Impact of cardiovascular risk factors on carotid intima-media thickness: sex differences

Associations between Multiple Health Indicators and Carotid Artery Intima-Media Thickness in A Healthy and Active Elderly Population

The purpose of this study was to examine correlations between health indicators (age, BMI, blood pressure (BP), functional strength (FS), handgrip strength, and predicted VO2 max) and carotid intima-media thickness (cIMT) in an active 50 years+ population. Study participants' mean cIMT was also compared to the cIMT mean of the general population. Health screenings were conducted on 1818 participants at the Huntsman World Senior Games from 2016 to 2019. Pearson's correlations, Spearman's correlations, and ANOVA were performed using SPSS. Weak but significant correlations were evident between cIMT and age (r = 0.283, p < 0.001), systolic BP (r = 0.253, p = 0.001), diastolic BP (r = 0.074, p = 0.016), weight (r = 0.170, p < 0.001), height (r = 0.153, p < 0.001), handgrip L (r = 0.132, p < 0.001), handgrip R (r = 0.074, p < 0.029), and BMI (r = 0.07, p = 0.029); non-significant correlations were evident with predicted VO2 max (r = -0.035, p = 0.382), and FS (r = -0.025, p = 0.597). When controlling for age, systolic BP, and sex, only handgrip L (r = 0.225, p = 0.014) was significantly correlated with cIMT. Mean cIMT for this cohort was lower across all sexes and age-matched groups (cIMT = 0.6967 mm (±0.129)). Physical activity is linked to reduced cIMT. Most health-related indicators in this study were significantly but weakly correlated with cIMT. Additional research is needed before common indicators can be used as a surrogate for cIMT and CVD risk. Results from this study can provide clinicians with additional information to reduce CVD risk through modifiable risk factors. Classic CVD risk factors such as systolic BP and BMI should be considered in patients regardless of lifestyle.

Sonographic assessment of carotid intima-media thickness in healthy young Thai adults

Purpose

Early detection of carotid stenosis can reduce cardiovascular risk. In this study, the maximum-carotid intimamedia thickness (CIMT), the mean-CIMT, and the presence of plaque were examined in healthy young Thai adults. Additionally, correlations between CIMT and cardiovascular risk factors were assessed.

Materials and Methods

Left and right carotid arteries of 302 participants (15-45 years old) were scanned, with CIMT measured at the far walls of the common carotid artery, carotid bulb, and internal carotid artery. Demographics and risk factors were assessed using a questionnaire. Ten random participants were re-scanned after 4 weeks.

Results

The study included 123 (40.70%) male and 179 (59.30%) female participants. The max-CIMT, mean-CIMT, and plaque thickness were 0.400±0.100, 0.403±0.095 and 1.520±0.814 mm, respectively. Male participants had significantly higher CIMT values for nearly all locations and age groups. The right-sided CIMT values were higher for all locations. The carotid bulb had the greatest CIMT values (0.437±0.178 mm), followed by the common (0.403±0.095 mm) and internal (0.361±0.099 mm) carotid arteries. Plaque was present in 18 locations (1.00%), affecting 15 participants (4.97%). These plaques were found in the right carotid bulb (n=9; 0.50%), left carotid bulb (n=7; 0.39%), and right internal carotid artery (n=2; 0.11%). Adjusted multivariable regression revealed significant positive associations between CIMT and male, increased age and "other" occupation (P<0.05).

Conclusion

Both max-CIMT and mean-CIMT were approximately 0.4 mm. Plaque was observed in 4.97% of patients, with an average thickness of 1.5 mm. The most influential risk factors for increased CIMT were sex, age, and occupation.

The Association between Cardiovascular Risk Factors and Carotid Intima-Media Thickness in 42,726 Adults in UK Biobank: A Cross-Sectional Study

BACKGROUND

Traditional modifiable cardiovascular risk factors, such as high blood pressure, have long been positively correlated with high carotid intima-media thickness (cIMT). However, traditional cardiovascular risk factors made a minor contribution to cIMT variance, meaning that other markers may be regarded as independent markers for increasing cIMT.

