regarding environmental factors before and after the onset of IBD; 35 Romanian and 21 Belgian healthy individuals constituted the control group. Results:A total of 40 patients with ulcerative colitis (UC) and 89 with Crohn's disease (CD) were included. Gender distribution was 43% males and 57% females. They had a median age of 42 years (range between 19-74 years), a median disease duration of eight years and 79% were in clinical remission. Both Romanian and Belgian IBD patients reported an increased antibiotic consumption before IBD onset compared to controls: 58% vs 10% (p<0.001) and 51% vs 5% (p<0.001), respectively. Belgian IBD patients declared significantly more frequent OCP use (53% vs 9%, p <0.001), they were breastfed in a lower proportion (49% vs 76%, p <0.001) and had experienced a higher level of psychosocial stress (p<0.001). Conclusion:Antibiotic consumption before IBD onset may play a pivotal role in IBD development in both Romanian and Belgian populations. In Belgian patients, OCP consumption, a higher level of psychosocial stress and lack of breastfeeding may also be involved.

Low dose Epigallocatechin Gallate Alleviates Experimental Colitis by Subduing Inflammatory Cells and Cytokines, and Improving Intestinal Permeability

Background: In this study, we investigate the impact of epigallocatechin gallate (EGCG), the most abundant and potent catechin in green tea, on a mouse model of inflammatory bowel disease (IBD) and the underlying mechanisms of action. Methods: C57BL/6J mice were subjected to dextran sulfate sodium (DSS)-induced IBD-like disease and then randomly divided into three groups: Model group (MD), low-dose EGCG group (LE, 20 mg/kg/d), and high-dose EGCG group (HE, 50 mg/kg/d). DSS-induced clinical and macroscopic changes were monitored daily. Intestinal permeability was assessed by FITC-Dextran assay. Results: Both high- and low-dose EGCG treatment alleviated clinical manifestations including body weight loss and disease activity index (DAI) of DSS-induced colitis. The DAI score was significantly improved after two days of EGCG treatment. At the end of the study, the macroscopic severity score (MSS) of HE and LE treatment groups were 2.4 ± 1.2, and 2.2 ± 1.0, respectively, significantly lower than that of the controls (5.0 ± 2.1). EGCG treatment also prevented colon shortening, and improved intestinal permeability and histopathological changes. In addition, EGCG treatment attenuated colon inflammation by suppressing colonic levels of pro-inflammatory cytokines IL-6, MCP-1, and TNF-alpha, and inhibited CD3+ T cell and CD68+ macrophage infiltration. Conclusion: EGCG is effective in inflammatory colitis because it reduces cellular and molecular inflammation, and reduces intestinal permeability.

Prior Appendectomy and the Onset and Course of Crohn's Disease in Chinese Patients

Background and Aim

The relationship between prior appendectomy and Crohn's disease (CD) has previously revealed conflicting findings. The present study investigates the relationship between prior appendectomy and CD development in Chinese patients.

Methods

A retrospective case-control study was performed to compare prior appendectomy rate between CD patients and age- and gender-matched controls at two Chinese hospitals. The clinical course of CD was determined in patients who underwent and did not undergo appendectomies before CD diagnosis.

Results

A total of 617 CD patients and 617 controls were included. The appendectomy rate before CD diagnosis in patients was higher, when compared to controls (6.65% versus 3.73%, P = 0.033). Appendectomy was a risk factor for the onset of CD independent of smoking in the multivariate analysis (OR: 1.878; 95% CI: 1.111–3.174; P = 0.019). Appendectomies were performed closer to the date of CD diagnosis in the trend test (P = 0.039). The rate of appendectomy within one year or 1-5 years before CD diagnosis was higher in patients when compared to that in controls (0.97% versus 0%, P = 0.031; 1.13% versus 0.32%, P = 0.180). However, the rate of appendectomy over five years before CD diagnosis was close to controls (4.54% versus 3.40%, P = 0.392). No significant differences in disease location, behavior, medication, and intestinal resection between appendectomy and nonappendectomy CD patients were found, even in the subgroup analysis by age of appendectomy.

