Validation of a Carotid Intima-Media Thickness Border Detection Program for Use in an Office Setting

Early indicators of cardiovascular disease are evident in children and adolescents with cerebral palsy

BACKGROUND

Cardiovascular disease (CVD) is a leading cause of early mortality among young adults with cerebral palsy. While low physical activity in childhood has been hypothesized as a potential contributor to increased CVD risk in early adulthood, little is known about timing of vascular disease progression and the presence of subclinical atherosclerosis has not been extensively evaluated in children with cerebral palsy.

OBJECTIVE

The aim of this study was to determine if measures of vascular structure and function are different between children and adolescents with and without cerebral palsy.

METHODS

In this cross-sectional study, we measured carotid intima-media thickness (CIMT), and brachial artery flow-mediated dilation (FMD) of children with and without cerebral palsy. Group means for CIMT and brachial artery FMD absolute (FMDA) and percent of relative change (FMDR%) were compared using Wilcoxon rank-sum tests.

RESULTS

A total of 26 children and adolescents with cerebral palsy (46.1% girls, mean age = 15.0 ± 2.0 years) and 19 controls (68.4% girls, mean age = 13.3 ± 2.6 years) participated. Children with cerebral palsy had significantly greater average CIMT (0.43 ± 0.02 mm) than children without cerebral palsy (0.41 ± 0.01 mm, p = 0.04), and lower FMDA (0.16 ± 0.15 mm vs. 0.29 ± 0.20 mm; respectively, p = 0.03).

CONCLUSIONS

Children and adolescents with cerebral palsy may exhibit impairments in vascular structure and function which represent an increased risk of premature atherosclerosis compared to children without cerebral palsy. Additional research to identify risk factors specific to children with cerebral palsy that would support the development of effective screening processes for early identification would enable clinicians to implement targeted preventive strategies.

Diagnostic accuracy of carotid intima media thickness by B-mode ultrasonography in coronary artery disease patients

Introduction

Cardiovascular diseases (CVD) are the main cause of premature deaths worldwide, and atherosclerosis (AS) is a major risk factor associated with them. B-mode ultrasound is a well-validated research tool that has been translated increasingly into clinical practice. The aim of the study was to assess the diagnostic accuracy of carotid intima media thickness by B-mode ultrasonography in coronary artery disease patients.

Material and methods

This was a case control study, including 100 cases and the same number of controls. Patients with positive angiographic findings and chest pain were considered as cases and those without as negative. Duplex carotid ultrasound was used to detect intima-media thickness (IMT). B-mode real-time ultrasonic images were obtained with a 7 MHz transducer. An intima media thickness of 0.6 mm was considered as being without plaque.

Results

The angiographic findings were single-vessel disease, double-vessel disease, and triple-vessel disease in 18%, 11.5%, and 20.5% of cases, respectively, while there were no findings in controls. There was plaque formation in 14.5% and calcification in 12% of the cases. Sensitivity of B-mode ultrasonography was found to be 78%, specificity 75%, positive predictive value 75.72%, and negative predictive value 77.31%.

Conclusions

Carotid ultrasonography can be utilised as a valuable screening tool due to having several advantages, including ease of application, reproducibility, low cost, and strong correlation with atherosclerosis.

Clinical utility of carotid ultrasonography: Application for the management of patients with diabetes

Carotid ultrasonography is a non-invasive, simple and inexpensive modality to assess the severity of atherosclerosis. This article reviews related articles, summarizes the rationale for the application of carotid ultrasonography in clinical practice, and addresses the features and the limitations of carotid ultrasonography in cardiovascular risk prediction. Numerous large studies have confirmed that various carotid ultrasound measures, such as carotid intima-media thickness, the presence or absence of carotid plaque, plaque number and plaque area, can be independent predictors of cardiovascular diseases in individuals with and without diabetes mellitus. Furthermore, many studies showed that the use of carotid intima-media thickness (especially maximum intima-media thickness, including plaque thickness) and/or carotid plaque in addition to traditional risk factors significantly improved the prediction of the occurrence of cardiovascular diseases, while controversy remains. Several studies showed that the progression of carotid intima-media thickness also can be a surrogate end-point of cardiovascular events. However, the accumulated evidence has not been sufficient. Further study with sufficient power should be carried out. As plaque disruption, which plays a crucial role in the pathogenesis of cardiovascular events, is dependent on the content of lipid in the atheroma and the thickness of the fibrous cap, tissue characterization of a plaque might be useful for determining its fragility. Interestingly, recent studies have shown that ultrasonic tissue characterization of carotid lesions could improve the prediction ability of future cardiovascular diseases. Thus, carotid ultrasonography is a useful modality for better clinical practice of atherosclerosis in patients with diabetes.

The REVAMP trial to evaluate HIV resistance testing in sub-Saharan Africa: a case study in clinical trial design in resource limited settings to optimize effectiveness and cost effectiveness estimates

BACKGROUND

In sub-Saharan Africa, rates of sustained HIV virologic suppression remain below international goals. HIV resistance testing, while common in resource-rich settings, has not gained traction due to concerns about cost and sustainability.

OBJECTIVE

We designed a randomized clinical trial to determine the feasibility, effectiveness, and cost-effectiveness of routine HIV resistance testing in sub-Saharan Africa.

APPROACH

We describe challenges common to intervention studies in resource-limited settings, and strategies used to address them, including: (1) optimizing generalizability and cost-effectiveness estimates to promote transition from study results to policy; (2) minimizing bias due to patient attrition; and (3) addressing ethical issues related to enrollment of pregnant women.

METHODS

The study randomizes people in Uganda and South Africa with virologic failure on first-line therapy to standard of care virologic monitoring or immediate resistance testing. To strengthen external validity, study procedures are conducted within publicly supported laboratory and clinical facilities using local staff. To optimize cost estimates, we collect primary data on quality of life and medical resource utilization. To minimize losses from observation, we collect locally relevant contact information, including Whatsapp account details, for field-based tracking of missing participants. Finally, pregnant women are followed with an adapted protocol which includes an increased visit frequency to minimize risk to them and their fetuses.

CONCLUSIONS

REVAMP is a pragammatic randomized clinical trial designed to test the effectiveness and cost-effectiveness of HIV resistance testing versus standard of care in sub-Saharan Africa. We anticipate the results will directly inform HIV policy in sub-Saharan Africa to optimize care for HIV-infected patients.

