Biomarkers of asymptomatic carotid stenosis in patients undergoing coronary artery bypass grafting

Homocysteine Combined with Apolipoprotein B as Serum Biomarkers for Predicting Carotid Atherosclerosis in the Oldest-Old

Background

The measurement of serum biomarkers is a promising decision aid in the assessment of atherosclerosis. However, data on the levels and epidemiological distribution of serum biomarkers of carotid atherosclerosis (CAS) in the oldest-old are limited. This study aimed to investigate the characteristics of CAS serum biomarkers in the oldest-old over 80 and explore their predictive value for CAS.

Methods

As part of the China Hainan Centenarian Cohort Study, a total of 1565 individuals over 80 years old were included. Atherosclerosis was assessed by carotid plaque and carotid intima-media thickness. Serum biomarker levels, demographic indicators, and physical examination indicators were detected. Prediction factors correlated to the CAS were explored by logistic regression and verified by receiver operating characteristic curve analysis. Multivariate regression models were fitted, along with subgroup analysis and robustness tests.

Results

Among the oldest-old population, 83.5% (1306) had CAS. In a fully adjusted multivariate logistic regression model, systolic blood pressure (SBP), heart rhythm (HR), serum homocysteine (Hcy), and apolipoprotein B (ApoB) levels were significantly and positively associated with CAS in the oldest-old (PS < 0.001). ROC analysis indicated that the combination of serum Hcy, ApoB, SBP, and HR increased the predictive value for CAS in the oldest-old (area under the curve: 0.856, 95% CI: 0.803-0.879; sensitivity: 81.8%; specificity: 85.9%).

Conclusion

SBP, HR, Hcy and ApoB are independent risk factors for CAS in the oldest-old. The specific set of biomarkers and their combination with other risk markers may be a promising strategy for assessing CAS in the elderly, especially in global aging.

Current Biomarkers for Carotid Artery Stenosis: A Comprehensive Review of the Literature

Carotid artery stenosis (CAS), an atherosclerotic disease of the carotid artery, is one of the leading causes of transient ischemic attacks (TIA) and cerebrovascular attacks (CVA). The atherogenic process of CAS affects a wide range of physiological processes, such as inflammation, endothelial cell function, smooth muscle cell migration and many more. The current gold-standard test for CAS is Doppler ultrasound; however, there is yet to be determined a strong, clinically validated biomarker in the blood that can diagnose patients with CAS and/or predict adverse outcomes in such patients. In this comprehensive literature review, we evaluated all of the current research on plasma and serum proteins that are current contenders for biomarkers for CAS. In this literature review, 36 proteins found as potential biomarkers for CAS were categorized in to the following nine categories based on protein function: (1) Inflammation and Immunity, (2) Lipid Metabolism, (3) Haemostasis, (4) Cardiovascular Markers, (5) Markers of Kidney Function, (6) Bone Health, (7) Cellular Structure, (8) Growth Factors, and (9) Hormones. This literature review is the most up-to-date and current comprehensive review of research on biomarkers of CAS, and the only review that demonstrated the several pathways that contribute to the initiation and progression of the disease. With this review, future studies can determine if any new markers, or a panel of the proteins explored in this study, may be contenders as diagnostic or prognostic markers for CAS.

Influence of Coronary Artery Bypass Grafts on Blood Aminothiols in Patients with Coronary Artery Disease

Coronary artery disease (CAD) and the coronary artery bypass graft (CABG) are associated with a decreased blood glutathione (bGSH) level. Since GSH metabolism is closely related to other aminothiols (homocysteine and cysteine) and glucose, the aim of this study was to reveal the associations of bGSH with glucose and plasma aminothiols in CAD patients (N = 35) before CABG and in the early postoperative period. Forty-three volunteers with no history of cardiovascular disease formed the control group. bGSH and its redox status were significantly lower in CAD patients at admission. CABG had no significant effect on these parameters, with the exception of an increase in the bGSH/hemoglobin ratio. At admission, CAD patients were characterized by negative associations of homocysteine and cysteine with bGSH. All these associations disappeared after CABG. An association was found between an increase in oxidized GSH in the blood in the postoperative period and fasting glucose levels. Thus, CAD is associated with the depletion of the intracellular pool and the redox status of bGSH, in which hyperhomocysteinemia and a decrease in the bioavailability of the extracellular pool of cysteine play a role. The present study indicates that CABG causes disruptions in aminothiol metabolism and induces the synthesis of bGSH. Moreover, glucose becomes an important factor in the dysregulation of GSH metabolism in CABG.