Conclusion

Prior appendectomy is a risk factor for the onset of CD. However, the appendectomy rate only increased for a short duration before CD diagnosis, likely reflecting a diagnostic bias. Prior appendectomy did not influence the features or course of CD.

The association between environmental factors and the development of Crohn's disease with focusing on passive smoking: A multicenter case-control study in Japan

BACKGROUND

The number of patients with Crohn's disease (CD) in Japan has recently been increasing. We examined the association between environmental factors and the development of CD in Japanese focusing on passive smoking.

METHODS

We conducted a multicenter case-control study and compared the environmental factors of 93 cases who were newly diagnosed with CD to the environmental factors of 132 controls (hospital-, age-, and sex-matched patients with other diseases). The odds ratio (OR) of each factor for the development of CD and the 95% confidence interval (CI) were calculated using a logistic regression model. The association between the details of passive smoking history and the development of CD was examined for those who had an active smoking history "no". Odds ratios of number of passively smoked cigarettes (per day), time of passive smoking (per day) and period of passive smoking (year) were calculated using "passive smoking 'No'" as a reference.

RESULTS

History of appendicitis, family history of inflammatory bowel disease, and active smoking history were not significantly associated with the development of CD. Drinking history showed a decreased OR for the development of CD (0.39, 0.19-0.77). "Passive smoking Yes" showed significantly increased OR (2.49, 1.09-5.73). Regarding the association between passive smoking and the development of CD, the OR increased as the number of cigarettes per day, smoking time per day, and smoking duration increased, and there was a dose-response relationship (trend P = 0.024, 0.032, 0.038).

CONCLUSIONS

The association between environmental factors and the development of CD among Japanese was examined by case-control study. It was suggested that the passive smoking history may be associated to the development of CD.

Emerging trends of inflammatory bowel disease in South Korea: A nationwide population-based study

BACKGROUND AND AIM

Little is known regarding the exact burden of inflammatory bowel disease (IBD) in Asian countries because previous epidemiologic studies were hospital based. We aimed to develop and validate an operational definition of IBD cases from health insurance claims data and to examine the epidemiological features of IBD in Korea.

METHODS

We analyzed stratified sample data from the Korean Health Insurance Review and Assessment (2010-2016) database using 12 different definitions and applied the best definition to the entire (2007-2016) dataset.

RESULTS

The definition that combined the International Classification of Disease 10th revision code with IBD-specific medications had the best performance characteristics among the 12 tested definitions. During the 8-year study period, IBD prevalence increased from 25 345 in 2009 to 47 444 in 2016. Over that period, the prevalence of Crohn's disease increased 1.9-fold (from 16.0/100 000 in 2009 to 29.6/100 000 in 2016) and that of ulcerative colitis increased 1.6-fold (from 41.4/100 000 in 2009 to 66.0/100 000 in 2016). Similarly, the estimated incidence of Crohn's disease also increased 1.2-fold (from 2.4 to 2.9 per 100 000) and that of ulcerative colitis rose 1.3-fold (from 4.0 to 5.3 per 100 000). During the study period, the predominant increase in IBD incidence was among younger individuals, especially those aged < 30 years.

CONCLUSION

Patients with IBD can be accurately identified using Korean insurance claims data by combining information regarding the International Classification of Disease 10th revision codes and the IBD medications used. The prevalence of IBD continues to increase, with an apparent shift toward younger (< 30 years) age groups.

