Composite carotid intima-media thickness as a risk predictor of coronary heart disease in a selected population in Sri Lanka

Background

Segment-specific variations of carotid intima-media thickness (CIMT) have not been assessed in South Asian populations. The purpose of this study was to determine if segment-specific CIMTs or a composite-CIMT score is a better risk predictor of coronary heart disease in South Asian populations.

Methods

A comparative prospective study was conducted from November 2019 to October 2020 in a hospital in Colombo, Sri Lanka. Based on pre-defined inclusion and exclusion criteria, cases (having a diagnosis of Coronary Heart Disease (CHD), n = 338) and controls (non-CHD group, n = 356) were recruited. Ultrasound examination of the common carotid (CCA), the carotid bulb (CB) and the internal carotid segments (ICA) of the carotid vessels was conducted by a radiologist, and CIMTs were measured. A composite-CIMT score defined as the average value of all six segments of the left and right sides was derived.

Results

694 participants were enrolled (male n = 399, 57.5%). The mean (±SD) age of the study sample was 60.2 (±9.86) years. There were variations in segment-specific values between the left and right vessels. The mean composite-CIMT value of the CHD group was significantly higher than that of the non-CHD group. A composite-CIMT score of 0.758 had a sensitivity of 98.4% and a specificity of 64.6% in distinguishing CHD from non-CHD groups (Area under the curve (AUC): 0.926).

Conclusions

Carotid artery segment-specific CIMT variations were present in this population. The composite CIMT score is better than segment-specific CIMTs in predicting CHD and may be used to predict CHD in this population.

Ankle pulse pressure to diastole ratio as a novel non-invasive costless screening tool for subclinical atherosclerosis

Atherosclerosis develops gradually as a subclinical condition and eventually becomes clinically apparent as heart disease or stroke. The degree of decreased arterial compliance affects both pulse pressure (PP) and diastolic blood pressure (DBP). These relations would be clear in the distal periphery. We propose that the ankle PP/ankle DBP ratio (APPD) can uncover the ongoing subclinical vascular risk. Based on the elastic chamber theory, APPD = (Cs-Cd)/(Cd-C0) in which Cs, Cd, and C0 represent arterial compliance at systolic pressure, diastolic pressure, and zero-pressure. For a given ventricular ejection, the value of Cs-Cd (i.e. PP) positively differs in the same person from brachium to ankle based on the distance from the heart, degree of arterial stiffness, and the local arterial function. On the other hand, the decreased arterial compliance increases the speed of reflected pulse waves to the heart resulting in earlier ventricular ejection by which the value of Cd-C0 (i.e. DBP) decreases over the arterial tree. In the same person, studies of ankle-brachial blood pressure (BP) differences revealed that PP greatly differed from brachium to ankle while DBPs were of minimal change or almost equivalent. However, DBP would be lower in those with arterial stiffness compared to others of the same age. Accordingly, APPD increases as arterial compliance decreases. Moreover, decreased APPD after a certain limit would reflect either local arterial stenosis or a compromised left ventricular function. When we divided ankle PP by ankle DBP, we could control the diversity of ankle PP as being not related to the BP level and possibly fluctuates in the same person. Additionally, APPD will indicate the extra rapid reflected pulse wave given in decreased DBP. Since increased common carotid artery intima-media thickness (CIMT) is a well-established marker of atherosclerosis, we initially studied 115 subjects apparently free form vascular diseases and had not taken a drug that can affect BP on the day of the study, aged 40-60 years, without a history of stroke, coronary heart disease or peripheral vascular disease to evaluate the relation between APPD and CIMT. The association was statistically significant even after adjusting for age, sex and important covariates and the area under the receiver operating characteristic curve was 0.902 ± 0.031. Therefore, the potential applicability of APPD as a tool for subclinical atherosclerosis was greatly proven.

Increased maximum common carotid intima-media thickness is associated with smoking and hypertension in Tochigi Prefecture residents

OBJECTIVE

We investigated maximum intima-media thickness of the common carotid artery (IMT-C_max) in residents of Tochigi Prefecture, who have been reported to have high stroke mortality.

