Ultrasonographic measurement of the common carotid artery wall thickness in hypercholesterolemic patients. A new model for the quantitation and follow-up of preclinical atherosclerosis in living human subjects

Subclinical Atherosclerosis and Incipient Regional Myocardial Dysfunction in Asymptomatic Individuals

OBJECTIVES

This study sought to determine whether increased carotid intima-media thickness (IMT) is related to reduced regional myocardial function in participants of the Multi-Ethnic Study of Atherosclerosis (MESA).

BACKGROUND

Carotid artery IMT is an established index of subclinical atherosclerosis, and tagged magnetic resonance imaging (MRI) can detect incipient alterations of segmental function that precede overt myocardial failure.

METHODS

The MESA study is a prospective observational study including four ethnic groups free from clinical cardiovascular disease. Peak midwall systolic circumferential strain (ECC) and regional strain rates were calculated by harmonic phase from tagged MRI data of 500 participants. Systolic ECC and diastolic strain rate were regressed on IMT of the common carotid artery defined by ultrasound, with adjustments for body mass index, blood pressure, cholesterol, diabetes, smoking, left ventricular hypertrophy, C-reactive protein, age, and gender.

RESULTS

The mean participant age was 66 +/- 10 years (mean +/- SD). Among the 58 participants, 4% were male and the interquartile (25th to 75th percentile) range for IMT was 0.25 mm. Multiple linear regression analyses showed that increased IMT was related to reduced systolic regional function (less shortening ECC) in all myocardial regions (p < 0.05), except in the inferior wall. The analyses also showed that greater IMT was associated with a lower diastolic strain rate (diastolic reduced function) in all regions (p < 0.01), except in the anterior wall.

CONCLUSIONS

Greater carotid IMT is associated with alterations of myocardial strain parameters reflecting reduced systolic and diastolic myocardial function. These observations indicate a relationship between subclinical atherosclerosis and incipient myocardial dysfunction in a population free of clinical heart disease.

Atherosclerosis in women with endometriosis

OBJECTIVE

This study aims to determine whether women with endometriosis have greater subclinical atherosclerosis than the general population.

STUDY DESIGN

This case-control study included 66 women with endometriosis and 66 controls matched for age and body mass index. All subjects were >or=35 years old. Exclusion criteria were obesity, diabetes, hypertension, hyperlipidemia, renal or metabolic diseases. Before laparoscopy, all patients underwent a measurement of intima-media thickness (IMT) and distensibility coefficient (DC) on the common carotid artery. In addition, blood samples were taken to determine the levels of lipids, fibrinogen, C-reactive protein, homocysteine, fasting glycemia, antithrombin III, plasminogen, protein C, protein S, and activated protein C resistance.

RESULTS

All the biochemical parameters evaluated had similar levels in the two study groups. IMT was similar in women with endometriosis and in controls both on left (p=0.330) and right (p=0.648) carotid artery. Similarly, no significant difference was observed in the DC between women with endometriosis and controls both on left (p=0.539) and right (p=0.178) carotid artery. No significant difference was observed in IMT and DC between women with mild and severe endometriosis.

CONCLUSION

Women with endometriosis do not have more subclinical atherosclerosis than the general population.

Normative values of carotid artery intima-media thickness in healthy Korean adults and estimation of macrovascular diseases relative risk using this data in type 2 diabetes patients

The objectives of this study were to determine normative values of carotid intima-media thickness (IMT) in healthy Korean subjects and to use these values to estimate the relative risk of macrovascular diseases in patients with type 2 diabetes mellitus (T2DM). High-resolution B-mode ultrasonography was performed in 1,229 healthy subjects and 830 T2DM patients. Height, weight, blood pressure, fasting plasma glucose, total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol, and fasting insulin level were measured. Subjects were classified as healthy subjects; T2DM patients without ischemic heart disease (IHD), stroke, and peripheral arterial occlusive diseases (PAOD); T2DM patients with IHD, stroke, or PAOD. IMT was significantly increased as age increased. Patients with T2DM had higher IMTs compared to healthy subjects. Independent risk factors of IMT were age, systolic blood pressure, BMI for healthy subjects, and age, duration of diabetes, LDL-cholesterol for T2DM subjects. According to presence of increased IMT, the relative risks of IHD, stroke, and PAOD in diabetic subjects, were 2.34 (CI; 1.32-4.14), 2.95 (CI; 1.46-5.54), and 3.64 (CI; 1.66-7.40), respectively. This study suggests normative values that can be used as an index for carotid artery IMT of healthy Korean subjects, and that IMT data reflects the risk of macrovascular diseases in T2DM.

