Carotid intima-media thickness and cardiovascular disease risk prediction

Glucose metabolism status modifies the relationship between lipoprotein(a) and carotid plaques in individuals with fatty liver disease

BACKGROUND AND AIMS

Glucose and lipoprotein(a) [Lp(a)] have been recognized risk factors for atherosclerosis. The impact of both factors on fatty liver patients has not been studied. The aim of this study is to explore the role of high-level Lp(a) and different glucose metabolism statuses on carotid plaques in fatty liver patients.

METHODS

We selected 4,335 fatty liver patients in this cross-sectional study. The diagnosis of fatty liver disease and carotid plaques was made by ultrasound. Participants were divided into four groups based on glucose metabolism status (normal glucose regulation [NGR], lower bound of impaired fasting glucose [IFG-L], higher bound of impaired fasting glucose [IFG-H], diabetes mellitus [DM]) and then categorized into 12 subgroups according to Lp(a) concentrations. The association between variables was estimated by odds ratio (OR).

RESULTS

Carotid plaques were present in 1,613 (37.2%) fatty liver patients. Lp(a)≥30 mg/dL was associated with high risk of carotid plaques in those patients with IFG-L, IFG-H and DM (OR 1.934 [95% CI 1.033-3.618], 2.667 [1.378-5.162], 4.000 [2.219-7.210], respectively; p<0.05). Fatty liver patients with DM plus Lp(a)<10 mg/dL and 10≤Lp(a)<30 mg/dL were more vulnerable to carotid plaques (OR 1.563 [95% CI 1.090-2.241], 1.930 [1.279-2.914]), respectively, p<0.05).

CONCLUSIONS

Our study first suggested that high-level Lp(a) may raise the risk of carotid plaques in fatty liver patients with not only diabetes but also IFG, manifesting that Lp(a) may be helpful for the early discovery of subclinical atherosclerosis in fatty liver patients with impaired glucose metabolism.

Preclinical carotid atherosclerosis as an indicator of polyvascular disease: a narrative review

Carotid atherosclerotic lesions are correlated with atherosclerotic deterioration of the arterial wall in other vascular territories and with cardiovascular events. The detection of pre-symptomatic carotid lesions like intima-media thickness (IMT) and asymptomatic carotid plaques is possible by non-invasive ultrasound duplex scanning. Current measurement guidelines suggest an average measurement of IMT within 10 mm of the segment of the common carotid artery. The thickening of intima-media appears in a long subclinical period of atherosclerosis. Therefore, the determination of IMT has emerged as one of the methods for determining early structural deterioration of the arterial wall. A close interrelationship was shown between IMT and risk factors of atherosclerosis, their duration, and intensity. Different studies demonstrated that increased IMT is a powerful predictor of coronary, cerebrovascular, and peripheral arterial occlusive disease and their complication. A recent meta-analysis indicated a minimal improvement in the risk estimation of cardiovascular events after adding IMT to the Framingham Risk Score. These findings influenced the latest ACC/AHA guidelines which again recommend the use of carotid IMT measurement for individual risk assessment. The presence of atherosclerotic plaques indicates that the atherosclerotic process is already ongoing. The findings of different studies are equivocal that carotid plaques independently predict cardiovascular events and improve risk predictions for coronary artery disease when added to the Framingham Risk Score. However, besides the size of plaque and grade of stenosis, the structure of plaque calcification, vascularization, lipid core, and the surface of plaques are important indicators of related risks for cardiovascular events.

Association of Hepatic Steatosis Index and Fatty Liver Index with Carotid Atherosclerosis in Type 2 Diabetes

