Risk Of Inflammatory Bowel Disease Research Articles

The relationship between weight change and inflammatory bowel disease. A population-based cohort study, the HUNT study

Background The incidence of inflammatory bowel disease (IBD) is increasing. The prevalence of overweight and obesity is increasing in parallel with IBD and could contribute to IBD development. The aim of this study was to assess the relationship between weight change and the risk for IBD. Methods Data gathered from 55,896 adult participants in the three first population-based Trøndelag Health Studies (HUNT1-3), Norway, performed in 1984–2008 was used. The exposure was change in body mass index between two HUNT studies. The outcome was a new IBD diagnosis recorded during a ten-year follow-up period after the exposure assessment. The risk of IBD by weight change was assessed by Cox regression analyses reporting hazard ratios (HRs) and 95% confidence intervals (CIs), adjusted for sex, age, and smoking status. Results There were 334 new cases of ulcerative colitis (UC) and 54 of Crohn’s disease (CD). Weight loss decreased the risk of a new UC diagnosis by 38% (adjusted HR 0.62, 95% CI 0.39–0.97) and seemed to double the risk of getting a new CD diagnosis (adjusted HR 2.01, 95% CI 0.91–4.46). Weight gain was not associated with a new diagnosis of neither UC (adjusted HR 1.00, 95% CI 0.78–1.26) nor CD (adjusted HR 1.08, 95% CI 0.56–2.08). Conclusion In this study, weight loss was associated with decreased risk of UC. However, no associations were seen between weight gain and the risk of UC or CD, suggesting that the increasing weight in the general population cannot explain the increasing incidence of IBD.

Physical activity in the prevention and management of inflammatory bowel disease: a systematic review

Abstract Aim This study aimed to assess the potential role of physical activity (PA) in reducing the risk of developing inflammatory bowel diseases (IBDs) and in their management. Subject and methods A systematic review of literature was conducted up to October 2023 using the PubMed, Scopus, Web of Science and Cochrane Library databases. Observational studies, semi-experimental and experimental studies reporting PA effects were considered eligible. Data on disease status and PA characteristics, main outcomes and possible confounders were collected in a database. The Newcastle–Ottawa Quality Assessment Scale was used to assess risk of bias. Results Of the 29 articles included, six investigated PA and risk of IBDs and four of them showed an inverse relationship. Among the others, seven reported positive effects of PA on IBD symptoms, while all showed improvements in comorbidities, complications and quality of life. Conclusion PA seems to be effective in preventing or treating IBDs and their complications. Owing to the low quality of the majority of the studies and their heterogeneity, further research is needed to better understand which type and level of PA may be useful in the prevention and treatment of these diseases.

Causal association of blood cell traits with inflammatory bowel diseases: a Mendelian randomization study.

Observational studies have found associations between blood cell traits and inflammatory bowel diseases (IBDs), whereas the causality and dose-effect relationships are still undetermined. Two-sample Mendelian randomization (MR) analyses using linear regression approaches, as well as Bayesian model averaging (MR-BMA), were conducted to identify and prioritize the causal blood cell traits for Crohn's disease (CD) and ulcerative colitis (UC). An observational study was also performed using restricted cubic spline (RCS) to explore the relationship between important blood cell traits and IBDs. Our uvMR analysis using the random effects inverse variance weighted (IVW) method identified eosinophil (EOS) as a causal factor for UC (OR = 1.36; 95% CI: 1.13, 1.63). Our MR-BMA analysis further prioritized that high level of lymphocyte (LYM) decreased CD risk (MIP = 0.307; MACE = -0.059; PP = 0.189; = -0.173), whereas high level of EOS increased UC risk (MIP = 0.824; MACE = 0.198; PP = 0.627; = 0.239). Furthermore, the observational study clearly depicts the nonlinear relationship between important blood cell traits and the risk of IBDs. Using MR approaches, several blood cell traits were identified as risk factors of CD and UC, which could be used as potential targets for the management of IBDs. Stratified genome-wide association studies (GWASs) based on the concentration of traits would be helpful owing to the nonlinear relationships between blood cell traits and IBDs, as demonstrated in our clinical observational study. Together, these findings could shed light on the clinical strategies applied to the management of CD and UC.