AIMS

To investigate the simple demographic patterns of carotid intima-media thickness (cIMT) in the UK Biobank and to identify which upstream cardiovascular disease (CVD) risk factors are independently associated with cIMT.

METHODS AND RESULTS

A cross-sectional-based study of healthy middle-aged people recruited in the UK between 2006 and 2010 (n = 42,726).

RESULTS

This study showed that the cardiovascular risk profile generally worsened across the cIMT quantiles from lowest to highest. The lowest cIMT quartile was defined as having a mean cIMT < 588 µm, while the highest cIMT quartile was defined as having a mean cIMT > 748 µm. Specifically, the highest cIMT quantile group had a worse CVD risk factors profile compared to the lowest cIMT quantile group. It was found that, for every one SD increase in age and systolic blood pressure, the mean cIMT increased by 0.357 SD and 0.115 SD, respectively.

CONCLUSION

Systolic blood pressure and age were the strongest independent risk factors for a high cIMT value compared to other risk factors.

Impact of age and sex on the relationship between carotid intima-media thickness and frailty level in the Canadian Longitudinal Study of Aging

BACKGROUND

Carotid intima-media thickness (cIMT) provides an index of arterial injury. Frailty is an indicator of vulnerability to adverse health outcomes. It is unclear whether cIMT is associated with the multi-dimensional frailty index and/or if this relationship is age- or sex-specific. The aim was to determine the impact of age and sex on the relationship between cIMT and frailty level in middle-aged and older adults.

METHODS

Frailty and cIMT data were extracted from the Canadian Longitudinal Study of Aging baseline comprehensive cohort of middle-aged (45-64 years) and older adults (>65 years) (n = 10,209). cIMT was assessed via high-resolution ultrasound. Frailty was determined using a 52-item index. Covariate-adjusted ordinary least squares regressions were conducted separately for middle-aged males (n = 3178), middle-aged females (n = 3125), older males (n = 2031), and older females (n = 1875).

RESULTS

Average cIMTs were larger in older versus middle-aged adults and in males versus females (all, p < 0.001). Average cIMT was positively associated with frailty level in adjusted linear regression models in middle-aged males [adj. R2 = 0.09; β = 0.015 (95 % CI: 0.005-0.026), p = 0.004], middle-aged females [adj. R2 = 0.11; β = 0.040 (95 % CI: 0.025-0.054), p < 0.001], older males [adj. R2 = 0.12; β = 0.019 (95 % CI: 0.004-0.034), p = 0.01], and older females [adj. R2 = 0.11; β = 0.020 (95 % CI: 0.002-0.039), p = 0.03].

CONCLUSION

cIMT was an independent contributor to frailty level regardless of age group (middle-aged/older adults) or sex, with the strongest effect observed in middle-aged females. Our cross-sectional study documents the independent relationship between a marker of cardiovascular function and an increased vulnerability to adverse health outcomes in middle-aged and older males and females.

What Is Hidden Behind The Gender Differences Of Carotid Atherosclerosis?

This review article reveals possible causes that may underlie gender differences of carotid atherosclerosis: vascular anatomy, localization and morphology of atherosclerotic plaques, different effects and prevalence of known risk factors between genders (arterial hypertension, hypercholesterolemia, obesity, smoking, alcohol consumption, depression / stress). A separate place in the review is given to markers of inflammation and the protective effect of female sex hormones.