Background/aim: Previous studies have suggested that the hepatic steatosis index (HSI) and fatty liver index (FLI) can be used as a predictor of non-alcoholic fatty liver disease (NAFLD). The aim of our study was to determine whether non-invasive indices of hepatic steatosis (HSI and FLI) are associated with carotid atherosclerosis in type 2 diabetes mellitus (T2DM). Methods: This was a cross-sectional study conducted in the T2DM patients (n=768). Carotid intima-media thickness (CIMT) was measured by the Color Doppler ultrasound. The HSI was calculated based on gender, body mass index (BMI), and transaminases level. The FLI was based on BMI, waist circumference (WC), triacylglycerols (TG) and g-glutamyl transferase (GGT). Results: Raised HSI and FLI levels was associated with increased CIMT levels in T2DM patients. Patients with greater CIMT had higher HSI (39.10 ± 5.70 vs 36.10 ± 4.18, P < 0.001) and FLI (46.35 (29.96, 65.54) vs 36.93 (18.7, 57.93), P < 0.001) than those with lower CIMT. Subjects with existing carotid plaque had higher HSI (38.28 ± 5.63 vs 35.69 ± 3.45 P < 0.001) and FLI (47.41 (27.77, 66.62) vs 37.19 (17.71, 51.78), P < 0.001) accordingly. HSI (r = 0.343, P < 0.001) and FLI (r = 0.184, P < 0.001) were positively related with the CIMT. In the linear regression, after full adjustment metabolic risk factors, smoking, and measures of insulin resistance, HSI and FLI were independently associated with CIMT (HSI: β = 0.011, FLI: β = 0.001, all P < 0.01). Further, logistic regression analyses showed that higher HSI and FLI had an impact on the risk for carotid atherosclerosis [HSI: OR (95%CI): 1.174 (1.123-1.228), FLI: OR (95%CI): 1.011(1.004-1.019), all P < 0.01]. Overall, increasing values of HSI and FLI were associated with CIMT (P < 0.05) significantly across different categories of age and hypertension. Conclusion: Current data suggest HSI and FLI are independently correlated with carotid atherosclerosis in T2DM. They may be a simple and useful marker for assessing the progression of diabetic macrovascular complications.

Morphological Carotid Plaque Area Is Associated With Glomerular Filtration Rate: A Study of South Asian Indian Patients With Diabetes and Chronic Kidney Disease

We evaluated the association between automatically measured carotid total plaque area (TPA) and the estimated glomerular filtration rate (eGFR), a biomarker of chronic kidney disease (CKD). Automated average carotid intima-media thickness (cIMTave) and TPA measurements in carotid ultrasound (CUS) were performed using AtheroEdge (AtheroPoint). Pearson correlation coefficient (CC) was then computed between the TPA and eGFR for (1) males versus females, (2) diabetic versus nondiabetic patients, and (3) between the left and right carotid artery. Overall, 339 South Asian Indian patients with either type 2 diabetes mellitus (T2DM) or CKD, or hypertension (stage 1 or stage 2) were retrospectively analyzed by acquiring cIMTave and TPA measurements of their left and right common carotid arteries (CCA; total CUS: 678, mean age: 54.2 ± 9.8 years; 75.2% males; 93.5% with T2DM). The CC between TPA and eGFR for different scenarios were (1) for males and females -0.25 (P < .001) and -0.35 (P < .001), respectively; (2) for T2DM and non-T2DM -0.26 (P < .001) and -0.49 (P = .02), respectively, and (3) for left and right CCA -0.25 (P < .001) and -0.23 (P < .001), respectively. Automated TPA is an equally reliable biomarker compared with cIMTave for patients with CKD (with or without T2DM) with subclinical atherosclerosis.

Global perspective on carotid intima-media thickness and plaque: should the current measurement guidelines be revisited?

Carotid intima-media thickness (cIMT) and carotid plaque (CP) currently act as risk predictors for CVD/Stroke risk assessment. Over 2000 articles have been published that cover either use cIMT/CP or alterations of cIMT/CP and additional image-based phenotypes to associate cIMT related markers with CVD/Stroke risk. These articles have shown variable results, which likely reflect a lack of standardization in the tools for measurement, risk stratification, and risk assessment. Guidelines for cIMT/CP measurement are influenced by major factors like the atherosclerosis disease itself, conventional risk factors, 10-year measurement tools, types of CVD/Stroke risk calculators, incomplete validation of measurement tools, and the fast pace of computer technology advancements. This review discusses the following major points: 1) the American Society of Echocardiography and Mannheim guidelines for cIMT/CP measurements; 2) forces that influence the guidelines; and 3) calculators for risk stratification and assessment under the influence of advanced intelligence methods. The review also presents the knowledge-based learning strategies such as machine and deep learning which may play a future role in CVD/stroke risk assessment. We conclude that both machine learning and non-machine learning strategies will flourish for current and 10-year CVD/Stroke risk prediction as long as they integrate image-based phenotypes with conventional risk factors.