Vasculoprotective properties of the endothelial glycocalyx: effects of fluid shear stress

The endothelial glycocalyx exerts a wide array of vasculoprotective effects via inhibition of coagulation and leucocyte adhesion, by contributing to the vascular permeability barrier and by mediating shear stress-induced NO release. In this review, we will focus on the relationship between fluid shear stress and the endothelial glycocalyx. We will address the hypothesis that modulation of glycocalyx synthesis by fluid shear stress may contribute to thinner glycocalyces, and therefore more vulnerable endothelium, at lesion-prone sites of arterial bifurcations. Finally, we will discuss the effects of known atherogenic stimuli such as hyperglycaemia on whole body glycocalyx volume in humans and its effect on endothelial function.

Decreased high-density lipoprotein (HDL) particle size, prebeta-, and large HDL subspecies concentration in Finnish low-HDL families: relationship with intima-media thickness

OBJECTIVE

High-density lipoprotein (HDL) cholesterol correlates inversely with the risk of coronary heart disease (CHD). The precise antiatherogenic mechanisms of HDL subspecies are not thoroughly elucidated. We studied the relationship between carotid intima-media thickness (IMT) and HDL subspecies distribution in Finnish families with low HDL cholesterol and premature CHD.

METHODS AND RESULTS

Altogether, 148 members of Finnish low-HDL families and 133 healthy control subjects participated in our study. HDL particle size was significantly smaller in affected family members (HDL < or =10th Finnish age-sex specific percentile) compared with unaffected family members and control subjects (9.1+/-0.04 nm versus 9.5+/-0.05 nm, P<0.0001, versus 9.8+/-0.03 nm, P<0.0001 [mean+/-SE]). Large HDL2b particles as well as prebeta-HDL concentration were significantly decreased among the affected family members. Mean IMT was significantly higher in the affected family members than in the control subjects (0.85+/-0.01 mm versus 0.79+/-0.01 mm; P<0.0001). Age, HDL2b, systolic blood pressure, and prebeta-HDL were significant independent determinants of mean IMT.

CONCLUSIONS

The decreased levels of HDL2b and prebeta-HDL reflect the potentially efflux-deficient HDL subspecies profile in the affected low-HDL family members. Decreased HDL particle size caused by the decrease of plasma concentration of HDL2b and decreased prebeta-HDL levels correlate with increased IMT.

Atherogenic region and diet diminish glycocalyx dimension and increase intima-to-media ratios at murine carotid artery bifurcation

It was hypothesized that endothelial glycocalyx perturbation contributes to increased vulnerability of the arterial wall exposed to atherogenic risk factors. Glycocalyx and intima-to-media ratios (IMR) were studied at a low- and a high-risk region within the murine carotid artery (common region) and internal carotid branch (sinus region) in control C57BL/6J (C57BL6) and age-matched C57BL/6J/apoE*3-Leiden (apoE*3; on an atherogenic diet) mice. Electron micrographs revealed significantly thinner glycocalyces [73 (SD 36) vs. 399 (SD 174) nm, P < 0.05] and greater IMR [0.096 (SD 0.045) vs. 0.044 (SD 0.023), P < 0.05] at the sinus region of C57BL6 mice than in the common region. Thinner glycocalyces [100 (SD 27) vs. 399 (SD 174) nm, P < 0.05] and greater IMR [0.071 (SD 0.024) vs. 0.044 (SD 0.023), P < 0.05] were also observed in the common region of age-matched apoE*3 mice on an atherogenic diet for 6 wk vs. C57BL6 mice on a normal diet. Greater IMR were due to greater intima layers, without significant changes in media layer dimension. In addition, atherogenic diet resulted in increased endothelial cell thickness at the sinus region [0.85 (SD 0.49) vs. 0.53 (SD 0.28) μm, P < 0.05] but not at the common region [0.66 (SD 0.37) vs. 0.62 (SD 0.32) μm]. It is concluded that both regional and diet-induced increases in atherogenic risk are associated with smaller glycocalyx dimensions and greater IMR and that vascular sites with diminished glycocalyx are more vulnerable to proinflammatory and atherosclerotic sequelae.

