Beverage consumption and risk of ulcerative colitis: Systematic review and meta-analysis of epidemiological studies

Genetically Predicted Higher Levels of Caffeic Acid Are Protective Against Ulcerative Colitis: A Comprehensive Metabolome Analysis

BACKGROUND

It is crucial to pinpoint the metabolites that cause Crohn's disease (CD) and ulcerative colitis (UC) to comprehend their pathogenesis and identify possible targets for therapy. To achieve this goal, we performed the first metabolome-wide Mendelian randomization (MR) study of Japanese patients with CD and UC.

METHODS

As exposure datasets, genetic instruments with blood-circulating metabolites were obtained from the Tohoku Medical Megabank Organization, which includes 204 metabolites from the genome-wide association study data of 7843 Japanese individuals. As outcome datasets, we enrolled Japanese patients with CD (n = 1803), Japanese patients with UC (n = 1992), and healthy controls (n = 2022). The main analysis utilized the inverse variance-weighted method, while stability of the findings was evaluated through sensitivity analyses.

RESULTS

After single nucleotide polymorphism (SNP) filtering, 169 SNPs for 45 metabolites were available for MR. Genetically predicted elevated circulating trans-glutaconic acid and tryptophan were associated with a lower CD risk (odds ratio [OR], 0.68; P = 5.95 × 10-3; and OR, 0.64; P = 1.90 × 10-2, respectively). Genetically predicted elevated caffeic acid was associated with a lower UC risk (OR, 0.67; P = 4.2 × 10-4), which remained significant after multiple testing correction. We identified a causal link between UC and 3-hydroxybutyrate (OR, 2.21; P = 1.41 × 10-2), trans-glutaconic acid (OR, 0.72; P = 1.77 × 10-2), and 2-hydroxyvaleric acid (OR, 1.31; P = 4.23 × 10-2). There was no evidence of pleiotropy or reverse causal effects for these candidate metabolites.

CONCLUSIONS

In our metabolome-wide MR study, we discovered a notable protective effect of caffeic acid against UC.

How the Western Diet Thwarts the Epigenetic Efforts of Gut Microbes in Ulcerative Colitis and Its Association with Colorectal Cancer

Ulcerative colitis (UC) is an autoimmune disease in which the immune system attacks the colon, leading to ulcer development, loss of colon function, and bloody diarrhea. The human gut ecosystem consists of almost 2000 different species of bacteria, forming a bioreactor fueled by dietary micronutrients to produce bioreactive compounds, which are absorbed by our body and signal to distant organs. Studies have shown that the Western diet, with fewer short-chain fatty acids (SCFAs), can alter the gut microbiome composition and cause the host's epigenetic reprogramming. Additionally, overproduction of H2S from the gut microbiome due to changes in diet patterns can further activate pro-inflammatory signaling pathways in UC. This review discusses how the Western diet affects the microbiome's function and alters the host's physiological homeostasis and susceptibility to UC. This article also covers the epidemiology, prognosis, pathophysiology, and current treatment strategies for UC, and how they are linked to colorectal cancer.

Polyphenols from Foxtail Millet Improve Non-Alcoholic Fatty Liver Disease by Regulating Intestinal Microbiome in Mice

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic hepatic manifestation of metabolic dysfunction for which effective interventions are lacking. The burden of NAFLD is increasing at an alarming rate. NAFLD is frequently associated with morbidities such as dyslipidemia, type 2 diabetes mellitus and obesity, etc. The current study explored the potential role of bound polyphenols from foxtail millet (BPIS) in treating mice with NAFLD induced by a high-fat diet (HFD). The results indicated the critical role of BPIS in treating NAFLD by effectively restoring the gut microbiota in C57BL/6 mice that received a high-fat diet (HFD) for 12 weeks. At the same time, 16S rRNA analysis demonstrated that BPIS remodeled the overall structure of the gut microbiota from fatty liver diseases towards that of normal counterparts, including ten phylum and twenty genus levels. Further study found that the expression of tight junction proteins was upregulated in the BPIS-treated group. This study provides new insights into the potential NAFLD protective effects induced by polyphenols of foxtail millet.

Coffee and caffeine intake reduces risk of ulcerative colitis: a case-control study in Japan

BACKGROUND AND AIM

Although diet is one of the potential environmental factors affecting ulcerative colitis (UC), evidence is not sufficient to draw definitive conclusions. This Japanese case-control study examined the association between the consumption of coffee, other caffeine-containing beverages and food, and total caffeine and the risk of UC.

METHODS

The study involved 384 UC cases and 665 control subjects. Intake of coffee, decaffeinated coffee, black tea, green tea, oolong tea, carbonated soft drinks, and chocolate snacks was measured with a semiquantitative food-frequency questionnaire. Adjustments were made for sex, age, pack-years of smoking, alcohol consumption, history of appendicitis, family history of UC, education level, body mass index, and intake of vitamin C, retinol, and total energy.

RESULTS

Higher consumption of coffee and carbonated soft drinks was associated with a reduced risk of UC with a significant dose-response relationship (P for trend for coffee and carbonated soft drinks were <0.0001 and 0.01, respectively), whereas higher consumption of chocolate snacks was significantly associated with an increased risk of UC. No association was observed between consumption of decaffeinated coffee, black tea, green tea, or oolong tea and the risk of UC. Total caffeine intake was inversely associated with the risk of UC; the adjusted odds ratio between extreme quartiles was 0.44 (95% confidence interval: 0.29-0.67; P for trend <0.0001).

CONCLUSIONS

We confirmed that intake of coffee and caffeine is also associated with a reduced risk of UC in Japan where people consume relatively low quantities of coffee compared with Western countries.

The Role of the Microbiome in the Pathogenesis and Treatment of Ulcerative Colitis-A Literature Review

Ulcerative colitis (UC) is a chronic inflammatory bowel disease affecting the colon and rectum. UC's pathogenesis involves colonic epithelial cell abnormalities and mucosal barrier dysfunction, leading to recurrent mucosal inflammation. The purpose of the article is to show the complex interplay between ulcerative colitis and the microbiome. The literature search was conducted using the PubMed database. After a screening process of studies published before October 2023, a total of 136 articles were selected. It has been discovered that there is a fundamental correlation of a robust intestinal microbiota and the preservation of gastrointestinal health. Dysbiosis poses a grave risk to the host organism. It renders the host susceptible to infections and has been linked to the pathogenesis of chronic diseases, with particular relevance to conditions such as ulcerative colitis. Current therapeutic strategies for UC involve medications such as aminosalicylic acids, glucocorticoids, and immunosuppressive agents, although recent breakthroughs in monoclonal antibody therapies have significantly improved UC treatment. Furthermore, modulating the gut microbiome with specific compounds and probiotics holds potential for inflammation reduction, while fecal microbiota transplantation shows promise for alleviating UC symptoms. This review provides an overview of the gut microbiome's role in UC pathogenesis and treatment, emphasizing areas for further research.

Role of Diet-Microbiome Interaction in Gastrointestinal Disorders and Strategies to Modulate Them with Microbiome-Targeted Therapies

Diet is an important determinant of health and consequently is often implicated in the development of disease, particularly gastrointestinal (GI) diseases, given the high prevalence of meal-related symptoms. The mechanisms underlying diet-driven pathophysiology are not well understood, but recent studies suggest that gut microbiota may mediate the effect of diet on GI physiology. In this review, we focus primarily on two distinct GI diseases where the role of diet has been best studied: irritable bowel syndrome and inflammatory bowel disease. We discuss how the concurrent and sequential utilization of dietary nutrients by the host and gut microbiota determines the eventual bioactive metabolite profiles in the gut and the biological effect of these metabolites on GI physiology. We highlight several concepts that can be gleaned from these findings, such as how distinct effects of an individual metabolite can influence diverse GI diseases, the effect of similar dietary interventions on multiple disease states, and the need for extensive phenotyping and data collection to help make personalized diet recommendations.