THE EFFECT OF DAILY PHYSICAL ACTIVITY ON THE ACTIVITY OF INFLAMMATORY BOWEL DISEASES IN THERAPY-FREE PATIENTS

It has been suggested that various environmental factors play a very important role in the etiology of inflammatory bowel diseases (IBDs) and that they have a significant effect on the course of these diseases. The aim of this study was to investigate the effect of daily physical activity on the activity of IBDs in therapy-free patients. This cross-sectional population based study was conducted in eastern Croatia from January to June 2016. The study included 312 patients, mean age 49.9±15.0 years, 53.2% of males and 46.8% of females; there were 63.4% of ulcerative colitis (UC) and 36.6% of Crohn’s disease (CD) patients. Sociodemographic characteristics of patients, data on their daily physical activity and type of therapy taken were collected through a specifically designed and validated questionnaire, while the activity of UC and CD was evaluated using the Mayo index and Harvey-Bradshaw index. The study showed that 24.0% of patients were not taking therapy. Daily physical activity was connected to IBD in study patients when taking both diseases collectively (Fisher exact test; p<0.001), as well as to the inactivity of CD (Fisher exact test; p=0.001) and UC (Fisher exact test; p=0.006), when observing each disease separately. Daily physical activity was connected to the inactivity of IBDs in patients not taking therapy. It is necessary to educate all IBD patients about the importance of physical activity in order to control their disease.

Beverage intake and risk of Crohn disease: A meta-analysis of 16 epidemiological studies

Epidemiological studies were controversial in the association between beverage intake and risk of Crohn disease (CD). This study aimed to investigate the role of beverage intake in the development of CD. A systematic search was conducted in public databases to identify all relevant studies, and study-specific relative risks (RRs) and 95% confidence intervals (CIs) were pooled using a random-effects model. Sixteen studies were identified with a total of 130,431 participants and 1933 CD cases. No significant association was detected between alcohol intake and CD risk (RR for the highest vs the lowest consumption level: 0.85, 95% CI 0.68-1.08), and coffee intake and the risk (RR 0.82, 95% CI 0.46-1.46). High intake of soft drinks was associated with CD risk (RR 1.42, 95% CI 1.01-1.98), and tea intake was inversely associated with CD risk (RR 0.70, 95% CI 0.53-0.93). In conclusion, high intake of soft drinks might increase the risk of CD, whereas tea intake might decrease the risk.

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.

Smoking and Inflammatory Bowel Disease: A Comparison of China, India, and the USA

BACKGROUND

Cigarette smoking is thought to increase the risk of Crohn's disease (CD) and exacerbate the disease course, with opposite roles in ulcerative colitis (UC). However, these findings are from Western populations, and the association between smoking and inflammatory bowel disease (IBD) has not been well studied in Asia.

AIMS

We aimed to compare the prevalence of smoking at diagnosis between IBD cases and controls recruited in China, India, and the USA, and to investigate the impact of smoking on disease outcomes.

METHODS

We recruited IBD cases and controls between 2014 and 2018. All participants completed a questionnaire about demographic characteristics, environmental risk factors and IBD history.

RESULTS

We recruited 337 participants from China, 194 from India, and 645 from the USA. In China, CD cases were less likely than controls to be current smokers (adjusted odds ratio [95% CI] 0.4 [0.2-0.9]). There was no association between current or former smoking and CD in the USA. In China and the USA, UC cases were more likely to be former smokers than controls (China 14.6 [3.3-64.8]; USA 1.8 [1.0-3.3]). In India, both CD and UC had similar current smoking status to controls at diagnosis. Current smoking at diagnosis was significantly associated with greater use of immunosuppressants (4.4 [1.1-18.1]) in CD cases in China.

CONCLUSIONS

We found heterogeneity in the associations of smoking and IBD risk and outcomes between China, India, and the USA. Further study with more adequate sample size and more uniform definition of smoking status is warranted.

A Systematic Review of Epidemiology and Risk Factors Associated With Chinese Inflammatory Bowel Disease