Effect of n-3 fatty acids on carotid atherosclerosis and haemostasis in patients with combined hyperlipoproteinemia: a double-blind pilot study in primary prevention

BACKGROUND

Intake of n-3 polyunsaturated fatty acids (n-3 PUFA) either from natural sources or dietary supplementation is inversely associated with atherothrombosis.

AIM

A double-blind pilot study was designed to address the impact of n-3 PUFA on atherosclerosis, haemostasis and vascular status in patients with combined hyperlipoproteinemia.

METHODS

Carotid intima-media thickness (C-IMT), texture of intima-media complex (T-IMC), lipids and platelet function were evaluated in 64 patients with combined hyperlipoproteinemia who received placebo or n-3 PUFA (6 g/day) for 2 years. C-IMT and T-IMC were assessed by B-mode ultrasound. Lipids and platelet function were determined by validated methods.

RESULTS

C-IMT increased in placebo, but not in n-3 PUFA group with respect to baseline. In contrast T-IMC decreased in n-3 PUFA, but not in placebo; in both cases, however, treatment effect did not reach statistical significance. A fall of triglycerides, concomitant to a rise of high- and low-density lipoprotein cholesterol (HDL and LDL), was observed in the active treated group. Platelet function was significantly reduced by n-3 PUFA.

CONCLUSIONS

Results show a favourable effectiveness of n-3 PUFA on IMT progression and T-IMC that deserves to be confirmed in larger studies. Despite the small sample size, the beneficial effect of n-3 PUFA on platelet function, triglycerides and HDL-C is clearly highlighted.

Are Your Arteries Older Than Your Age?

PURPOSE

To determine the effect of age and atherosclerotic risk factors on the carotid intima-media layer thickness and morphology characteristics.

PATIENTS AND METHODS

Three groups of subjects were included in the study: Individuals with atherosclerotic risk factors including a family history of CHD, hypertension, hyperlipidemia, diabetes, and/or smoking (group A, n=180), age- and sex-matched healthy subjects without risk factors (group B, n=60) and a group of significantly younger volunteers (group C, n=25). The carotid artery was imaged longitudinally with B-mode ultrasound. Intima media thickness (IMT) was measured in the common (CCA) and internal carotid (ICA) arteries. Surface irregularity and continuity of the intima-media layer (IML) were assessed by high definition imaging. Echogenicity of the wall was quantified using Adobe Photoshop. The presence of calcium deposits was recorded. The double line wall pattern seen in young healthy people was used as a control to assess patterns and texture of the carotid IML. Fifteen subjects had their measurements repeated for intraobserver variability.

RESULTS

IMT measurements were reproducible in both the CCA and ICA (coefficient of variation 6% and 9%). IMT increased linearly with age (adjusted R(2)=0.72, p<0.0001), which was also an independent risk factor for increased IMT. All the risk factors had a significant association with increased IMT. In the lowest (third) decade the wall/blood interface was smooth and the double line was visualized with an echolucent center. With increased age and number of risk factors present, the wall/blood interface became more irregular (p<0.01), the double line was distorted (p<0.01) and the IML was more echogenic (p<0.01). The increase in IMT and the changes in the echogenicity of the IML were more pronounced in the ICA.

CONCLUSIONS

Age is an independent risk factor for increased IMT. Atherosclerotic risk factors are associated with the age-related changes seen in the IML. Such changes are also seen in younger asymptomatic volunteers with risk factors indicating that their arteries are older than their age.