Sex Differences in Vascular Aging and Impact of GPER Deletion

Aging is a nonmodifiable risk factor for cardiovascular disease associated with arterial stiffening and endothelial dysfunction. We hypothesized that sex differences exist in vascular aging processes and would be attenuated by global deletion of the G protein-coupled estrogen receptor. Blood pressure was measured by tail cuff plethysmography, pulse wave velocity (PWV) and echocardiography were assessed with high resolution ultrasound, and small vessel reactivity was measured using wire myography in adult (25 weeks) and middle-aged (57 weeks) male and female mice. Adult female mice displayed lower blood pressure and PWV, but this sex difference was absent in middle-aged mice. Aging significantly increased PWV but not blood pressure in both sexes. Adult female carotids were more distensible than males, but this sex difference was lost during aging. Acetylcholine-induced relaxation was greater in female than male mice at both ages, and only males showed aging-induced changes in cardiac hypertrophy and function. GPER deletion removed the sex difference in PWV as well as ex vivo stiffness in adult mice. The sex difference in blood pressure was absent in KO mice and was associated with endothelial dysfunction in females. These findings indicate that the impact of aging on arterial stiffening and endothelial function is not the same in male and female mice. Moreover, nongenomic estrogen signaling through GPER impacted vascular phenotype differently in male and female mice. Delineating sex differences in vascular changes during healthy aging is an important first step in improving early detection and sex-specific treatments in our aging population.

Association Between Retinal Microvascular Metrics Using Optical Coherence Tomography Angiography and Carotid Artery Stenosis in a Chinese Cohort

Objectives: The main aim was to investigate the association between retinal microvascular metrics using optical coherence tomography angiography (OCTA) and carotid artery stenosis (CAS) in an aging Chinese cohort.

Methods: In this cross-sectional and observational study, 138 eyes of 138 participants were examined. Indices of the microcirculation measured by OCTA included mean vessel density (VD), skeleton density (SD), vessel diameter index (VDI), fractal dimension (FD) and foveal avascular zone (FAZ) of the superficial retinal layer (SRL) and deep retinal layer (DRL), and peripapillary vessel caliber. The correlation of these indices with the carotid atherosclerotic lesions including carotid intima media thickness (CIMT) and common carotid artery (CCA) plaque was assessed.

Results: A total of 72 of 138 eyes demonstrated an increased (≥1 mm) CIMT, and 32 of the eyes presented common carotid plaques. Macular VD, SD, and FD were decreased with the increasing CCA caliber diameter (p &lt; 0.05, respectively). Superficial and deep macular FDs were negatively associated with CIMT as well as the existence of CCA plaques (p &lt; 0.05, respectively).

Conclusion: Changes in retinal microvasculature accessed by OCTA may be used as one of the non-invasive early indicators to monitor asymptomatic CAS.

The Role of Physical Activity Status in the Relationship between Obesity and Carotid Intima-Media Thickness (CIMT) in Urban South African Teachers: The SABPA Study

Globally, the prevalence of physical inactivity and obesity are on the rise, which may increase carotid intima-media thickness (CIMT) as a marker of subclinical atherosclerosis. This study assessed the association between physical activity (PA), obesity, and CIMT. A cross-sectional study design was used, including a sub-sample (n = 216) of teachers who participated in the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SAPBA) study. Measurements included the following: physical activity status (measured with ActiHeart devices over 7 consecutive days), body mass index (BMI), waist circumference (WC), waist-to-height ratio (WtHR), CIMT (measured by SonoSite Micromax ultrasound), blood pressure (BP), fasting C-reactive protein (CRP), and cholesterol and glucose levels. Data were analysed using the Statistical Package for Social Science. One-third of the teachers were physically inactive (33%) and had low-grade inflammation CRP ≥ 3 mg/L (41%). Males were more sedentary and had higher BP and CIMT (p < 0.05). Independent of age and sex, WC or central obesity was 2.63 times more likely (p = 0.02) to contribute to atherosclerosis, especially in females (OR: 4.23, p = 0.04). PA levels were insignificantly and negatively (β −0.034; 0.888; 0.240) related to subclinical atherosclerosis. The cardiovascular disease risk profiles and limited PA status may have curbed the beneficial impact of PA on the obesity and atherosclerosis.