Role of Vitamin D in the Pathogenesis of Inflammatory Bowel Diseases: Literature Review

The pathogenesis of inflammatory bowel diseases still remains unclear nowadays. Genetic disposition, impaired immune regulation, disturbance in intestinal microbiota composition, exposure to environmental factors are associated with the development of inflammation in intestinal mucosa and increased epithelial penetrance that define disease's development and progression. There is a theory in scientific literature that vitamin D deficiency (among other environmental factors) increases the risk of inflammatory bowel disease. However, the role of vitamin D in the development of gastrointestinal tract diseases remains poorly studied. This article presents current data on the vitamin D effect on the intestinal mucosa barrier function, on the immune system and on the intestinal microbiota in the context of inflammatory bowel diseases pathogenesis.

Serum Microcystin-LR Levels Linked with Risk of Inflammatory Bowel Disease: A Matched Case-Control Study in China

Serum Microcystin-LR Levels Linked with Risk of Inflammatory Bowel Disease: A Matched Case-Control Study in China

Breastfeeding duration is not associated with offspring inflammatory bowel disease risk in three population-based birth cohorts

Background and aimsBreastfeeding is critical for offspring health and development. While many observational studies report a protective effect between breastfeeding and inflammatory bowel disease (IBD), the relationship is not well-understood. MethodsWe used prospectively collected data from three population-based birth cohorts (Danish National Birth Cohort, Norwegian Mother, Father, and Child Cohort, and All Babies in Southeast Sweden) and cross-linked national registers to ascertain the impact of breastfeeding duration on offspring IBD risk in each country, using adjusted Cox proportional regression analyses. We performed meta-analyses to determine pooled estimates. ResultsWe included 148,737 offspring and 169,510 offspring in analyses of exclusive and any breastfeeding duration, respectively. During median follow-up of 16.3 to 22.3 years, between 1996 and 2021, 543 offspring were diagnosed with IBD. In each country, there was no association between exclusive breastfeeding duration and offspring IBD risk after adjusting for birth year (Denmark), offspring sex, parental IBD status, maternal education, smoking during pregnancy, age at delivery, mode of delivery, preterm birth, and small for gestational age. The pooled adjusted hazard ratio for IBD was 1.24 (95% CI 0.94, 1.62, Q =0.16, I2= 0.0%) and 1.02 (95% CI 0.85, 1.21, Q=1.45, I2= 0.0%) among offspring breastfed exclusively for ≥6 months and <4 months, respectively, compared to 4-5 months. Similarly, we found null associations in pooled analyses of any breastfeeding duration and IBD, subtypes Crohn’s disease and ulcerative colitis, as well as in cohort-specific analyses. ConclusionIn prospectively collected data from three population-based birth cohorts, the duration of exclusive or any breastfeeding was not associated with offspring IBD risk.

The IBD Risk gene, PTPN2, Is Required for Commensal-associated Th17 Responses to Protect Against Pathobiont Colonization