The adverse and beneficial effects of polyphenols in green and black teas in vitro and in vivo

Although numerous studies highlight the health benefits of tea, excessive consumption has been linked to toxic conditions. Thus, understanding the optimal consumption of tea is essential to minimize toxicity while maximizing its benefits. In this study, we investigated the effects of eight green tea samples (G1-G8) and eight black tea samples (R1-R8) from Camellia sinensis, the most popular teas in Asian culture, on RSC96 Schwann neural cells and embryonic cardiomyocyte H9c2 cells. The results showed that the IC50 (mg/ml, weight/volume) of both tea types were inversely proportional to their polyphenol content, suggesting a relationship between toxicity and polyphenol levels in both green and black tea. Interestingly, green teas generally have higher polyphenol content than black teas. We also assessed the protective effects of tea in vitro by pretreating cells with the teas at indicated doses of polyphenol and subsequently exposing them to H2O2. Both tea types significantly reduced the decline in cell viability for both cell lines, and there was no significant difference in protective polyphenol concentrations for green (G3 & G7) and black (R3 & R8) teas at effective concentrations (EC20 and EC40). To evaluate the preventative effects of tea in vivo, we examined the impact of two green (G3 & G7) and two black (R3 & R8) teas with varying polyphenol content on dextran sulfate sodium (DSS)-induced inflammatory colitis in mice. Tea-treated groups exhibited significantly lower inflammatory scores (DAI) than the control group. DSS treatment in the control group led to shortened colorectal lengths in mice, while tea co-treatment partially prevented this loss. Histological analysis revealed that G7 and R3 (with a moderate polyphenol content) treatment improved colorectal crypt structure, decreased the severity of inflammatory ulcerative colitis, and significantly reduced histological scores compared to the control group. However, G3 and R8 (with high and low doses of polyphenol content, respectively) did not show these effects, suggesting that a moderate polyphenol level in both tea types is optimal for preventative benefits.

Sugar-sweetened beverages exacerbate high-fat diet-induced inflammatory bowel disease by altering the gut microbiome

High-fat diets (HFDs) and frequent consumption of sugar-sweetened beverages (SSBs) are potential contributors to increasing inflammatory bowel disease (IBD) incidences. While HFDs have been implicated in mild intestinal inflammation, the role of sucrose in SSBs remains unclear. Therefore, we studied the role of SSBs in IBD pathogenesis in a mouse model and humans. C57BL6/J mice were given ad libitum access to a sucrose solution or plain water for 10 weeks, with or without an HFD. Interestingly, sucrose solution consumption alone did not induce gut inflammation in mice; however, when combined with an HFD, it dramatically increased the inflammation score, submucosal edema, and CD45⁺ cell infiltration. 16S ribosomal RNA gene-sequencing revealed that sucrose solution and HFD co-consumption significantly increased the relative abundance of IBD-related pathogenic bacteria when compared with HFD consumption. RNA sequencing and flow cytometry showed that co-consumption promoted pro-inflammatory cytokine and chemokine synthesis, dendritic-cell expansion, and IFN-γ⁺TNF-α⁺CD4⁺ and CD8⁺ T-cell activation. Fecal microbiota transplantation from HFD- and sucrose water-fed mice into gut-sterilized mice increased the susceptibility to dextran sulfate sodium-induced colitis in the recipient mice. Consistent herewith, high consumption of SSBs and animal fat-rich diets markedly increased systemic inflammation-associated IBD marker expression in humans. In conclusion, SSBs exacerbate HFD-induced colitis by triggering a shift of the gut microbiome into a pathobiome. Our findings provide new insights for the development of strategies aimed at preventing IBD.

A Mendelian Randomization Analysis Investigates Causal Associations between Inflammatory Bowel Diseases and Variable Risk Factors

The question of whether variable risk factors and various nutrients are causally related to inflammatory bowel diseases (IBDs) has remained unanswered so far. Thus, this study investigated whether genetically predicted risk factors and nutrients play a function in the occurrence of inflammatory bowel diseases, including ulcerative colitis (UC), non-infective colitis (NIC), and Crohn's disease (CD), using Mendelian randomization (MR) analysis. Utilizing the data of genome-wide association studies (GWASs) with 37 exposure factors, we ran Mendelian randomization analyses based on up to 458,109 participants. Univariable and multivariable MR analyses were conducted to determine causal risk factors for IBD diseases. Genetic predisposition to smoking and appendectomy as well as vegetable and fruit intake, breastfeeding, n-3 PUFAs, n-6 PUFAs, vitamin D, total cholesterol, whole-body fat mass, and physical activity were related to the risk of UC (p < 0.05). The effect of lifestyle behaviors on UC was attenuated after correcting for appendectomy. Genetically driven smoking, alcohol consumption, appendectomy, tonsillectomy, blood calcium, tea intake, autoimmune diseases, type 2 diabetes, cesarean delivery, vitamin D deficiency, and antibiotic exposure increased the risk of CD (p < 0.05), while vegetable and fruit intake, breastfeeding, physical activity, blood zinc, and n-3 PUFAs decreased the risk of CD (p < 0.05). Appendectomy, antibiotics, physical activity, blood zinc, n-3 PUFAs, and vegetable fruit intake remained significant predictors in multivariable MR (p < 0.05). Besides smoking, breastfeeding, alcoholic drinks, vegetable and fruit intake, vitamin D, appendectomy, and n-3 PUFAs were associated with NIC (p < 0.05). Smoking, alcoholic drinks, vegetable and fruit intake, vitamin D, appendectomy, and n-3 PUFAs remained significant predictors in multivariable MR (p < 0.05). Our results provide new and comprehensive evidence demonstrating that there are approving causal effects of various risk factors on IBDs. These findings also supply some suggestions for the treatment and prevention of these diseases.

In Situ Interfacial Super-Assembly of Nanobiohybrids through Plant for Food-Grade Oral Medicine

Developing a next-generation oral drug delivery system with enhanced efficacy and limited side effects is highly desired for refractory diseases treatment such as colitis. The bioinspired assembly of drugs within food-grade plants highlights its potential value of this unique hybrid material. Herein, we report the preparation of drug-encapsulated vegetable nanobiohybrid superassembled frameworks as an oral food-grade drug delivery system (SAF-FGDD). The in situ superassembly of SAF-FGDD driven by natural transpiration from living plants is carried out through a sustainable and low-carbon manner, allowing for the assembly of distinct precursors inside edible living plants. As an example, mesalazine, an anti-inflammatory drug, is encapsulated in the frameworks for colitis treatment. The cell activity and feeding experiments of zebrafish and mice demonstrate the excellent efficacy of this SAF-FGDD. Compared with those of the control groups, the disease activity index scores and histological scores of the SAF-FGDD group were significantly decreased by 80% and 98%, respectively. The improved performance is attributed to the biocompatibility and protective effect of SAF-FGDD, allowing for abundant mesalazine to be released and act at the site of the intestine during the process of food digestion. In combination with mature soilless cultivation technology, plant-based organisms with natural structure-forming abilities possess broad commercial prospects in large-scale production of various food-grade functional materials.

Nutrition in inflammatory bowel diseases; Is there a role?