Hemodynamic characteristics and early warnings in very old patients

The hemodynamic characteristics of very old patients (VOPs) are unique. With increasing age, patients may experience reduced diastolic function, increased rates of valvular heart disease and coronary atherosclerosis, stiffer vessels, and a reduced heart response to stimulations. Structural and functional modifications are linked to cardiac aging; echocardiography reveals concentric remodeling of the left ventricle, dilation of the left atrium, thickening and calcification of the valves, modification of the large vessels, and abnormal ventricular relaxation. According to a comprehensive understanding of the insufficient compensatory mechanisms of the aging heart, arrythmia should be avoided to the maximum extent and "conservative" fluid therapy should be provided together with appropriate blood pressure control. Considering these factors will improve the success rate of resuscitation and significantly reduce economic loss. In addition, more attention should be paid to the diastolic blood pressure in VOPs.

Possible Gender Difference in the Association Between Abdominal Obesity, Chronic Inflammation, and Preclinical Atherosclerosis in the General Population

Chronic inflammation due to abdominal obesity plays a major role in the development of cardiovascular disease (CVD). Gender differences are well characterized in the development of CVD; however, in the association among abdominal obesity, chronic inflammation, and preclinical atherosclerosis, gender differences in the general population remain to be clarified. We retrospectively analyzed 1,163 subjects who underwent voluntary health checkups at our institute. We defined carotid artery plaque formation as carotid intima-media thickness ≥ 1.1 mm. Multiple regression analysis showed that waist circumference was a major independent predictor of increase in serum C-reactive protein (CRP) level in both men and women. Serum CRP level was significantly increased in men with carotid artery plaque formation, but not in women. Multivariable logistic regression analysis demonstrated that serum CRP level, as well as age and hypertension, was independently associated with carotid artery plaque formation only in men. This result may suggest a potential of gender-specific difference in the association between serum CRP level and the prevalence of carotid artery plaque formation. Further investigations are required to confirm our results and to clarify the underlying mechanism.

Do individuals with autoimmune disease have increased risk of subclinical carotid atherosclerosis and stiffness?

To explore the role of chronic inflammation inherent to autoimmune diseases in the development of subclinical atherosclerosis and arterial stiffness, this study recruited two population-based samples of individuals with and without autoimmune disease (ratio 1:5) matched by age, sex, and education level and with a longstanding (≥6 years) diagnosis of autoimmune disease. Common carotid intima-media thickness (IMT) and arterial distensibility and compliance were assessed with carotid ultrasound. Multivariable linear and logistic regression models were adjusted for 10-year cardiovascular risk. In total, 546 individuals with and without autoimmune diseases (91 and 455, respectively) were included. The mean age was 66 years (standard deviation 12), and 240 (43.9%) were women. Arterial stiffness did not differ according to the presence of autoimmune diseases. In men, the diagnosis of autoimmune diseases significantly increased common carotid IMT [beta-coefficient (95% confidence interval): 0.058 (0.009; 0.108); p value = 0.022] and the percentage with IMT ≥ 75th percentile [1.012 (0.145; 1.880); p value = 0.022]. Women without autoimmune disease were more likely to have IMT ≥ the 75th percentile [-2.181 (-4.214; -0.149); p value = 0.035], but the analysis of IMT as a continuous variable did not yield significant results. In conclusion, subclinical carotid atherosclerosis, but not arterial stiffness, was more common in men with autoimmune diseases. Women did not show significant differences in any of these carotid features. Sex was an effect modifier in the association between common carotid IMT values and the diagnosis of autoimmune diseases.

Prevalence of asymptomatic atherosclerosis of extracranial vessels among hypertensive patients in southern Egypt: An extracranial duplex study

Objectives:

The prevalence of atherosclerosis in extracranial vessels among hypertensive patients in southern Egypt is still unknown. Carotid ultrasound is an accurate method used to identify and follow patients with cerebrovascular disorders. The aim of our study is to detect the prevalence and pattern of extracranial atherosclerosis among those patients.

