Long-term Risk of Stroke in Patients With Inflammatory Bowel Disease: A Population-Based, Sibling-Controlled Cohort Study, 1969-2019

Network analysis of extraintestinal manifestations and associated autoimmune disorders in Crohn's disease and ulcerative colitis

We detect and interactively visualize occurrence, frequency, sequence, and clustering of extraintestinal manifestations (EIM) and associated immune disorders (AID) in 30,334 inflammatory bowel disease (IBD) patients (Crohn's disease (CD) n = 15924, ulcerative colitis (UC) n = 11718, IBD unclassified, IBD-U n = 2692, 52% female, median age 40 years (IQR: 25)) with artificial intelligence (AI). 57% (CD > UC 60% vs. 54%, p < 0.00001) had one or more EIM and/or AID. Mental, musculoskeletal and genitourinary disorders were most frequently associated with IBD: 18% (CD vs. UC 19% vs. 16%, p < 0.00001), 17% (CD vs. UC 20% vs. 15%, p < 0.00001) and 11% (CD vs. UC 13% vs. 9%, p < 0.00001), respectively. AI detected 4 vs. 5 vs. 5 distinct EIM/AID communities with 420 vs. 396 vs. 467 nodes and 11,492 vs. 9116 vs. 16,807 edges (links) in CD vs. UC vs. IBD, respectively. Our newly developed interactive free web app shows previously unknown communities, relationships, and temporal patterns-the diseasome and interactome.

The gut-organ axis: Clinical aspects and immune mechanisms

The gut-brain axis exemplifies the bidirectional connection between the intestines and the brain, as evidenced by the impact of severe stress on gastrointestinal symptoms including abdominal pain and diarrhea, and conversely, the influence of abdominal discomfort on mood. Clinical observations support the notion of the gut-brain connection, including an increased prevalence of inflammatory bowel disease (IBD) in patients with depression and anxiety, as well as the association of changes in the gut microbiota with neurological disorders such as multiple sclerosis, Parkinson's disease, stroke and Alzheimer's disease. The gut and brain communicate via complex mechanisms involving inflammatory cytokines, immune cells, autonomic nerves, and gut microbiota, which contribute to the pathogenesis in certain gut and brain diseases. Two primary pathways mediate the bidirectional information exchange between the intestinal tract and the brain: signal transduction through bloodstream factors, such as bacterial metabolites and inflammatory cytokines, and neural pathways, such as neurotransmitters and inflammatory cytokines within the autonomic nervous system through the interaction between the nerve cells and beyond. In recent years, the basic mechanisms of the pathophysiology of the gut-brain axis have been gradually elucidated. Beyond the gut-brain interaction, emerging evidence suggests the influence of the gut extends to other organs, such as the liver and lungs, through intricate inter-organ communication pathways. An increasing number of reports on this clinical and basic cross-organ interactions underscore the potential for better understanding and novel therapeutic strategies targeting inter-organs networks. Further clarification of interactions between multiorgans premises transformative insights into cross-organ therapeutic strategies.

Risk of stroke in patients with inflammatory bowel disease: a systematic review and meta-analysis

BACKGROUND

Current studies suggest a potential link between inflammatory bowel disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), and cardiovascular diseases, such as stroke. This study aimed to assess the risk of stroke in IBD patients compared to general population.

METHODS

Systematic search was done in PubMed, Embase, CENTRAL, Scopus, and CINAHL databases for studies published till September 2023. Using a random-effects model, the hazard ratios (HRs) with 95% confidence intervals (CIs) for stroke occurrence were calculated. Subgroup analyses were done to estimate pooled HR with 95%CI for CD, UC, and overall IBD cases separately. Publication bias assessment was done by Begg's and Egger's tests.

RESULTS

Thirteen studies with 2,802,955 participants were included. IBD patients in general had significantly higher risk of stroke, with HR of 1.30 [95% CI 1.21-1.39]. Subgroup analysis demonstrated an HR of 1.35 [95% CI 1.22-1.49] for CD and 1.15 [95% CI 1.09-1.22] for UC. Substantial heterogeneity was detected across studies, with no substantial publication bias. Sensitivity analyses affirmed the stability of findings.