Background: Recent epidemiological data have revealed a dramatically rising prevalence and incidence of inflammatory bowel diseases (IBDs) in Mainland China, a rapidly growing industrialized region, over the last two decades. Objectives: We performed a systematic review to investigate the changing trends in the incidence of IBD in Mainland China and summarized the recent findings in risk factors associated with Chinese IBD. Methods: Relevant references were obtained from an electronic database search via MEDLINE and EMBASE (for English literatures), the China Academic Journals Full-text Database (CJFD) and the China Science Periodical Database (CSPD) in Wanfang Data (for Chinese literatures). Results: Total 1,584 abstracts in Chinese and 171 abstracts in English were collected. Eight full-text with epidemiological data, 25 with risk factor data in Chinese and 7 full-text with epidemiological data, 12 with risk factor data in English were finally identified and included for analysis. Data from included epidemiological studies has showed a striking increase in the incidence rate of IBD in Mainland China over time, and current incidence rates for IBD, UC, and CD were 1.80 (IBD), 1.33 (UC), and 0.46/1,000,000 (CD), though it varies among regions and ethnic minority populations. In addition, several risk factors including environmental factors, diet, intestinal infectious agents, hygiene, stress, and lifestyle have been reported to be associated with the increased incidence of Chinese IBD. Conclusion: This systematic review revealed an increased incidence of IBD in Mainland China. Although it is still lower than that in the Western world, however, China has a huge population; therefore, the total number of IBD patients might not be so little as previously thought and the disease burden of IBD in China is likely underestimated. HIGHLIGHTS Recent epidemiological data have revealed a dramatically rising prevalence and incidence of inflammatory bowel diseases (IBD) in Mainland China, a rapidly growing industrialized region, over the last two decades.This systematic review based on recent epidemiological data has revealed a striking increase in the incidence rate of IBD in Mainland China, though it varies among regions and ethnic minority populations.Several potential risk factors of IBD including environmental factors, diet, intestinal infectious agents, hygiene, stress, and lifestyle have been reported to be associated with the increased incidence of Chinese IBD.This systematic review on epidemiologic and risk factor studies has expanded understanding of the occurrence, distribution, geographic variance and risk factors of Chinese IBD and will provide clinicians important information in understanding current status of IBD in Mainland China.

Systematic review with meta-analysis: association between acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs) and risk of Crohn's disease and ulcerative colitis exacerbation

BACKGROUND

Unlike acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs) have generally been thought to be associated with increased risk of IBD exacerbation.

AIM

To carry out a systematic review and meta-analysis of previous studies examining the association between acetaminophen and NSAIDs including cyclooxygenase (COX-2) inhibitors use, and risk of Crohn's disease (CD) and ulcerative colitis (UC) exacerbation.

METHODS

We identified published manuscripts and abstracts through 1 March 2017 by systematic search of Medline, Embase, Cochrane and other trial registries. Quality assessment was done using Newcastle-Ottawa scale and random-effect meta-analysis using pooled relative risks (RRs) and 95% CIs were calculated.

RESULTS

Eighteen publications between years 1983 and 2016 were identified. For the meta-analysis, pooled RRs of disease exacerbation with NSAIDs use were (1.42, 95% CI, 0.65-3.09), I2  = 60.3% for CD, and (1.52, 95% CI, 0.87-2.63), I2  = 56.1% for UC. The corresponding values for acetaminophen use were (1.40, 95% CI, 0.96-2.04), I2  = 45.6% for UC, and (1.56, 95% CI, 1.22-1.99), I2  = 0.0% for IBD. Sensitivity analyses limited to studies with low risk of bias showed a significantly increased risk of CD exacerbation (1.53, 95% CI, 1.08-2.16) but not UC (0.94, 95% CI, 0.36-2.42) with NSAIDs use.

CONCLUSIONS

Contrary to generally accepted belief, we did not find a consistent association between NSAIDs use and risk of CD and UC exacerbation. There was also no consistent evidence for association with acetaminophen although further studies are needed.

Differential expression of serum microRNAs in glucocorticoid-resistant patients with ulcerative colitis