Bone Mineral Density Is Positively Related to Carotid Intima-Media Thickness: Findings From a Population-Based Study in Adolescents and Premenopausal Women

Osteoporosis and cardiovascular disease (CVD) are both common causes of morbidity and mortality. Previous studies, mainly of people older than 60 years, suggest a relationship between these conditions. Our aim was to determine the association between bone characteristics and CVD markers in younger and middle-aged individuals. Women (n = 3366) and their adolescent offspring (n = 4368) from the UK population-based cohort study, Avon Longitudinal Study of Parents and Children (ALSPAC), were investigated. We measured total body (TB) and hip bone mineral density (BMD), TB bone area (BA) and bone mineral content (BMC) by dual-energy X-ray absorptiometry (DXA), and carotid intima-media thickness (cIMT) by high-resolution ultrasound. Arterial distensibility was calculated as the difference between systolic and diastolic arterial diameters. Linear regression determined associations between bone exposures and cIMT (in adolescents) and both cIMT and arterial distensibility (in women), generating partial correlation coefficients. Mean (SD) age of women was 48 (4.2) years, body mass index (BMI) was 26.2 (5.0) kg/m² , and 71% were premenopausal. In confounder-adjusted analyses (age, height, lean mass, fat mass, menopause, smoking, estrogen replacement, calcium/vitamin D supplementation, and education) TB and hip BMD were both positively associated with cIMT (0.071 [0.030, 0.112], p = 0.001; 0.063 [0.025, 0.101], p = 0.001, respectively). Femoral neck BMD and TB BMD, BMC, and BA were positively associated with arterial distensibility. Mean (SD) age of adolescents was 17 (0.4) years, BMI was 23 (4.1) kg/m² , and 44.5% were male. Total hip and TB measurements were positively associated with cIMT, with similar magnitudes of association to those found in their mothers. In contrast to most published findings, we identified weak positive associations between BMD and cIMT in predominantly premenopausal women and their adolescent offspring. We found greater femoral neck BMD and TB DXA measurements to be associated with reduced arterial stiffness. Rather than a relationship with preclinical atherosclerosis, in these relatively young populations, we speculate our associations between BMD, cIMT, and arterial distensibility may reflect a shared relationship between bone and vascular growth and development. © 2016 American Society for Bone and Mineral Research.

The Framingham Score and the Systematic Coronary Risk Evaluation at Low Cutoff Values Are Useful Surrogate Markers of High-risk Subclinical Atherosclerosis in Patients with Rheumatoid Arthritis

Objective.

We determined the performance of the Framingham score and the Systematic COronary Risk Evaluation (SCORE) in assessing high-risk atherosclerosis in patients with rheumatoid arthritis (RA).

Methods.

We assembled 330 cases without established cardiovascular disease (CVD), diabetes, and moderate or severe chronic kidney disease among 451 consecutive Spanish patients who underwent CVD risk screening and carotid ultrasound-determined plaque assessment. The findings were validated in 90 black and 97 white African patients.

Results.

When sensitivity for the Framingham score was set at 80% in receiver-operator curve analysis [area under the curve (AUC) = 0.799], the corresponding cutoff value and specificity were 7.3% and 63%, respectively. At a specificity of 80%, the cutoff value and sensitivity were 10.8% and 65%, respectively. When sensitivity for SCORE (AUC = 0.747) was set at 80%, the cutoff value and specificity were 0.5% and 58%, respectively. At a specificity of 80%, the cutoff value and sensitivity were 1.5% and 50%, respectively. Upon applying a cutoff value of 7.3% for the Framingham and 0.5% for SCORE in African white patients with RA, the corresponding sensitivities and specificities were 67% and 72%, and 67% and 55%, respectively. CVD risk equations did not discriminate between black African patients with and without plaque (AUC = 0.544 and 0.549 for Framingham score and SCORE, respectively).

Conclusion.

The Framingham score and SCORE at markedly low cutoff values of 7.3% to 10.8% and 0.5% to 1.5%, respectively, can usefully estimate plaque presence in RA. Effective population-specific CVD risk assessment strategies are needed in black African patients with RA.

Assessment and relevance of carotid intima-media thickness (C-IMT) in primary and secondary cardiovascular prevention

Interventions aimed to prevent cardiovascular diseases (CVD) are more effective if administered to subjects carefully selected according to their CVD risk. Usually, this risk is evaluated on the basis of the presence and severity of conventional vascular risk factors (VRFs); however, atherosclerosis, the main pathologic substrate of CVD, is not directly revealed by VRFs. The measurement of the arterial wall, using imaging techniques, has increased the early identification of individuals prone to develop atherosclerosis and to quantify its changes over time.

B-mode ultrasound is a technique which allows a non-invasive assessment of the arterial wall of peripheral arteries (e.g. extracranial carotid arteries), and provides measures of the intima-media thickness complex (C-IMT) and additional data on the occurrence, localization and morphology of plaques.

Being an independent predictor of vascular events, C-IMT has been considered as a tool to optimize the estimation of CVD risk but this application is still a matter of debate. Though the technique is innocuous, relatively inexpensive and repeatable, its use in the clinical practice is limited by the lack of standardized protocols and clear guidelines.

This review outlines the rationale for the potential use of C-IMT in the stratification of cardio- and cerebro-vascular risk and discusses several topics related to the measurement of this variable, which are still controversial among experts of the field.

Kidney function, endothelial activation and atherosclerosis in black and white Africans with rheumatoid arthritis

Objective

To determine whether kidney function independently relates to endothelial activation and ultrasound determined carotid atherosclerosis in black and white Africans with rheumatoid arthritis (RA).

Methods

We calculated the Jelliffe, 5 Cockcroft-Gault equations, Salazar-Corcoran, Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) estimated glomerular filtration rate (EGFR) equations in 233 (112 black) RA patients.

Results

The CKD-EPI eGFR was <90 ml/min/1.73m² in 49.1% and 30.6% of black and white patients, respectively (odds ratio (95% confidence interval) = 2.19 (1.28–3.75), p = 0.004). EGFRs were overall consistently associated with monocyte chemoattractant protein-1 and angiopoietin 2 concentrations in white patients, and with carotid intima-media thickness and plaque in black participants. Amongst black patients, plaque prevalence was 36.7% and the area under the curve (AUC) of the receiver operating characteristic (ROC) curve was not associated with plaque presence for the MDRD equation (p = 0.3), whereas the respective relationship was significant or borderline significant (p = 0.003 to 0.08) and of similar extent (p>0.1 for comparisons of AUC (SE)) for the other 8 equations. Based on optimal eGFR cutoff values with sensitivities and specificities ranging from 42 to 60% and 70 to 91% respectively, as determined in ROC curve analysis, a low eGFR increased the odds ratio for plaque 2.2 to 4.0 fold.

Conclusion

Reduced kidney function is independently associated with atherosclerosis and endothelial activation in black and white Africans with RA, respectively. CKD is highly prevalent in black Africans with RA. Apart from the MDRD, eGFR equations are useful in predicting carotid plaque presence, a coronary heart disease equivalent, amongst black African RA patients.

Can common carotid intima media thickness serve as an indicator of both cardiovascular phenotype and risk among black Africans?

BACKGROUND

It is not known whether common carotid intima media thickness (CIMT) can serve as a surrogate marker of cardiovascular risk among black Africans. Therefore, we examined whether CIMT differed significantly among individuals with distinct cardiovascular phenotype and correlated significantly with traditional cardiovascular risk factors in a black African population.

METHODS

CIMT was measured in 456 subjects with three distinct cardiovascular phenotypes - 175 consecutive Nigerian African stroke patients, 161 hypertensive patients without stroke and 120 normotensive non-smoking adults. For each pair of cardiovascular phenotypes, c-statistics were obtained for CIMT and traditional vascular risk factors (including age, gender, weight, waist circumference, smoking, alcohol, systolic and diastolic blood pressures, fasting plasma glucose, fasting total cholesterol). Pearson's correlation coefficients were calculated to quantify bivariate relationships.

FINDINGS

Bilaterally, CIMT was significantly different among the three cardiovascular phenotypes (right: p < 0.001, F = 33.8; left: p < 0.001, F = 48.6). CIMT had a higher c-statistic for differentiating stroke versus normotension (c = 0.78 right; 0.82 left, p < 0.001) and hypertension versus normotension (c = 0.65 right; 0.71 left, p < 0.001) than several traditional vascular risk factors. Bilaterally, combining all subjects, CIMT was the only factor that correlated significantly (right: 0.12 ≤ r ≤ 0.41, 0.018 ≤ p < 0.0001; left: 0.18 ≤ r ≤ 0.41, 0.005 ≤ p < 0.0001) to all the traditional cardiovascular risk factors assessed.