Age-matched cavernous peak systolic velocity: a highly sensitive parameter in the diagnosis of arteriogenic erectile dysfunction

Recently it has been reported that there is a strict correlation between erectile dysfunction (ED) and cardiovascular diseases, but the importance of such relationship still needs to be addressed. Ultrasonographic peak systolic velocity (PSV), is considered a reliable parameter for the diagnosis of arteriogenic ED. However, the cut-off value of PSV<30 cm/s has sufficient sensitivity only in the diagnosis of advanced arteriogenic ED and it is not representative of peripheral vascular alterations. In the present study, we set up an age-adjustment of PSV - calculated with the formula PSV <6.73+age x 0.7 - that permits a more accurate diagnosis of vascular aetiology in ED patients and may predict the presence of carotid wall alterations. We studied 179 consecutive subjects (mean age 52 years, range 23-79 years), with a history of ED of at least 6 months, by means of penile colour doppler ultrasonography (P-CDU) and common carotid arteries colour doppler ultrasonography (CCA-CDU) between June 2003 and September 2004. Statistical analysis was carried out with the statistical software R. PSV and CCAD values showed a statistically significant negative correlation. Age adjustment further improved this relationship permitting to identify an age-dependent PSV cut-off given by the formula PSV <6.73+age x 0.7. The age-adjusted PSV cut-off allows an accurate interpretation of vascular aetiology in ED patients and predicts the presence of carotid wall alterations, from the intima-media pathologic thickness to the plaque formation, with high values of both sensitivity and specificity.

Associations between physical activity, peripheral atherosclerosis and bone status in healthy Japanese women

The aim of this cross-sectional study was to investigate whether physical activity and bone status may affect arterial thickening and stiffening in healthy Japanese women. Healthy women (n = 149; mean age, 54 years) were recruited from those who participated in a local health check program at the Osaka City University Hospital. Physical activity was assessed by physical functioning score of SF-36, and bone status by bone mineral density (BMD) in lumbar spine and calcaneus osteo-sono index (OSI). Arterial wall thickening assessed by intima-media thickness (IMT) in common carotid artery (CA) and femoral artery (FA), and arterial wall stiffening by peak wave velocity (PWV) in heart-carotid (hc) and heart-femoral (hf) as central segment and in heart-brachial (hb) and femoral-ankle (fa) as peripheral segment, respectively. By Spearman Rank correlation, lumbar spine BMD was correlated negatively with CA IMT (rho = -0.225, p < 0.05) and FA IMT (rho = -0.215, p < 0.05), and calcaneus OSI with FA IMT (rho = -0.330, p < 0.0001) but not CA IMT (rho = -0051, p = 0.5335). Both lumbar spine BMD and calcaneus OSI correlated negatively with PWV in all segments (all p < 0.05). Physical functioning score correlated weakly but significantly in a negative manner with all PWV segments (all p < 0.05) but not IMT. Multiple regression analyses revealed a significant association of calcaneus OSI (beta = -0.240, p = 0.0039) but not lumbar spine BMD (beta = -0.067, p = 0.4541) with FA IMT, although neither lumbar spine BMD nor calcaneus OSI was associated with CA IMT. Furthermore, physical functioning score was independently associated with hb and fa PWV but not hc and hf PWV, suggesting the preferential association with peripheral segment including lower extremities. Neither lumbar spine BMD nor calcaneus OSI was associated with any segment of PWV. In conclusion, it was suggested that calcaneus OSI might be associated with arterial wall thickening preferentially in femoral artery, and that physical activity may be associated with arterial wall stiffening in peripheral segment including lower extremity but not in central segment in healthy Japanese women.

The Effect of Pravastatin on Intima Media Thickness of the Carotid Artery in Patients with Normal Cholesterol

OBJECTIVE

Carotid intima media thickness (IMT) is a good indicator of the severity of atherosclerotic disease. Statins have been found to reduce carotid IMT in patients with hypercholesterolaemia. The aim of this study was to investigate if pravastatin is effective in reducing IMT in normocholesterolaemic patients with carotid artery disease.