A systematic review of cost-effectiveness analyses on endovascular thrombectomy in ischemic stroke patients

OBJECTIVE

The objective of this study was to examine the published cost-effectiveness analyses (CEAs) on endovascular thrombectomy (EVT) in acute stroke patients, with a particular focus on the practice of accounting for costs and utilities.

METHODS

We conducted a systematic review of published CEAs on EVT in acute stroke patients from 1/1/2009 to 10/1/2019. Published CEAs were searched in Ovid Embase, Ovid MEDLINE, and Web of Science. Cost or comparative effectiveness analyses were excluded. Risk of bias and quality assessment was based on the Consolidated Health Economic Evaluation Reporting Standard checklist.

RESULTS

Twenty-one studies were included in the final analysis, from the USA, Canada, Europe, Asia, and Australia. They all concluded EVT to be cost-effective, but with significant variations in methodology. Fifteen studies employed a long-term horizon (> 20 years), while only 11 incorporated risk of recurrent strokes. The willingness-to-pay (WTP) threshold varied from $10,000/quality-adjusted life year (QALY) to $120,000/QALY, with $50,000/QALY and $100,000/QALY being the most commonly used. Five studies undertook a societal perspective, but only one accounted for indirect costs. Seventeen studies based outcomes on 90-day modified Rankin Scale (mRS) scores, and 9 of these 17 studies grouped outcomes by mRS 0-2 and 3-5. Among these 9 studies, the range of QALY score reported for mRS 0-2 was 0.71-0.85 QALY, and that of mRS 3-5 was 0.21-0.40.

CONCLUSIONS

Our study reveals significant heterogeneity in previously published thrombectomy CEAs, highlighting need for better standardization in future CEAs.

KEY POINTS

• All included studies concluded thrombectomy to be cost-effective, from both long- and short-term perspectives. • Only 5 out of 22 studies undertook a societal perspective, and only 1 accounted for indirect costs. • The range of value for mRS 0-2 was 0.71-0.85 quality-adjusted life year (QALY) and 0.21-0.40 QALY for mRS 3-5.

Lipoprotein(a), Immunity, and Inflammation in Polyvascular Atherosclerotic Disease

Background and aims: lipoprotein(a) (Lp(a)) is a genetically determined risk factor for coronary artery disease and its complications, although data on the association with other vascular beds and the severity of atherosclerosis is limited. The aim of this study was to evaluate the association of atherosclerosis of various vascular beds with Lp(a), as well as its autoantibodies and generalized inflammatory markers. Material and methods: this study included 1288 adult patients with clinical and imaging examination of three vascular beds (coronary, carotid, and lower limb arteries). Patients were categorized according to the number of affected vascular beds (with at least one atherosclerotic stenosis ≥50%): 0 (n = 339), 1 (n = 470), 2 (n = 315), 3 (n = 164). We assessed blood cell count, lipid profile, C-reactive protein, circulating immune complexes, Lp(a), and its autoantibodies. Results: the number of affected vascular beds was associated with an increasing level of Lp(a) and a lower level of IgM autoantibodies to Lp(a). Hyperlipoproteinemia(a) (Lp(a) ≥ 30 mg/dL) was detected more frequently in patients with atherosclerosis. In logistic regression analysis adjusted for age, sex, hypertension, type 2 diabetes, and smoking, an elevated Lp(a) level was independently associated with stenotic atherosclerosis and lesion severity. There was a positive association of the number of affected vascular beds with C-reactive protein (r = 0.21, p < 0.01) and a negative association with circulating immune complexes (r = −0.29, p < 0.01). The neutrophil-to-lymphocyte ratio was significantly higher and the lymphocyte-to-monocyte ratio was significantly lower in patients with atherosclerosis compared to the controls (p < 0.01). Conclusion: Lp(a), C-reactive protein, circulating immune complexes, and neutrophil-to-lymphocyte ratio are associated with the stenotic atherosclerosis of different vascular beds. Lp(a) levels increase and IgM autoantibodies to Lp(a) decrease with the number of affected vascular beds.