Carotid Artery Imaging Is More Strongly Associated With the 10-Year Atherosclerotic Cardiovascular Disease Score Than Coronary Artery Imaging

PURPOSE

The aim of this study was to compare coronary and carotid artery imaging and determine which one shows the strongest association with atherosclerotic cardiovascular disease (ASCVD) score.

PATIENTS AND METHODS

Two separate series patients who underwent either coronary computed tomography angiography (CTA) or carotid CTA were included. We recorded the ASCVD scores and assessed the CTA imaging. Two thirds were used to build predictive models, and the remaining one third generated predicted ASCVD scores. The Bland-Altman analysis analyzed the concordance.

RESULTS

A total of 110 patients were included in each group. There was no significant difference between clinical characteristics. Three imaging variables were included in the carotid model. Two coronary models (presence of calcium or Agatston score) were created. The bias between true and predicted ASCVD scores was 0.37 ± 5.72% on the carotid model, and 2.07 ± 7.18% and 2.47 ± 7.82% on coronary artery models, respectively.

CONCLUSIONS

Both carotid and coronary artery imaging features can predict ASCVD score. The carotid artery was more associated to the ASCVD score than the coronary artery.

A Special Report on Changing Trends in Preventive Stroke/Cardiovascular Risk Assessment Via B-Mode Ultrasonography

PURPOSE OF REVIEW

Cardiovascular disease (CVD) and stroke risk assessment have been largely based on the success of traditional statistically derived risk calculators such as Pooled Cohort Risk Score or Framingham Risk Score. However, over the last decade, automated computational paradigms such as machine learning (ML) and deep learning (DL) techniques have penetrated into a variety of medical domains including CVD/stroke risk assessment. This review is mainly focused on the changing trends in CVD/stroke risk assessment and its stratification from statistical-based models to ML-based paradigms using non-invasive carotid ultrasonography.

RECENT FINDINGS

In this review, ML-based strategies are categorized into two types: non-image (or conventional ML-based) and image-based (or integrated ML-based). The success of conventional (non-image-based) ML-based algorithms lies in the different data-driven patterns or features which are used to train the ML systems. Typically these features are the patients' demographics, serum biomarkers, and multiple clinical parameters. The integrated (image-based) ML-based algorithms integrate the features derived from the ultrasound scans of the arterial walls (such as morphological measurements) with conventional risk factors in ML frameworks. Even though the review covers ML-based system designs for carotid and coronary ultrasonography, the main focus of the review is on CVD/stroke risk scores based on carotid ultrasound. There are two key conclusions from this review: (i) fusion of image-based features with conventional cardiovascular risk factors can lead to more accurate CVD/stroke risk stratification; (ii) the ability to handle multiple sources of information in big data framework using artificial intelligence-based paradigms (such as ML and DL) is likely to be the future in preventive CVD/stroke risk assessment.

Segment-specific association of carotid-intima-media thickness with cardiovascular risk factors - findings from the STAAB cohort study

Background

The guideline recommendation to not measure carotid intima-media thickness (CIMT) for cardiovascular risk prediction is based on the assessment of just one single carotid segment. We evaluated whether there is a segment-specific association between different measurement locations of CIMT and cardiovascular risk factors.

Methods

Subjects from the population-based STAAB cohort study comprising subjects aged 30 to 79 years of the general population from Würzburg, Germany, were investigated. CIMT was measured on the far wall of both sides in three different predefined locations: common carotid artery (CCA), bulb, and internal carotid artery (ICA). Diabetes, dyslipidemia, hypertension, smoking, and obesity were considered as risk factors. In multivariable logistic regression analysis, odds ratios of risk factors per location were estimated for the endpoint of individual age- and sex-adjusted 75th percentile of CIMT.

Results

2492 subjects were included in the analysis. Segment-specific CIMT was highest in the bulb, followed by CCA, and lowest in the ICA. Dyslipidemia, hypertension, and smoking were associated with CIMT, but not diabetes and obesity. We observed no relevant segment-specific association between the three different locations and risk factors, except for a possible interaction between smoking and ICA.

Conclusions

As no segment-specific association between cardiovascular risk factors and CIMT became evident, one simple measurement of one location may suffice to assess the cardiovascular risk of an individual.