METHODS

Patients with carotid artery stenosis and normal cholesterol levels who were not on a statin, were recruited. Patients were randomised to receive pravastatin or placebo daily. Serum concentration of cholesterol and IMT of common carotid arteries were measured before randomisation and at 3 monthly intervals thereafter, for 9 months. IMT was analysed to give the mean of a standardised 2 cm of the common carotid artery (CCA). Results are expressed as median (IQR) and comparison made using the Wilcoxon signed ranks test.

RESULTS

Fifty-four patients were examined. Twenty-eight patients were randomised to active treatment. There was no difference in demographic details and co-morbid states between the two groups. A significant reduction in cholesterol concentration was observed from 3 months in patients randomised to the pravastatin group [5.14(4.72-5.88) vs. 4.11(3.44-5.33), p < 0.05], while there was also a significant decrease in combined IMT form 6 months [1.53(1.36-1.87) vs. 1.41 (1.33-1.78), p < 0.05].

CONCLUSIONS

The results demonstrate that pravastatin reduces intima media thickness of the common carotid artery in normocholesterolaemic patients with moderate carotid stenosis.

Intima–media Thickness Score from Carotid and Femoral Arteries Predicts the Extent of Coronary Artery Disease

OBJECTIVES

In the present study we measured carotid and femoral intima-media thickness (IMT) by B-Mode ultrasonography, as well as angiographic extent and severity of coronary artery disease in patients referred for coronary arteriography, to assess the relation between individual IMT, scores incorporating IMT from the carotid and femoral arteries and the extent and severity of coronary artery disease.

METHODS

Two hundred and two patients referred for elective coronary angiography underwent ultrasound imaging of both carotid and femoral arteries for IMT measurements. An IMT score was developed as the number of sites with abnormal IMT (range 0-8). Multiple regression analysis indicated that IMT score was independently related to Gensini score, age and glucose levels. A high risk IMT score predicted an extended coronary artery disease although a low or medium risk IMT score cannot exclude the possibility of multivessel disease. Also, a high risk group could predict the performance of revascularization procedures and all cardiovascular events during a follow-up of 14.5 +/- 2.4 months.

CONCLUSIONS

IMT incorporating data from common and internal carotid artery, carotid bifurcation and femoral artery are well correlated with the extent of coronary atherosclerosis, much better than individual IMT. Patients with high IMT score usually have multivessel coronary artery disease and are at increased risk for subsequent cardiovascular events.

Glucose intolerance is associated with C-reactive protein and intima-media anatomy of the common carotid artery in patients with coronary heart disease

AIMS

The purpose of this study was to examine the relationship between glucose intolerance and levels of hsCRP, calculated intima-media area (cIMa) of the carotid artery and flow-mediated dilation of the brachial artery in 122 patients with a myocardial infarction 1-12 months before inclusion and without known diabetes mellitus.

METHODS

A standard oral glucose test (OGTT) was performed. Diabetes mellitus and impaired glucose tolerance (IGT) were defined according to the WHO criteria. Ultrasound measurement of cIMa of the carotid artery and flow-mediated dilation of the brachial artery were analyzed.

RESULTS

Patients with diabetes mellitus had higher hs-CRP compared with patients with IGT and those patients with normal glucose tolerance (P < 0.05). The greater cIMa of the carotid artery in those with diabetes mellitus compared with normal subjects failed to reach conventional levels of significance (P = 0.058). hs-CRP and cIMa were associated with plasma glucose 120 min after the glucose load (P < 0.05). A multiple stepwise regression analysis, including all variables significantly associated with plasma-glucose 120 min after glucose ingestion as independent variables, revealed an independent and significant association between plasma-glucose 120 min after glucose ingestion in the OGTT and CRP (P < 0.05). No association was observed between glucose intolerance and endothelial function.

CONCLUSION

Glucose intolerance was associated with hs-CRP and cIMa in patients with coronary heart disease without known diabetes mellitus. Thus, inflammation, atherosclerosis and impaired glucose tolerance are tightly interrelated disorders even in subjects without known diabetes mellitus.

