What Links an Increased Cardiovascular Risk and Inflammatory Bowel Disease? A Narrative Review

Mechanistic insight: Linking cardiovascular complications of inflammatory bowel disease

Cardiovascular diseases (CVD) are the leading cause of mortality worldwide despite an aggressive reduction of traditional cardiovascular risk factors. Underlying inflammatory conditions such as inflammatory bowel disease (IBD) increase the risk of developing CVD. A broad understanding of the underlying pathophysiological processes between IBD and CVD is required to treat and prevent cardiovascular events in patients with IBD. This review highlights the commonality between IBD and CVD, including dysregulated immune response, genetics, environmental risk factors, altered gut microbiome, stress, endothelial dysfunction and abnormalities, to shed light on an essential area of modern medicine.

Increased LL37 in psoriasis and other inflammatory disorders promotes LDL uptake and atherosclerosis

Patients with chronic inflammatory disorders such as psoriasis have an increased risk of cardiovascular disease and elevated levels of LL37, a cathelicidin host defense peptide that has both antimicrobial and proinflammatory properties. To explore whether LL37 could contribute to the risk of heart disease, we examined its effects on lipoprotein metabolism and show that LL37 enhanced LDL uptake in macrophages through the LDL receptor (LDLR), scavenger receptor class B member 1 (SR-B1), and CD36. This interaction led to increased cytosolic cholesterol in macrophages and changes in expression of lipid metabolism genes consistent with increased cholesterol uptake. Structure-function analysis and synchrotron small-angle x-ray scattering showed structural determinants of the LL37-LDL complex that underlie its ability to bind its receptors and promote uptake. This function of LDL uptake is unique to cathelicidins from humans and some primates and was not observed with cathelicidins from mice or rabbits. Notably, Apoe-/- mice expressing LL37 developed larger atheroma plaques than did control mice, and a positive correlation between plasma LL37 and oxidized phospholipid on apolipoprotein B (OxPL-apoB) levels was observed in individuals with cardiovascular disease. These findings provide evidence that LDL uptake can be increased via interaction with LL37 and may explain the increased risk of cardiovascular disease associated with chronic inflammatory disorders.

Navigating the Gut-Cardiac Axis: Understanding Cardiovascular Complications in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) presents a complex interplay of chronic inflammation in the gastrointestinal tract and is associated with various extraintestinal manifestations, including cardiovascular complications (CVCs). IBD patients face an elevated risk of CVCs, including coronary artery disease, heart failure, arrhythmias, stroke, peripheral artery disease, venous thromboembolism, and mesenteric ischemia, necessitating comprehensive cardiovascular risk assessment and management. The intricate interplay between chronic inflammation, genetic predisposition, environmental factors, and immune dysregulation likely contributes to the development of CVCs in IBD patients. While the exact mechanisms linking IBD and CVCs remain speculative, potential pathways may involve shared inflammatory pathways, endothelial dysfunction, dysbiosis of the gut microbiome, and traditional cardiovascular risk factors exacerbated by the chronic inflammatory state. Moreover, IBD medications, particularly corticosteroids, may impact cardiovascular health by inducing hypertension, insulin resistance, and dyslipidemia, further amplifying the overall CVC risk. Lifestyle factors such as smoking, obesity, and dietary habits may also exacerbate cardiovascular risks in individuals with IBD. Lifestyle modifications, including smoking cessation, adoption of a heart-healthy diet, regular exercise, and optimization of traditional cardiovascular risk factors, play a fundamental role in mitigating CVC risk. Emerging preventive strategies targeting inflammation modulation and gut microbiome interventions hold promise for future interventions, although further research is warranted to elucidate their efficacy and safety profiles in the context of IBD. Continued interdisciplinary collaboration, advanced research methodologies, and innovative interventions are essential to address the growing burden of CVCs in individuals living with IBD and to improve their long-term cardiovascular outcomes.

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.