CONCLUSION

IBD in general, and Crohn's disease in particular are associated with significantly higher risk of stroke. Our findings further emphasize the importance of cardiovascular risk assessment and management strategies in IBD care.

PROTOCOL REGISTRATION

PROSPERO, CRD42023470602.

Inflammatory Bowel Disease and Stroke: Exploring Hidden Vascular Risks

Inflammatory bowel disease (IBD), encompassing Crohn's disease and ulcerative colitis, is primarily known for its gastrointestinal manifestations. However, emerging evidence suggests a potential link between IBD and an increased risk of stroke, likely mediated by chronic systemic inflammation, endothelial dysfunction, and a prothrombotic state. Despite this growing recognition, the exact mechanisms and extent of this association remain unclear, highlighting a critical knowledge gap. This review aims to systematically analyze the association between IBD and stroke, exploring the underlying vascular mechanisms and identifying potential risk factors contributing to cerebrovascular events in IBD patients. A comprehensive literature search was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines across PubMed, Scopus, and Google Scholar using keywords such as "IBD," "Stroke," "Chronic inflammation," "Cerebrovascular risk," and "Gut-brain axis." After screening 150 studies and applying inclusion and exclusion criteria, six studies were included in the final synthesis. The findings suggest that chronic inflammation in IBD plays a key role in increasing stroke risk through endothelial dysfunction and a heightened prothrombotic state, with additional risk factors such as atrial fibrillation during active IBD flares further contributing to cerebrovascular events. While biologic therapies, including tumor necrosis factor (TNF)-alpha inhibitors, are effective in reducing systemic inflammation, their impact on mitigating stroke risk remains inconclusive. Given the potential role of IBD as an independent risk factor for stroke, a multidisciplinary approach to management is crucial. Addressing modifiable risk factors through pharmacologic interventions such as biologics, statins, and antiplatelet agents, alongside lifestyle modifications, could help reduce cerebrovascular complications in IBD patients. Further research is needed to explore personalized therapeutic strategies and establish clearer preventive guidelines for this at-risk population.

Exploring the causal inference of inflammatory bowel disease and ischemic stroke: a bidirectional two-sample Mendelian randomization study

Growing evidence suggests inflammatory bowel disease (IBD) is linked to ischemic stroke (IS); however, the results are inconclusive. Therefore, it remains uncertain whether the association between IBD and IS is causal. Herein, we performed a bidirectional Mendelian randomization (MR) study to examine the causal association of IBD with IS. We obtained summary-level data for IBD and IS from several publicly released genome-wide association studies to conduct a two-sample bidirectional Mendelian randomization (MR) analysis. Herein, the inverse-variance weighted method was utilized as the primary approach. Then, we applied the weighted median and MR-Egger estimators for the follow-up sensitivity analyses. In addition, the MR-Egger intercept test was performed to detect the potential directional pleiotropy. Genetically predicted IBD was not causally associated with IS and IS subtypes (IS: OR = 0.99, 95% CI 0.98-1.01, p = 0.49; large artery atherosclerosis stroke: OR = 1.00, 95% CI: 0.96-1.05, p = 0.88; cardioembolic stroke: OR = 0.99, 95% CI 0.96-1.03, p = 0.75; small-vessel occlusion stroke: OR = 1.02, 95% CI 0.99-1.05, p = 0.16). Moreover, we did not find a significant causal effect of UC or CD on IS and IS subtypes. Furthermore, there was no significant association observed between IS and IBD in the reverse MR analysis. The estimates were consistent across sensitivity analyses. Our MR analysis does not support a bidirectional causal association between IBD and IS, despite observational studies reporting an association of IBD with IS.

Incidence and risk factors for thromboembolic events in pediatric-onset inflammatory bowel disease: A French population-based study

INTRODUCTION

Patients with inflammatory bowel disease (IBD) are at higher risk of thromboembolic events (TE). In pediatric-onset IBD, more data on incidence and risk factors of venous (VTE) and arterial events (ATE) at the population level are needed to guide thromboprophylaxis.