Nutrition is of paramount importance not only for healthy individuals, but all the more for the ones with pathologies interlinked with the diet. In that light, diet, when used accordingly can act in a protective manner in inflammatory bowel diseases. The interplay of diet and IBD is not thoroughly defined, and guidelines are a work in progress. However, significant knowledge has been gained with regard to foods and nutrients that may exacerbate or alleviate the core symptoms. Patients with IBD restrict from their diet a plethora of foods often arbitrary, thus depriving themselves from valuable constituents. Careful navigation into the newfound field of genetic variants and personalization of diet should be employed with avoidance of the Westernized diet, processed foods and additives, and focus on a holistic approach with a balanced diet rich in bioactive compounds in order to improve the quality of life of these patients and address diet-related deficiencies.

Gut Bacterial Indole-3-acetic Acid Induced Immune Promotion Mediates Preventive Effects of Fu Brick Tea Polyphenols on Experimental Colitis

Ulcerative colitis has been consistently associated with gut microbiota imbalance and disturbed immune system. Emerging research suggests a protective function of polyphenols on prevention and treatment of ulcerative colitis, yet underlying mechanisms remain unclear. Fu brick tea, a postfermented tea, contains abundant polyphenols with anti-inflammatory and antioxidant properties. In the present study, we found that prophylactic supplementation of polyphenols extracted from Fu brick tea (FBTP) dose-dependently alleviated colitis symptoms, immune cells infiltration, and pro-inflammatory cytokines secretion in mice suffering dextran sulfate sodium induced murine colitis. FBTP substantially reshaped gut microbiota and promoted microbial transformation of tryptophan into indole-3-acetic acid (I3A), thereafter leading to aryl hydrocarbon receptor (AHR)-mediated protection from colitis through enhanced expressions of IL-22 and tight junction proteins (i.e., ZO-1, occluding and claudin-1) in colon. Multiomics integration analyses revealed strong connections between I3A, tryptophan-metabolizing bacteria, AHR activity, and pathological phenotypes of colitis. Notably, FBTP failed to significantly alleviate colitis symptoms in the absence of gut microbiota, while intragastric administration of I3A could imitate benefits of FBTP on colitis alleviation and intestinal epithelial homeostasis through a direct enhancement in AHR activity in microbiota-depleted mice. These findings further determine the key role of gut microbiota controlled I3A-AHR signaling in mediating the FBTP on colitis alleviation. This study provides the first data proposing the FBTP as a natural prebiotic for colitis alleviation through the gut microbiota-dependent modulation of the AHR pathway. Most importantly, we also identified I3A as a key microbial metabolite targeted by FBTP for exhibiting health-promoting effects.

Polyphenols from foxtail millet bran ameliorate DSS-induced colitis by remodeling gut microbiome

INTRODUCTION

Polyphenols from plants possess the anti-inflammatory and gut microbiota modulated properties. Foxtail millet (Setaria italica L., FM) has potential medical and nutritional functions because of rich phenolic and other phytochemical components.

METHODS

Here, the study explored the effects of bound polyphenol of inner shell (BPIS) from FM bran on dextran sodium sulfate (DSS)-induced experimental colitis mice.

RESULTS

Results showed that BPIS administration effectively relieved the weight loss, decreased disease active index (DAI) scores, restrained the secretion of pro-inflammatory cytokines TNF-α, IL-6 and IL-1β, increased anti-inflammatory cytokines IL-10, IL-4, IL-5. BPIS prevented gut barrier damage by enhancing tight junction proteins Claudin1, ZO-1 and Occludin, increasing the number of goblet cells and facilitating the gene expressions of mucin family. In addition, BPIS restored the gut microbiota composition and increased the relative abundance of commensal bacteria such as Lachnospiraceae and Rikenellaceae and restrained the growth of S24-7 and Staphylococcaceae. Concentrations of short-chain-fatty acids (SCFAs) generated by gut microbiota were elevated in BPIS treated colitis mice.

CONCLUSION

These data suggest that BPIS effectively ameliorates DSS-induced colitis by preventing intestinal barrier damage and promoting gut microbiota community.

Environmental risk factors for inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic, progressive immune-mediated inflammatory condition of the gastrointestinal tract. Environmental risk factors play a role in developing either type of IBD, Crohn's disease and ulcerative colitis; although the exact mechanism is still unknown. Herein, we review environmental risks from early life exposures, lifestyle and hygiene, vaccinations, surgeries, exposure to drugs and gastrointestinal pathogens that may increase the risk of developing IBD.

Association between ultra-processed food consumption and gut microbiota in senior subjects with overweight/obesity and metabolic syndrome

The production and consumption of ultra-processed foods (UPF) has increased considerably during the last years worldwide. Collective evidence shows the association between UPF consumption and adverse health outcomes, including inflammatory gastro-intestinal disorders and obesity. The gut microbiota has been suggested as potential mediator of the effects of UPF consumption on metabolism and health. However, few studies have been conducted in order to elucidate these aspects. Therefore, the aim of the present study was to assess the cross-sectional associations between UPF consumption and gut microbiota in a population of senior subjects (n = 645) within the frame of the PREDIMED-Plus trial. Eligible participants were men and women (aged 55-75 years), without documented history of cardiovascular disease at enrollment, with overweight/obesity (body mass index ≤ 27 and <40 kg/m²) and metabolic syndrome. Using the information of food frequency questionnaires, the consumption of UPF, expressed as a percentage of total dietary energy intake in kcal/day, was calculated considering those food items classified in group 4 of NOVA system. Population was categorized according to tertiles of UPF consumption. Taxonomic fecal microbiota information, along with blood biochemical parameters, anthropometric measurements and clinical data were obtained. Bioinformatics analysis was performed to study the association between fecal microbiota composition and UPF consumption. We observed that subjects allocated in the highest tertile of UPF consumption (21.4 ± 5.0 % kcal/day) presented lower adherence to MedDiet (p < 0.001) and higher total energy intake (p < 0.001). The taxonomic analysis of the fecal microbiota revealed a significant (Benjamini-Hochberg adjusted p < 0.2) positive association between specific taxa and tertiles (T) of UPF consumption: Alloprevotella (p = 0.041 vs. T2; p = 0.065 vs. T3), Negativibacillus (p = 0.096 vs. T3), Prevotella (p = 0.116 vs. T3), and Sutterella (p = 0.116 vs. T2). UPF consumption was positively associated with lower adherence to MedDiet and higher total energy intake in senior subjects with overweight obesity and metabolic syndrome. In addition, positive association with specific fecal microbiota taxa related to inflammatory gastro-intestinal diseases and low consumption of fruits and vegetables, was observed.

Dietary Patterns and Gut Microbiota Changes in Inflammatory Bowel Disease: Current Insights and Future Challenges

Inflammatory bowel disease (IBD) is a result of a complex interplay between genes, host immune response, gut microbiota, and environmental factors. As one of the crucial environmental factors, diet plays a pivotal role in the modulation of gut microbiota community and the development of IBD. In this review, we present an overview of dietary patterns involved in the pathogenesis and management of IBD, and analyze the associated gut microbial alterations. A Westernized diet rich in protein, fats and refined carbohydrates tends to cause dysbiosis and promote IBD progression. Some dietary patterns have been found effective in obtaining IBD clinical remission, including Crohn's Disease Exclusion Diet (CDED), Mediterranean diet (MD), Anti-Inflammatory Diet (AID), the low-"Fermentable Oligo-, Di-, Mono-saccharides and Polyols" (FODMAP) diet, Specific Carbohydrate Diet (SCD), and plant-based diet, etc. Overall, many researchers have reported the role of diet in regulating gut microbiota and the IBD disease course. However, more prospective studies are required to achieve consistent and solid conclusions in the future. This review provides some recommendations for studies exploring novel and potential dietary strategies that prevent IBD.