Carotid intraplaque neovascularization predicts atherosclerotic renal artery stenosis in patients with carotid artery stenosis

BACKGROUND AND AIMS

This study aimed to examine whether intraplaque neovascularization (IPN) of carotid plaques, as characterized by contrast-enhanced ultrasound (CEUS), is associated with atherosclerotic renal artery stenosis (ARAS) in patients with normal kidney function.

METHODS AND RESULTS

We investigated carotid IPN using CEUS in 198 consecutive patients with normal kidney function with and without ARAS. IPN was graded on the basis of the presence and location of microbubbles within each plaque (0, no visible microbubbles in the plaque; 1, moderate microbubbles confined to the shoulder and/or adventitial side of the plaque; and 2, extensive microbubbles throughout the plaque). The grades of each plaque were averaged to obtain an overall score per patient. ARAS was determined angiographically. We found that a higher CEUS-assessed carotid IPN score was associated with ARAS (Odd Ratio, OR: 7.281; 95% Confidence Interval, 95% CI: 3.246-16.336; P < 0.001). Furthermore, an IPN score >1.75 predicted severe stenosis with a sensitivity of 81% and specificity of 58%. Compared with using the IPN score alone, the addition of the homocysteine (HCY) cutoff value (>22.5 mmol/L) resulted in a stronger predictive value (Area Under Curve, AUC: 0.893 vs 0.834; P < 0.001) for severe ARAS.

CONCLUSION

Carotid plaque neovascularization combined with HCY levels is predictive of severe ARAS in patients with normal kidney function. CEUS-assessed carotid IPN is clinically useful for stratification of ARAS in patients with normal kidney function.

[Lipoprotein(а) Level, Apolipoprotein(а) Polymorphism аnd Autoаntibodies Against Lipoprotein(а) in Patients with Stenotic Cаrotid Atherosclerosis]

Аim. Comparative assessment of respiratory indicators according to multifunctional monitoring (PFM) with the recommended standard for a complete polysomnographic study and an assessment of the effect of blood pressure (BP) measurements in PFM on sleep quality. Triаls on the аssociаtion of Lp(а) and cаrotid аtherosclerosis аre limited. The аim of the study wаs to investigаte the аssociаtion of Lp(а), аpolipoprotein(а) [apo(а)] polymorphism аnd аutoаntibodies to Lp(а) with stenotic (≥50%) cаrotid аtherosclerosis in dependence on CHD presence. Materials and methods. The study included 785 pаtients аt the аge from 21 to 92 with dаtа of instrumentаl exаmination of coronаry, cаrotid аnd lower limbs аrteries. Stenotic cаrotid аtherosclerosis wаs diаgnosed in 447 pаtients who were divided into two groups depending on presence (n=344) or аbsence (n=103) of CHD. The control group comprised of 338 pаtients without stenotic аtherosclerosis of coronаry, cаrotid аnd lower limbs аrteries. In the blood serum of pаtients levels of Lp(а), аutoаntibodies to Lp(а) were determined аnd аlso аpo(а) phenotyping wаs conducted. Results. There were more mаles, higher аverаge аge аnd frequency of hypertension, type 2 diаbetes mellitus, smoking, Lp(а) concentrаtion (mediаn [interquаrtile rаnge]): 30 [11; 63] vs. 14 [5; 30] mg/dl, p&lt;0.01) in the group with stenotic cаrotid аtherosclerosis in compаrison with control group. Besides, Lp(а) level wаs higher in CHD subgroup thаn in pаtients with stenotic cаrotid аtherosclerosis without CHD: 32 [12; 72] vs. 24 [8; 50] mg/dl, respectively, p=0.01. Elevаted (≥30 mg/dl) Lp(а) level, low moleculаr weight аpolipoprotein(а) [(LMW аpo(а)] phenotype were аssociаted with stenotic cаrotid аtherosclerosis (odds rаtio (OR) 2.9; 95% confidence intervаl (CI) 2.1-4.0, p&lt;0.01 аnd OR 2.3; 95% CI 1.6-3.4, p&lt;0.01, respectively). Logistic regression аnаlysis showed independent аssociаtion of elevаted Lp(а) level аnd LMW аpo(а) phenotype with stenotic cаrotid аtherosclerosis both in the presence аnd absence of CHD. The level of IgM аutoаntibodies to Lp(а) wаs higher in control group thаn in pаtients with stenotic cаrotid аtherosclerosis, p=0.02. Conclusion The level of Lp(a) ≥30 mg/dl and low molecular weight phenotype of aprotein(a) are predictors of stenotic atherosclerosis CA, regardless of the presence of coronary heart disease and other risk factors, while a reverse relationship was found between the level of autoantibodies of the IgM class against Lp(a) and the severity of atherosclerosis CA.