METHODS

All patients aged ≤ 16 years diagnosed with Crohn's disease (CD) or ulcerative colitis (UC) between 1988 and 2011 in the prospective EPIMAD population-based registry were followed until 2013. Every TE occurring during the follow-up period was included.

RESULTS

A total of 1,344 patients were included: 1,007 with CD and 337 with UC, and a median diagnosis age of 14.3 years. After a median follow-up of 8.3 years, 2 (0.15 %) ATE and 15 (1.1 %) VTE occurred at median age of 20.4 years. The global incidence rate of thromboembolic events was 1.32 per 1000 person-years. Periods of active disease (HR=8.4, p = 0.0002), the 3-month-period following surgery (HR=16.4, p = 0.0002) and hospitalization (HR=21.7, p < 0.0001) were found to be associated with an increased risk of VTE. A lower rate of VTE was found in patients treated with 5-aminosalicylates (HR=0.1, p = 0.002).

CONCLUSION

The risk of TE was low in this population. VTE were strongly associated with active disease, surgery and hospitalization.

Risk of Intestinal Complications, Extraintestinal Morbidity, and Mortality in Patients with Crohn's Disease and Ocular Involvement

PURPOSE

Patients with Crohn's disease (CD) and subsequent ocular manifestations may have worse outcomes when compared to matched patients with CD without ocular disease.

METHODS

In this retrospective cohort study, an aggregated electronic health records research network, TriNetX (Cambridge, MA, USA), was used to identify patients diagnosed with CD stratified by the presence or absence of ocular involvement with at least 1 year of follow-up. Propensity score matching (PSM) was performed to control for baseline demographics and medical comorbidities.

RESULTS

Patients with CD with ocular disease showed a greater risk of undergoing bowel resections (RR: 2.06, 95% CI: 1.48-2.85, p < 0.001), developing other CD-related gastrointestinal complications (RR: 1.31, CI: 1.15-1.49, p < 0.001), or acquiring Clostridioides difficile infections (RR: 2.19, CI: 1.89-2.54, p < 0.001). Further, patients with CD with ocular sequelae had a greater risk of developing NASH (RR: 1.43, CI: 1.31-1.56, p < 0.001), CD-related nutrient deficiencies (RR: 1.38, CI: 1.29-1.49, p < 0.001), iron deficiency anemia (RR: 1.41, CI: 1.33-1.50, p < 0.001), CD-related dermatological disease (RR: 1.84, CI: 1.65-2.05, p < 0.001), osteoporosis (RR: 1.49, CI: 1.37-1.64, p < 0.001) and primary sclerosing cholangitis (RR: 1.63, CI: 1.11-2.38, p = 0.011). Among patients with CD with ocular involvement, there was an elevated risk of MI (RR: 1.36, CI: 1.14-1.63, p < 0.001), stroke (RR: 1.42, CI: 1.18-1.70, p < 0.001), VTE (RR: 1.37, CI: 1.22-1.54, p < 0.001), and sepsis (RR: 1.53, CI: 1.37-1.71, p < 0.001).

CONCLUSIONS

Patients who have CD and subsequent ocular involvement have an increased risk of local intestinal complications, extraintestinal morbidity, and cardiovascular complications when compared to patients with CD without ocular involvement.

Risk of Common Neurological Disorders in Adult Patients with Inflammatory Bowel Disease: A Systematic Review and Meta-analysis

BACKGROUND

Several studies investigated the risks of neurological conditions in patients with inflammatory bowel disease (IBD), with some variability in findings. We aimed to perform a systematic review and meta-analysis of available evidence to elucidate the association between IBD and the risks of common neurological disorders.