Sugar-sweetened beverages, artificially sweetened beverages and natural juices and risk of inflammatory bowel disease: a cohort study of 121,490 participants

BACKGROUND

Inflammatory bowel diseases (IBD) have been related to high-sugar dietary patterns, but the associations of different types of beverages with IBD risk are largely unknown.

AIMS

To examine any associations between intake of sugar-sweetened beverages, artificially sweetened beverages and natural juices and IBD risk METHODS: This cohort study included 121,490 participants in the UK Biobank who were free of IBD at recruitment. Intake of beverages was obtained from repeated 24-h diet recalls in 2009-2012. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for associations of beverage intake with IBD risk.

RESULTS

During a mean (standard deviation) follow-up of 10.2 (1.5) years, we documented 510 incident IBD cases, (143 Crohn's disease (CD) and 367 ulcerative colitis (UC)). Compared to non-consumers, participants consuming >1 unit per day of sugar-sweetened beverages were at significantly higher risk of IBD (HR 1.51, 95% CI 1.11-2.05), but the trend was non-significant (p-trend = 0.170). This association was significant for CD (HR 2.05, 95% CI 1.22-3.46), but not for UC (HR 1.31, 95% CI 0.89-1.92). We did not observe significant associations for the consumption of artificially sweetened beverages or natural juices.

CONCLUSIONS

Our findings suggest an association between consumption of sugar-sweetened beverages, rather than artificially sweetened beverages or natural juices, and IBD risk.

Evidence-based pathogenesis and treatment of ulcerative colitis: A causal role for colonic epithelial hydrogen peroxide

In this comprehensive evidence-based analysis of ulcerative colitis (UC), a causal role is identified for colonic epithelial hydrogen peroxide (H₂O₂) in both the pathogenesis and relapse of this debilitating inflammatory bowel disease. Studies have shown that H₂O₂ production is significantly increased in the non-inflamed colonic epithelium of individuals with UC. H₂O₂ is a powerful neutrophilic chemotactic agent that can diffuse through colonic epithelial cell membranes creating an interstitial chemotactic molecular “trail” that attracts adjacent intravascular neutrophils into the colonic epithelium leading to mucosal inflammation and UC. A novel therapy aimed at removing the inappropriate H₂O₂ mediated chemotactic signal has been highly effective in achieving complete histologic resolution of colitis in patients experiencing refractory disease with at least one (biopsy-proven) histologic remission lasting 14 years to date. The evidence implies that therapeutic intervention to prevent the re-establishment of a pathologic H₂O₂ mediated chemotactic signaling gradient will indefinitely preclude neutrophilic migration into the colonic epithelium constituting a functional cure for this disease. Cumulative data indicate that individuals with UC have normal immune systems and current treatment guidelines calling for the suppression of the immune response based on the belief that UC is caused by an underlying immune dysfunction are not supported by the evidence and may cause serious adverse effects. It is the aim of this paper to present experimental and clinical evidence that identifies H₂O₂ produced by the colonic epithelium as the causal agent in the pathogenesis of UC. A detailed explanation of a novel therapeutic intervention to normalize colonic H₂O₂, its rationale, components, and formulation is also provided.

Inflammatory auto-immune diseases of the intestine and their management by natural bioactive compounds

Autoimmune diseases are caused by the overactivity of the immune system towards self-constituents. Risk factors of autoimmune diseases are multiple and include genetic, epigenetic, environmental, and psychological. Autoimmune chronic inflammatory bowel diseases, including celiac and inflammatory diseases (Crohn's disease and ulcerative colitis), constitute a significant health problem worldwide. Besides the complexity of the symptoms of these diseases, their treatments have only been palliative. Numerous investigations showed that natural phytochemicals could be promising strategies to fight against these autoimmune diseases. In this respect, plant-derived natural compounds such as flavonoids, phenolic acids, and terpenoids exhibited significant effects against three autoimmune diseases affecting the intestine, particularly bowel diseases. This review focuses on the role of natural compounds obtained from medicinal plants in modulating inflammatory auto-immune diseases of the intestine. It covers the most recent literature related to the effect of these natural compounds in the treatment and prevention of auto-immune diseases of the intestine.

Efficacy of Probiotics-Based Interventions as Therapy for Inflammatory Bowel Disease: A Recent Update

Probiotics such as Lactobacillus spp. play an important role in human health as they embark beneficial effect on the human gastrointestinal microflora composition and immune system. Dysbiosis in the gastrointestinal microbial composition has been identified as a major contributor to chronic inflammatory conditions, such as inflammatory bowel disease (IBD). Higher prevalence of IBD is often recorded in most of the developed Western countries, but recent data has shown an increase in previously regarded as lower risk regions, such as Japan, Malaysia, Singapore, and India. Although the IBD etiology remains a subject of speculation, the disease is likely to have developed because of interaction between extrinsic environmental elements; the host’s immune system, and the gut microbial composition. Compared to conventional treatments, probiotics and probiotic-based interventions including the introduction of specific prebiotics, symbiotic and postbiotic products had been demonstrated as more promising therapeutic measures. The present review discusses the association between gut dysbiosis, the pathogenesis of IBD, and risk factors leading to gut dysbiosis. In addition, it discusses recent studies focused on the alteration of the gastrointestinal microbiome as an effective therapy for IBD. The impact of the COVID-19 pandemic and other viral infections on IBD are also discussed in this review. Clinical and animal-based studies have shown that probiotic-based therapies can restore the gastrointestinal microbiota balance and reduce gut inflammations. Therefore, this review also assesses the status quo of these microbial-based therapies for the treatment of IBD. A better understanding of the mechanisms of their actions on modulating altered gut microbiota is required to enhance the effectiveness of the IBD therapeutics.

Beverage Consumption and Ulcerative Colitis: A Case-Control Study from Saudi Arabia

Background: The association between beverage intake and ulcerative colitis (UC) is not well-established, with no available data from Arab countries. Herein, we investigated the potential association of consuming coffee, tea, and carbonated soft drinks with UC among a population from Saudi Arabia. Methods: This hospital-based case-control study used data of 171 newly diagnosed UC patients and 400 patients with other gastrointestinal conditions who served as controls. All UC cases were ascertained by endoscopy, while beverage intake was assessed by a questionnaire that was completed before diagnosis. We computed odds ratios (ORs) and 95% confidence intervals (95% CIs) of UC and UC extension for frequent versus infrequent intakes of coffee, tea, and carbonated soft drinks using logistic regression. Results: Overall, 23.4% of UC patients had pancolitis, 21.1% extensive, 51.4% left-sided, and 4.1% proctitis. UC patients had a similar sex distribution to the controls but were older and had a lower BMI. After adjustment for age, sex, body mass index, and smoking history, frequent intakes of coffee and tea were associated with lower odds of UC: 0.62 (0.42, 0.91) and 0.53 (0.35, 0.79), respectively. On the other hand, frequent intakes of carbonated soft drinks were associated with increased odds of UC: 9.82 (6.12, 15.76). The frequency of beverage consumption was not associated with UC extension. Conclusion: UC was negatively associated with frequent coffee and tea consumption but positively associated with frequent carbonated soft drink intake in Saudi people. More population-based prospective cohort studies are needed to confirm our findings.

Western and Carnivorous Dietary Patterns are Associated with Greater Likelihood of IBD Development in a Large Prospective Population-based Cohort

OBJECTIVE

Nutrition plays a role in the development of Crohn's disease [CD] and ulcerative colitis [UC]. However, prospective data on nutrition and disease onset are limited. Here, we analysed dietary patterns and scores in relation to inflammatory bowel disease [IBD] development in a prospective population-based cohort.

