Is multiple sclerosis a risk factor for atherosclerosis?

Carotid intima media thickness in multiple sclerosis: A CLSA study

BACKGROUND

People with multiple sclerosis (MS) have an increased incidence of atherosclerotic disease, including ischemic heart disease and stroke, compared to people without MS even after accounting for risk factors such as hypertension, dyslipidemia, diabetes and smoking. We compared carotid intima media thickness (CIMT), a surrogate of atherosclerosis, in people with MS and in two groups of people without MS (rheumatoid arthritis [RA]; all other participants).

METHODS

We used data from participants in the Canadian Longitudinal Study on Aging (CLSA) who did not have known vascular disease (ischemic heart disease, stroke, transient ischemic attack, peripheral vascular disease) and who underwent carotid ultrasound for assessment of CIMT. We selected participants with MS, RA and controls who did not have MS or RA. Using age and gender-stratified norms for average CIMT in the CLSA, we identified participants in each cohort with a CIMT ≥75th percentile (subclinical atherosclerosis). We also calculated ten-year level of cardiovascular risk using the Framingham Risk Score (FRS). We tested the association between cohort membership (MS, RA, controls) and atherosclerosis using logistic regression, adjusted for FRS, abdominal obesity, excess alcohol intake, education and elevated symptoms of depression. We adjusted all analyses for the stratified sampling design.

RESULTS

We included 78 participants with MS, 364 participants with RA and 13,891 controls. Overall, the average (SE) CIMT was 0.699 (0.002), and this did not differ between cohorts. Logistic regression analyses revealed that cohort membership was not associated with atherosclerosis based on the average CIMT in unadjusted or adjusted models. However, a 1-point higher FRS was associated with 1.032 (95 %CI: 1.021, 1.043) increased odds of atherosclerosis.

CONCLUSION

Average CIMT does not differ between people with MS, people with RA and people without these diseases. Subclinical atherosclerosis as defined by a CIMT ≥75 % is not observed in people with MS at an increased rate beyond what FRS would predict. Further evaluation is needed to determine what mechanisms underlie the increased rates of cardiovascular disease and stroke in MS.

Subclinical atherosclerosis in multiple sclerosis

Background

People with multiple sclerosis (MS) have an increased risk of ischemic heart disease as compared to people without MS after accounting for traditional vascular risk factors.

Objective

We assessed whether subclinical atherosclerosis, an inflammatory disease of arteries, occurs in persons with MS who do not have traditional vascular risk factors, and whether the Framingham Score (FRS) predicted carotid intima media thickness (CIMT) similarly in people with and without MS.

Methods

We recruited participants with and without MS who did not have vascular disease. Participants completed questionnaires, physical assessments, underwent an ultrasound (CIMT), and provided samples for HbA1c and lipid measurements. We defined subclinical atherosclerosis as an average CIMT ≥75th percentile, and tested the association between MS/not-MS, FRS, and atherosclerosis using logistic regression.

Results

We recruited 106 participants with MS 101 without MS. The average (SD) CIMT did not differ between the MS (0.60 [0.11]) and non-MS (0.61 [0.12]) cohorts (p = 0.69), nor did the proportion with atherosclerosis (MS: 11.3% vs. non-MS 13.4%, p = 0.58). On regression analysis a 1-point increase in the FRS was associated with 11% increased odds of having atherosclerosis (95%CI: 1.04, 1.19) but MS was not.

Conclusion

MS was not associated with subclinical atherosclerosis.

Subclinical atherosclerosis in patients with relapsing-remitting multiple sclerosis

BACKGROUND

Multiple sclerosis is an inflammatory disorder of the central nervous system. Inflammation may create high susceptibility to subclinical atherosclerosis. The purpose of this study was to compare subclinical atherosclerosis and the role of inflammatory cytokines between the group of patients with relapsing-remitting multiple sclerosis (RRMS) and healthy controls matched for age and sex.

METHODS

The study group consisted of 112 non-diabetic and non-hypertensive RRMS patients treated with disease modifying drugs (DMD) and the control group was composed of 51 healthy subjects. The common carotid artery (CCA) intima media thickness (IMT) was investigated. Serum levels of risk factors for atherosclerosis and inflammatory cytokines were also determined.

RESULTS

The mean CCA IMT (0.572 ± 0.131 mm vs. 0.571 ± 0.114 mm) did not differ (p > 0.05) between patients and controls. The RRMS patients' CCA IMT was significantly correlated with serum interleukin 6 (IL-6) (p = 0.027), high-sensitivity C-reactive protein (hs-CRP) (p = 0.027), cystatin C (p < 0.0005), glucose (p = 0.031), cholesterol (p = 0.008), LDL (p = 0.021), erythrocyte sedimentation rate (p = 0.001) and triglyceride (p = 0.018) level. We fitted generalized linear models in order to assess the relationship between CCA IMT and IL‑6 with adjustment for sex and age. The obtained results showed that adjusted for age (p < 0.001) and sex (p = 0.048) IL‑6 serum levels statistically significantly (p = 0.009) predict CCA IMT only in the RRMS group.