In vitro-engineered non-antibody protein therapeutics

Antibodies have proved to be a valuable mode of therapy for numerous diseases, mainly owing to their high target binding affinity and specificity. Unfortunately, antibodies are also limited in several respects, chief amongst those being the extremely high cost of manufacture. Therefore, non-antibody binding proteins have long been sought after as alternative therapies. New binding protein scaffolds are constantly being designed or discovered with some already approved for human use by the FDA. This review focuses on protein scaffolds that are either already being used in humans or are currently being evaluated in clinical trials. Although not all are expected to be approved, the significant benefits ensure that these molecules will continue to be investigated and developed as therapeutic alternatives to antibodies. Based on the location of the amino acids that mediate ligand binding, we place all the protein scaffolds under clinical development into two general categories: scaffolds with ligand-binding residues located in exposed flexible loops, and those with the binding residues located in protein secondary structures, such as α-helices. Scaffolds that fall under the first category include adnectins, anticalins, avimers, Fynomers, Kunitz domains, and knottins, while those belonging to the second category include affibodies, β-hairpin mimetics, and designed ankyrin repeat proteins (DARPins). Most of these scaffolds are thermostable and can be easily produced in microorganisms or completely synthesized chemically. In addition, many of these scaffolds derive from human proteins and thus possess very low immunogenic potential. Additional advantages and limitations of these protein scaffolds as therapeutics compared to antibodies will be discussed.

Assessment of subclinical atherosclerosis in systemic lupus erythematosus: A systematic review and meta-analysis

OBJECTIVES

To determine whether subclinical atherosclerosis is increased in patients with systemic lupus erythematosus (SLE) compared to healthy individuals, using carotid intima-media thickness (CIMT), carotid plaque (CP) presence or flow-mediated dilatation (FMD).

METHODS

A systematic literature search was performed using MedLine, Embase and Cochrane databases. Two reviewers independently screened the articles to identify studies that compared the rates of atherosclerosis in SLE patients versus healthy controls. The results were pooled in a meta-analysis. Factors influencing the CIMT, CP or FMD results were collected.

RESULTS

Of the 203 articles initially identified, 68 were selected for the meta-analysis. Compared to healthy controls, SLE patients had a significantly increased CIMT (mean difference [MD] of 0.08mm, 95% CI [0.06-0.09], P<0.05), more CP (odds ratio 2.01, 95% CI [1.63-2.47], P<0.05) and decreased FMD (MD -3.96%, 95% CI [-5.37 to -2.54)], P<0.05). There was marked heterogeneity among the studies. However, the results of the meta-analysis that included only the CIMT per new international recommendations also showed an increased CIMT in SLE patients, but the heterogeneity was low (MD 0.04mm, 95% CI [0.02-0.06], P<0.05; I²=23%).

CONCLUSION

SLE patients exhibit increased subclinical atherosclerosis compared to healthy controls. CIMT is a promising measure for cardiovascular risk evaluations because non-invasive, non-radiation-based, reproducible. Thus, CIMT can be proposed as an alternative to the reliable CP evaluation and to FMD, which is influenced by independent factors such as smoking. Future studies should focus on reducing the heterogeneity of these measures using standardized procedures.

A Simple Disease-Guided Approach to Personalize ACC/AHA-Recommended Statin Allocation in Elderly People: The BioImage Study

BACKGROUND

The 2013 American College of Cardiology (ACC)/American Heart Association (AHA) guidelines recommend primary prevention with statins for individuals with ≥7.5% 10-year risk for atherosclerotic cardiovascular disease (ASCVD). Everyone living long enough will become eligible for risk-based statin therapy due to age alone.

OBJECTIVES

This study sought to personalize ACC/AHA risk-based statin eligibility using noninvasive assessment of subclinical atherosclerosis.

METHODS

In 5,805 BioImage participants without known ASCVD at baseline, those with ≥7.5% 10-year ASCVD risk were down-classified from statin eligible to ineligible if imaging revealed no coronary artery calcium (CAC) or carotid plaque burden (cPB). Intermediate-risk individuals were up-classified from optional to clear statin eligibility if CAC was ≥100 (or equivalent cPB).