Cardiovascular implications of inflammatory bowel disease: An updated review

Emerging data highlights the heightened risk of atherosclerotic cardiovascular diseases (ASCVD) in patients with chronic inflammatory disorders, particularly those afflicted with inflammatory bowel disease (IBD). This review delves into the epidemiological connections between IBD and ASCVD, elucidating potential underlying mechanisms. Furthermore, it discusses the impact of current IBD treatments on cardiovascular risk. Additionally, the cardiovascular adverse effects of novel small molecule drugs used in moderate-to-severe IBD are investigated, drawing parallels with observations in patients with rheumatoid arthritis. This article aims to comprehensively evaluate the existing evidence supporting these associations. To achieve this, we conducted a meticulous search of PubMed, spanning from inception to August 2023, using a carefully selected set of keywords. The search encompassed topics related to IBD, such as Crohn's disease and ulcerative colitis, as well as ASCVD, including coronary artery disease, cardiovascular disease, atrial fibrillation, heart failure, conduction abnormalities, heart blocks, and premature coronary artery disease. This review encompasses various types of literature, including retrospective and prospective cohort studies, clinical trials, meta-analyses, and relevant guidelines, with the objective of providing a comprehensive overview of this critical intersection of inflammatory bowel disease and cardiovascular health.

Cardiovascular Manifestations in Inflammatory Bowel Disease

Inflammatory bowel disease is a group of long-term systemic inflammatory disorders affecting the gastrointestinal tract, including Crohn's disease and ulcerative colitis, which may be associated with an increased risk of developing extraintestinal manifestations, including cardiovascular disease, thereby decreasing the quality of life. Pathophysiological changes associated with inflammatory bowel disease include alterations of the microbiome, endotoxemia, and changes to glucose and lipid metabolism. Inflammatory bowel disease patients have higher carotid intima-media thickness, lower flow-mediated dilatation, and increased carotid-femoral pulse wave velocity, which are markers of elevated cardiovascular risk. In addition, inflammatory bowel disease patients are at an increased risk for developing venous and arterial thrombotic events due to a hypercoagulable state caused by thrombocytosis and coagulation system activation. To reduce the risk of developing cardiovascular disease, lifestyle modifications, such as smoking cessation, dietary changes, and increased physical activity alongside management with appropriate medication, should be considered. This research paper examines how inflammatory bowel disease can influence the risk of cardiovascular complications and the involvement of drug therapy. Methods: PubMed was searched using keywords, such as inflammatory bowel disease, Crohn's disease, ulcerative colitis, cardiovascular disease, pericarditis, thromboembolism, and many more. Relevant literature up to March 2023 has been examined and summarized, which consisted of data from various clinical trials, meta-analyses, retrospective/prospective cohort studies, and current guidelines.

Patients with inflammatory bowel disease are at increased risk of atherothrombotic disease: A systematic review with meta-analysis

AIMS

Patients with inflammatory bowel disease (IBD) are known to be at increased risk for venous thrombosis, while their risk for arterial ischemic events is debated. The purpose of this study was to conduct a systematic review of the published literature on the risk of myocardial infarction (MI) in IBD patients and to identify any potential risk factors.

METHODS

The present study was performed according to PRISMA, with a systematic search on PubMed, Cochrane, and Google Scholar. Risk of MI was the primary end point, while all causes of death and stroke were secondary endpoints. Both univariate and multivariate pooled analysis were performed.

RESULTS

An overall population of 515,455 controls and 77,140 persons with IBD (26,852, 34.8% Crohn's disease, CD and 50,288, 65.2% ulcerative colitis, UC) was included. Mean age was similar across controls and IBD. Persons with CD and UC had lower rates of hypertension (14.5% vs. 14.6% vs. 25%), diabetes (2.9% vs. 5.2% vs. 9.2%) and dyslipidaemia (3.3% vs. 6.5% vs. 16.1%) compared to controls. Smoking did not significantly differ (17% vs. 17.5% vs. 10.6%). Pooled results of multivariate adjustment showed that, after a 5 years-follow-up, both CD and UC were at increased risk of MI (respectively HR 1.36 [1.12-1.64] and HR 1.24 [1.05-1.46]), of death (HR 1.55 [1.27-1.90] and HR 1.29 [1.01-1.64]), and of other CV disease as stroke (HR 1.22 [1.01-1.49] and HR 1.09 [1.03-1.15], all 95% CI).