Methods:

Our case-control study was performed from January 2017 to January 2018, including 200 subjects, 100 patients recruited consecutively from the Hypertension Clinic in Assiut University hospitals, Egypt, and 100 healthy controls. Detailed history collection and thorough physical examinations were carried out for each patient. All subjects underwent extracranial ultrasound. We omitted patients with history of ischemic stroke and TIAs.

Results:

The presence of increased intima media thickness was detected in 37 patients (37%). 22 patients (22%) had internal carotid artery (ICA) stenosis, 17 patients (17%) had non-significant stenosis <50%, while five patients (5%) had stenosis 50-69%. 9% had stenosis < 50% in vertebral artery. In addition, age and uncontrolled hypertension have a greater impact on increasing the CCA intima media thickness, which is considered an early sign of atherosclerosis.

Conclusions:

Uncontrolled hypertension is an important risk factor for atherosclerosis and hence ischemic stroke (IS). The cost of screening is considered low compared to IS management. Greater emphasis should be directed toward regular screening programs in this risky population.

Sex -Specific Differences in the Association Between Metabolic Syndrome and Carotid Intima-Media Thickness Among a Low-Income Population in China: A Cross-Sectional Study

INTRODUCTION

Carotid atherosclerosis is a well-established biomarker associated with future cardiovascular disease and stroke. We explored the influence of sex on the relationship between metabolic syndrome (MetS) and its components with carotid intima-media thickness (CIMT) among a low-income population in China, which has a high incidence of stroke.

METHODS

This population-based study recruited participants aged ≥45 years from rural areas of Tianjin, China between April 2014 and January 2015. Anthropometric characteristics and biochemical profiles were measured. CIMT was assessed using ultrasonography. Diagnosis of MetS and its components was made using the modified International Diabetes Federation criteria for the Asian population. A multivariate linear regression model was used to evaluate the effects of sex on the relationship between the presence of MetS and its components and CIMT.

RESULTS

A total of 3583 individuals (men, 41.4%; women, 58.6%) were included in the analyses. MetS was prevalent in 54.5% (men, 42.3%; women, 63.2%) of the participants. Mean CIMT was 0.57 ± 0.09 mm. In the multivariate analysis, for both sexes, CIMT increased significantly when MetS was present compared with when it was not (both P < 0.001). A common trend was observed in both sexes, in that CIMT increased as the number of MetS components increased, with β (95% confidence interval [CI]) = 0.021 (0.000, 0.042) for men and 0.014 (0.002, 0.026) for women (both P < 0.05). Of the five MetS components, elevated blood pressure was an independent risk factor for increased CIMT in both sexes (men: β = 0.013; 95% CI: 0.003, 0.023; P = 0.008; women: β = 0.024; 95% CI: 0.016, 0.033; P < 0.001). Moreover, abdominal obesity was also an independent risk factor for increased CIMT in men (β = 0.013; 95% CI: 0.003, 0.023; P = 0.008) but not in women.

CONCLUSION

The presence and number of components of MetS were associated with CIMT in both men and women. Sex differences were found in the impact of individual components of MetS on CIMT. Early identification and management of MetS according to sex-specific risk of MetS should be considered to reduce the prevalence and burden of carotid atherosclerosis in rural China, which has a high incidence of stroke, a known consequence of carotid atherosclerosis.

Subclinical macro and microvascular disease is differently associated with depressive symptoms in men and women: Findings from the SABRE population-based study

BACKGROUND AND AIMS

Mechanisms underlying the association between cardiovascular disease (CVD) and depression are unknown, and sex differences understudied. We investigated associations between a comprehensive set of measures of macro and microvascular disease and depressive symptoms in older men and women.