Background/Aim: Inflammatory bowel disease (IBD) involves multiple factors including genetic susceptibilities, intestinal permeability, microbiome dysbiosis, and expansion of intestinal pathobionts such as adherent-invasive E. coli (AIEC). Mice lacking the IBD risk gene, Ptpn2, exhibit expansion of murine adherent-invasive Escherichia coli ( mAIEC strain, UCR-PP2). Internal transcribed spacer analysis of luminal and mucosal-associated bacteria also indicated a decrease in the protective commensal bacteria, segmented filamentous bacteria (SFB). SFB adherence to intestinal epithelial cells (IEC) induces Th17 cell secretion of IL-17 and IL-22 to promote mucosal defense. The goal of this study was to determine if constitutive whole-body, or IEC-specific Ptpn2 loss in mice modulates SFB abundance, adherence, and downstream production of protective Th17 cytokine in mice. Methods: All mice were housed in specific pathogen free (SPF) vivarium. Distal ileum (2-3 cm) was collected from whole body Ptpn2-wild-type (WT), heterozygous (Het) and Ptpn2 constitutive knockout (KO) mice [Balb/c]; or tamoxifen (TMX)-induced IEC specific Ptpn2 knockout mice ( Ptpn2ΔIEC) and TMX-treated control littermates ( Ptpn2fl/fl) [C57Bl/6]. Tissues were fixed and observed using the Hitachi TM4000 Scanning Electron Microscope (SEM) to visualize SFB. qPCR was used to quantify relative abundance of SFB in the Ileum tissue obtained from Ptpn2ΔIEC and Ptpn2fl/fl mice. Confirmed SFB-free C57Bl/6 mice (10 weeks old; JAX labs; Stock# 000664) were infected for four consecutive days by 109 mAIEC bacteria in PBS. Cytokine protein levels were quantified by Luminex Multiplex Array of whole tissue lysates from cecum, proximal and distal colon regions from 18-21day old WT, HET or KO mice. Immune cells were isolated from the cecum, colon, lamina propria, the mesenteric lymph nodes and the spleen of WT, HET and KO mice and analyzed by flow cytometry for IL-22+, and IL-17+ T cells. Results: SFB adherence to IECs in Ptpn2 constitutive KO mice was visibly decreased by SEM compared to WT and Ptpn2 Het littermates. SEM showed a dramatic decrease in SFB abundance in Ptpn2ΔIEC mice compared to control littermates ( Ptpn2fl/fl). This was confirmed by PCR analysis showing a significant decrease in SFB in Ptpn2ΔIEC mice (p&lt;0.05; n=8). The absence of SFB permitted mAIEC to colonize and cause mild disease in SFB-free mice (JAX; p&lt;0.01; n=8). SFB loss in whole-body Ptpn2-KO mice correlated with a decrease in IL-17+ CD4+ cells in the colon compared to Ptpn2-Het (p&lt;0.001; n=7) and Ptpn2-WT littermates (p&lt;0.05; n=5). Ptpn2-KO mice exhibited higher IL-22 levels in the distal colon (p&lt;0.01; n=3), and increased IL-22+CD4+ T-cells in the cecum, mesenteric lymph nodes and spleen compared to Ptpn2-WT and Het littermates (p&lt;0.001). Conclusion: Loss of the IBD risk gene Ptpn2 in mice, either constitutively or in IECs, reduces the abundance of SFB a commensal inducer of Th17 responses. Consistent with reduced SFB, IL-17+CD4+ T cells were reduced in whole-body Ptpn2-KO mice indicating a loss of SFB-induced Th17 maturation. Despite reduced IL-17, we observed increased IL-22 expression in Ptpn2-KO mice suggesting that loss of PTPN2 provokes a compensatory SFB/IL-17-independent increase in IL-22 production. These findings identify how loss of PTPN2 activity disrupts homeostatic commensal-mucosal immune crosstalk to facilitate IBD-relevant pathobiont colonization. This study was supported by grants NIH-2R01-DK091281, 1R01AI153314-01, R21AI152017, 1R01DK130373, and R01AI165490 (D.F.M.) from the National Institutes of Health (NIH). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Factors that Increase the Risk of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic disorder of the gastrointestinal tract. It comprises Crohn’s disease (CD) and ulcerative colitis (UC) The disorder begins in young adulthood. It is characterised by remission and relapse. IBD significantly affects a person’s life more so, their productivity and ability to perform activities of daily living. Although IBD is prevalent in Western countries, the recent epidemiology data shows a rising global prevalence and incidence. Addressing IBD is important. Although it is not significantly associated with high morbidity rates, it is a significant burden to healthcare. Identifying the risk factors of IBD can help in improving preventative measures. Since IBD does not have a known cure, controlling for these factors can minimize the impact of the disease. Some of the risk factors that increase the risk of IBD are genetics, environmental factors such as smoking, diet, lifestyle changes, medications, and intestinal microbiome. Identifying the factors that contribute to the risk of developing IBD can help in creating effective measures that can prevent the pathogenesis of the disease.

Association between dietary inflammation index and inflammatory bowel disease in adults: Results from National Health and Nutrition Examination Survey 2009-2010.