CONCLUSION

Our findings support CIMT as a significant indicator of both cardiovascular risk and phenotype among adult black Africans. However, specific thresholds need to be defined based on prospective studies.

Circulating concentrations of the novel adipokine chemerin are associated with cardiovascular disease risk in rheumatoid arthritis

OBJECTIVE

Depending on physiological context, the adipokine chemerin can reduce or enhance cardiovascular risk. We investigated whether chemerin concentrations represent cardiovascular disease risk in rheumatoid arthritis (RA).

METHODS

We assessed ELISA-determined chemerin concentrations and those of 4 early endothelial activation molecules as well as angiopoietin 2, which mediates angiogenesis and thereby contributes to advanced atherosclerosis, the common carotid artery intima-media thickness (cIMT), and carotid artery plaque by ultrasound in 236 patients (114 black and 122 white) with RA. Relationships were identified in potential confounder and mediator-adjusted mixed regression models.

RESULTS

Mean (SD) chemerin and median (interquartile range) angiopoietin 2 concentrations were 114 (35) ng/ml and 2560 (2044-3341) pg/ml, respectively; the mean (SD) cIMT was 0.708 (0.110) mm, and 40.3% of patients had plaque. Chemerin concentrations were not related to those of early endothelial activation molecules, but associated with those of angiopoietin 2 [β SE = 0.002 (0.0004), p < 0.0001] and plaque [OR 1.006 (95% CI 1.00-1.013), p = 0.05] in all patients. The presence of major conventional cardiovascular risk factors, generalized and abdominal obesity, and RA severity markers modified the independent chemerin-cardiovascular risk relations (interaction p < 0.05). Consequently, chemerin concentrations were associated with cIMT in those with but not without overweight or generalized obesity and abdominal obesity [β SE = 0.001 (0.0003), p = 0.005 and 0.001 (0.0001), p = 0.001 vs -0.001 (0.0004), p = 0.2 and -0.0002 (0.0004), p = 0.6, respectively], and with plaque in those without but not with generalized obesity [OR 1.008 (95% CI) 1.000-1.016, p = 0.03 vs 1.003 (0.990-1.017), p = 0.6, respectively]. The β (SE) for the chemerin-intima-media thickness relations in patients with overweight or generalized obesity and abdominal obesity were larger than in those without these characteristics (p < 0.0001 and = 0.04, respectively).

CONCLUSION

Chemerin is associated with endothelial activation and atherosclerosis in RA. Adiposity influences the chemerin-atherosclerotic phenotype relations in RA.

Adiponectin and atherosclerosis in rheumatoid arthritis

In the present study, we examined the potential impact of adiponectin on carotid ultrasound determined atherosclerosis in 210 (119 black and 91 white) RA patients in mixed regression models. Total adiponectin concentrations were smaller in patients with compared to those without the metabolic syndrome (MetS) defined waist criterion (median (range) = 6.47 (1.23–34.54) versus 8.38 (0.82–85.30) ng/mL, P = 0.02, resp.); both total and high molecular weight (HMW) adiponectin concentrations were larger in patients with compared to those without joint deformities (7.97 (0.82–85.30) and 3.51 (0.01–35.40) versus 5.36 (1.29–19.49) and 2.34 (0.01–19.49) ng/mL, P = 0.003 and 0.02, resp.). Total and HMW adiponectin concentrations were associated with carotid artery plaque in patients with MetS waist (odds ratio (95% CI) = 0.87 (0.76–0.99) and 0.92 (0.85–0.99) per 1-standard deviation increment, P = 0.02 for both) and those without joint deformities (odds ratio (95% CI) = 0.94 (0.88–0.99) and 0.94 (0.89–0.99), P = 0.03 for both). Plaque prevalence was lower in patients without compared to those with joint deformities (23.4% versus 42.6, P = 0.004 in multivariable analysis). In RA patients with abdominal obesity or no clinically evident joint damage, adiponectin concentrations are reduced but nevertheless associated with decreased carotid atherosclerosis.

Retinol binding protein 4 concentrations relate to enhanced atherosclerosis in obese patients with rheumatoid arthritis

Background

Retinol binding protein 4 (RBP) enhances metabolic risk and atherogenesis. Whether RBP4 contributes to cardiovascular risk in rheumatoid arthritis (RA) is unknown.

Methods

We assessed RBP4 concentrations and those of endothelial activation molecules including E-selectin, vascular cell adhesion molecule-1, intercellular adhesion molecule-1 and monocyte chemoattractant protein-1 by ELISA, and the common carotid artery intima-media thickness (cIMT) and carotid artery plaque by ultrasound in 217 (112 black and 105 white) patients with RA. Relationships were identified in potential confounder and mediator adjusted mixed regression models.

Results

RBP4 concentrations were associated with systolic and mean blood pressure, and those of glucose and E-selectin (partial R = −0.207 (p = 0.003), −0.195 (p = 0.006), −0.155 (p = 0.03) and −0.191 (p = 0.007), respectively in all patients); these RBP4-cardiovascular risk relations were mostly reproduced in patients with but not without adverse traditional or non-traditional cardiovascular risk profiles. RBP4 concentrations were not associated with atherosclerosis in all patients, but related independently to cIMT (partial R = 0.297, p = 0.03) and plaque (OR (95%CI) = 2.95 (1.31–6.68), p = 0.008) in those with generalized obesity, as well as with plaque in those with abdominal obesity (OR (95%CI) = 1.95 (1.12–3.42), p = 0.01).

Conclusion

In the present study, RBP4 concentrations were inversely associated with metabolic risk and endothelial activation in RA. This requires further investigation. RBP4 concentrations were related to enhanced atherosclerosis in patients with generalized or/and abdominal obesity.

Carotid intima-media thickness: Current evidence, practices, and Indian experience

As the developed and developing nations cope up with increasing predisposition to cardiovascular diseases (CVD) by adopting lifestyle changes the burden of coronary artery disease continues to rise globally. The presence of modifiable risk factors, which account for more than 90% of the cardiovascular (CV) risk, cannot always be interpreted as the presence of atherosclerotic heart disease and absence of modifiable risk factors do not guarantee absence of atherosclerotic changes in the arterial tree. Increasing awareness about primordial prevention and primary prevention of CVD is of vital importance in such scenarios. Ultrasonographic measurement of intima media thickness has been reported as a procedure to detect the early stages of atherosclerosis. Carotid intima media thickness (CIMT) testing is a safe, noninvasive and cost effective method to detect early atherosclerotic vascular diseases. This method of CV risk evaluation drew attention worldwide and of Indian physicians because of its feasibility in Indian population. Hence, detection and management of atherosclerosis in asymptomatic individuals will go a long way in preventing atherosclerotic diseases and prolonging survival and improving quality of life.

Carotid ultrasound examination as an aging and disability marker

AIM

To explore the usefulness of carotid ultrasound examination as a marker of aging and predictor of disability among older people.

METHODS

Carotid ultrasound, measuring carotid intima media thickness (CIMT) and recording the presence of plaques, was carried out in 152 adults aged 29-59 years (47 women) and in 107 older adults aged 61-88 years (86 women). In all, clinical routine laboratory parameters and lymphocyte telomere length as T/S ratio were measured. Among older adults, 12-min walk, timed up and go, hand grip and quadriceps strength were determined.

