Cardiovascular disease in patients with inflammatory bowel disease: An issue in no guidelines land

Growth differentiation factor-15 serum concentrations reflect disease severity and anemia in patients with inflammatory bowel disease

BACKGROUND

Population of patients with inflammatory bowel disease (IBD) is burdened by various extraintestinal manifestations which substantially contribute to greater morbidity and mortality. Growth-differentiation factor-15 (GDF-15) is often over-expressed under stress conditions, such as inflammation, malignancies, heart failure, myocardial ischemia, and many others.

AIM

To explore the association between GDF-15 and IBD as serum concentrations of GDF-15 were shown to be an independent predictor of poor outcomes in multiple diseases. An additional aim was to determine possible associations between GDF-15 and multiple clinical, anthropometric and laboratory parameters in patients with IBD.

METHODS

This cross-sectional study included 90 adult patients diagnosed with IBD, encompassing both Crohn's disease (CD) and ulcerative colitis (UC), and 67 healthy age- and sex-matched controls. All patients underwent an extensive workup, including colonoscopy with subsequent histopathological analysis. Disease activity was assessed by two independent gastroenterology consultants specialized in IBD, employing well-established clinical and endoscopic scoring systems. GDF-15 serum concentrations were determined following an overnight fasting, using electrochemiluminescence immunoassay.

RESULTS

In patients with IBD, serum GDF-15 concentrations were significantly higher in comparison to the healthy controls [800 (512-1154) pg/mL vs 412 (407-424) pg/mL, P < 0.001], whereas no difference in GDF-15 was found between patients with CD and UC [807 (554-1451) pg/mL vs 790 (509-956) pg/mL, P = 0.324]. Moreover, multiple linear regression analysis showed that GDF-15 levels predict CD and UC severity independent of age, sex, and C-reactive protein levels (P = 0.016 and P = 0.049, respectively). Finally, an association between GDF-15 and indices of anemia was established. Specifically, negative correlations were found between GDF-15 and serum iron levels (r = -0.248, P = 0.021), as well as GDF-15 and hemoglobin (r = -0.351, P = 0.021). Accordingly, in comparison to IBD patients with normal hemoglobin levels, GDF-15 serum levels were higher in patients with anemia (1256 (502-2100) pg/mL vs 444 (412-795) pg/mL, P < 0.001).

CONCLUSION

For the first time, we demonstrated that serum concentrations of GDF-15 are elevated in patients with IBD in comparison to healthy controls, and the results imply that GDF-15 might be involved in IBD pathophysiology. Yet, it remains elusive whether GDF-15 could serve as a prognostic indicator in these patients.

Impact of Inflammatory Bowel Disease (IBD) and IBD Medications on Risk of Hyperlipidemia and in vitro Hepatic Lipogenic-Related Gene Expression: A Population-Based Cohort Study

Patients with inflammatory bowel disease (IBD) present a higher risk of developing cardiovascular diseases (CVDs) due to chronic inflammation, which plays an essential role in atherogenesis. Hyperlipidemia is another risk factor for CVDs; however, the association between IBD, IBD medications, and hyperlipidemia remains controversial. We conducted a nationwide, population-based, retrospective, cohort study to examine the effect of IBD and IBD medications on the risk of developing hyperlipidemia. The effects of IBD medications on the expression of lipogenesis-related hepatic genes were also evaluated. We obtained data from the Longitudinal Health Insurance Database of Taiwan from patients with new-onset IBD and a comparison cohort of patients without IBD. A Cox proportional hazards regression model was used to analyze the difference in the risk of developing hyperlipidemia between the two cohorts. We also examined the influence of IBD medications on the expression of lipogenesis-related hepatic genes. After adjusting for comorbidities and confounding factors, the case group (N = 14,524) had a higher risk for hyperlipidemia than the control group (N = 14,524) [adjusted hazards ratio (aHR), 2.18]. Patients with IBD that did not receive IBD medications exhibited a significantly higher risk of hyperlipidemia (aHR, 2.20). In those treated with IBD medications, the risk of developing hyperlipidemia was significantly lowered than those without such medications (all aHR ≤ 0.45). Gene expression analysis indicated that IBD medications downregulated the expression of lipogenesis-related genes. Screening blood lipids in IBD patients is needed to explore the specific role and impact of IBD medications in the development of CVD.