Inflammatory bowel disease (IBD) includes ulcerative colitis (UC) and Crohn's disease (CD). Glucocorticoids (GCs) are the most effective treatment for moderate to severe active UC. However, one-third of patients are not sensitive to GCs (i.e., they are GC resistant). The mechanism of GC resistance in IBD is unknown, and it remains unclear how to predict resistance in IBD patients. This study aimed to explore the possible correlation between miRNA expression and variability in GC-resistant and GC-sensitive patients with ulcerative colitis. A comparative serum microRNA analysis in GC-resistant and GC-sensitive patients with ulcerative colitis was conducted by microarray. Differential microRNA expression was further validated in serum samples by quantitative real-time PCR. We found that downregulated microRNAs had a significant correlation with several signal transduction pathways (the PI3K-Akt and MAPK signaling pathways) and target genes (HSP90B1, MAPK13, MAPK9, PIK3AP1 and TLR4) related to GC resistance. Eight downregulated microRNAs were chosen for further validation in 76 serum samples. The results showed that miR-16-2-3p, miR-30e-3p, miR-32-5p, miR-642a-5p, miR-150-5p, and miR-224-5p were significantly downregulated in the GC-resistant group. Receiver operating characteristic analysis showed that the area under the curves (AUCs) for those microRNAs were 0.94, 0.93, 0.85, 0.87, 0.92, and 0.99, with specificities of 97.30%, 89.20%, 59.50%, 73.00%, 97.30%, and 97.30% and sensitivities of 74.40%, 84.60%, 97.40%, 92.30%, 66.70%, and 89.70%, respectively. Our study provides preliminary evidence for the pathogenic mechanism of GC resistance and shows that serum microRNAs might serve as biomarkers for GC resistance in IBD.

Antibiotics exposure and risk of inflammatory bowel disease: a systematic review

AIM

The aim of this study was to critically assess all available evidence suggesting an association between antibiotic exposure and new onset of inflammatory bowel disease (IBD).

MATERIALS AND METHODS

This systematic review was conducted according to the PRISMA statement and eligible studies were identified through search of PubMed, Embase and the Cochrane Library. Data on patient demographics, antibiotic exposure and confounding factors were analyzed. The Newcastle-Ottawa Scale (NOS) was used to assess the quality of eligible studies.

RESULTS

A total of 15 observational studies (10 case control and five cohort) including 8748 patients diagnosed with IBD were systematically reviewed. Antibiotic exposure was mostly associated with Crohn's disease but not with ulcerative colitis. In particular, penicillin's, cephalosporins, metronidazole and fluoroquinolones were most commonly associated with the onset of Crohn's disease. The impact of tetracycline-family antibiotics on the pathogenesis of IBD was not clear.

CONCLUSION

There may be an association between antibiotic exposure and the development of IBD; especially Crohn's disease. Even though, clinicians should be cautious when prescribing certain antibiotic regimens to patients with a strong family history of IBD, it should be emphasized that available data are not granular enough to reach any definitive conclusions.

Effect of oral tobacco use and smoking on outcomes of Crohn's disease in India

BACKGROUND AND AIM

Smoking has been linked with adverse outcomes in Crohn's disease (CD); however, it is not known whether oral tobacco (OT) use affects disease outcomes in these patients. The study aimed to assess the association between smoking or OT and outcomes in CD.

METHODS

Retrospective analysis was performed on prospectively maintained records of CD patients from 2004 to 2016. The parameters assessed included disease characteristics at baseline (location, behavior, age at onset, perianal disease, and extraintestinal manifestations), course pattern, and outcomes (surgery, hospitalizations, immunomodulator or biologics use, and steroid requirement).

RESULTS

A total of 426 patients were included (mean age: 39.9 years; 59.9% men; median follow up: 71 months). Forty patients were ever-OT users, and 59 were ever-smokers, ever-use being defined as daily use for at least 2 years. OT use was associated with male sex and smoking. Both OT use and smoking had no effect on baseline characteristics, but upper gastrointestinal disease was less common in ever-smokers. Both OT use and smoking did not have any effect on surgery, immunomodulator, and biologic use. Similarly, no association was found between these outcomes and duration, daily, and cumulative exposure to tobacco. Current but not former tobacco use in both smoked (adjusted odds ratio = 2.59 [1.22-5.49]) and OT (adjusted odds ratio = 2.97 [1.03-8.6]) forms increased risk of hospitalizations.

CONCLUSION

Oral tobacco use and smoking had no significant detrimental effect on disease phenotype or medical and surgical requirements in CD in Indian patients, affirming other non-Caucasian studies that found lack of effect of smoking. However, current tobacco use in any form was associated with hospitalization during follow up.