Previous study has demonstrated that the Dietary Inflammation Index (DII) played a role in the risk of inflammatory bowel disease (IBD), however, the prevalence and risk factors for IBD are distinct across locations and groups, and therefore, the findings are debatable and warrant further investigation. A total of 4363 participants were calculated in the National Health and Nutrition Examination Survey (NHANES) 2009 to 2010, of whom 1.21% self-reported a history of IBD. DII values were performed as a good predictor of dietary inflammation based on data from two 24-h dietary reviews in the NHANES database. Comparing the multifarious effects along with variations of the whole population by grouping populations according to DII quartiles, dietary inflammation levels increased progressively from DII quartile 1(Q1) to quartile 4(Q4). The association between DII and IBD was tested with multi-variable logistic regression models, subgroup analyses and weighted generalized additive models. Participants in the Q4 group showed the highest levels of C-reactive protein and reduced haemoglobin and albumin levels. Logistic regression confirmed the odds ratios (95% confidence intervals) of IBD for DII were 0.99 (0.86, 1.15), 0.97 (0.84, 1.13) and 0.80 (0.66, 0.98) in models 1, 2 and 3, respectively. The negative correlation between DII and IBD among United States adults from the NHANES database became increasingly apparent as covariates were adjusted. Subgroup analyses and smoothed curve fitting confirmed the inverse results. The study revealed that DII was correlated with the overall physical well-being of participants. However, there was no significant association between DII and IBD.

Farming activities and risk of inflammatory bowel disease: a French nationwide population-based cohort study.

Epidemiological data regarding inflammatory bowel disease (IBD) are lacking, in particular for occupationally exposed populations. We investigated whether, among the entire French farm manager (FM) workforce, certain agricultural activities are more strongly associated with IBD than others. Nationwide population-based insurance claims and electronic health records from all FMs that worked at least once over the period 2002-2016 were used (n=1088561, 69% males). The outcome measure was the association between 26 farming activities and the risk of IBD, Crohn's disease (CD), and ulcerative colitis (UC), measured as hazard ratios (HRs), after adjusting for age, sex, pre-existing medical comorbidities, and farm location. The time to first chronic disease declaration was used as the underlying timescale. A model was generated for every activity and disease, utilizing a reference group comprising all FMs who abstained from the specified activity from 2002 to 2016. There were 1752 IBD cases, with 704 CD (40.2%) and 1048 UC (59.8%) cases, respectively. Elevated HRs were observed for fruit arboriculture (HR from 1.17 to 1.52) and dairy farming (HR from 1.22 to 1.46) for all IBD, in crop farming for CD only (HR=1.26 [95CI%: 1.06-1.49]), and in shellfish farming (HR from 2.12 to 2.51) for both CD and IBD. Further research regarding specific farming activities and exposures likely to modify the microbiota (e.g., pesticides, pathogens) is required to identify potential occupational risk factors (agricultural exposome) for IBD. Exposure to Mycobacterium avium subspecies paratuberculosis, cryptosporidium, environmental toxins, micro/nanoplastics, and pesticides represents promising research avenues.

Physical Activity Is Associated With A Decreased Risk Of Developing Inflammatory Bowel Disease: A Systematic Review And Meta-Analysis.

Modifiable risk factors in Inflammatory Bowel Disease (IBD), such as physical activity, may be utilised as prevention strategies. However, the findings of previous studies on the association between physical activity and IBD risk have been inconsistent. We aimed to perform a systematic review and meta-analysis to estimate the effect of physical activity on IBD risk. A search was conducted for relevant studies published before April 2023 that assessed the effect of pre-IBD diagnosis levels of physical activity on IBD incidence. Individual summary statistics (relative risks; RR), and confidence intervals (CI) were extracted with forest plots generated. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the quality of evidence. 10 observational studies were included. For cohort studies, there were 1,182 Crohn's disease (CD) and 2,361 ulcerative colitis (UC) patients, with 860,992 participants without IBD. For case-control studies, there were 781 CD to 2,636 controls, and 1,127 UC to 3,752 controls. Compared to individuals with low physical activity levels, the RRs of CD in individuals with high physical activity levels for cohort and case-control studies were 0.78 (95% CI 0.68-0.88, P = 0.0001) and 0.87 (95% CI 0.79-0.95, P = 0.003), respectively. For UC, the RRs were 0.62 (95% CI 0.43-0.88, P = 0.008) and 0.74 (95% CI 0.51-1.07, P = 0.11). This meta-analysis suggests that physical activity is inversely associated with the risk of developing IBD, more so in CD than in UC.