METHODS

We analysed 125 445 participants of whom 224 individuals developed de novo UC and 97 CD over a maximum 14-year follow-up period. Participants answered health-related [also prospectively] and dietary questionnaires [FFQ] at baseline. Principal component analysis [PCA] was conducted deriving a-posteriori dietary patterns. Hypotheses-based a-priori dietary scores were also calculated, including the protein score, Healthy Eating Index, LifeLines Diet Score [LLDS], and alternative Mediterranean Diet Score. Logistic regression models were performed between dietary patterns, scores, and IBD development.

RESULTS

PCA identified five dietary patterns. A pattern characterised by high intake of snacks, prepared meals, non-alcoholic beverages, and sauces along with low vegetables and fruit consumption was associated with higher likelihood of CD development (odds ratio [OR]: 1.16, 95% confidence interval [CI]: 1.03-1.30, p = 0.013). A pattern comprising red meat, poultry, and processed meat, was associated with increased likelihood of UC development [OR: 1.11, 95% CI: 1.01-1.20, p = 0.023]. A high diet quality score [LLDS] was associated with decreased risk of CD [OR: 0.95, 95% CI: 0.92-0.99, p = 0.009].

CONCLUSIONS

A Western dietary pattern was associated with a greater likelihood of CD development and a carnivorous pattern with UC development, whereas a relatively high diet quality [LLDS] was protective for CD development. Our study strengthens the importance of evaluating dietary patterns to aid prevention of IBD in the general population.

Dietary Intake of Total Carbohydrates, Sugar and Sugar-Sweetened Beverages, and Risk of Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

Objectives: No earlier study has summarized findings from prospective cohort studies on the association of dietary carbohydrates, sugar, and sugar-sweetened beverages (SSBs) consumption and risk of inflammatory bowel disease (IBD). The current study was done to quantitatively summarize earlier information from prospective cohort studies on the link between dietary carbohydrates, sugar, and SSBs intake with risk of IBD.

Methods: Relevant studies published up to June 2021 were searched through PubMed, Medline, SCOPUS, EMBASE, and Google Scholar with the use of relevant keywords. All prospective cohort studies investigating the association of dietary carbohydrates, sugar, and SSBs consumption with risk of IBD were included.

Results: Combining 5 effect sizes from 4 cohort studies, no significant association was found between dietary intake of carbohydrates and risk of ulcerative colitis (UC) (RR: 1.22; 95% CI: 0.70–2.14). The same findings were obtained for risk of Crohn's disease (CD) (RR: 1.06; 95% CI: 0.64–1.75) based on 4 studies with 5 effect sizes. A significant positive association was observed between sugar intake and risk of UC (RR: 1.59; 95% CI: 1.15–2.20), as well as CD (RR: 1.90; 95% CI: 1.06–3.41) when 5 effect sizes from 4 cohort studies were combined. The overall effect size, based on 4 estimates, revealed no significant association between SSBs consumption and risk of UC (RR: 1.02; 95% CI: 0.92–1.12) and CD (RR: 1.22; 95% CI: 0.91–1.64).

Conclusions: Summarizing earlier studies, sugar intake was found to be associated with increased risk of IBD and its subtypes. Any significant association between dietary intake of carbohydrates and SSBs and risk of IBD and its subtypes was not found.

Emerging Comorbidities in Inflammatory Bowel Disease: Eating Disorders, Alcohol and Narcotics Misuse

Inflammatory bowel disease (IBD) is a chronic and potentially devastating condition of the digestive tract which is exemplified by increasing prevalence worldwide, byzantine pathogenesis with a poorly defined role of the environmental factors, and complex clinical demonstration. As a systemic disease, IBD may progress with a wide spectrum of extraintestinal manifestations (EMs) and comorbidities affecting different organs and systems, from anaemia, undernutrition, and cancer to those which are often neglected like anxiety and depression. Evolving IBD epidemiology and changing environment are reflected by an expanding list of IBD-related comorbidities. In contrast to the well-established role of smoking the connection between alcohol and IBD is still debatable on many levels, from pathogenesis to complications. Furthermore, little is known about narcotics use in IBD patients, even if there are obvious factors that may predispose them to narcotics as well as alcohol misuse. Last but not least, the question arises what is the prevalence of eating disorders in IBD. In our paper, we aimed to discuss the current knowledge on alcohol and drugs misuse and eating disorders as emerging extraintestinal comorbidities in IBD.

Gut microbiota from green tea polyphenol-dosed mice improves intestinal epithelial homeostasis and ameliorates experimental colitis

BACKGROUND

Alteration of the gut microbiota may contribute to the development of inflammatory bowel disease (IBD). Epigallocatechin-3-gallate (EGCG), a major bioactive constituent of green tea, is known to be beneficial in IBD alleviation. However, it is unclear whether the gut microbiota exerts an effect when EGCG attenuates IBD.

RESULTS

We first explored the effect of oral or rectal EGCG delivery on the DSS-induced murine colitis. Our results revealed that anti-inflammatory effect and colonic barrier integrity were enhanced by oral, but not rectal, EGCG. We observed a distinct EGCG-mediated alteration in the gut microbiome by increasing Akkermansia abundance and butyrate production. Next, we demonstrated that the EGCG pre-supplementation induced similar beneficial outcomes to oral EGCG administration. Prophylactic EGCG attenuated colitis and significantly enriched short-chain fatty acids (SCFAs)-producing bacteria such as Akkermansia and SCFAs production in DSS-induced mice. To validate these discoveries, we performed fecal microbiota transplantation (FMT) and sterile fecal filtrate (SFF) to inoculate DSS-treated mice. Microbiota from EGCG-dosed mice alleviated the colitis over microbiota from control mice and SFF shown by superiorly anti-inflammatory effect and colonic barrier integrity, and also enriched bacteria such as Akkermansia and SCFAs. Collectively, the attenuation of colitis by oral EGCG suggests an intimate involvement of SCFAs-producing bacteria Akkermansia, and SCFAs, which was further demonstrated by prophylaxis and FMT.

CONCLUSIONS

This study provides the first data indicating that oral EGCG ameliorated the colonic inflammation in a gut microbiota-dependent manner. Our findings provide novel insights into EGCG-mediated remission of IBD and EGCG as a potential modulator for gut microbiota to prevent and treat IBD. Video Abstract.

Systematic review with meta-analysis: dietary intake in adults with inflammatory bowel disease

BACKGROUND

Poor dietary intake is associated with the development of malnutrition, micronutrient deficiencies, anaemia and osteoporosis in individuals with inflammatory bowel disease. While trials are underway to manipulate the diet of people with IBD, there has been no comprehensive systematic review of the dietary intake of adults with IBD.

AIMS

To conduct a systematic evaluation and meta-analysis of the dietary intake of adults with IBD, including macronutrients, micronutrients and food group data.

METHODS

CINAHL, Embase, Medline and Scopus were searched from 1 January 2000 to 25 September 2020 for cohort, case-control or cross-sectional studies that reported usual dietary intake in adults. Data were pooled and reported as weighted mean intake for: all adults with IBD; Crohn's disease; ulcerative colitis; active disease; remission; males; females. A random-effects meta-analysis model compared intake with healthy individuals.

RESULTS

Forty studies were identified and 19 were included in the meta-analysis. All subgroups of adults with IBD consumed inadequate energy (mean intake in adults with IBD 1980 ± 130 kcal), fibre (14 ± 4 g), folate (246 ± 33 mg) and calcium (529 ± 114 mg) per day. Intake of breads and cereals, legumes, fruit, vegetables and dairy were inadequate. Compared to healthy individuals, adults with IBD consume significantly less dietary fibre (SMD -0.59; 95% CI: -0.73, -0.46).