RESULTS

CIMT was significantly higher among older people and T/S ratio was significantly higher in young women. Carotid plaques were found in one adult and 17 older people. A multiple regression analysis accepted age, systolic blood pressure and T/S ratios as independent predictors of CIMT (R(2) = 0.51). Among older people, a logistic regression accepted age and the presence of carotid plaques as significant predictors of a 12-min walk speed below 1 m/s.

CONCLUSIONS

An abnormal 12-min walk as an indicator of functional decline among older people is associated with the presence of carotid artery plaques. CIMT is independently associated with age.

Carotid intima-media thickness testing as an asymptomatic cardiovascular disease identifier and method for making therapeutic decisions

Cardiovascular disease (CVD) is the leading cause of death and disability in the United States. Although current therapies can reduce the risk for CVD, they are only given to patients who are considered to be at risk, and are therefore only beneficial if a patient's risk is accurately predicted before he or she sustains a cardiovascular (CV) event. Unfortunately, even relatively accurate risk factor analyses, such as the Reynolds Risk Score algorithm, fail to identify some patients who will sustain a CV event within 10 years. In contrast, the presence of an atheroma is an absolute predictor for the potential of an atherothrombotic event to occur, and it is therefore reasonable to anchor clinical decisions based on this knowledge. Carotid intima-media thickness (CIMT) testing via B-mode ultrasound is a safe, simple, and inexpensive method for evaluating CV risk by measuring the combined thickness of the intimal and medial layers of the arterial wall. Use of CIMT testing can also detect marked thickening of the arterial wall, possibly indicating plaques or atheromas that are associated with accelerated atherosclerotic disease and increased risk for coronary artery disease, myocardial infarction, and stroke. These characteristics make CIMT a practical supplemental method that physicians can use when making decisions. Moreover, the ability of CIMT testing to identify and quantify atherosclerotic disease has led to the adoption of CIMT as a surrogate endpoint in clinical trials, allowing the efficacy of new drugs to be assessed much more rapidly than would be possible by focusing solely on CV event or mortality rates. To date, several trials have provided evidence to indicate that some CVD therapies slow, stop, or reverse the progression of CIMT. Although many of these studies show that changes in CIMT predict future CV events, the value of CIMT testing in CVD risk assessment is still vigorously debated. In this article, we clarify the utility of CIMT testing for risk classification and reexamine its usefulness as a method for assessing therapeutic efficacy.

Rheumatoid arthritis is associated with reduced adiposity but not with unfavorable major cardiovascular risk factor profiles and enhanced carotid atherosclerosis in black Africans from a developing population: a cross-sectional study

Introduction

Rheumatoid arthritis (RA) is characterized by inflamed joint-derived cytokine-mediated high-grade systemic inflammation that enhances cardiovascular metabolic risk and disease in developed populations. We investigated the potential impact of RA on cardiovascular risk factors including systemic inflammation and atherosclerosis, and their relationships in black Africans from a developing population.

Methods

We evaluated demographic features, adiposity indices, major traditional cardiovascular risk factors, circulating C-reactive protein and interleukin-6 concentrations and ultrasound determined carotid intima-media thickness (cIMT) in 274 black Africans; 115 had established RA. Data were analyzed in confounder-adjusted mixed regression models.

Results

The body mass index and waist-height ratio were lower in RA compared to non-RA subjects (29.2 (6.6) versus 33.7 (8.0), P < 0.0001 and 0.58 (0.09) versus 0.62 (0.1), P = 0.0003, respectively). Dyslipidemia was less prevalent in patients with RA (odds ratio (OR) (95% confidence interval (CI) = 0.54 (0.30 to1.00)); this disparity was no longer significant after further adjustment for reduced adiposity and chloroquine use. RA was also not associated with hypertension, current smoking and diabetes. The number of major traditional risk factors did not differ by RA status (1.1 (0.8) versus 1.2 (0.9), P = 0.7). Circulating C-reactive protein concentrations were similar and serum interleukin-6 concentrations reduced in RA (7.2 (3.1) versus 6.7 (3.1) mg/l, P = 0.7 and 3.9 (1.9) versus 6.3 (1.9) pg/ml, P < 0.0001, respectively). The cIMT was 0.700 (0.085) and 0.701 (0.111) mm in RA and non-RA subjects, respectively (P = 0.7). RA disease activity and severity parameters were consistently unrelated to systemic inflammation, despite the presence of clinically active disease in 82.6% of patients. In all participants, adiposity indices, smoking and converting angiotensin inhibitor non-use were associated with increased systemic inflammation, which related to more atherogenic lipid profiles, and circulating low density lipoprotein concentrations were associated with cIMT (partial R = 0.153, P = 0.032); RA did not impact on these relationships (interaction P ≥0.1).

Conclusions

Among black Africans, patients with established RA experience reduced overall and abdominal adiposity but no enhanced major traditional risk factor and atherosclerosis burden. This study further suggests that an absent interleukin-6 release by inflamed RA joints into the circulation may account for this unaltered cardiovascular disease risk.

Rheumatoid arthritis impacts on the independent relationships between circulating adiponectin concentrations and cardiovascular metabolic risk

Adiponectin and leptin are likely involved in the pathophysiology of rheumatoid arthritis (RA) and therefore potential new therapeutic targets. Adiponectin inhibition could be expected to enhance cardiovascular metabolic risk. However, it is unknown whether RA changes the influence of adipokines on cardiovascular metabolic risk. We determined whether RA impacts on the independent relationships of circulating leptin and adiponectin concentrations with cardiovascular risk factors and carotid intima-media thickness (cIMT) in 277 black African subjects from a developing population; 119 had RA. RA impacted on the relationships of adiponectin concentrations with lipid concentrations and blood pressure, independent of confounders including adiposity (interaction P < 0.05). This translated into an association of adiponectin concentrations with more favorable lipid variables including HDL cholesterol (P = 0.0005), non-HDL cholesterol (P = 0.007), and triglyceride (P = 0.005) concentrations, total cholesterol-HDL cholesterol (P = 0.0002) and triglycerides-HDL cholesterol (P = 0.0003) ratios, and higher systolic (P = 0.0006), diastolic (P = 0.0004), and mean blood pressure (P = 0.0007) in RA but not non-RA subjects. Leptin was not associated with metabolic risk after adjustment for adiposity. The cIMT did not differ by RA status, and adipokine concentrations were unrelated to atherosclerosis. This study suggests that leptin and adiponectin inhibition may not alter overall cardiovascular risk and disease in RA.

The carotid artery atherosclerosis burden and its relation to cardiovascular risk factors in black and white Africans with established rheumatoid arthritis: a cross-sectional study

OBJECTIVE

Black Africans currently experience a distinctly low frequency of atherosclerotic cardiovascular disease. Whether this protection persists in those with rheumatoid arthritis (RA) is unknown. We compared the carotid atherosclerosis burden and its relationships with cardiovascular (CV) risk factors between Africans with RA from a developing black and developed CV population.

METHODS

We performed high resolution B-mode ultrasonography and assessed CV risk factors in 243 patients with established RA, of whom 121 were black and 122 white. Data were analyzed in age, sex, and healthcare center-adjusted regression models.