METHOD

Our study included 840 individuals. All participants underwent carotid ultrasonography and answered a questionnaire during participation in a health festival in Tochigi Prefecture. The questionnaire was designed to collect information on age, gender, and risk factors for stroke. IMT-C_max was measured. Statistical analyses were performed to identify factors contributing to IMT-C_max values ≥1.1 mm.

RESULTS

In total, 117 subjects had an IMT-C_max value ≥1.1 mm. IMT-C_max correlated significantly with age, current smoking, hypertension, diabetes mellitus, heart disease, and previous symptomatic stroke (p < 0.05) in univariate analysis. Current smoking (p < 0.001, odds ratio 3.88) and hypertension (p = 0.0070, odds ratio 1.83) were seen as significant contributing factors to IMT-C_max ≥1.1 mm in logistic regression analysis adjusted by age, gender, and previous symptomatic stroke.

CONCLUSION

We identified current smoking and hypertension as the most significant contributing factors to increased IMT-C_max in residents of Tochigi Prefecture, emphasizing the importance of routine blood pressure monitoring and anti-smoking education in this population.

Prevention of Carotid Artery Atherosclerosis: What is the Evidence?

Carotid artery atherosclerosis (CAA) represents a significant form of atherosclerosis with stroke as a major consequence. Whether it is a unique form of atherosclerosis is not established. However, this is not of major clinical relevance as no specific preventive measures over and above the established ones for cardiovascular risk are well established. Major risk factors for CAA are elevated low-density lipoprotein cholesterol (LDL-C), diabetes mellitus, tobacco use, hypertension, and increased inflammation. Identification of CAA prior to a clinical event centers on imaging studies. Studies with magnetic resonance imaging result in the best definition of CAA plaque morphology. Medical measures that result in prevention are especially centered on statins (marked reduction of the LDL-C) and hypertension control. Nonprocedural therapeutic measures to avoid and delay complications involve antiplatelet medications. Benefits from other measures such as increasing high-density lipoprotein cholesterol and increased exercise appear desirable but require more clinical evidence. In conclusion, there are enough evidence-based medicine results to demand intensive medical preventive measures and not just relegate the patient with asymptomatic or symptomatic CAA to decision-making only involving the surgeon and interventionalist.

Biological Antioxidant Potential Negatively Correlates With Carotid Artery Intima-Media Thickness

Oxidative stress is a crucial factor in the pathogenesis and development of cardiovascular disease. Recently, simplified methods for the detection of reactive oxygen species (ROS) using the derivatives of reactive oxygen metabolites (d-ROMs) test as an index of ROS products and the biological antioxidant potential (BAP) test as an index of antioxidant potential have been utilized. These methods are easy to perform, quick, inexpensive since they use small equipment, and provide reliable results compared with established oxidative stress and antioxidant markers. Because oxidative stress has been shown to represent the balance of production of ROS and antioxidant capacity, it is more appropriate to evaluate ROS and antioxidant capacity simultaneously. However, no study has examined the associations among d-ROMs, BAP values, and carotid artery intima-media thickness (IMT) concurrently. Therefore, we studied the associations among d-ROMs, BAP values, and the carotid artery IMT. Carotid artery IMT, blood pressure (BP), fasting circulating d-ROMs, BAP, glucose metabolism, lipid, and C-reactive protein levels were measured in 95 subjects (age: 49.5 ± 13.8 years; men: 41; women: 54), including 42 healthy subjects and 53 patients with hypertension, dyslipidemia, and diabetes mellitus who were not on medication. The results of multiple regression analysis revealed that dependent carotid artery IMT determinants remained significantly associated with age, systolic BP, total cholesterol, and BAP, whereas dependent BAP determinants remained significantly associated with body mass index and carotid artery IMT. BAP was strongly correlated with carotid artery IMT in our cohort. Our results suggest that BAP may be a useful risk marker for carotid atherosclerosis.