CONCLUSIONS

This review provides improved clarity about the dietary intake of adults with IBD. Future attention is required to improve diet quality and increase understanding of factors influencing dietary intake in IBD.

Causal relationship from coffee consumption to diseases and mortality: a review of observational and Mendelian randomization studies including cardiometabolic diseases, cancer, gallstones and other diseases

PURPOSE

High coffee consumption is associated with low risk of mortality and morbidity, but the causality remains unclear. This review aims to discuss findings from observational studies on coffee consumption in context of Mendelian randomization studies.

METHODS

The PubMed database was searched for all Mendelian randomization studies on coffee consumption and corresponding observational studies.

RESULTS

High coffee consumption is associated with low risk of all-cause and cardiovascular mortality in observational studies (HRs of 0.85-0.90 vs. no/low consumers), with no support of causality in Mendelian randomization studies. Moderate/high consumption is associated with low risk of cardiometabolic diseases, including ischemic heart disease (HRs of 0.85-0.90 vs. no/low consumption), stroke (HRs of approximately 0.80 vs. no/low consumption), type 2 diabetes (HRs of approximately 0.70 vs. no/low consumption) and obesity in observational studies, but not in Mendelian randomization studies. High consumption is associated with low risk of endometrial cancer and melanoma and high risk of lung cancer in observational studies, but with high risk of colorectal cancer in Mendelian randomization studies. In observational and Mendelian randomization studies, high coffee consumption is associated with low risk of gallstones (HRs of 0.55-0.70 for high vs. no/low self-reported and 0.81 (0.69-0.96) for highest vs. lowest genetic consumption).

CONCLUSION

High coffee consumption is associated with low risk of mortality, cardiometabolic diseases, some cancers and gallstones in observational studies, with no evidence to support causality from Mendelian randomization studies for most diseases except gallstones.

Food and Food Groups in Inflammatory Bowel Disease (IBD): The Design of the Groningen Anti-Inflammatory Diet (GrAID)

Diet plays a pivotal role in the onset and course of inflammatory bowel disease (IBD). Patients are keen to know what to eat to reduce symptoms and flares, but dietary guidelines are lacking. To advice patients, an overview of the current evidence on food (group) level is needed. This narrative review studies the effects of food (groups) on the onset and course of IBD and if not available the effects in healthy subjects or animal and in vitro IBD models. Based on this evidence the Groningen anti-inflammatory diet (GrAID) was designed and compared on food (group) level to other existing IBD diets. Although on several foods conflicting results were found, this review provides patients a good overview. Based on this evidence, the GrAID consists of lean meat, eggs, fish, plain dairy (such as milk, yoghurt, kefir and hard cheeses), fruit, vegetables, legumes, wheat, coffee, tea and honey. Red meat, other dairy products and sugar should be limited. Canned and processed foods, alcohol and sweetened beverages should be avoided. This comprehensive review focuses on anti-inflammatory properties of foods providing IBD patients with the best evidence on which foods they should eat or avoid to reduce flares. This was used to design the GrAID.

Cigarette Smoking, Coffee Consumption, Alcohol Intake, and Risk of Crohn's Disease and Ulcerative Colitis: A Mendelian Randomization Study

BACKGROUND

Crohn's disease (CD) and ulcerative colitis (UC) are widely associated with smoking in epidemiological studies, whereas there are conflicting results for the association between CD and UC for both coffee and alcohol consumption. Herein, we aimed to investigate whether cigarette smoking and alcohol and coffee consumption are causally associated with either CD or UC.

METHODS

We utilized 540 genome-wide significant single-nucleotide polymorphisms for 3 potentially addictive substances-nicotine, alcohol, and caffeine-to assess the association of smoking, coffee, and alcohol consumption with CD and UC (12,194 CD cases, 12,366 UC cases, and 25,042 controls of European ancestry), using Mendelian randomization analysis. Mendelian randomization estimates were used to evaluate the effect of the exposure factors on CD and UC risk. Sensitivity analysis was employed to test for any directional pleiotropy.

RESULTS

We found evidence for a positive causal association between the age of smoking initiation and UC risk and between alcohol consumption and CD risk, which disappeared after sensitivity analysis for both associations (P > 0.05). No evidence for a causal association between cigarettes per day, smoking initiation, smoking cessation, and coffee consumption variables and UC or CD was found.

CONCLUSIONS

We found no clear evidence that either genetically predicted smoking, coffee consumption, or alcohol consumption are causally associated with the risk for CD or UC, although our findings indicate a potential positive association between the age of smoking and UC and between alcohol consumption and CD.

Does Drinking Coffee and Tea Affect Bone Metabolism in Patients with Inflammatory Bowel Diseases?

Patients suffering from Crohn’s disease and ulcerative colitis are at higher risk of osteoporosis due to lower bone mineral density. Risk factors of osteoporosis are divided into unmodifiable, namely, age, gender, genetic factors, as well as modifiable, including diet, level of physical activity, and the use of stimulants. Coffee and tea contain numerous compounds affecting bone metabolism. Certain substances such as antioxidants may protect bones; other substances may increase bone resorption. Nevertheless, the influence of coffee and tea on the development and course of inflammatory bowel diseases is contradictory.

Identification of Environmental Risk Factors Associated With the Development of Inflammatory Bowel Disease

BACKGROUND AND AIMS

Multiple genetic and environmental factors are involved in the aetiology of inflammatory bowel disease [IBD] including Crohn's disease [CD] and ulcerative colitis [UC], but data on these exposome factors are difficult to identify. Several exposome factors such as smoking have been shown to be involved; as for other environmental factors, eg stress, results have been conflicting.

METHODS

We performed a case-control study including 674 IBD patients of the 1000IBD cohort, frequency-matched based on sex and age with 1348 controls from the population-based Lifelines Cohort Study. Exposome data were obtained using the validated Groningen IBD Environmental Questionnaire [GIEQ], capturing exposome factors through different stages of life using 844 items, of which 454 were applicable to study the role of 93 exposome factors in disease aetiology. Logistic regression [LR] modelling with Bonferroni correction for multiple testing was applied to estimate the multivariable-adjusted effect of each exposome factor.

RESULTS

For IBD, we identified four novel factors: stressful life events (CD odds ratio [OR] 2.61/UC OR 2.92), high perceived stress [2.29/2.67], alcohol use [0.40/0.43], and bronchial hyper-reactivity [3.04/2.36]. Four novel factors were associated with only CD: prenatal smoke exposure [1.89], having a bed partner [0.53], allergies [2.66], and cow's milk hypersensitivity [5.87]; and two solely with UC: carpet flooring [0.57] and neuroticism [1.32]. Nine factors were replicated.

CONCLUSIONS

In this study we identified 10 novel, and replicated nine previously reported, exposome factors associated with IBD. Identifying these factors is important for both understanding disease aetiology and future prevention strategies to decrease the development of IBD in genetically susceptible persons.

Onion bulb extract can both reverse and prevent colitis in mice via inhibition of pro-inflammatory signaling molecules and neutrophil activity

Background

Onion is one of the most commonly used plants in the traditional medicine for the treatment of various diseases. We recently demonstrated the anti-inflammatory properties of onion bulb extract (OBE) in reducing colitis severity in mice when administered at the same time of colitis induction. However, whether onion can reverse established colitis or even prevent its development has not been investigated.