RESULTS

The mean±SD common carotid intima-media thickness (cIMT) was 0.694±0.097 mm in black and 0.712±0.136 mm in white patients (adjusted p=0.8). Plaque prevalence was also similar in black compared to white cases (35.5% and 44.3%, respectively; adjusted OR 0.83, 95% CI 0.32-2.20, p=0.7). Interactions between population grouping and several CV risk factors were independently associated with cIMT and plaque. In stratified analysis, that is, in each population group separately, risk factors associated with cIMT or/and plaque comprised the systolic blood pressure (p=0.02), serum cholesterol/high-density lipoprotein cholesterol ratio (p=0.004), C-reactive protein concentrations (p=0.01), and the presence of extraarticular manifestations (p=0.01) in whites but, contrastingly, the Arthritis Impact Measurement Scales tension score (p=0.04) and use of nonsteroidal antiinflammatory agent (p=0.03) in black patients. The Framingham score was significantly associated with atherosclerosis only in whites (p<0.0001).

CONCLUSION

The carotid atherosclerosis burden is similar in black compared to white Africans with RA, but relationships between modifiable CV risk factors and atherosclerosis vary substantially among Africans with RA.

Obesity and carotid atherosclerosis in African black and Caucasian women with established rheumatoid arthritis: a cross-sectional study

INTRODUCTION

Reported findings on the relationship between adiposity and atherosclerotic cardiovascular disease (ACVD) risk in rheumatoid arthritis (RA) are contradictory and originate in developed populations. Approximately 80% of ACVD now occurs in developing countries. We aimed to ascertain the associations of clinical obesity measures with metabolic cardiovascular risk and atherosclerosis in African women with RA from a developing black and developed Caucasian population.

METHODS

The associations of body mass index (BMI) as an indicator of overall adiposity and waist circumference and waist-to-height and waist-to-hip ratios as abdominal obesity indices with metabolic risk factors and high resolution B-mode ultrasound-determined carotid artery atherosclerosis were assessed in multivariate regression models in 203 African women with established RA; 108 were black and 95 Caucasian.

RESULTS

BMI and waist-to-height ratio were higher in African black compared to Caucasian women (29.9 (6.6) versus 25.3 (4.9) kg/m2, P = 0.002 and 0.59 (0.09) versus 0.53 (0.08), P = 0.01, respectively). Interactions between population origin and anthropometric measures were not related to metabolic risk factors but were associated with atherosclerosis, independent of confounders and individual terms. In all patients, BMI was related to systolic and diastolic blood pressure but not with serum lipid concentrations whereas abdominal obesity indices were associated with serum lipid concentrations but not with blood pressure values; obesity measures that were associated with plasma glucose concentrations comprised BMI, waist circumference and waist-to-height ratio (P < 0.05 in multiple confounder adjusted analysis). In African Caucasian women, BMI was associated with common carotid artery intima-media thickness (standardized β (95% confidence interval (CI)) = 0.21 (0.03 to 0.38)) and waist-to-hip ratio with plaque (odds ratio (OR) (95% CI) = 1.83 (1.03 to 3.25) for one standard deviation (SD) increase). These relationships were independent of multiple non-metabolic risk factors and explained by metabolic risk factors. In African black women with RA, none of the obesity measures was related to atherosclerosis.

CONCLUSIONS

Obesity in women with RA from developing groups of black African descent does not as yet translate into atheroma. In Caucasian women with RA that belong to developed populations, BMI and waist-to-hip ratio should be considered in ACVD risk assessment.

Effects of an office-based carotid ultrasound screening intervention

BACKGROUND

Carotid ultrasound screening (CUS) has been recommended for cardiovascular disease risk prediction, but its effectiveness in clinical practice is unknown. The purpose of this study was to prospectively determine the effects of office-based CUS on physician decision making and patient health-related behaviors.

METHODS

Physicians from five nonacademic, community practices recruited patients aged ≥40 years with ≥1 cardiovascular disease risk factor. Abnormal results on CUS (AbnlCUS) were defined as carotid intima-media thickness >75th percentile or carotid plaque presence. Subjects completed questionnaires before and immediately after CUS and then 30 days later to determine self-reported behavioral changes. Odds ratios (ORs) for changes in physician management and patient health-related behaviors were determined from multivariate hierarchical logistic regression models.

RESULTS

There were 355 subjects (mean age, 53.6 ± 7.9 years; mean number of risk factors, 2.3 ± 0.9; 58% women); 266 (74.9%) had AbnlCUS. The presence of AbnlCUS altered physicians' prescription of aspirin (P < .001) and cholesterol medications (P < .001). Immediately after CUS, subjects reported increased ability to change health-related behaviors (P = .002), regardless of their test results. Subjects with AbnlCUS reported increased cardiovascular disease risk perception (OR, 4.14; P < .001) and intentions to exercise (OR, 2.28; P = .008), make dietary changes (OR, 2.95; P < .001), and quit smoking (OR, 4.98; P = .022). After 30 days, 34% increased exercise frequency and 37% reported weight loss, but these changes were not predicted by the CUS results. AbnlCUS modestly predicted reduced dietary sodium (OR, 1.45; P = .002) and increased fiber (OR, 1.55; P = .022) intake.

CONCLUSIONS

Finding abnormal results on CUS had major effects on physician but not patient behaviors.

Hemostatic cardiovascular risk factors, common carotid-intima medial thickness and peripheral arterial disease in South Asians and African Caribbeans: a substudy to the Ethnic-Echocardiographic Heart of England Screening (E-ECHOES) study

OBJECTIVE

To determine whether ethnic differences exist in inflammatory (interleukin-6 and C-reactive protein) and hemostatic biomarkers (soluble P-selectin [sP-sel], von Willebrand factor [VWF], and fibrin D-dimer) between South Asian (people originating from India, Pakistan, and Bangladesh) and African Caribbean (Black Caribbean and Black African) groups, the two largest minority ethnic groups in the UK; and to determine associations between these biomarkers and common carotid intima-media thickness and peripheral artery disease (PAD).

PATIENTS AND METHODS

We recruited 572 subjects (356 South Asian and 216 Black) aged ≥ 45 years as a substudy to a community screening project, the Ethnic-Echocardiographic Heart of England Screening (E-ECHOES) study. All subjects completed an interviewer-led questionnaire, anthropometric measurements were taken, and blood sampling was performed if consent was granted. Ankle brachial pressure index (ABPI) was calculated, and the common carotid intima-media thickness (CCIMT) was measured. PAD was defined as ABPI < 0.9. ELISA was used to quantify inflammatory and hemostatic biomarkers.

RESULTS

The incidence of hypertension (> 70%) and diabetes (> 27%) was high, but non-significantly different between the two ethnic groups. South Asians had higher platelet count and sP-sel levels than African Caribbeans (P < 0.0001 for both), despite there being no significant difference in antiplatelet medication. African Caribbeans had higher D-dimer levels (P = 0.0052). Among South Asians, VWF correlated with ABPI (P = 0.047) and mean (P = 0.002) and maximum CCIMT (P = 0.011) on univariate analysis, and remained an independent predictor of mean and maximum CCIMT on multivariate analysis with traditional cardiovascular risk factors (P = 0.034 and P = 0.046, respectively). In African Caribbeans, D-dimer levels were was higher in PAD than in normal ABPI participants (P = 0.04), and was associated with ABPI in both univariate analysis (P = 0.014) and multivariate analysis (P < 0.0001) with traditional cardiovascular risk factors.

CONCLUSION

Ethnic differences are evident in inflammatory and hemostatic factors, as well as in their associations with CCIMT and PAD. These may reflect differences in cardiovascular risk factors or pathophysiologic processes that characterize each ethnic group.