Causes of changes in carotid intima-media thickness: a literature review

Atherosclerosis causes significant morbidity and mortality. Carotid intima-media thickness (CIMT) predicts future cardiovascular and ischaemic stroke incidence. CIMT, a measure of atherosclerotic disease, can be reliably determined in vivo by carotid ultrasound. In this review, we determined that CIMT is associated with traditional cardiovascular risk factors such as age, sex, race, smoking, alcohol consumption, habitual endurance exercise, blood pressure, dyslipidemia, dietary patterns, risk-lowering drug therapy, glycemia, hyperuricemia, obesity-related anthropometric parameters, obesity and obesity-related diseases. We also found that CIMT is associated with novel risk factors, including heredity, certain genotypic indices, anthropometric cardiovascular parameters, rheumatoid arthritis, immunological diseases, inflammatory cytokines, lipid peroxidation, anthropometric hemocyte parameters, infectious diseases, vitamin D, matrix metalloproteinases, and other novel factors and diseases. However, the conclusions are inconsonant; the underlying causes of these associations remain to be further explored.

Coronary Plaque Burden at Coronary CT Angiography in Asymptomatic Men and Women

Purpose To assess the relationship between total, calcified, and noncalcified coronary plaque burdens throughout the entire coronary vasculature at coronary computed tomographic (CT) angiography in relationship to cardiovascular risk factors in asymptomatic individuals with low-to-moderate risk. Materials and Methods This HIPAA-compliant study had institutional review board approval, and written informed consent was obtained. Two hundred two subjects were recruited to an ongoing prospective study designed to evaluate the effect of HMG-CoA reductase inhibitors on atherosclerosis. Eligible subjects were asymptomatic individuals older than 55 years who were eligible for statin therapy. Coronary CT angiography was performed by using a 320-detector row scanner. Coronary wall thickness and plaque were evaluated in all epicardial coronary arteries greater than 2 mm in diameter. Images were analyzed by using dedicated software involving an adaptive lumen attenuation algorithm. Total plaque index (calcified plus noncalcified plaque) was defined as plaque volume divided by vessel length. Multivariable regression analysis was performed to determine the relationship between risk factors and plaque indexes. Results The mean age of the subjects was 65.5 years ± 6.9 (standard deviation) (36% women), and the median coronary artery calcium (CAC) score was 73 (interquartile range, 1-434). The total coronary plaque index was higher in men than in women (42.06 mm(2) ± 9.22 vs 34.33 mm(2) ± 8.35; P < .001). In multivariable analysis controlling for all risk factors, total plaque index remained higher in men than in women (by 5.01 mm(2); P = .03) and in those with higher simvastatin doses (by 0.44 mm(2)/10 mg simvastatin dose equivalent; P = .02). Noncalcified plaque index was positively correlated with systolic blood pressure (β = 0.80 mm(2)/10 mm Hg; P = .03), diabetes (β = 4.47 mm(2); P = .03), and low-density lipoprotein (LDL) cholesterol level (β = 0.04 mm(2)/mg/dL; P = .02); the association with LDL cholesterol level remained significant (P = .02) after additional adjustment for the CAC score. Conclusion LDL cholesterol level, systolic blood pressure, and diabetes were associated with noncalcified plaque burden at coronary CT angiography in asymptomatic individuals with low-to-moderate risk. (©) RSNA, 2015 Online supplemental material is available for this article.

Phase II anti-inflammatory and immune-modulating drugs for acute ischaemic stroke

INTRODUCTION

Stroke is the second leading cause of death worldwide and the leading cause of adult neurological disability. Despite advances in stroke unit care, and increasing use of thrombolysis, there remains an urgent need for safe and effective treatments for acute ischaemic stroke. However, this is against a backdrop of multiple failures in translational drug development. Cerebral ischaemia initiates a complex cascade of immune and inflammatory pathways in the brain microvasculature and periphery, which contribute to the evolution of cerebral injury, resolution and repair. Targeting specific inflammatory or immune pathways, therefore, represents an attractive treatment strategy in acute ischaemic stroke. Although anti-inflammatory drugs have already failed in clinical trial development, several are currently at the Phase II developmental stage.

AREAS COVERED

The authors highlight several candidate drugs, which modulate a range of inflammatory and immune pathways, and have been investigated in pre-clinical and Phase II studies to date.

EXPERT OPINION

Drugs targeting inflammatory and immune pathways offer theoretical advantages including potentially longer therapeutic time windows and effects complementary to thrombolysis (ameliorating reperfusion injury). Fundamental changes in the approach to pre-clinical and clinical drug development are required to facilitate successful translation of promising candidate drugs into clinical practice.