Higher incidence of paediatric inflammatory bowel disease by increasing latitude in Norway, but stable incidence by age.

To examine possible geographical and temporal differences in the incidence of childhood-onset inflammatory bowel disease (IBD) in Norway, motivated by previous research indicating relevant environmental factors explaining changing epidemiology. We analysed data from children born in Norway from 2004 to 2012 (n = 541 036) in a registry-based nationwide study. After validating registry diagnoses against medical records, we defined IBD as ≥2 entries of International Classification of Diseases, 10th revision (ICD-10) codes K50, K51 and K52.3 in the Norwegian Patient registry. We estimated hazard ratios (HR) for IBD across four geographical regions with a south-to-north gradient and the incidence by period of birth. By the end of follow-up on 31 December 2020, 799 IBD diagnoses were identified (Crohn's disease: n = 465; ulcerative colitis, n = 293, IBD: unclassified, n = 41). Compared to children in the southernmost region, there was almost a two-fold HR for IBD in children in the most Northern region (HR = 1.94, 95% Cl = 1.47-2.57; Mid region: HR = 1.68, 95% CI = 1.29-2.19, ptrend <0.001). These estimates remained largely unchanged after adjustment for potential confounding factors. The cohorts born in 2004-2006 and 2010-2012 had comparable cumulative incidences, with a slightly higher incidence for those born in 2007-2009. We observed an increase in the risk of IBD by increasing latitude which may suggest that environmental factors influence the development of IBD, although non-causal explanations cannot be ruled out.

Evaluating the causal association between bronchiectasis and different types of inflammatory bowel disease: a two-sample Mendelian randomization study.

Previous observational studies have established a connection between bronchiectasis and inflammatory bowel disease (IBD), but none of these studies have provided a clear explanation for the underlying cause of this relationship. The present study thus implemented Mendelian randomization (MR) design to explore possible bidirectional relationships between IBD and bronchiectasis risk, with an additional focus on Crohn's disease (CD) and ulcerative colitis (UC) as IBD subtypes. A large genome-wide association study (GWAS)-derived data pool was leveraged to examine the relationships between bronchiectasis and IBD, CD, and UC. Two-sample MR analyses were performed with an inverse variance weighted (IVW) approach supplemented with the MR-Egger and weighted median methods. Sensitivity analyses were used to further assess the reliability of the main MR study findings. The possibility of reverse causation was also evaluated using a reverse MR approach. The IVW MR analytical approach revealed that IBD (p = 0.074), UC (p = 0.094), and CD (p = 0.644) had no significant impact on the incidence of bronchiectasis, with the converse also being true (p = 0.471, p = 0.700, and p = 0.099, respectively). This MR analysis demonstrated that the higher occurrence of bronchiectasis in patients with IBD is not caused by genetic predisposition.

Increased Risk of Inflammatory Bowel Disease Among Patients With Nontyphoidal Salmonella Infections: A Population-Based Cohort Study.

Despite the known association between microorganisms and development of inflammatory bowel disease (IBD), the role of nontyphoidal Salmonella (NTS) in IBD is not adequately addressed. We aimed at elucidating the relationship between NTS infection and the risk of IBD. Based on the National Health Insurance Research Database in Taiwan, this retrospective cohort study enrolled patients with NTS infection (exposure group; n = 4651) and those without NTS infection (comparator group; n = 4651) who were propensity score matched (1:1) by demographic data, medications, comorbidities, and index date. All patients were followed until IBD onset, individual mortality, or December 31, 2018. Cox proportional hazards regression analysis was performed to determine the hazard ratios and 95% confidence intervals (CIs). Sensitivity analyses were used for cross-validation. The NTS group demonstrated an increased risk of IBD compared with the non-NTS groups (adjusted hazard ratio [aHR], 2.12; 95% CI, 1.62-2.78) with a higher risk of developing ulcerative colitis in the former (aHR, 2.27; 95% CI, 1.69-3.04). Nevertheless, the small sample size may contribute to lack of significant difference in Crohn's disease. Consistent findings were noted after excluding IBD diagnosed within 6 months of NTS infection (aHR, 2.28; 95% CI, 1.71-3.03), excluding those with enteritis/colitis before index date (aHR, 1.85; 95% CI, 1.28-2.68), excluding those using antibiotics for 1 month in the year before IBD onset (aHR, 1.81; 95% CI, 1.34-2.45), inverse probability of treatment weighting (aHR, 1.64; 95% CI, 1.31-2.04), and inclusion of individuals regardless of age (n = 10 431; aHR, 1.83; 95% CI, 1.53-2.19). Patients with NTS were associated with an increased risk of developing IBD, especially ulcerative colitis.