CONCLUSIONS

Persons with IBD are at increased risk of MI, despite a lower prevalence of the classic risk factors for MI (hypertension, diabetes, dyslipidemia).

Greater Adherence to Cardioprotective Diet Can Reduce Inflammatory Bowel Disease Risk: A Longitudinal Cohort Study

Background: The cardioprotective diet was reported to be associated with several chronic cardiometabolic diseases through an anti-inflammation effect. However, the association between the cardioprotective diet and the risk of inflammatory bowel disease (IBD) was unclear and deserved to be further explored. Methods: We calculated the cardioprotective diet score based on the consumptions of seven common food groups using the validated food frequency questionnaire data in the UK Biobank. Incident IBD was ascertained from primary care data, inpatient data, and the death registry. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between the cardioprotective diet score and the risk of IBD. Results: During a mean follow-up of 12.1 years, we documented 2717 incident IBD cases, including 851 cases of Crohn’s disease and 1866 cases of ulcerative colitis. Compared to participants with a cardioprotective diet score of 0−1, we observed a decreased risk of IBD among participants with cardioprotective diet scores of 3 (HR 0.85, 95% CI 0.73−0.99), 4 (HR 0.84, 95% CI 0.72−0.98), and 5−7 (HR 0.77, 95% CI 0.66−0.89) (p-trend < 0.001). Conclusions: A greater adherence to the cardioprotective diet was associated with a lower risk of IBD. Our finding highlighted the importance of focusing on the cardioprotective diet to prevent IBD.

Inflammatory bowel disease and cardiovascular disease: A two-sample Mendelian randomization analysis

Background

Although epidemiological studies have shown a positive relationship between inflammatory bowel disease (IBD) and risk of cardiovascular disease (CVD) outcomes, a solid causal relationship has not been established. Thus, a two-sample Mendelian randomization (MR) study was conducted to explore the potential causal effect between IBD and CVD outcomes.

Methods

We performed a two-sample MR analysis to analyze the causal effect of the IBD on CVD outcome by using summary-level genome-wide association studies of European descent. The inverse-variance weighted (IVW) method was used as the main MR analysis, with complementary analyses of MR Egger, maximum likelihood, weighted median, penalized weighted media, simple mode, weighted mode, and MR-PRESSO methods. Multiple sensitivity analyses were used to evaluate the robustness of our results.

Results

All P-values were greater than 0.05 in the IVW method, showing no evidence of a causal association between circulating IBD and CVD. Similar results were observed by using other MR methods. No evidence of heterogeneity, pleiotropy, or outlier single-nucleotide polymorphisms was detected. Sensitivity analyses demonstrated the robustness of the results.

Conclusion

The findings of this study provided no evidence to support that IBD has a large effect on risk of CVD outcomes, which is in contrast to many previous observational reports. Further studies are needed to determine the potential mechanism of association identified in observational studies.

Association of Gut Microbial Genera with Heart Rate Variability in the General Japanese Population: The Iwaki Cross-Sectional Research Study

The gut microbiota has become a significant factor associated with health and disease. Although many studies have reported the implications of changes in the gut microbiota on cardiovascular diseases, there are no reports on the relationship between heart rate variability (HRV) and the gut microbiota. Therefore, we investigated the association between gut microbiota abundance and HRV parameters in this cross-sectional study of the general Japanese population. This study included 950 participants of the Iwaki Health Promotion Project who underwent a medical examination in 2019 that included HRV and gut microbiota measurements. At the genus level, multivariate regression analysis showed that higher gut microbial diversity was associated with a higher standard deviation of RR intervals (SDNN). Moreover, a higher SDNN was associated with a higher relative count of Lachnospiraceae incertae sedis. L. incertae sedis abundance was associated with higher HRV parameters such as SDNN, coefficient of variation of RR intervals, low-frequency component power (LF)/high-frequency component power, and LF. In the general Japanese population, higher gut microbial diversity and L. incertae sedis abundance were associated with higher HRV parameters.