Ethnic differences in common carotid intima-media thickness, and the relationship to cardiovascular risk factors and peripheral arterial disease: the Ethnic-Echocardiographic Heart of England Screening Study

OBJECTIVE

To compare the mean and maximum common carotid intima-media thickness (CCIMT) in Blacks (Black Caribbean and Black African) and South Asians (People originating from India, Pakistan and Bangladesh) in a population survey and make associations with established cardiovascular risk factors and peripheral arterial disease (PAD).

PATIENTS AND METHODS

A subset of 492 (293 South Asians and 199 Blacks) out of 572 participants aged ≥ 45 years recruited in a sub-study to the Ethnic-Echocardiographic Heart of England Screening (E-ECHOES) epidemiological study had mean and maximum CCIMT measured. A questionnaire, anthropometric measurements and Ankle Brachial Pressure Index (ABPI) and Intermittent Claudication assessments were made.

RESULTS

Black participants had greater mean but not maximum CCIMT when compared to South Asians overall (P = 0.022), in men (P = 0.04) and in women (P = 0.044). Black ethnicity was an independent predictor of CCIMT even after adjustment for traditional cardiovascular risk factors (P < 0.05). After adjustment for age, ethnicity and traditional cardiovascular risk factors, the presence of PAD remained independently predictive of mean (P = 0.019) and maximum (P = 0.012) CCIMT.

CONCLUSION

Black ethnicity is related to greater mean and maximum CCIMT when compared to South Asians, even after adjusting for traditional cardiovascular risk factors. The presence of PAD independently predicts mean and maximum CCIMT adjusting for ethnicity, age and cardiovascular risk factors.

Carotid intima-media thickness as a surrogate marker of cardiovascular disease in diabetes

BACKGROUND

Diabetes mellitus is associated with a high risk of cardiovascular disease. Carotid intima-media thickness (CIMT) is increasingly used as a surrogate marker for atherosclerosis. Its use relies on its ability to predict future clinical cardiovascular end points.

METHODS

This review examines the evidence linking CIMT as a surrogate marker of vascular complications in people with type 1 and type 2 diabetes. We have also reviewed the various treatment strategies which have been shown to influence CIMT.

CONCLUSIONS

CIMT measurement is an effective, noninvasive tool which can assist in identifying people with diabetes who are at higher risk of developing microvascular and macrovascular complications. It may also help to evaluate the effectiveness of various treatment strategies used to treat people with diabetes.

Carotid intima-media thickness in individuals with and without type 2 diabetes: a reproducibility study

Background

The use of carotid intima-media thickness (carotid IMT) as a surrogate marker of cardiovascular disease is increasing and the method has now also been applied in several trials investigating patients with type 2 diabetes (T2D). Even though knowledge about methodology is of highest importance in order to make accurate power calculations and analyses of results, no reproducibility studies have been performed in this group of patients. The aim of this study was to quantify the variability of the measurement of carotid IMT in individuals with and without T2D.

Methods

We used B-mode ultrasound and a computerized software programme (MIA vascular tools) for analysis of carotid IMT. Measurement of carotid IMT in the far wall of the common carotid artery (CCA) was done for 30 patients with T2D and 30 persons without T2D. The examinations were done by two different sonographers and two different readers on two separate days in order to quantify sonographer-, reader-, and day-to-day variability.

Results

Comparisons of measurement of carotid IMT in CCA between sonographers (sonographer variability) resulted in limits of agreement (LoA) from -0.18 to 0.13 mm for patients with T2D and -0.12 to 0.10 mm for persons without T2D. This means, that a second scanning of the same person with 95% probability would be within this interval of the first scanning. Comparisons between readers assessing the same scanning (reader variability) resulted in LoA from -0.05 to 0.07 mm and -0.04 to 0.05 mm respectively. LoA of the day-to-day variability was -0.13 to 0.18 mm and -0.09 to 0.18 mm respectively. This corresponds to coefficients of variations (CV) of the sonographer- and day-to-day variability of 10% in patients with T2D and 8% in persons without T2D. The CV of the reader variability was 4% and 3% respectively.

Conclusion

Measurement of carotid IMT in the CCA can be determined with good and comparable reproducibility in both patients with T2D and persons without T2D. These findings support the use of carotid IMT in clinical trials with T2D patients and suggest that the numbers of patients needed to detect a given difference will be the same whether the patients have T2D or not.

Carotid intima-media thickness: knowledge and application to everyday practice

Heart disease is the primary cause of death in the United States. Fortunately, intervention measures can reduce the risk of cardiovascular disease (CVD) after a patient has been accurately assessed. Atherosclerotic disease, one of the driving forces behind CVD, is not always detected by traditional risk assessment. Carotid intima-media thickness (CIMT), as measured by B-mode ultrasound, is a surrogate marker for atherosclerosis and can be used to detect an accelerated disease process and subclinical disease. Advantages of CIMT are that it is noninvasive, relatively inexpensive, and can be repeatedly performed with no adverse effects on the patient. Carotid intima-media thickness is associated with CVD and is an independent predictor of stroke and myocardial infarction. Therefore, CIMT is valuable for clarifying CVD risk, particularly for patients with intermediate risk by conventional risk assessment. Screening for subclinical disease even in low-risk patients may have benefit, especially for those with a family history of premature CVD or those with any of the National Cholesterol Education Program risk factors. The detection of subclinical atherosclerosis allows the physician to implement prevention efforts prior to a devastating CVD event and to investigate possible reasons for increased arterial thickening, such as an occult underlying insulin-resistant condition or residual lipid risk markers. Treatment with several types of drugs has been demonstrated to halt the progression or even reduce CIMT. Carotid intima-media thickness is currently limited by the lack of standardized protocols that may affect reproducibility from measure to measure. Efforts to draft a standardized protocol are underway by the Society of Atherosclerosis Imaging and Prevention that will address this issue. Carotid intima-media thickness provides a valuable tool for physicians to clarify the CVD risk of their patients. Practical implications of CIMT for everyday clinical practice are addressed.

Variations in carotid artery intima-media thickness during the cardiac cycle in children

BACKGROUND

There is paucity of research looking at variations in carotid artery intima-media thickness (CIMT) during the cardiac cycle in children. The aim of this study was to ascertain variations, if any, in CIMT during the cardiac cycle in a population of high-risk children.

METHODS

Forty-nine children aged 6 to 19 years with dyslipidemia and other atherosclerosis-promoting risk factors underwent a carotid ultrasound. CIMT was measured using commercially available, semiautomated edge-detection software. The region of interest was the far wall of the common carotid artery. CIMT was measured at various points during the cardiac cycle using the electrocardiogram (EKG) as a reference. CIMT measurements two frames before, during, and after the QRS complex (end diastole) were analyzed separately (designated as "QRS CIMT") from the other CIMT measurements (designated as "non-QRS CIMT"). Demographics, heart rate, blood pressure, anthropometric measures, lumen diameter, family history, and presence of other atherosclerosis-promoting risk factors were documented.

RESULTS

"QRS CIMT" was significantly thicker than "non-QRS CIMT" (P = .01), with the age group 10 to 14 years showing the most significant variation between "QRS CIMT" and "non-QRS CIMT" (P = .005). CIMT values between right and left carotid arteries differed by 2.5%. Age, systolic blood pressure, and blood glucose were significant predictors of mean CIMT by simple linear regression; systolic blood pressure was the only significant predictor of mean CIMT by stepwise multiple linear regression analysis.