Shared genetic basis and causality between schizophrenia and inflammatory bowel disease: evidence from a comprehensive genetic analysis.

The comorbidity between schizophrenia (SCZ) and inflammatory bowel disease (IBD) observed in epidemiological studies is partially attributed to genetic overlap, but the magnitude of shared genetic components and the causality relationship between them remains unclear. By leveraging large-scale genome-wide association study (GWAS) summary statistics for SCZ, IBD, ulcerative colitis (UC), and Crohn's disease (CD), we conducted a comprehensive genetic pleiotropic analysis to uncover shared loci, genes, or biological processes between SCZ and each of IBD, UC, and CD, independently. Univariable and multivariable Mendelian randomization (MR) analyses were applied to assess the causality across these two disorders. SCZ genetically correlated with IBD (rg = 0.14, p = 3.65 × 10−9), UC (rg = 0.15, p = 4.88 × 10−8), and CD (rg = 0.12, p = 2.27 × 10−6), all surpassed the Bonferroni correction. Cross-trait meta-analysis identified 64, 52, and 66 significantly independent loci associated with SCZ and IBD, UC, and CD, respectively. Follow-up gene-based analysis found 11 novel pleiotropic genes (KAT5, RABEP1, ELP5, CSNK1G1, etc) in all joint phenotypes. Co-expression and pathway enrichment analysis illustrated those novel genes were mainly involved in core immune-related signal transduction and cerebral disorder-related pathways. In univariable MR, genetic predisposition to SCZ was associated with an increased risk of IBD (OR 1.11, 95% CI 1.07–1.15, p = 1.85 × 10−6). Multivariable MR indicated a causal effect of genetic liability to SCZ on IBD risk independent of Actinobacteria (OR 1.11, 95% CI 1.06–1.16, p = 1.34 × 10−6) or BMI (OR 1.11, 95% CI 1.04–1.18, p = 1.84 × 10−3). We confirmed a shared genetic basis, pleiotropic loci/genes, and causal relationship between SCZ and IBD, providing novel insights into the biological mechanism and therapeutic targets underlying these two disorders.

Mucosa-Associated Lymphoid Tissue Surgeries as a Possible Risk for Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis.

Inflammatory bowel disease (IBD) is a group of chronic inflammatory gastrointestinal disorders that are caused by genetic susceptibility and environmental factors and affects a significant portion of the global population. The gut-associated lymphoid tissue (GALT) is known to play a crucial role in immune modulation and maintaining gut microbiota balance. Dysbiosis in the latter has a known link to IBD. Therefore, the increasing prevalence of adenoidectomy in children should be explored for its potential association with IBD. The objective of this paper was to assess the association between adenoid tissue removal and the risk of developing Crohn's disease (CD) and ulcerative colitis (UC). We conducted a pooled meta-analysis to evaluate the extended clinical outcomes in patients who underwent appendicectomy and tonsillectomy compared to those who did not. Our approach involved systematically searching the PubMed database for relevant observational studies written in English. We followed the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines to collect data from various time periods, and to address the diversity in study results; we employed a random-effects analysis that considered heterogeneity. For outcomes, odds ratios (ORs) were pooled using a random-effects model. Seven studies, out of a total of 114,537, met our inclusion criteria. Our meta-analysis revealed a significant association between appendicectomy and CD (OR: 1.57; 95% confidence interval (CI): 1.01 - 2.43; heterogeneity I2 = 93%). Similarly, we found a significant association between tonsillectomy and CD (OR: 1.93; 95% CI: 0.96 - 3.89; I2 = 62%). However, no significant association was observed between appendicectomy and UC (OR: 0.60; 95% CI: 0.24 - 1.47; I2 = 96%), while a modest association was found between tonsillectomy and UC (OR: 1.24; 95% CI: 1.18 - 1.30; I2 = 0%). In summary, we found that the trend of appendicectomy is linked to higher odds of CD, and tonsillectomy is more likely associated with increased odds for both CD and UC, with a risk of bias present.