CONCLUSION

The findings of the present study suggest that when treated with DMD RRMS might not be an independent risk factor for early atherosclerosis presenting with arterial wall thickening; however, the results suggest a significant association of IL‑6 serum levels with CCA IMT only in the RRMS group.

Deciphering crucial genes in multiple sclerosis pathogenesis and drug repurposing: A systems biology approach

This study employed systems biology and high-throughput technologies to analyze complex molecular components of MS pathophysiology, combining data from multiple omics sources to identify potential biomarkers and propose therapeutic targets and repurposed drugs for MS treatment. This study analyzed GEO microarray datasets and MS proteomics data using geWorkbench, CTD, and COREMINE to identify differentially expressed genes associated with MS disease. Protein-protein interaction networks were constructed using Cytoscape and its plugins, and functional enrichment analysis was performed to identify crucial molecules. A drug-gene interaction network was also created using DGIdb to propose medications. This study identified 592 differentially expressed genes (DEGs) associated with MS disease using GEO, proteomics, and text-mining datasets. 37 DEGs were found to be important by topographical network studies, and 6 were identified as the most significant for MS pathophysiology. Additionally, we proposed six drugs that target these key genes. Crucial molecules identified in this study were dysregulated in MS and likely play a key role in the disease mechanism, warranting further research. Additionally, we proposed repurposing certain FDA-approved drugs for MS treatment. Our in silico results were supported by previous experimental research on some of the target genes and drugs. SIGNIFICANCE: As the long-lasting investigations continue to discover new pathological territories in neurodegeneration, here we apply a systems biology approach to determine multiple sclerosis's molecular and pathophysiological origin and identify multiple sclerosis crucial genes that contribute to candidating new biomarkers and proposing new medications.

Retinal Blood Vessel Analysis Using Optical Coherence Tomography (OCT) in Multiple Sclerosis

Background: Both greater retinal neurodegenerative pathology and greater cardiovascular burden are seen in people with multiple sclerosis (pwMS). Studies also describe multiple extracranial and intracranial vascular changes in pwMS. However, there have been few studies examining the neuroretinal vasculature in MS. Our aim is to determine differences in retinal vasculature between pwMS and healthy controls (HCs) and to determine the relationship between retinal nerve fiber layer (RNFL) thickness and retinal vasculature characteristics. Methods: A total of 167 pwMS and 48 HCs were scanned using optical coherence tomography (OCT). Earlier OCT scans were available for 101 pwMS and 35 HCs for an additional longitudinal analysis. Segmentation of retinal vasculature was performed in a blinded manner in MATLAB's optical coherence tomography segmentation and evaluation GUI (OCTSEG) software. Results: PwMS has fewer retinal blood vessels when compared to HCs (35.1 vs. 36.8, p = 0.017). Over the 5.4 year follow up, and when compared to HCs, pwMS has a significant decrease in number of retinal vessels (average loss of -3.7 p = 0.007). Moreover, the total vessel diameter in pwMS does not change when compared to the increase in vessel diameter in the HCs (0.06 vs. 0.3, p = 0.017). Only in pwMS is there an association between lower RNFL thickness and fewer retinal vessel number and smaller diameter (r = 0.191, p = 0.018 and r = 0.216, p = 0.007). Conclusions: Over 5 years, pwMS exhibit significant retinal vascular changes that are related to greater atrophy of the retinal layers.

Biomechanical changes of the common carotid artery and internal jugular vein in patients with multiple sclerosis

PURPOSE

Investigations of the hemodynamic changes of the venous system in patients with multiple sclerosis (MS) have shown contradictory results. Herein, the biomechanical parameters of the internal jugular vein (IJV) and common carotid artery (CCA) of MS patients were extracted and compared to healthy individuals.

METHODS

B-mode and Doppler sequential ultrasound images of 64 IJVs and CCAs of women including 22 healthy individuals, 22 relapsing-remitting multiple sclerosis (RRMS) patients, and 20 primary-progressive multiple sclerosis (PPMS) patients were recorded and processed. The biomechanical parameters of the IJV and the CCA walls during three cardiac cycles were calculated.