METHODS

We performed cross-sectional analyses of the SABRE (Southall And Brent REvisited) population-based study. Participants (1396) attended clinic between 2008 and 2011 for assessment of subclinical macrovascular (carotid ultrasound, echocardiography, cerebral magnetic resonance imaging) and microvascular (retinopathy, nephropathy) disease, and depression.

RESULTS

Mean age of 1396 participants was 69.5 years, and 76.2% were male. The median (interquartile range) of depression score was 1 [0, 2] for men and 1 [0, 3] for women. All measures of subclinical macro and microvascular disease were adversely associated with depressive symptoms, even when known CVD was excluded. Physical activity partly explained some of these relationships. The association between left atrial dimension index (LADI), a measure of chronic elevated left ventricular filling pressure, and depressive symptoms was stronger in women (regression coefficient 0.23 [95% CI 0.11, 0.35]) than men (0.07 [-0.01, 0.15]), p for interaction 0.06, on multivariable adjustment.

CONCLUSIONS

Subclinical macro and microvascular disease is associated with depressive symptoms, even in the absence of established CVD. These were in part accounted for by physical activity. We observed stronger association between LADI and depressive symptoms in women than in men. The beneficial role of physical activity in abrogating the association between subclinical CVD and depression warrants further investigation.

Controlling the thickness of the atherosclerotic plaque by statin medication

Atherosclerosis, a chronic inflammatory disorder of the arterial wall, is a complex process whose dynamics are affected by multiple factors. The disease control consists of restraining it by administering statins. Slowing down or halting the plaque growth depends on the patient age at which the statin treatment begins and on the thickness of the intima-media (IMT) at that time. In this paper, we propose a mathematical model to estimate the sets of atherosclerosis states, from which the use of statins can restrain the disease. Our model is control-theoretic, and the estimated sets are the viability kernels, in the parlance of viability theory. To our best knowledge, this way of modelling the atherosclerosis progression is original. We compute two viability kernels, each for a different statin-treatment dose. Each kernel is composed of the vector [age, IMT] from which the disease can be restrained. By extension, the disease can’t be restrained from the kernel complements, this being mainly because of the disease and patient-age advancement. The kernels visualise tradeoffs between early and late treatments, which helps the clinician to decide when to start the statin treatment and which statin dose may be sufficient.

Carotid intima-media thickness and metabolic syndrome in a rural population: Results from the Baependi Heart Study

Background and aims

Carotid intima-media thickness (cIMT) is a strong predictor of cardiovascular events and associated with metabolic syndrome (MetS). MetS is a cluster of cardiovascular risk factors, but the association structure between specific factors and disease development is not well-established in rural populations. We described the association structure between MetS factors and cIMT in a sample from rural Brazil.

Methods

We studied 1937 participants from the Baependi Heart Study who underwent carotid ultrasound exam. We used ATP–III–2001 for MetS definition and linear mixed-effects models, adjusting by the family structure, to assess independent associations between the cardiovascular risk factors which define MetS and cIMT.

Results

The sample's mean age was 46 ± 16y, 61% female, 73% white, mean body-mass-index 26±5 kg/m², mean cIMT 0.53 ± 0.16 mm, with 35% of the sample classified with MetS. As expected, cIMT demonstrated a linear relationship with increasing age, and cIMT higher values were observed for MetS (0.58 ± 0.16 mm) compared to non-MetS (0.49 ± 0.14 mm). Considering models for cIMT with MetS and all of its factors, we found that blood pressure, glucose and obesity were independently associated with cIMT, but not HDL or triglycerides.

Conclusions

cIMT showed a linear relationship with increasing age. Blood pressure, obesity, and glucose were independently associated with cIMT, but not HDL-cholesterol or triglycerides. In a rural population, hypertension, diabetes and obesity play a more important role than lipids in determining cIMT interindividual variability.

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Metabolic Syndrome (MetS) is independently associated with cIMT in a rural sample.

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Age showed a linear relationship with cIMT.