Improved Plasma Lipids, Anti-Inflammatory Activity, and Microbiome Shifts in Overweight Participants: Two Clinical Studies on Oral Supplementation with Algal Sulfated Polysaccharide

Seaweed polysaccharides in the diet may influence both inflammation and the gut microbiome. Here we describe two clinical studies with an Ulva sp. 84-derived sulfated polysaccharide—“xylorhamnoglucuronan” (SXRG84)—on metabolic markers, inflammation, and gut flora composition. The first study was a double-blind, randomized placebo-controlled trial with placebo, and either 2 g/day or 4 g/day of SXRG84 daily for six weeks in 64 overweight or obese participants (median age 55 years, median body mass index (BMI) 29 kg/m2). The second study was a randomized double-blind placebo-controlled crossover trial with 64 participants (median BMI 29 kg/m2, average age 52) on placebo for six weeks and then 2 g/day of SXRG84 treatment for six weeks, or vice versa. In Study 1, the 2 g/day dose exhibited a significant reduction in non-HDL (high-density lipoprotein) cholesterol (−10% or −0.37 mmol/L, p = 0.02) and in the atherogenic index (−50%, p = 0.05), and two-hour insulin (−12% or −4.83 mU/L) showed trends for reduction in overweight participants. CRP (C-reactive protein) was significantly reduced (−27% or −0.78 mg/L, p = 0.03) with the 4 g/day dose in overweight participants. Significant gut flora shifts included increases in Bifidobacteria, Akkermansia, Pseudobutyrivibrio, and Clostridium and a decrease in Bilophila. In Study 2, no significant differences in lipid measures were observed, but inflammatory cytokines were improved. At twelve weeks after the SXRG84 treatment, plasma cytokine concentrations were significantly lower than at six weeks post placebo for IFN-γ (3.4 vs. 7.3 pg/mL), IL-1β (16.2 vs. 23.2 pg/mL), TNF-α (9.3 vs. 12.6 pg/mL), and IL-10 (1.6 vs. 2.1 pg/mL) (p < 0.05). Gut microbiota abundance and composition did not significantly differ between groups (p > 0.05). Together, the studies illustrate improvements in plasma lipids and an anti-inflammatory effect of dietary SXRG84 that is participant specific.

Vinculum of Cardiovascular Disease and Inflammatory Bowel Disease: A Narrative Review

Inflammatory bowel disease (IBD), comprising of ulcerative colitis (UC) and Crohn's disease (CrD), is a chronic relapsing-remitting inflammation of the bowel with extraintestinal involvement. Numerous studies published in the last decade have underlined the dangerous cardiovascular disease (CVD) outcomes of IBD, such as ischemic heart disease, heart failure, and stroke, and the need for better therapeutic and prognostic strategies. This article elucidated the pathological web of mechanisms that link IBD with CVD, such as immune dysregulation, endothelial dysfunction, arterial stiffness, and dysbiosis, with a comprehensive review of clinical studies standing for and against the notion in pediatric and adult populations. The current treatment and prevention aim at disease remission and dietary strategies shown to reduce the CVD risk. Exploration of other supplemental preventive and treatment methods, especially during active flares of disease, to reduce the risk of arterial thromboembolic disease (ATED) is the need of the hour.

Where Do We Stand in the Behavioral Pathogenesis of Inflammatory Bowel Disease? The Western Dietary Pattern and Microbiota-A Narrative Review

Despite the increasing knowledge with regard to IBD (inflammatory bowel disease), including ulcerative colitis (UC) and Crohn’s disease (CD), the etiology of these conditions is still not fully understood. Apart from immunological, environmental and nutritional factors, which have already been well documented, it is worthwhile to look at the possible impact of genetic factors, as well as the composition of the microbiota in patients suffering from IBD. New technologies in biochemistry allow to obtain information that can add to the current state of knowledge in IBD etiology.