CONCLUSION

CIMT measurements vary during the cardiac cycle in children. It is thicker during the QRS complex on EKG. Carotid ultrasound should be performed with an EKG, and CIMT should be measured at the same point on the EKG to overcome this variation. Furthermore, we recommend that CIMT be measured at the R-wave on EKG because this is an easily discernible point in the cardiac cycle.

Ultrasound detection of increased carotid intima-media thickness and carotid plaque in an office practice setting: does it affect physician behavior or patient motivation?

BACKGROUND

The aim of this multicenter study was to determine if identifying increased carotid intima-media thickness (CIMT) or carotid plaque during office-based ultrasound screening examinations could alter physicians' treatment plans and patients' motivation regarding health-related behaviors.

METHODS

Carotid ultrasound studies were performed by a nonsonographer clinician using a handheld system. Changes in physicians' treatment plans and patients' motivation on the basis of scan results were analyzed using multivariate regression.

RESULTS

There were 253 subjects (mean age, 58.1 +/- 6.6 years). When increased CIMT or carotid plaque was detected, physicians were more likely to prescribe aspirin and lipid-lowering therapy (P < .001). Subjects were more likely to report increases in plans to take cholesterol-lowering medication (P = .002) and the perceived likelihood of having or developing heart disease (P = .004).

CONCLUSIONS

Findings from office-based carotid ultrasound studies can influence physicians' prescriptions of evidence-based interventions. Patients with abnormal ultrasound findings recognize their increased cardiovascular risk and plan to take cholesterol-lowering medication.

Carotid Intima-Media Thickness Testing by Non-Sonographer Clinicians: The Office Practice Assessment of Carotid Atherosclerosis Study

BACKGROUND

The purpose of this study was to determine whether a non-sonographer clinician (NSC) could obtain ultrasound images of the carotid artery, measure carotid intima-media thickness (CIMT), and identify findings indicating increased cardiovascular risk in an office setting.

METHODS

Eight NSCs from five sites were trained to use a handheld ultrasound device to screen the carotid arteries for plaques and to measure CIMT.

RESULTS

NSCs scanned 150 subjects who provided 900 images, of which 873 (97%) were interpretable. Differences between NSCs and the core laboratory were small (0.002 +/- 0.004 mm) and bioequivalent (P(TOST) < 0.05) with a low coefficient of variation (3.9% +/- 0.5%). There was > or = 90% agreement on the presence of CIMT > or = 75th percentile and > or = 80% agreement on plaque presence.

CONCLUSIONS

This is the first multicenter study to show that NSCs can obtain images of the carotid arteries using a handheld ultrasound device, accurately measure CIMT, and identify findings indicating increased cardiovascular risk.

Normal Value of Carotid Intima-Media Thickness–A Surrogate Marker of Atherosclersosis: Quantitative Assessment by B-Mode Carotid Ultrasound

BACKGROUND

Carotid intima-media thickness (IMT) is a surrogate marker of atherosclerosis and imparts prognostic information independent of traditional cardiovascular risk factors. Quantitative assessment of IMT using semiautomated border detection software is a new and easy technique that has been previously shown to be accurate, effective, and reproducible. The study is aimed to define the upper limit of carotid IMT at the common carotid artery (CCA) and its bifurcation among a healthy population in the United Kingdom.

METHODS

Asymptomatic men and women aged 35 to 75 years, without evidence of clinical atherosclerosis, underwent B-mode carotid duplex ultrasound (Sonos 7500, Philips, Best, The Netherlands). Mean carotid IMT at the far wall of both left and right CCA were quantitatively determined using a semiautomated edge-detection algorithm (Q-lab 4, Philips). Healthy population was defined as participants with no cardiovascular disease and no evidence of diabetes mellitus or hypertension with a body mass index less than 30 kg/m2, serum cholesterol less than 6 mmol/L, and absence of carotid plaque on ultrasound.

RESULTS

Of the 453 participants, 137 were found to be healthy. IMT measured at the bifurcation was found to be significantly higher compared with that at the CCA. Carotid IMT in both CCA and its bifurcation increased significantly with age. The upper limits (97.5 percentile) of IMT at CCA for participants age 35 to 39, 40 to 49, 50 to 59, and 60 years or older were 0.60, 0.64, 0.71, and 0.81 mm, respectively, whereas for that at bifurcation were 0.83, 0.77, 0.85, and 1.05 mm, respectively.

CONCLUSION

This study demonstrated the value of IMT at CCA and its bifurcation in a healthy population in the United Kingdom using a semiautomated edge-detection software, which is easy to use and reproducible.

Does detection of carotid plaque affect physician behavior or motivate patients?

BACKGROUND

Imaging techniques to identify subclinical atherosclerosis are becoming more widespread, but few data exist regarding their influence on patient or physician behavior. We evaluated the impact of ultrasound screening to identify carotid artery plaques on physician treatment plans and patient motivation.

METHODS

Subjects included asymptomatic patients without known vascular disease who had 2 or more cardiac risk factors. Circumferential scanning of the right and left carotid arteries to identify carotid plaques was performed using a handheld ultrasound device in an office setting. The physician's initial treatment recommendations were assessed before and after the results of the carotid scan were reported. Subjects completed a survey to assess motivation to make lifestyle changes before and after the results of the scan were provided.

RESULTS

Fifty subjects were enrolled over 9 months. Their mean (SD) age was 54.0 (10.4) years and their mean Framingham 10-year cardiovascular risk was 7.8% (7.9%). More than half (58%) of the subjects had at least one carotid plaque. When carotid plaque was identified, physicians were more likely to prescribe aspirin (P = .031) and lipid-lowering therapy (P = .004). Although subjects with carotid plaque reported an increase in their perceived likelihood of developing heart disease (P = .013), they did not report increased motivation to make lifestyle changes.

CONCLUSIONS

Ultrasound screening for carotid plaque in an office setting can alter physician treatment plans. Although the presence of plaque increased patient perception of cardiovascular risk, it did not motivate patients to make lifestyle changes.

An Abbreviated Carotid Intima-Media Thickness Scanning Protocol to Facilitate Clinical Screening for Subclinical Atherosclerosis

BACKGROUND

Carotid intima-media thickness (CIMT) testing can assist with cardiovascular risk prediction; however, the requirement for rigorous, time-consuming protocols has limited it use in clinical practice.

METHODS

Bilateral images of the common carotid artery (CCA), bulb, and internal carotid artery segments were obtained using a comprehensive scanning protocol. Three abbreviated scanning protocols were evaluated for their ability to identify patients with increased CIMT (> or = 75th percentile).

RESULTS

Of 261 subjects, 134 (51.3%) had increased left or right CCA CIMT (CCA protocol), 136 (52.1%) had carotid plaque (plaque protocol), and 190 (72.7%) had plaque or at least one increased CCA CIMT (combination protocol). The area under the receiver-operator characteristic curves for the CCA (0.738) and combination protocols (0.692) were higher than the plaque protocol (0.625, P < .05). The combination protocol was 100% sensitive.

CONCLUSIONS

Compared with a comprehensive scanning protocol, plaque screening with measurement of far wall CCA CIMT identifies all patients with increased CIMT.