Type II diabetes mellitus increases the risk of inflammatory bowel disease in a prospective cohort study

Inflammatory bowel disease is a common digestive disorder and diabetes can lead to intestinal dysfunction. Patients with inflammatory bowel disease in combination with diabetes present a higher rate of hospitalization and consumption of medical resources, yet the association between type 2 diabetes and Inflammatory bowel disease remains unknown. We studied 313,008 participants from the UK Biobank, including 5891 patients with type 2 diabetes at baseline. Multivariate Cox proportional risk models were constructed to examine the risks associated with type 2 diabetes and inflammatory bowel disease and its subtypes (Crohn's disease, ulcerative colitis). Potential confounders including sociodemographic, lifestyle, physical body indicators, psychological state, hypertension, and thyroid-related disorders were adjusted. Propensity score matching was also performed to analyze their sensitivity. Of a total of 313,008 participants included in the study, 5891 (1.88 %) were diagnosed with type 2 diabetes mellitus at baseline and 1829 (0.58 %) of the entire cohort developed inflammatory bowel disease during follow-up, with a median follow-up time of 13.72 years. Patients with type 2 diabetes had a higher cumulative risk of inflammatory bowel disease compared to the non-type 2 diabetes population (inflammatory bowel disease: 1.24% vs. 0.57%, p<0.001; Crohn's disease: 0.46% vs. 0.15%, p<0.001; ulcerative colitis: 0.73% vs. 0.35%, p<0.001). Multivariate Cox regression analysis showed that type 2 diabetes was independently associated with inflammatory bowel disease (Hazard Ratio: 1.61 [95% Confidence Interval: 1.26-2.06], p<0.001), Crohn's disease (Hazard Ratio: 2.10 [95% Confidence Interval: 1.39-3.17], p<0.001) and ulcerative colitis (Hazard Ratio: 1.58 [95% Confidence Interval: 1.15-2.18], p=0.005). In a propensity-matched analysis, type 2 diabetes still showed its ability to predict the risk of inflammatory bowel disease (Hazard Ratio: 2.09 [95% Confidence Interval: 1.55-2.83], p<0.001), Crohn's disease (Hazard Ratio: 3.49 [95% Confidence Interval: 2.00 to 6.09], p<0.001), and ulcerative colitis (Hazard Ratio: 1.76 [95% Confidence Interval: 1.20 to 2.56], p=0.003) of robustness. In patients with type 2 diabetes mellitus, the risk of inflammatory bowel disease is higher, and the presence of gastrointestinal symptoms in patients with type 2 diabetes requires vigilance for the possibility of inflammatory bowel disease in clinical practice.

Circulating 25-hydroxyvitamin D concentration can predict bowel resection risk among individuals with inflammatory bowel disease in a longitudinal cohort with 13 years of follow-up.

Although the beneficial properties of vitamin D in anti-inflammation and immunity-modulation are promising in the management of inflammatory bowel disease (IBD), data were limited for the critical IBD prognosis. The association between serum vitamin D levels and the risk of bowel resection in individuals with IBD remains largely unknown. We performed a longitudinal cohort study among 5474 individuals with IBD in the UK Biobank. Serum 25-hydroxyvitamin D [25(OH)D] was measured using direct competitive chemiluminescent immunoassay. Bowel resection events were ascertained via national inpatient data. Multivariable-adjusted Cox proportional hazard regression was used to examine the association between serum 25(OH)D and bowel resection risk, presented with hazard ratios (HRs) and 95% confidence intervals (CIs). Restricted cubic spline (RCS) was used to evaluate dose-response associations. During a mean follow-up of 13.1 years, we documented 513 incident bowel resection cases. Compared to participants with vitamin D deficiency, non-deficient participants showed a significantly reduced bowel resection risk in IBD (HR 0.72, 95% CI 0.59-0.87, P=0.001), Crohn's disease (CD, HR 0.74, 95% CI 0.56-0.98, P=0.038), and ulcerative colitis (UC, HR 0.73, 95% CI 0.57-0.95, P=0.020). When comparing extreme quintiles of 25(OH)D level, participants with IBD showed a 34% reduced risk of bowel resection (95% CI 11%-51%, P=0.007) and participants with UC showed a 46% reduced risk (95% CI 19%-64%, P=0.003), while this association was not significant in CD (HR 0.93, 95% CI 0.59-1.45, P=0.740). Linear dose-response associations were observed using the RCS curve (all P-nonlinearity>0.05). Increased serum level of 25(OH)D is independently associated with reduced bowel resection risk in IBD. This association was significant in UC but may not be stable in CD. Vitamin D deficiency is a risk factor for bowel resection in individuals with IBD, and may be an effective metric in predicting and risk-screening surgical events.