Cardiovascular Risk Assessment and Impact of Medications on Cardiovascular Disease in Inflammatory Bowel Disease

There is increased risk of cardiovascular disease in patients with chronic inflammatory disorders such as rheumatoid arthritis, psoriatic arthritis, and systemic lupus erythematosus. Studies have shown association between cardiovascular disease (eg, myocardial infarction, heart failure, stroke) and inflammatory bowel disease. Medications such as infliximab and adalimumab (monoclonal antibodies to tumor necrosis factor α) may help decrease the inflammatory burden and cardiovascular risk; however, there have been reports of hypertriglyceridemia and worsening of moderate to severe heart failure with these medications. Janus kinase inhibitors, such as tofacitinib, have been associated with hyperlipidemia and thromboembolism. We aim to discuss clinical and imaging modalities to assess cardiovascular risk in inflammatory bowel disease patients and review the role of various medications with respect to cardiovascular disease in this population.

Cardiovascular Manifestations of Inflammatory Bowel Disease: Pathogenesis, Diagnosis, and Preventive Strategies

Inflammatory bowel disease (IBD) refers to a group of chronic inflammatory diseases that targets mainly the gastrointestinal tract. The clinical presentation of IBD includes both gastrointestinal manifestations and extraintestinal manifestations (EIM). The reported cardiovascular manifestations in IBD patients include pericarditis, myocarditis, venous and arterial thromboembolism, arrhythmias, atrioventricular block, heart failure, endocarditis, valvulopathies, and Takayasu arteritis. The aim of this article is to review the available literature about the possible pathogenic mechanisms and determine preventive measures capable of reducing the incidence and severity of the cardiovascular manifestations. In IBD patients, the incidence of cardiovascular manifestations is low, but higher than that in the general population. Therefore, clinicians should pay attention to any new modification that might indicate cardiovascular involvement in IBD patients, and they should consider chronic inflammatory diseases in patients with cardiac conditions without an evident cause. Considering the role of inflammation in the development of cardiovascular manifestations, the management should include prevention of flares and maintenance of remission for as long as possible. Preventive measures should also include active screening and strict control of the cardiovascular risk factors in all IBD patients.

Inflammatory Bowel Disease and Risk of Ischemic Heart Disease: An Updated Meta-Analysis of Cohort Studies

Background

Several immune‐mediated diseases have been shown to be associated with an increased risk of cardiovascular disease. However, studies evaluating the association between inflammatory bowel disease and risk of cardiovascular disease reported inconsistent results. We assessed the association between inflammatory bowel disease and risk of ischemic heart disease in a meta‐analysis of cohort studies.

Methods and Results

We conducted a literature search of PubMed and Embase up to October 2016 to identify relevant studies. The summary relative risks were calculated using the random‐effects models. To explore the source of heterogeneity, we performed subgroup and sensitivity analysis. We included 10 cohort studies that satisfied our inclusion criteria. Patients with inflammatory bowel disease were associated with an increased risk of ischemic heart disease (relative risk: 1.244; 95% CI, 1.142–1.355). Considerable heterogeneity was observed. Crohn's disease showed a significantly increased risk of ischemic heart disease (relative risk=1.243; 95% CI, 1.042–1.482) and a positive association was also observed in ulcerative colitis (relative risk=1.206; 95% CI, 1.170–1.242).

Conclusions

Based on meta‐analysis of cohort studies, we found an increased risk of ischemic heart disease in patients with inflammatory bowel disease. Large long‐term prospective studies are warranted to confirm our results.

Psoriasis as a human model of disease to study inflammatory atherogenesis

Inflammation is known to play a significant role in the process of atherogenesis and cardiovascular disease (CVD). Indeed, patients with chronic inflammatory diseases are at increased risk for cardiovascular events. However, the mechanisms linking chronic inflammation and CVD remain poorly understood. Psoriasis, a chronic inflammatory skin disease associated with a greater risk of early cardiovascular events, provides a suitable human model to study the pathophysiology of inflammatory atherogenesis in humans. Additionally, cytokines such as TNF-α, IL-17A, and other immune pathways are the common links between the pathogenesis of psoriasis and atherosclerosis, and hence the approved treatments for psoriasis, which include selective cytokine inhibition (e.g., anti-TNF, anti-IL-17A, and anti-IL-12/23) and immune modulation (e.g., methotrexate or cyclosporine), provide an opportunity to examine the effect of modulating these pathways on atherogenesis. We have been using this human model in a large, prospective cohort study, and this review summarizes our approach and results of using this human model to study inflammatory atherogenesis. Specifically, we review simultaneous multimodal imaging of several vascular beds using ¹⁸fludeoxyglucose positron emission tomography/computed tomography, ¹⁸fludeoxyglucose positron emission tomography/MRI, and coronary computed tomography angiography as well as cardiovascular biomarkers to better understand how modulation of inflammation may impact vascular diseases.