RESULTS

The IJV maximum and minimum pressures were higher in the MS patients than in the healthy subjects, by 31% and 19% in RRMS patients and 39% and 24% in PPMS patients. The venous wall thicknesses in RRMS and PPMS patients were 51% and 60% higher than in healthy subjects, respectively. IJV distensibility in RRMS and PPMS patients was 70% and 75% lower, and compliance was 40% and 59% lower than in healthy subjects. The maximum intima-media thicknesses of the CCAs were 38% and 24%, and the minimum intima-media thicknesses were 27% and 23% higher in RRMS and PPMS patients than in healthy individuals, respectively. The shear modulus of CCA walls in RRMS and PPMS patients was 17% and 31%, and the radial elastic moduli were 47% and 9% higher than in healthy individuals.

CONCLUSION

Some physical and biomechanical parameters of the CCA and IJV showed significant differences between MS patients and healthy individuals.

Carotid intima-media thickness measurements in patients with multiple sclerosis

Objectives

The goal of this study was to evaluate the mean carotid intima-media thickness (CIMT) in patients with Multiple Sclerosis (MS).

Methods

In this cross-sectional study, 100 patients with MS were enrolled. Carotid intima-media thickness was measured by Doppler Ultrasonography. The mean CIMT was then compared between different groups of sex, age, body mass index (BMI), medications, and site of the MS plaques in the brain and cervical MRI. In addition, disease duration, annual relapse rate, and Expanded Disability Status Scale (EDSS) were compared between high and normal CIMT groups.

Results

Among 100 patients, Sixty-two percent of the patients were female. The mean age was 35.95 ± 9.32 years. Mean CIMT was 0.38 ± 0.2 mm, and 22% of the patients had abnormal CIMT measures. CIMT was significantly associated with higher age (P = 0.01) and prolonged disease duration (P < 0.001). CIMT was not associated with other disease factors or types of the disease-modifying drug (P > 0.05).

Conclusion

Multiple Sclerosis might be associated with carotid atherosclerotic vascular disease.

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MS is a chronic inflammatory and immune-mediated disease.

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Atherosclerosis is a complex and chronic inflammatory disease, Which is a predictor of cardiovascular disease.

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Intima-media thickness as a marker of atherosclerotic vascular disease can be assessed in Multiple Sclerosis.

Hypoxia in multiple sclerosis; is it the chicken or the egg?

Over the past 50 years, intense research effort has taught us a great deal about multiple sclerosis. We know that it is the most common neurological disease affecting the young-middle aged, that it affects two to three times more females than males, and that it is characterized as an autoimmune disease, in which autoreactive T lymphocytes cross the blood-brain barrier, resulting in demyelinating lesions. But despite all the knowledge gained, a key question still remains; what is the initial event that triggers the inflammatory demyelinating process? While most research effort to date has focused on the immune system, more recently, another potential candidate has emerged: hypoxia. Specifically, a growing number of studies have described the presence of hypoxia (both 'virtual' and real) at an early stage of demyelinating lesions, and several groups, including our own, have begun to investigate how manipulation of inspired oxygen levels impacts disease progression. In this review we summarize the findings of these hypoxia studies, and in particular, address three main questions: (i) is the hypoxia found in demyelinating lesions 'virtual' or real; (ii) what causes this hypoxia; and (iii) how does manipulation of inspired oxygen impact disease progression?

Increased Pro-Thrombotic Platelet Activity Associated with Thrombin/PAR1-Dependent Pathway Disorder in Patients with Secondary Progressive Multiple Sclerosis

Epidemiological studies confirm the high risk of ischemic events in multiple sclerosis (MS) that are associated with increased pro-thrombotic activity of blood platelets. The most potent physiological platelet agonist is thrombin, which activates platelets via cleavage of specific protease-activated receptors (PARs). Our current study is aimed to determine the potential genetics and proteomic abnormalities of PAR1 in both platelets and megakaryocytes, which may have thromboembolic consequences in the course of MS. The obtained results were correlated with the expression level of platelet and megakaryocyte transcripts for APOA1 and A2M genes encoding atherosclerosis biomarkers: apolipoprotein A1 (ApoA1) and α-2-macroglobulin (α2M), respectively. Moreover, PAR1 functionality in MS platelets was assessed by flow cytometry, determining the level of platelet–platelet and platelet–leukocyte aggregates, platelet microparticles and surface expression of P-selectin. As a PAR1 agonist, the synthetic TRAP-6 peptide was used, which made it possible to achieve platelet activation in whole blood without triggering clotting. Comparative analyses showed an elevated level of platelet activation markers in the blood of MS patients compared to controls. The mRNA expression of gene coding α2M was upregulated, whilst ApoA1 was down-regulated, both in platelets and megakaryocytes from MS patients. Furthermore, we observed an increase in both mRNA expression and surface density of PAR1 in platelets and megakaryocytes in MS compared to controls. Both the level of platelet activation markers and PAR1 expression showed a high correlation with the expression of transcripts for APOA1 and A2M genes.