METHODS

We conducted a literature search through Embase, PubMed, Scopus, and ProQuest databases from inception to June 30, 2023, to identify cohort studies assessing the risk of developing stroke, all-cause dementia, Parkinson's disease (PD), multiple sclerosis (MS), seizure/epilepsy, and peripheral neuropathy in adult IBD patients compared with non-IBD population. We combined hazard ratios (HRs) with 95% confidence intervals (CIs) to compute pooled estimates using a random-effects model.

RESULTS

In total, 22 cohort studies were included, of which 9 studies reported 7074 stroke events in 202 460 IBD patients, 5 studies reported 3783 all-cause dementia diagnoses in 109 602 IBD patients, 7 studies reported 932 PD diagnoses in 354 792 IBD patients, and 1 study reported 6 MS events in 35 581 IBD patients. We observed increased risks of incident stroke (pooled HR = 1.19; 95% CI, 1.06-1.31), all-cause dementia (pooled HR = 1.22; 95% CI, 1.05-1.38), PD (pooled HR = 1.39; 95% CI, 1.20-1.58), and MS (HR = 2.89; 95% CI, 1.02-8.42). No eligible studies were found on peripheral neuropathy and seizure/epilepsy.

CONCLUSIONS

Inflammatory bowel disease may be modestly associated with increased risks of stroke, all-cause dementia, and PD. Further longitudinal studies are warranted to investigate potential links with MS, seizure/epilepsy, and peripheral neuropathy, as well as their clinical significance.

Dietary Determinants of Metabolic and Gut Microbial Health in Patients with Inflammatory Bowel Disease

Background: Diet has been linked to gut dysbiosis and the onset, course, and response to treatment of patients with IBD and metabolic disease. Methods: This single-centre prospective case-control study investigated the relationship between dietary intake, metabolic profile, and stool microbial composition in 57 individuals with IBD in clinical remission and 24 healthy individuals (HC). Participants' baseline anthropometric measurements, serum metabolic parameters, lipid profiles, and oral and stool samples for microbiota testing were collected. Their dietary intake and physical activity were documented. A partially corrected correlation was performed to examine the associations between variables and p-values adjusted for multiple comparisons using the Benjamini-Hochberg equation (adj-p). Results: In participants with IBD, the intake of saturated fat correlated positively, and the intake of dietary fibre correlated negatively with anthropometric indices (saturated fat and BMI: r = 0.37, adj-p = 0.04, fibre and BMI: r = -0.45, adj-p = 0.01). Higher anthropometric indices were associated with poorer glucose control and a less favourable serum lipid profile (BMI and insulin: r = 0.48, p < 0.01, WHR and triglycerides: r = 0.57, p < 0.01). The stool microbiota of participants in the IBD group was less diverse and more similar to their oral microbiota than was observed in the HC group (Mann-Whitney U test p = 0.03). Within the IBD group, a higher intake of added sugar and processed meat and a higher serum insulin level was associated with lower stool microbial alpha diversity (processed meat intake and Shannon's diversity: r = -0.43, adj-p = 0.02; added sugar and Shannon's diversity: r = -0.39, adj-p = 0.03; insulin and Shannon's diversity: r = -0.45, adj-p = 0.02). Neither the dietary intake nor stool microbial composition correlated with the risk of disease flaring. Conclusions: Our findings suggest that dietary intake is associated with the metabolic health and gut microbial composition of IBD patients.

Risk of heart failure in inflammatory bowel disease: a Swedish population-based study

BACKGROUND AND AIMS

Dysregulation of inflammatory and immune responses has been implicated in the pathogenesis of heart failure (HF). But even if inflammation is a prerequisite for inflammatory bowel disease (IBD), little is known about HF risk in IBD.

METHODS

In this Swedish nationwide cohort, patients with biopsy-confirmed IBD were identified between 1969 and 2017 [n = 81 749, Crohn's disease (CD, n = 24 303), ulcerative colitis (UC, n = 45 709), and IBD-unclassified (IBD-U, n = 11 737)]. Each patient was matched with up to five general population reference individuals (n = 382 190) and IBD-free full siblings (n = 95 239) and followed until 31 December 2019. Flexible parametric survival models estimated the adjusted hazard ratio (aHR) and standardized cumulative incidence for HF, with 95% confidence intervals (CI).