Lipid-lowering efficacy of rosuvastatin

BACKGROUND

Rosuvastatin is one of the most potent statins and is currently widely prescribed. It is therefore important to know the dose-related magnitude of effect of rosuvastatin on blood lipids.

OBJECTIVES

Primary objective To quantify the effects of various doses of rosuvastatin on serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, non-HDL-cholesterol and triglycerides in participants with and without evidence of cardiovascular disease. Secondary objectives To quantify the variability of the effect of various doses of rosuvastatin.To quantify withdrawals due to adverse effects (WDAEs) in the randomized placebo-controlled trials.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) Issue 10 of 12, 2014 in The Cochrane Library, MEDLINE (1946 to October week 5 2014), EMBASE (1980 to 2014 week 44), Web of Science Core Collection (1970 to 5 November 2014) and BIOSIS Citation Index (1969 to 31 October 2014). No language restrictions were applied.

SELECTION CRITERIA

Randomized controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of rosuvastatin on blood lipids over a duration of three to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included and extracted data. WDAEs information was collected from the placebo-controlled trials.

MAIN RESULTS

One-hundred and eight trials (18 placebo-controlled and 90 before-and-after) evaluated the dose-related efficacy of rosuvastatin in 19,596 participants. Rosuvastatin 10 to 40 mg/day caused LDL-cholesterol decreases of 46% to 55%, when all the trials were combined using the generic inverse variance method. The quality of evidence for these effects is high. Log dose-response data over doses of 1 to 80 mg, revealed strong linear dose-related effects on blood total cholesterol, LDL-cholesterol and non-HDL-cholesterol. When compared to atorvastatin, rosuvastatin was about three-fold more potent at reducing LDL-cholesterol. There was no dose-related effect of rosuvastatin on blood HDL-cholesterol, but overall, rosuvastatin increased HDL by 7%. There is a high risk of bias for the trials in this review, which would affect WDAEs, but unlikely to affect the lipid measurements. WDAEs were not statistically different between rosuvastatin and placebo in 10 of 18 of these short-term trials (risk ratio 0.84; 95% confidence interval 0.48 to 1.47).

AUTHORS' CONCLUSIONS

The total blood total cholesterol, LDL-cholesterol and non-HDL-cholesterol-lowering effect of rosuvastatin was linearly dependent on dose. Rosuvastatin log dose-response data were linear over the commonly prescribed dose range. Based on an informal comparison with atorvastatin, this represents a three-fold greater potency. This review did not provide a good estimate of the incidence of harms associated with rosuvastatin because of the short duration of the trials and the lack of reporting of adverse effects in 44% of the placebo-controlled trials.

Change of carotid intima-media thickness is associated with age in elderly Japanese patients without a history of cardiovascular disease

AIM

The present study aimed to evaluate the relationship between the change of carotid intima-media thickness (CIMT) and clinical characteristics in Japanese patients without a history of cardiovascular disease.

METHODS

The study participants were 149 Japanese patients without a history of cardiovascular disease treated in our outpatient department. The in all participants CIMT was measured with ultrasonography at baseline and after a mean interval of 2.4 years. Study participants were divided into a middle-aged group (younger than 65 years: n = 59) and an elderly group (65 years or older: n = 90). The annual CIMT change (ΔCIMT) was calculated, and the associations between ΔCIMT and clinical characteristics, including age, were evaluated in both groups.

RESULTS

The ΔCIMT was significantly correlated with age in all participants (r = 0.222; P < 0.05) and in elderly participants (r = 0.234; P < 0.05), but was not correlated with other risk factors. The annual ΔCIMT was significantly higher in elderly participants (0.015 ± 0.096 mm) than in middle-aged participants (-0.018 ± 0.088 mm; P < 0.05). Multivariate linear regression analysis with ΔCIMT as a dependent variable and risk factors as independent variables showed that ΔCIMT was significantly associated with age in all participants (β = 0.002; P < 0.05) and in elderly participants (β = 0.004; P < 0.05), but not with other risk factors.

CONCLUSIONS

Annual CIMT change is associated with age, rather than with other clinical characteristics, including traditional cardiovascular risk factors, such as diabetes and hypertension, in elderly Japanese patients without a history of cardiovascular disease.