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Blood pressure, glucose, and obesity measurements are independently associated with cIMT, but not cholesterol fractions.

Associations of Arterial Stiffness and Carotid Atherosclerosis with Cerebral Small Vessel Disease in a Rural Community-Based Population

AIMS

We aimed to examine the associations of four extracranial artery indicators with cerebral small vessel disease (CSVD) and its total burden.

METHODS

A total of 904 individuals aged 55-65 years old were included from the Taizhou Imaging Study. CSVD markers, including lacunes (LAC), white matter hyperintensities (WMH), cerebral microbleeds (CMB), and perivascular spaces (PVS), were rated based on brain magnetic resonance imaging. We also measured extracranial artery indices, including the brachial-ankle pulse wave velocity (baPWV), the ankle-brachial index, the carotid intima-media thickness (IMT), and carotid plaque. Linear and binary logistic regressions were adopted to test the associations among these four artery indicators and each CSVD marker when appropriate. Additionally, ordinal and multinomial logistic regressions were performed to assess the relationships between artery indicators and total CSVD score (range from 0-4 points).

RESULTS

A total of 443 (49.0%) participants were found to have at least one of the CSVD markers, including 172 (19.0%) with WMH, 184 (20.4%) with LAC, 147 (16.3%) with CMB, and 226 (25.0%) with PVS. Increased baPWV was significantly associated with each CSVD marker, increasing carotid IMT was associated with LAC and PVS, and the presence of carotid plaque was associated with WMH volume and PVS. Moreover, per SD increment of baPWV (odds ratio [OR]: 1.29, 95% confidence interval [CI]: 1.11-1.50) and the presence of carotid plaque (OR: 1.42, 95% CI: 1.05-1.92) were significantly associated with greater total CSVD scores.

CONCLUSION

Increased baPWV and the presence of carotid plaque appear to be associated with total CSVD burden in rural regions in China.

Race and sex-based disparities associated with carotid endarterectomy in the Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND AND AIMS

The indications for carotid endarterectomy (CEA) are well established. The aim of the current study was to investigate sex and race-based disparities in the incidence of CEA after adjusting for carotid artery stenosis risk factors.

METHODS

We conducted a prospective cohort analysis of 14,492 black and white participants in the Atherosclerosis Risk in Communities (ARIC) study without prevalent stroke at baseline (1987-1989). We used Kaplan-Meier curves and Cox proportional hazards models adjusting for sociodemographic, cardiovascular, and disease severity risk factors to quantify the associations of sex and race with incident CEA.

RESULTS

CEA was performed in 330 of 14,492 ARIC participants during a median of 27 years of follow-up [incidence rate 1.00 (95% CI 0.90-1.12) per 1000 persons-years]. The crude incidence of CEA varied significantly by sex [female vs. male: HR 0.60 (95% CI 0.48-0.74)] and race [black vs. white: HR 0.65 (95% CI 0.49-0.86)]. Adjustment for sociodemographic and cardiovascular risk factors, carotid intima-media thickness, and symptomatic status attenuated the association of sex with CEA [females vs. males HR 0.96 (0.76-1.22)], but black participants had a lower risk of incident CEA after adjustment [HR 0.68 (95% CI 0.49-0.95)].

CONCLUSIONS

We found significant variation in the incidence of CEA procedures based on race that was independent of traditional risk factors and carotid IMT. Whether this disparity is a reflection of differences in disease presentation or access to care deserves investigation.