Chronic Inflammatory Diseases and Green Tea Polyphenols

Chronic inflammatory diseases affect millions of people globally and the incidence rate is on the rise. While inflammation contributes to the tissue healing process, chronic inflammation can lead to life-long debilitation and loss of tissue function and organ failure. Chronic inflammatory diseases include hepatic, gastrointestinal and neurodegenerative complications which can lead to malignancy. Despite the millennial advancements in diagnostic and therapeutic modalities, there remains no effective cure for patients who suffer from inflammatory diseases. Therefore, patients seek alternatives and complementary agents as adjunct therapies to relieve symptoms and possibly to prevent consequences of inflammation. It is well known that green tea polyphenols (GrTPs) are potent antioxidants with important roles in regulating vital signaling pathways. These comprise transcription nuclear factor-kappa B mediated I kappa B kinase complex pathways, programmed cell death pathways like caspases and B-cell lymphoma-2 and intervention with the surge of inflammatory markers like cytokines and production ofcyclooxygenase-2. This paper concisely reviews relevant investigations regarding protective effects of GrTPs and some reported adverse effects, as well as possible applications for GrTPs in the treatment of chronic and inflammatory complications.

Understanding and Preventing the Global Increase of Inflammatory Bowel Disease

The inflammatory bowel diseases (IBDs) are contemporary conditions of industrialized societies. The prevalence of IBD continues to increase steadily in Western countries, and newly industrialized countries have a rapidly increasing incidence. The global spread of IBD appears to associate with Westernization of diets and environments, which affects the intestinal microbiome and increases the risk of IBD in genetically susceptible individuals. It is important to increase our understanding of these events to slow progression of IBD. We present a long-term plan to develop interventions that slow or stop the global increase in the incidence of IBD.

Smoking influences the need for surgery in patients with the inflammatory bowel diseases: a systematic review and meta-analysis incorporating disease duration

Background

Studies examining the association between smoking and the need for surgery in patients with Crohn’s disease and ulcerative colitis have reached inconsistent conclusions. These studies often do not differentiate between patients undergoing early surgery and patients having surgery later in their disease course. Our study examined the association between smoking status and time to first bowel resection in patients with Crohn’s disease and ulcerative colitis.

Methods

We searched MEDLINE and EMBASE for studies (n = 12) reporting on the association between smoking status (current, former, and never) and surgery in IBD, and incorporated disease duration in the analysis. Hazard ratios (HR) with 95% confidence intervals (CI) were pooled across studies using random effects models.

Results

Current smokers with Crohn’s disease were at increased risk of intestinal resection compared to never smokers (HR 1.27, 95% CI 1.08 to 1.49); however, there was no difference in the need for surgery when comparing former and never smokers (HR 1.11, 95% CI 0.95 to 1.30). In patients with ulcerative colitis, there was no difference in the need for colectomy when comparing current smokers to never smokers (HR 0.98, 95% CI 0.67 to 1.44). Former smokers with ulcerative colitis were at increased risk of colectomy (HR 1.38, 95% CI 1.04 to 1.83) compared to never smokers.

Conclusions

Current smokers with Crohn’s disease are at increased risk of surgery, while former smokers with ulcerative colitis have increased risk of colectomy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-016-0555-8) contains supplementary material, which is available to authorized users.

Globalisation of inflammatory bowel disease: perspectives from the evolution of inflammatory bowel disease in the UK and China

The UK and China provide unique historical perspectives on the evolution of the incidence of inflammatory bowel disease, which might provide insight into its pathogenesis. Historical records from the UK document the emergence of ulcerative colitis during the mid-1800s, which was later followed by the recognition of Crohn's disease in 1932. During the second half of the 20th century, the incidence of inflammatory bowel disease rose dramatically in high-income countries. Globalisation at the turn of the 21st century led to rapid economic development of newly industrialised countries such as China. In China, the modernisation of society was accompanied by the recognition of a sharp rise in the incidence of inflammatory bowel disease. The prevalence of inflammatory bowel disease is expected to continue to rise in high-income countries and is also likely to accelerate in the developing world. An understanding of the shared and different environmental determinants underpinning the pathogenesis of inflammatory bowel disease in western and eastern countries is essential to implement interventions that will blunt the rising global burden of inflammatory bowel disease.