RESULTS

There were 5582 incident HF identified in IBD patients (incidence rate [IR]: 50.3/10 000 person-years) and 20 343 in reference individuals (IR: 37.9) during a median follow-up of 12.4 years. IBD patients had a higher risk of HF than reference individuals (aHR 1.19, 95% CI 1.15-1.23). This increased risk remained significant ≥20 years after IBD diagnosis, leading to one extra HF case per 130 IBD patients until then. The increased risk was also observed across IBD subtypes: CD (IR: 46.9 vs. 34.4; aHR 1.28 [1.20-1.36]), UC (IR: 50.1 vs. 39.7; aHR 1.14 [1.09-1.19]), and IBD-U (IR: 60.9 vs. 39.0; aHR 1.28 [1.16-1.42]). Sibling-controlled analyses showed slightly attenuated association (IBD: aHR 1.10 [1.03-1.19]).

CONCLUSIONS

Patients with IBD had a moderately higher risk of developing HF for ≥20 years after IBD diagnosis than the general population.

Cardiovascular risk assessment in inflammatory bowel disease with metabolic dysfunction-associated steatotic liver disease

BACKGROUND AND AIMS

Inflammatory bowel disease (IBD) has been reported to increase the risk of early atherosclerosis even in young patients. Moreover, metabolic dysfunction-associated steatotic liver disease (MASLD), which has been linked to IBD, is a well-recognized but underdiagnosis entity related to cardiovascular risk. We analyze the impact of MASLD in IBD patients' cardiovascular risk through both advanced lipoprotein profile sorted by nuclear magnetic resonance spectroscopy, and carotid artery intima-media thickness (CIMT).

METHODS

Cross-sectional cohort study which involves 941 IBD adult outpatients. Of them, 50 patients with IBD who met criteria for MASLD and 50 with IBD without MASLD, matched by sex and age were included. Alterations in CIMT were evaluated considering abnormal measures above the 75th percentile adjusted for sex and age. Specific advanced lipoprotein profile was also carried out.

RESULTS

Most of the patients had an abnormal CIMT (58%). MASLD (OR=5.05, CI 95%=1.71-14.92) and female sex (OR=3.32, CI 95%=1.03-10) were significantly associated with CIMT alterations. Dense LDL particles (with high cholesterol composition in general cohort (OR=3.62, 95% CI=1.07-12.19) and high triglycerides density in young subgroup (OR=6.25, 95% CI=1.04-50) but not total LDL cholesterol were associated with CIMT alterations.

CONCLUSIONS

MASLD and female sex are associated with early atherosclerosis in IBD patients. Dense LDL particle in combination with vascular imaging findings should be evaluated as non-invasive tools in the management of cardiovascular risk in IBD patients.

A leaky gut dysregulates gene networks in the brain associated with immune activation, oxidative stress, and myelination in a mouse model of colitis

The gut and brain are increasingly linked in human disease, with neuropsychiatric conditions classically attributed to the brain showing an involvement of the intestine and inflammatory bowel diseases (IBDs) displaying an ever-expanding list of neurological comorbidities. To identify molecular systems that underpin this gut-brain connection and thus discover therapeutic targets, experimental models of gut dysfunction must be evaluated for brain effects. In the present study, we examine disturbances along the gut-brain axis in a widely used murine model of colitis, the dextran sodium sulfate (DSS) model, using high-throughput transcriptomics and an unbiased network analysis strategy coupled with standard biochemical outcome measures to achieve a comprehensive approach to identify key disease processes in both colon and brain. We examine the reproducibility of colitis induction with this model and its resulting genetic programs during different phases of disease, finding that DSS-induced colitis is largely reproducible with a few site-specific molecular features. We focus on the circulating immune system as the intermediary between the gut and brain, which exhibits an activation of pro-inflammatory innate immunity during colitis. Our unbiased transcriptomics analysis provides supporting evidence for immune activation in the brain during colitis, suggests that myelination may be a process vulnerable to increased intestinal permeability, and identifies a possible role for oxidative stress and brain oxygenation. Overall, we provide a comprehensive evaluation of multiple systems in a prevalent experimental model of intestinal permeability, which will inform future studies using this model and others, assist in the identification of druggable targets in the gut-brain axis, and contribute to our understanding of the concomitance of intestinal and neuropsychiatric dysfunction.