Hypothesis

To test 1. whether OBE can reduce colitis severity when given either before (preventative approach) or after (treatment approach) colitis induction and if so, 2. what are the mechanisms by which onion can achieve these effects.

Methods

Colitis was induced by dextran sulfate sodium (DSS) administration using treatment and preventative approaches. The severity of the inflammation was determined by the gross and histological assessments. The colonic level/activity of pro-inflammatory molecules and immune cell markers was assessed by immunofluorescence and western blotting analysis. In vitro neutrophil superoxide release and survival was assessed by chemilumenecense and Annexin-V/7AAD assays respectively.

Results

OBE treatment significantly reduced colitis severity in both approaches, the colonic expression/activity profile of pro-inflammatory molecules, inhibited WKYMVm-induced superoxide release, and increased spontaneous apoptosis of neutrophils in vitro.

Conclusions

OBE can be used as an effective option in the prevention and/or the treatment of established colitis.

The Role of Epidemiological Evidence from Prospective Population Studies in Shaping Dietary Approaches to Therapy in Crohn's Disease

SCOPE

The concept that dietary factors are key risk and preventive agents in the development of Crohn's disease (CD), while widely believed and supported by epidemiological evidence, has yet to lead to clear identification of those factors through clinical trials. The aims are to examine the strength of the epidemiological evidence of diet and its association with CD, examine how interpretation of mostly epidemiological data has shaped ideas for potential dietary therapies, and to explore other factors that have driven the design of dietary clinical trials in CD.

METHODS

A literature search is performed in PubMed, Medline, EMBASE, and Google Scholar for prospective cohort studies and randomized clinical trials (RCTs) using search terms-"Crohn's disease," "diet," "risk," "remission," "treat," "cohort," "randomised."

RESULTS

Only four prospective cohort studies examine the relationship of diet and CD development, but these trials have been largely ignored by dietary RCTs in CD, which have used predominantly exclusion diets in small populations without objective endpoint assessment. Only one demonstrated clinical benefit to intestinal inflammation.

CONCLUSION

Investment in large multicenter dietary clinical trials that focus on dietary inclusions with objective endpoint assessment are needed to provide safe, sustainable dietary therapy to patients with CD.

Effect of Lifestyle Factors on Outcomes in Patients With Inflammatory Bowel Diseases

Various lifestyle factors including physical activity and obesity, stress, sleep, and smoking may modify the risk of developing inflammatory bowel diseases (IBDs). In patients with established IBD, these lifestyle factors may significantly impact the natural history and clinical outcomes. Recreational exercise decreases the risk of flare and fatigue in patients with IBD. In contrast, obesity increases the risk of relapse and is associated with higher anxiety, depression, fatigue, and pain and higher health care utilization. Obesity also modifies pharmacokinetics of biologic agents unfavorably and is associated with a higher risk of treatment failure. Sleep disturbance is highly prevalent in patients with IBD, independent of disease activity, and increases the risk of relapse and chronic fatigue. Similarly, stress, particularly perceived stress rather than major life events, may trigger symptomatic flare in patients with IBD, although its impact on inflammation is unclear. Cigarette smoking is associated with unfavorable outcomes including the risk of corticosteroid dependence, surgery, and disease progression in patients with Crohn's disease; in contrast, smoking does not significantly impact outcomes in patients with ulcerative colitis, although some studies suggest that it may be associated with a lower risk of flare. The effect of alcohol and cannabis use in patients with IBD is inconsistent, with some studies suggesting that cannabis may decrease chronic pain in patients with IBD, without a significant effect of biological remission. Although these lifestyle factors are potentially modifiable, only a few interventional studies have been conducted. Trials of structured exercise and psychological therapy including mindfulness-based therapies such as meditation and yoga and gut-directed hypnotherapy have not consistently demonstrated benefit in clinical and/or endoscopic disease activity in IBD, although may improve overall quality of life.

Dietary Guidance From the International Organization for the Study of Inflammatory Bowel Diseases

Recent evidence points to a plausible role of diet and the microbiome in the pathogenesis of both Crohn's disease (CD) and Ulcerative Colitis (UC). Dietary therapies based on exclusion of table foods and replacement with nutritional formulas and/or a combination of nutritional formulas and specific table foods may induce remission in CD. In UC, specific dietary components have also been associated with flare of disease. While evidence of varying quality has identified potential harmful or beneficial dietary components, physicians and patients at the present time do not have guidance as to which foods are safe, may be protective or deleterious for these diseases. The current document has been compiled by the nutrition cluster of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) based on the best current evidence to provide expert opinion regarding specific dietary components, food groups and food additives that may be prudent to increase or decrease in the diet of patients with inflammatory bowel diseases to control and prevent relapse of inflammatory bowel diseases.

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.

Clinical Significance of High-Mobility Group Box 1 Protein (HMGB1) and Nod-Like Receptor Protein 3 (NLRP3) in Patients with Ulcerative Colitis

Background

The aim of this study was to investigate the clinical significance of NLRP3 and HMGB1 in patients with active ulcerative colitis.

Material/Methods

This was a prospective observational study which included a total of 62 cases with active ulcerative colitis during January 2017 to December 2018. The patients were divided into a mild/moderate group or a severe group according to Sutherland Disease Activity Index (DAI) score. Clinical activity index and endoscopic index were used to determine the severity of UC. Serum levels of NLRP3, HMGB1, endothelin-1, IL-1β, and TNF-α were determined by enzyme-linked immunosorbent assay (ELISA).

Results

Sutherland DAI score, clinical activity index, and endoscopic index were all significantly higher in severe patients than in the mild/moderate group. NLRP3, HMGB1, endothelin-1, IL-1β, and TNF-α were significantly higher in severe UC patients. NLRP3 level was positively correlated with HMGB1, ET-1, IL-1β, and TNF-α levels. Both NLRP3 and HMGB1 were positively correlated with Sutherland DAI score, clinical activity index, and endoscopic index.

Conclusions

Both serum NLRP3 and HMGB1 were elevated in UC patients, and the serum levels of NLRP3 were positively correlated with serum levels of HMGB1, ET-1, IL-1β, and TNF-α, as well as severity of UC patients.

Dietary intake of total polyphenols and the risk of all-cause and specific-cause mortality in Japanese adults: the Takayama study

Purpose

Several epidemiological studies have demonstrated the health benefits of polyphenols, but the associations between polyphenol intake and mortality including total and major causes of death remain unclear. We investigated the associations between subjects’ total polyphenol intake and their mortality from all causes, cardiovascular disease (CVD), cancer, and other causes of death in a population-based cohort study in Japan.

Methods

A total of 29,079 residents of Takayama City, Japan were analyzed. Their dietary intake was assessed using a validated semi-quantitative food-frequency questionnaire (FFQ) in 1992. Mortality was ascertained over the subsequent 16 years. The dietary polyphenol intake was calculated by matching the subjects’ food consumption data with our original polyphenol content database.

Results

A total of 5339 deaths occurred during the follow-up. After multivariable adjustment, the highest quartile of total polyphenol intake compared with the lowest quartile was significantly associated with a lower risk of all-cause mortality (HR: 0.93, 95% CI: 0.82–0.99, p trend = 0.003). The subjects in the highest quartile showed significantly lower CVD mortality compared to those in the lowest quartile, and among the types of CVD mortality, a strong inverse association was observed for stroke mortality. Inverse associations were also observed for mortality from other causes, specifically digestive disease. The total polyphenol intake was not significantly associated with the risk of cancer mortality.

Conclusions

The results of this prospective study indicate that dietary total polyphenol intake in Japanese is inversely associated with all-cause mortality and mortality from cardiovascular and digestive diseases.