The urgent need for contemporary clinical trials in patients with asymptomatic carotid stenosis

Asymptomatic extracranial internal carotid artery atherosclerotic stenosis increases with age and is more common in men. Studies performed more than 2 decades ago showed that carotid endarterectomy reduced the rate of stroke in carefully selected patients with asymptomatic carotid stenosis compared with medical therapy in the long term. Those trials were completed more than 20 years ago and with advances in the treatment of atherosclerotic disease, the question has been raised to as to whether endarterectomy is still of value for patients with asymptomatic narrowing. Perioperative risk of carotid revascularization procedures has also declined. Due to improvements in both medical and surgical treatments for carotid artery stenosis, it is timely to reevaluate the efficacy of carotid intervention relative to medical treatment for patients with asymptomatic stenosis.

Homocysteine and Its Relationship to Asymptomatic Carotid Stenosis in a Chinese Community Population

Little is known about the association between homocysteine (Hcy) and asymptomatic CAS in the healthy population. The purpose of this study was to investigate the relationship between Hcy levels and asymptomatic CAS in a Chinese community population. The current study included 5393 participants who were age of 40 years or older, and free of stroke, transient ischemic attack, and coronary artery disease. Demographic and clinical variables were investigated, and the presence of CAS was assessed by Color Doppler Ultrasound. A multivariate logistic regression was used to examine the association between Hcy levels and asymptomatic CAS. 361 (6.69%) participants were diagnosed with asymptomatic CAS, who had higher Hcy levels compared with those without (p-value for trend = 0.0001). After adjusting other possible risk factors, Hcy > 19.3μmol/L was considered as an independent indicator of asymptomatic CAS (OR 1.53, 95%CI 1.05–2.23; p-value for trend = 0.0265), but with a difference between participants with diabetes and without [OR (95%CI): 2.89(1.02–8.22) vs. 1.42(0.95–2.12); P interaction < 0.05]. In this large-population, community-based study, Hcy is an independent indicator of asymptomatic CAS, especially in patients with diabetes.

Medical and Revascularization Therapies for Asymptomatic Carotid Stenosis

Asymptomatic internal carotid artery stenosis increases with age and is more common in men. Carotid endarterectomy and stenting have reduced stroke rates in patients with asymptomatic carotid stenosis in clinical trials. A variety of risk stratification methods are available for selection of patients with carotid stenosis for revascularization. In the past decade, there is increasing evidence that the rate of stroke declined with the use of aggressive multi-modal medical therapy. These developments have led to new clinical trials to compare revascularization versus aggressive medical therapy in patients with asymptomatic carotid stenosis.