Association between inflammatory bowel disease and risk of stroke: a systematic review and meta-analysis of cohort studies

Background/objectives

Recently, four meta-analyses have explored the association between inflammatory bowel disease (IBD) and the risk of stroke. These studies have demonstrated that people with IBD may be at an increased risk of stroke. However, some limitations such as high heterogeneity and the lack of uniformity in the types of research, especially the reuse of some sample sizes, cannot be neglected. These factors reduce the credibility of their research conclusions. Therefore, we conducted a meta-analysis to explore this possible association.

Methods

PubMed, Embase, and Web of Science were searched from inception to 30 June 2023. A random effects model with the generic inverse variance method was used in this meta-analysis. The Review Manager software was used to obtain all relative risks (RRs) and their 95% confidence intervals (CIs). Publication bias was tested, and sensitivity and subgroup analyses were conducted to explore possible heterogeneities.

Results

This meta-analysis included 12 cohort studies (involving 4,495,055 individuals). Meta-analysis of these data has shown that IBD was associated with an increased risk of stroke (RR = 1.19, 95%CI:1.14-1.24, p < 0.00001). Our results were stable and robust in subgroup and sensitivity analyses.

Conclusions

Our results suggest that IBD is associated with an increased risk of stroke. To reduce the incidence of stroke, patients with IBD are encouraged to undergo stroke risk assessments, especially for young female patients; assessing the risk of ischemic stroke is of particular importance. Prospective studies considering stroke subtypes, IBD severity and treatments, regions, and other confounding factors are needed to further explore the nature of each association.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022373656.

Evaluating the Causal Association between Inflammatory Bowel Disease and Risk of Atherosclerotic Cardiovascular Disease: Univariable and Multivariable Mendelian Randomization Study

BACKGROUND

Observational studies suggested that inflammatory bowel disease (IBD) (i.e., Crohn's disease [CD] and ulcerative colitis [UC]) is associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD), including coronary artery disease (CAD) and ischemic stroke. However, it is still unclear whether the observed associations causally exist. Thus, we aim to examine the potential effect of IBD, CD, and UC on the risk of CAD and ischemic stroke, using a two-sample Mendelian randomization (MR) study.

METHODS

Genetic instruments for IBD, CD, and UC were retrieved from the latest published genome-wide association studies (GWASs) of European ancestry. GWAS summary data for instrument-outcome associations were gathered from four independent resources: CARDIoGRAMplusC4D Consortium, MEGASTROKE consortium, FinnGen, and UK Biobank. The inverse variance weighted (IVW) method and multiple pleiotropy-robust approaches were conducted and, subsequently, combined in a fixed-effect meta-analysis. Moreover, multivariable MR (MVMR) analysis was conducted to adjust for potential influencing instrumental variables.

RESULTS

The IVW method revealed no causal effect of IBD on the risk of CAD (overall IBD on CAD: OR 1.003, 95%CI 0.982 to 1.025; CD on CAD: OR 0.997, 95%CI 0.978 to 1.016; UC on CAD: OR 0.986, 95%CI 0.963 to 1.010) or the risk of ischemic stroke (overall IBD on ischemic stroke: OR 0.994, 95%CI 0.970 to 1.018; CD on ischemic stroke: OR 0.996, 95%CI 0.979 to 1.014; UC on ischemic stroke: OR 0.999, 95%CI 0.978 to 1.020). The results of the meta-analysis and MVMR remained consistent.

CONCLUSION

Our MR analysis does not support a causal effect of IBD on CAD and ischemic stroke, and previous results from observational studies might be biased through uncontrolled confoundings (such as IBD-specific medications and detection bias, etc.) that warrant further research.