Environmental Risk Factors for Inflammatory Bowel Diseases: An Umbrella Review of Meta-analyses

BACKGROUND & AIMS

Multiple environmental factors have been associated with the development of inflammatory bowel diseases (IBDs). We performed an umbrella review of meta-analyses to summarize available epidemiologic evidence and assess its credibility.

METHODS

We systematically identified and appraised meta-analyses of observational studies examining environmental factors and risk of IBD (Crohn's disease [CD] or ulcerative colitis [UC]). For each meta-analysis, we considered the random effects estimate, its 95% confidence interval, the estimates of heterogeneity, and small-study effects, and we graded the evidence according to prespecified criteria. Methodologic quality was assessed with AMSTAR (ie, A Measurement Tool to Assess Systematic Reviews) 2.

RESULTS

We examined 183 estimates in 53 meta-analyses of 71 environmental factors related to lifestyles and hygiene, surgeries, drug exposures, diet, microorganisms, and vaccinations. We identified 9 factors that increase risk of IBD: smoking (CD), urban living (CD and IBD), appendectomy (CD), tonsillectomy (CD), antibiotic exposure (IBD), oral contraceptive use (IBD), consumption of soft drinks (UC), vitamin D deficiency (IBD), and non-Helicobacter pylori-like enterohepatic Helicobacter species (IBD). We identified 7 factors that reduce risk of IBD: physical activity (CD), breastfeeding (IBD), bed sharing (CD), tea consumption (UC), high levels of folate (IBD), high levels of vitamin D (CD), and H pylori infection (CD, UC, and IBD). Epidemiologic evidence for all of these associations was of high to moderate strength; we identified another 11 factors associated with increased risk and 16 factors associated with reduced risk with weak credibility. Methodologic quality varied considerably among meta-analyses. Several associations were based on findings from retrospective studies, so it is not possible to determine if these are effects of IBD or the results of recall bias.

CONCLUSIONS

In an umbrella review of meta-analyses, we found varying levels of evidence for associations of different environmental factors with risk of IBD. High-quality prospective studies with analyses of samples from patients with recent diagnoses of IBD are needed to determine whether these factors cause or are results of IBD and their pathogenic mechanisms.

Diet in the Pathogenesis and Management of Ulcerative Colitis; A Review of Randomized Controlled Dietary Interventions

Epidemiological and experimental studies have suggested that diet is one of the environmental factors that contributes to the onset and pathophysiology of ulcerative colitis. Although many patients suffering from ulcerative colitis attribute their symptoms or disease relapse to dietary factors, only a few well-designed randomized controlled trials have been done to investigate the role of diet in the management of ulcerative colitis. Here, we review the potential mechanisms of the relationship between diet and pathogenesis of ulcerative colitis and summarize randomized controlled dietary interventions that have been conducted in ulcerative colitis patients.

Dietary risk factors for inflammatory bowel diseases in a high-risk population: Results from the Faroese IBD study

Background

The Faroe Islands currently have the highest recorded inflammatory bowel disease (IBD) incidence in the world.

Objective

This study investigated environmental risk factors for IBD in the Faroese population.

Methods

Environmental exposure data including lifestyle risk factors and neurotoxicants collected for over 30 years were retrieved from the Children's Health and the Environment in the Faroes (CHEF) cohorts including mainly mother–child pairs, with exposure data collected from pregnant mothers. For lifestyle risk factors, the incidence of IBD and ulcerative colitis (UC) was calculated as the rate ratio (RR) with 95% confidence intervals (CI) in exposed versus non-exposed persons. For neurotoxicants RR was calculated for persons with high versus low exposure.

Results

Six cohorts included 5698 persons with complete follow-up data and at least one exposure, and 37 were diagnosed with IBD. For pilot whale/blubber, the RR was 1.02 (95% CI, 0.48–2.18); RR of 1.01 for fish (95% CI, 0.35–2.91); and of the pollutants studied, a statistical significantly increased risk was found for 1,1,1,-trichloro-2,2-bis-(p-chlorophenyl) ethane (p,p'-DDT); RR 3.04 (95% CI, 1.12–8.30). RRs were 1.96 (95% CI, 1.03–3.73) for smoking and 1.10 (95% CI, 0.55–2.19) for alcohol intake.

Conclusion

The high IBD incidence is unlikely to be caused by special dietary habits or by environmental pollutants.

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.

Factors associated with low adherence to oral 5-aminosalicylic acid in patients with ulcerative colitis

Background/Aims

It is well known that 5-aminosalicylic acid (5-ASA) is the standard first-line treatment for ulcerative colitis (UC). Medication adherence is an important factor in the treatment of UC. We aimed to identify predictors of low adherence to oral 5-ASA in Koreans with UC.

Methods

Between July 2017 and January 2018, we performed a multicenter, cross-sectional study across 6 University Hospitals in Korea. Medication adherence was assessed using the modified Morisky Medication Adherence Scale (MMAS-8) questionnaire. Our study included 264 patients with UC. Patients were requested to complete the self-reported MMAS-8 questionnaire and a survey assessing sociodemographic data. Adherence was categorized as low (scores<6), medium (scores 6–7), and high (score 8).

Results

The mean age of patients was 44±14 years, women comprised 43.6% of the study population and 49.8% of the studied population showed low adherence to oral 5-ASA. Age <40 years, alcohol consumption, and current smoking were significantly associated with low adherence to oral 5-ASA (age <40 years: odds ratio [OR] 1.76, 95% confidence interval [CI] 1.04–2.96, p = .034; alcohol consumption: OR 1.66, 95% CI 1.00–2.74, p = .049; current smoking: OR 4.06, 95% CI 1.08–15.18, p = .038). When data were classified based on gender, we observed that only in men, alcohol consumption and current smoking showed a significant association with low adherence to oral 5-ASA (alcohol consumption: OR 2.14, 95% CI 1.08–4.23, p = .029; current smoking: OR 5.07, 95% CI 1.32–19.41, p = .018). In women, only age <40 years was significantly associated with low adherence to oral 5-ASA (age <40 years: OR 3.71, 95% CI 1.59–8.66, p = .002).

Conclusion

Approximately 50% of patients with UC showed low adherence to oral 5-ASA. Predictors of low adherence were age <40 years, alcohol consumption, and current smoking habits. In men, alcohol consumption and current smoking were significant predictors of low adherence, whereas in women only age <40 years was significantly associated with low adherence.

The role of dietary factors in inflammatory bowel diseases: New perspectives

The current review aimed to elucidate the role of diet in every stage of inflammatory bowel diseases, from aspects of prevention, treatment and rehabilitation. Western diet, characterized by overconsumption of refined sugar and saturated fat and low consumption of dietary fiber, may partly be blamed for its pathogenesis. Some immune-modulated nutrients (fibers, monounsaturated fatty acids, n-3 polyunsaturated fatty acids and vitamin D) exert their potential beneficial effects on gut microbiota and immune function, resulting in clinical remission and/or preventing relapse. However, data is limited to conclude optimal micronutrient levels and therapeutic implications. Further, diet itself is complex; therefore, it is reasonable to evaluate diet as a whole rather than a single type of food. Some specific dietary patterns are generated for the management of inflammatory bowel diseases with controversial results. Only exclusive enteral nutrition has been widely recommended for pediatric patients with non-stricturing active Crohn's disease. Self-monitoring, avoidance of certain types of foods, limited intake of alcohol and smoking, supplementation of minerals and vitamins if deficiency is confirmed, and adherence to the diet enriched in vegetables and fruits and low in animal food and un-digested fiber during flares are the most common dietary recommendation. Further clinical trials with a high evidence rank are warranted.