Association between inflammatory bowel disease and cancer risk: evidence triangulation from genetic correlation, Mendelian randomization, and colocalization analyses across East Asian and European populations

BackgroundInflammatory bowel disease (IBD), which includes Crohn’s disease (CD) and ulcerative colitis (UC), has been associated with several cancer risks in observational studies, but the observed associations have been inconsistent and may face the bias of confounding and reverse causality. The potential causal relationships between IBD and the risk of cancers remain largely unclear.MethodsWe performed genome-wide linkage disequilibrium score regression (LDSC), standard two-sample Mendelian randomization (MR), and colocalization analyses using summary genome-wide association study (GWAS) data across East Asian and European populations to evaluate the causal relationships between IBD and cancers. Sensitivity analyses for the MR approach were additionally performed to explore the stability of the results.ResultsThere were no significant genetic correlations between IBD, CD, or UC and cancers (all P values > 0.05) in East Asian or European populations. According to the main MR analysis, no significant causal relationship was observed between IBD and cancers in the East Asian population. There were significant associations between CD and ovarian cancer (odds ratio [OR] = 0.898, 95% CI = 0.844–0.955) and between UC and nonmelanoma skin cancer (OR = 1.002, 95% CI = 1.000–1.004, P = 0.019) in the European population. The multivariable MR analysis did not find any of the above significant associations. There was no shared causal variant to prove the associations of IBD, CD, or UC with cancers in East Asian or European populations using colocalization analysis.ConclusionsWe did not provide robust genetic evidence of causal associations between IBD and cancer risk. Exposure to IBD might not independently contribute to the risk of cancers, and the increased risk of cancers observed in observational studies might be attributed to factors accompanying the diagnosis of IBD.

Atopic Dermatitis in Early Childhood and Risk of Inflammatory Bowel Disease: A Scandinavian Birth Cohort Study

ObjectiveTo examine the association between early-life atopic manifestations and later risk of inflammatory bowel disease (IBD), for which prospective data are scarce. Study designThe population-based All Babies in Southeast Sweden (ABIS) and Norwegian Mother, Father, and Child (MoBa) cohorts follow children from birth (ABIS 1997–1999; MoBa 2000–2009) to the end of 2021. Based on validated questionnaires, parents prospectively reported information on asthma, food-related allergic symptoms, atopic dermatitis, and allergic rhinitis by age 3. IBD was defined by ≥2 diagnostic records in the national health registries. Cox regression estimated hazard ratios adjusted (aHR) for parental IBD, atopy, education level, smoking habits, and national origin. Cohort-specific estimates were pooled using a random-effects model. ResultsWe compiled data on 83,311 children (ABIS, n=9,041; MoBa, n=74,270). In over 1,174,756 person-years of follow-up, 301 participants were diagnosed with IBD. Children with atopic dermatitis at age 3 had an increased risk of IBD (pooled aHR=1.46 [95% confidence interval [CI]=1.13-1.88]), Crohn’s disease (pooled aHR=1.53 [95%CI=1.04-2.26]), and ulcerative colitis (pooled aHR=1.78 [95%CI=1.15-2.75]). Conversely, any atopic manifestation by age 3 was not associated with IBD (pooled aHR=1.20 [95%CI=0.95-1.52]), nor were analyses specifically focused on early-life food-related allergic symptoms, asthma, and allergic rhinitis. ConclusionWhile atopic manifestations in early childhood were overall not associated with IBD, children with atopic dermatitis specifically were at increased risk of developing IBD, suggesting shared etiological traits; these findings might be useful in identifying at-risk individuals for IBD.