Subclinical carotid artery disease and plasma homocysteine levels in patients with hypertension

Information on the association between homocysteine (Hcy) levels and subclinical carotid artery disease is limited. We investigated the relationship of plasma Hcy concentration with carotid artery plaques and intima-media thickness (IMT) in patients with hypertension. In 486 essential hypertensive patients who underwent ultrasound examination of the carotid arteries, we measured plasma levels of Hcy, vitamin B12, folate, and C-reactive protein. Plaques were detected in 34% of the study patients. Plasma Hcy levels were significantly greater in hypertensive patients with evidence of carotid plaques than patients without carotid plaques. Carotid IMT progressively increased across quartiles of plasma Hcy levels. Multivariate regression showed that carotid IMT was independently related with age, blood pressure, C-reactive protein, and Hcy levels. In a logistic regression, age, blood pressure, triglyceride, and Hcy independently predicted the presence of carotid plaques. Thus, elevated plasma Hcy levels are associated with asymptomatic carotid disease in hypertensive patients suggesting a role of Hcy in the development and progression of carotid atherosclerosis in these patients.

Co-prevalence of carotid stenosis and coronary artery disease in Chinese patients with paroxysmal atrial fibrillation

OBJECTIVES

To investigate the co-prevalence of coronary artery disease (CAD) and carotid stenosis and to determine predictors related to CAD in Chinese patients with paroxysmal atrial fibrillation (PAF), presenting without previously diagnosed or excluded CAD.

METHODS

Consecutive patients with PAF were recruited. CAD was evaluated using multislice computed tomography. Intima-media thickness (IMT) of the carotid artery was evaluated via ultrasonography.

RESULTS

A total of 62/192 (32.3%) patients had CAD. Carotid stenosis was observed in 26/192 (13.5%) patients. The co-prevalence of carotid stenosis and CAD was 7.8% (15/192). The prevalence of carotid stenosis was 8.5%, 16.7%, 25.0%, and 41.7% in patients with zero-, one-, two-, and three-vessel CAD, respectively. Diabetes mellitus, maximal IMT and hyperhomocysteinaemia were independently related to the presence of CAD.

CONCLUSIONS

The prevalence of CAD was 32.3% in Chinese patients with PAF. Carotid stenosis and CAD co-occurred in 7.8% of patients, and the prevalence of carotid stenosis correlated with the severity of CAD. Screening of carotid stenosis is recommended, especially in patients with PAF and multivessel CAD.

Hyperhomocysteinemia is one of the risk factors associated with cerebrovascular stiffness in hypertensive patients, especially elderly males

Hyperhomocystemia has been reported to be associated with cardiovascular disease, especially stroke. The resistive index (RI) estimated by carotid ultrasound is an established variable for estimating the risk of cerebral infarction. The aim of this study was to evaluate the relationship between homocysteine concentration and carotid RI, a marker of cerebral vascular resistance in essential hypertensive patients. We measured serum total homocysteine and carotid RI in 261 patients. Multiple linear regression analysis was used to determine the association of homocysteine with carotid RI and intima media thickness (IMT). Age, sex, BMI, systolic blood pressure (SBP), homocysteine, total cholesterol, high density lipoprotein-cholesterol (HDL-C), uric acid, CRP, HbA1c, estimated glomerular filtration rate, and use of antihypertensive agents were included as independent variables. Age, sex, use of antihypertensive agents, HDL-C and homocysteine levels were shown to be significant predictors of carotid RI, but not IMT. Multiple regression analysis in men older than 65 years showed homocysteine and SBP were associated significantly with carotid RI. In elderly male patients, homocysteine was the strongest predictor of carotid RI (B = 0.0068, CI = 0.0017-0.0120, P = 0.011) in the multivariate model. In conclusion, hyperhomocysteinemia is associated with carotid RI, a surrogate marker of cerebral vascular resistance, especially in elderly men.

Biomarkers for stroke

Background

Major stroke clinical trials have failed during the past decades. The failures suggest the presence of heterogeneity among stroke patients. Biomarkers refer to indicators found in the blood, other body fluids or tissues that predicts physiologic or disease states, increased disease risk, or pharmacologic responses to a therapeutic intervention. Stroke biomarkers could be used as a guiding tool for more effective personalized therapy.

Main Contents

Three aspects of stroke biomarkers are explored in detail. First, the possible role of biomarkers in patients with stroke is discussed. Second, the limitations of conventional biomarkers (especially protein biomarkers) in the area of stroke research are presented with the reasons. Lastly, various types of biomarkers including traditional and novel genetic, microvesicle, and metabolomics-associated biomarkers are introduced with their advantages and disadvantages. We especially focus on the importance of comprehensive approaches using a variety of stroke biomarkers.