The METIS project for generalist ultrasonography

Reorganization of the community healthcare system and the growing presence of group practices in the field of general medicine have increased the demands placed on primary-care medicine, in terms of the skills required and the level of responsibility. Satisfying the need for rapid, effective primary-care solutions to the health problems of citizens is easier thanks to technological and medical advances that provide high level equipment at costs within the reach of general practitioners (GPs). In the near future, trained GPs equipped with appropriate diagnostic scanners will be able to handle up to 40% of the requests of ultrasound examinations of each primary-care group (each PCG includes approximately 15,000-20,000 citizens). The Italian Federation of General Practitioners (Federazione Italiana dei Medici di Medicina Generale - FIMMG) and its Scientific Society, METIS, have organized national courses for those GPs who wish to become generalist ultrasonographers, in a joint effort with the two most important Italian scientific societies of imaging, the Italian Society of Ultrasonology in Medicine and Biology and the Italian Society of Medical Radiology.

Carotid intima-medial thickness measured on multiple ultrasound frames: evaluation of a DICOM-based software system

Background

Carotid intima-media thickness (CIMT) measured by B-mode ultrasonography is a marker of atherosclerosis and is commonly used as an outcome in intervention trials. We have developed DICOM-based software that measures CIMT rapidly on multiple end-diastolic image frames. The aims of this study were to compare the performance of our new software with older bitmap-based CIMT measurement software and to determine whether a ten-fold increase in the number of measurements used to calculate mean CIMT would improve reproducibility.

Methods

Two independent sonographers recorded replicate carotid scans in thirty volunteers and two blinded observers measured CIMT off-line using the new DICOM-based software and older bitmap-based software. A Bland-Altman plot was used to compare CIMT results from the two software programs and t-tests were used to compare analysis times. F-tests were used to compare the co-efficients of variation (CVs) from a standard six-frame measurement protocol with CVs from a sixty-frame measurement protocol. Ordinary least products (OLP) regression was used to test for sonographer and observer biases.

Results

The new DICOM-based software was much faster than older bitmap-based software (average measurement time for one scan 3.4 ± 0.6 minutes versus 8.4 ± 1.8 minutes, p < 0.0001) but CIMT measurements were larger than those made using the alternative software (+0.02 mm, 95%CI 0.01–0.03 mm). The sixty-frame measurement protocol had worse reproducibility than the six-frame protocol (inter-observer CV 5.1% vs 3.5%, p = 0.004) and inter and intra-observer biases were more pronounced in the sixty-frame than the six-frame results.

Conclusion

While the use of DICOM-based software significantly reduced analysis time, a ten-fold increase in the number of measurements used to calculate CIMT did not improve reproducibility. In addition, we found that observer biases caused differences in mean CIMT of a magnitude commonly reported as significant in intervention trials. Our results highlight the importance of good study design with concurrent controls and the need to ensure that no observer drift occurs between baseline and follow-up measurements when CIMT is used to monitor the effect of an intervention.

Reproducibility of sonographic measurement of the substantia nigra

The aim of this study was to evaluate inter-reader, intra-investigator and inter-investigator reproducibility and correlations in the assessment of substantia nigra (SN) echogenicity and area measurement by a physician-sonographer (PS), a sonographic laboratory assistant (SLA) and a physician without sonographic experience (PN). A total of 22 patients with extrapyramidal symptoms were examined using transcranial sonography (TCS). SN images were encoded and evaluated by the three readers. A second TCS examination was performed after 7+/-2 d. A second investigator performed TCS examination 1 mo later. Spearman rank correlation and Pearson's correlation coefficient were used when assessing the agreement between readers. All three readers identified the same 15 patients with SN echogenicity III or more. Inter-reader SN echogenicity and area measurement correlations were r=0.55 to 0.82 and r=0.31 to 0.74 between PS and SLA and r=0.55 to 0.77 and 0.49 to 0.62 between PS and PN, respectively (p<0.05 in all cases). Intra-reader echogenicity and area measurement correlations (r=0.85 to 0.96 and r=0.51 to 0.69) were statistically significant only for PS (p<0.001). All intra- and inter-investigator correlations of SN area measurement (r=0.69 to 0.88 and r=0.5 to 0.61) and SN echogenicity (r=0.64 to 0.92 and r=0.51 to 0.69) were statistically significant (p<0.05). Semiquantitative evaluation of SN echogenicity and area using TCS is highly dependent on the experience of the sonographer. Only an experienced sonographer was able to produce very reproducible results with statistically significant correlations; SLA and PN intra-reader correlations were poor.

Clinical Use of Carotid Intima-Media Thickness: Review of the Literature

Carotid intima-media thickness (CIMT) is a simple and inexpensive tool to assess the cumulative effect of atherosclerotic risk factors and is an independent predictor of future cardiovascular risk. CIMT is commonly used as a surrogate end point in research trials as a marker of atherosclerosis. However, new software programs have made CIMT a clinically practical examination for risk evaluation. CIMT correlates with cardiac risk factors and is an independent predictor of future myocardial infarction and stroke risk. Tests for subclinical atherosclerosis, such as CIMT, will help clinicians to more effectively identify the vulnerable patient who would benefit from aggressive prevention intervention.

Diabetes mellitus and noninvasive imaging of atherosclerosis

With the aging of the baby-boom generation, non-insulin-requiring diabetes mellitus (type 2) has become a worldwide pandemic. The causes of the disease are complex and multifactorial and include genetic disposition, lifestyle choices, abnormal aging processes, and alterations in metabolic processes. The impetus for diagnosing the preclinical effects of diabetes generally has been the individual patient's risk for cardiovascular diseases, heart attack, stroke, and peripheral vascular diseases. This review highlights the newer noninvasive imaging methods designed to provide the early prevention of preclinical atherosclerosis.

Use of carotid intima-media thickness and vascular age to modify cardiovascular risk prediction

BACKGROUND

This study identified predictors of patients for whom carotid artery intima-media thickness (CIMT) measurement and determination of vascular age could change cardiovascular disease (CVD) risk assessment.

METHODS

We studied consecutive patients who were asymptomatic and nondiabetic, referred for ultrasound measurement of CIMT. Individuals with CIMT 75th percentile or greater for age, sex, and race were defined as having advanced subclinical atherosclerosis. CIMT values were converted to vascular age estimates and were used to modify Framingham 10-year CVD risk estimates.

RESULTS

Of 506 patients, 261 (51.6%) were not taking lipid-lowering therapy. Advanced subclinical atherosclerosis was present in 77 (30%). There were 62 patients (23.8%) with a change in CVD risk of 5% or more. Predictors of 5% or more change in CVD risk were systolic blood pressure (P < .001), total/high-density lipoprotein cholesterol ratio (P < .001), and male sex (P < .001). Of the 97 patients at moderate or moderately high risk, 56.7% changed risk classification.

CONCLUSIONS

Measurement of CIMT and determination of vascular age can identify individuals with advanced subclinical atherosclerosis, resulting in clinically meaningful alterations in CVD risk estimates.

Contrast Ultrasound Imaging of the Carotid Artery Vasa Vasorum and Atherosclerotic Plaque Neovascularization

Cardiovascular disease is associated with the aging of the population, obesity, metabolic syndrome, and diabetes. Therefore, it is important to develop non-invasive imaging systems to detect "at-risk" populations. New data suggest that contrast-enhanced ultrasound (CU) imaging of the carotid arteries enhances luminal irregularities (i.e., ulcers and plaques), improves near-wall, carotid intima-media thickness, and uniquely permits direct, real-time visualization of neovasculature of the atherosclerotic plaque and associated adventitial vasa vasorum. With continued clinical investigation, CU imaging of the carotid artery may afford an effective means to non-invasively identify atherosclerosis in "at-risk" populations while providing new standard for therapeutic monitoring.