RESULTS

At a median follow-up of 2.7 years, 91 patients had coronary heart disease and 138 had experienced a cardiovascular disease event. Mean age of the participants was 69 years, and 86% qualified for ACC/AHA risk-based statin therapy, with high sensitivity (96%) but low specificity (15%). CAC or cPB scores of 0 were common (32% and 23%, respectively) and were associated with low event rates. With CAC-guided reclassification, specificity for coronary heart disease events improved 22% (p < 0.0001) without any significant loss in sensitivity, yielding a binary net reclassification index (NRI) of 0.20 (p < 0.0001). With cPB-guided reclassification, specificity improved 16% (p < 0.0001) with a minor loss in sensitivity (7%), yielding an NRI of 0.09 (p = 0.001). For cardiovascular disease events, the NRI was 0.14 (CAC-guided) and 0.06 (cPB-guided). The positive NRIs were driven primarily by down-classifying the large subpopulation with CAC = 0 or cPB = 0.

CONCLUSIONS

Withholding statins in individuals without CAC or carotid plaque could spare a significant proportion of elderly people from taking a pill that would benefit only a few. This individualized disease-guided approach is simple and easy to implement in routine clinical practice.

Predictive Value of Arterial Stiffness and Subclinical Carotid Atherosclerosis for Cardiovascular Disease in Patients with Rheumatoid Arthritis

Objective.

We evaluated the predictive value of these vascular biomarkers for cardiovascular disease (CVD) events in patients with rheumatoid arthritis (RA): aortic pulse wave velocity (aPWV), augmentation index (AIx), carotid intima-media thickness (cIMT), and carotid plaques (CP). They are often used as risk markers for CVD.

Methods.

In 2007, 138 patients with RA underwent clinical examination, laboratory tests, blood pressure testing, and vascular biomarker measurements. Occurrence of CVD events was recorded in 2013. Predictive values were assessed in Kaplan-Meier plots, log-rank, and crude and adjusted Cox proportional hazard (PH) regression analyses.

Results.

Baseline median age and disease duration was 59.0 years and 17.0 years, respectively, and 76.1% were women. CVD events occurred in 10 patients (7.2%) during a mean followup of 5.4 years. Compared with patients with low aPWV, AIx, cIMT, and without CP, patients with high aPWV (p < 0.001), high AIx (p = 0.04), high cIMT (p = 0.01), and CP (p < 0.005) at baseline experienced more CVD events. In crude Cox PH regression analyses, aPWV (p < 0.001), cIMT (p < 0.001), age (p = 0.01), statin (p = 0.01), and corticosteroid use (p = 0.01) were predictive of CVD events, while AIx was nonsignificant (p = 0.19). The Cox PH regression estimates for vascular biomarkers were not significantly altered when adjusting individually for demographic variables, traditional CVD risk factors, RA disease-related variables, or medication. All patients who developed CVD had CP at baseline.

Conclusion.

CP, aPWV, and cIMT were predictive of CVD events in this cohort of patients with RA. Future studies are warranted to examine the additive value of arterial stiffness and carotid atherosclerosis markers in CVD risk algorithms. Regional Ethical Committee approval numbers 2009/1582 and 2009/1583.

The LIFE-Adult-Study: objectives and design of a population-based cohort study with 10,000 deeply phenotyped adults in Germany

Background

The LIFE-Adult-Study is a population-based cohort study, which has recently completed the baseline examination of 10,000 randomly selected participants from Leipzig, a major city with 550,000 inhabitants in the east of Germany. It is the first study of this kind and size in an urban population in the eastern part of Germany. The study is conducted by the Leipzig Research Centre for Civilization Diseases (LIFE). Our objective is to investigate prevalences, early onset markers, genetic predispositions, and the role of lifestyle factors of major civilization diseases, with primary focus on metabolic and vascular diseases, heart function, cognitive impairment, brain function, depression, sleep disorders and vigilance dysregulation, retinal and optic nerve degeneration, and allergies.

Methods/design

The study covers a main age range from 40-79 years with particular deep phenotyping in elderly participants above the age of 60. The baseline examination was conducted from August 2011 to November 2014. All participants underwent an extensive core assessment programme (5-6 h) including structured interviews, questionnaires, physical examinations, and biospecimen collection. Participants over 60 underwent two additional assessment programmes (3-4 h each) on two separate visits including deeper cognitive testing, brain magnetic resonance imaging, diagnostic interviews for depression, and electroencephalography.

Discussion

The participation rate was 33 %. The assessment programme was accepted well and completely passed by almost all participants. Biomarker analyses have already been performed in all participants. Genotype, transcriptome and metabolome analyses have been conducted in subgroups. The first follow-up examination will commence in 2016.