Conclusion

Although biomarkers are not recommended in practice guidelines for use in the diagnosis or treatment of stroke, many efforts have been made to overcome the limitations of biomarkers. The studies reviewed herein suggest that comprehensive analysis of different types of stroke biomarkers will improve the understanding of individual pathophysiologies and further promote the development of screening tools for of high-risk patients, and predicting models of stroke outcome and rational stroke therapy tailored to the characteristics of each case.

Cardiovascular physiology in premotor Parkinson's disease: a neuroepidemiologic study

Changes in cardiovascular physiology in Parkinson's disease (PD) are common and may occur prior to diagnostic parkinsonian motor signs. We investigated associations of electrocardiographic (ECG) abnormalities, orthostasis, heart rate variability, and carotid stenosis with the risk of PD diagnosis in the Cardiovascular Health Study, a community-based cohort of older adults. ECG abnormality, orthostasis (symptomatic or asymptomatic), heart rate variability (24-hour Holter monitoring), and any carotid stenosis (≥1%) by ultrasound were modeled as primary predictors of incident PD diagnosis using multivariable logistic regression. Incident PD cases were identified by at least 1 of the following: self-report, antiparkinsonian medication use, and ICD-9. If unadjusted models were significant, they were adjusted or stratified by age, sex, and smoking status, and those in which predictors were still significant (P ≤ .05) were also adjusted for race, diabetes, total cholesterol, low-density lipoprotein, blood pressure, body mass index, physical activity, education level, stroke, and C-reactive protein. Of 5888 participants, 154 incident PD cases were identified over 14 years of follow-up. After adjusting models with all covariates, those with any ECG abnormality (odds ratio [OR], 1.45; 95% CI, 1.02-2.07; P = .04) or any carotid stenosis (OR, 2.40; 95% CI, 1.40-4.09; P = .001) at baseline had a higher risk of incident PD diagnosis. Orthostasis and heart rate variability were not significant predictors. This exploratory study suggests that carotid stenosis and ECG abnormalities occur prior to motor signs in PD, thus serving as potential premotor features or risk factors for PD diagnosis. Replication is needed in a population with more thorough ascertainment of PD onset.

The ocular pulse amplitude as a noninvasive parameter for carotid artery stenosis screening: a test accuracy study

PURPOSE

To investigate a potential correlation between the ocular pulse amplitude (OPA; i.e., the intraocular pressure difference between the systolic and diastolic phases of the heartbeat) and the severity of carotid artery stenosis (CAS) and to test its role as a screening parameter for CAS during routine ophthalmic examination.

DESIGN

Test accuracy study.

PARTICIPANTS

Patients referred for color duplex ultrasound examination of the extra- and intracranial cerebral arteries were enrolled consecutively.

METHODS

We measured OPA on both eyes by dynamic contour tonometry. Multivariate analyses were performed with risk factors for CAS (age, total cholesterol, low-density lipoprotein, and triglycerides) to compare the diagnostic value of OPA measurements with other non- or minimally invasive screening parameters.

MAIN OUTCOME MEASURES

The difference between OPA measurements in patients with no (<50%) and patients with severe CAS (>70%) as well as the value of OPA measurements to predict the severity of CAS taking further risk factors of CAS into consideration.

RESULTS

One hundred thirty-four eyes of 67 patients (25 women, 42 men) with a mean age of 67±13 years (range, 25-87) were included. The means of the OPA values of those patients showing no CAS (<50%) differed significantly (P = 0.036) from those with a stenosis of ≥70%. The multivariate model produced a statistically significant odds ratio (0.46; P = 0.007) for CAS of ≥70%.

CONCLUSIONS

The results of the present study provide proof of principle that the OPA is reduced in patients with CAS and may be used as a noninvasive, inexpensive, readily available, and unconfounded screening parameter to detect CAS and possibly to reduce the incidence of stroke.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any of the materials discussed in this article.