Classical Cardiovascular Risk Factors and HIV are Associated With Carotid Intima-Media Thickness in Adults From Sub-Saharan Africa: Findings From H3Africa AWI-Gen Study

Background Studies on the determinants of carotid intima-media thickness ( CIMT ), a marker of sub-clinical atherosclerosis, mostly come from white, Asian, and diasporan black populations. We present CIMT data from sub-Saharan Africa, which is experiencing a rising burden of cardiovascular diseases and infectious diseases. Methods and Results The H3 (Human Hereditary and Health) in Africa's AWI-Gen (African-Wits-INDEPTH partnership for Genomic) study is a cross-sectional study conducted in adults aged 40 to 60 years from Burkina Faso, Kenya, Ghana, and South Africa. Cardiovascular disease risk and ultrasonography of the CIMT of right and left common carotids were measured. Multivariable linear and mixed-effect multilevel regression modeling was applied to determine factors related to CIMT. Data included 8872 adults (50.8% men), mean age of 50±6 years with age- and sex-adjusted mean (±SE) CIMT of 640±123μm. Participants from Ghana and Burkina Faso had higher CIMT compared with other sites. Age (β = 6.77, 95%CI [6.34-7.19]), body mass index (17.6[12.5-22.8]), systolic blood pressure (7.52[6.21-8.83]), low-density lipoprotein cholesterol (5.08[2.10-8.06]) and men (10.3[4.75- 15.9]) were associated with higher CIMT. Smoking was associated with higher CIMT in men. High-density lipoprotein cholesterol (-12.2 [-17.9- -6.41]), alcohol consumption (-13.5 [-19.1--7.91]) and HIV (-8.86 [-15.7--2.03]) were inversely associated with CIMT. Conclusions Given the rising prevalence of cardiovascular diseases risk factors in sub-Saharan Africa, atherosclerotic diseases may become a major pan-African epidemic unless preventive measures are taken particularly for prevention of hypertension, obesity, and smoking. HIV -specific studies are needed to fully understand the association between HIV and CIMT in sub-Saharan Africa.

The effect of sex and menopause on carotid intima-media thickness and pulse wave velocity in morbid obesity

BACKGROUND

Women are relatively protected from cardiovascular disease compared with men. Since morbid obesity is an independent risk factor for cardiovascular disease, the current study investigated whether the association between sex and cardiovascular risk factors and outcomes can be demonstrated in subjects suffering from morbid obesity.

MATERIALS AND METHODS

Two hundred subjects enrolled in a study on cardiovascular risk factors in morbid obesity underwent extensive laboratory screening, carotid intima-media thickness (cIMT) and pulse wave velocity (PWV) measurements. Gender differences were analysed using univariate and multivariable linear regression models. In addition, the effect of menopause on cIMT and PWV was analysed. Results of these models were reported as B coefficients with 95% confidence intervals.

RESULTS

The group consisted of 52 men and 148 women, with a mean age of 41 (±11.8) years and a mean body mass index (BMI) of 42.7 (±5.2) kg/m² . Both, cIMT and PWV were significantly higher in men than in women, although the difference in cIMT disappeared after adjustment for covariables such as waist circumference, age, high-density lipoprotein cholesterol and mean arterial pressure. PWV was associated with sex after adjustments for covariables in morbidly obese patients. Postmenopausal women had significantly increased cIMT and PWV when compared with premenopausal women.

CONCLUSION

Sex differences in PWV persist in subjects suffering from morbid obesity. However, no difference was found in cIMT between morbidly obese men and women after adjustment for classic cardiovascular risk factors. Premenopausal morbidly obese women are protected for cardiovascular disease when compared with postmenopausal morbidly obese women.

A Control-Theoretic Model of Atherosclerosis

We propose a control-theoretic aggregate model of the progression of atherosclerosis plaque, a chronic inflammatory disease of the arterial wall, to study the basic features of this disease. In the model, we exploit the role of inflammation in the disease progression, and use statins-drugs commonly recommended in atherosclerosis-to control this progression. We use a logistic function to allow for constrained growth of plaque. In the model, both the patient's age and overall health impact the plaque growth and its sensitivity to statins. The model parameters are estimated using original data, or calibrated using published research as well as our own clinical and laboratory studies. We contend that our model helps to gauge the statins' impact on a patient's plaque thickness, hence the disease's progression and cardiovascular risk, without requiring artery scans.