Resumption of Spontaneous Erections in Selected Patients Affected by Erectile Dysfunction and Various Degrees of Carotid Wall Alteration: Role of Tadalafil

OBJECTIVE

To evaluate the possible improvement of sexual activity following a non on-demand administration of a long half-life selective inhibitor of phosphodiesterase type 5 (PDE-5) in elderly patients without major cardiovascular risk factors.

METHODS

Sixty subjects with erectile dysfunction (ED) aged 60-70 years and 30 control patients aged 18-40 years, affected by psychogenic ED, were studied. All underwent routine and hormonal blood tests, Nocturnal Penile Tumescence Rigidity Monitoring test (NPTRM), ultrasonographyc evaluation of common carotid artery intima-media thickness (IMT) and penile colour Doppler ultrasonography (P-CDU). All patients underwent therapy with tadalafil 20 mg in alternative days, non on-demand, at 5.00 p.m., for three consecutive months. IIEF-5, NPTRM test and P-CDU were re-evaluated one month after the end of the therapy.

RESULTS

Among elderly subjects 20 (33%) had normal carotid IMT (< 0.9 mm), 15 (25%) minimal increase of carotid thickness (IMT = 0.9-1.2 mm) and 25 (42%) one or more carotid plaques (IMT > 1.3 mm). NPTRM and P-CDU parameters were inversely related to different degrees of carotid wall alteration and showed a significant improvement respect to pre-treatment only in patients without atherosclerotic plaques. Also IIEF-5 showed significant improvements only in patients without atherosclerotic plaques.

CONCLUSIONS

In elderly subjects with slight or no signs of vascular disease at the carotid level, chronic and non on-demand treatment with tadalafil can induce spontaneous resumption of erections, probably through the improvement of endothelial function, but direct evidences to confirm this hypothesis are required.

Depressive symptoms and carotid artery intima-media thickness in young adults: the Cardiovascular Risk in Young Finns Study

OBJECTIVE

Depression and coronary heart disease are often comorbid conditions, but the mechanism behind this link is largely unknown. We tested the hypothesis that a high level of depressive symptoms in healthy young adults would be related to more prevalent preclinical atherosclerosis.

METHODS

We studied the association between depressive symptoms and carotid atherosclerosis in 1126 young adults (410 men and 716 women) as part of the ongoing population-based Cardiovascular Risk in Young Finns Study. The participants responded to a revised version of Beck's Depression Inventory in 1992, 1997, and 2001. Carotid atherosclerosis was assessed by measuring the thickness of the common carotid artery intima-media complex with ultrasound in 2001. Cardiovascular risk factors were measured in childhood/adolescence (1980) and in adulthood (2001).

RESULTS

In men, high scorers of depressive symptoms in 2001 had higher carotid artery intima-media thickness (0.63 mm) compared with those with low or moderate scores on depressive symptoms (0.57 mm). This relationship (B = 0.08, F[1, 405] = 9.24, p = .003) persisted after adjustment for age and cardiovascular risk factors in adolescence and adulthood. Depression scores in 1992 and 1997 were not predictive of intima-media thickness. In women, no association was found between depressive symptoms and intima-media thickness.

CONCLUSIONS

Depressive symptoms during early adulthood seem to be associated with higher levels of carotid intima-media thickness in men, but not in women.

Decrease of carotid intima-media thickness in patients at risk to cerebral ischemia after supplementation with folic acid, Vitamins B6 and B12

OBJECTIVE

Hyperhomocysteinemia is associated with atherosclerotic risk. Although vitamins can lower homocysteine (Hcy), information about effects on atherosclerosis is scarce.

METHODS

We used carotid intima-media thickness (IMT) as an accepted marker of atherosclerotic changes. Fifty patients (60 +/- 8 years) with IMT> or =1 mm were included. In a double blind, randomized trial they received daily 2.5 mg folic acid, 25 mg Vitamin B6, and 0.5mg Vitamin B12 or placebo for 1 year.

RESULTS

In the treatment group, Hcy decreased from 10.50 +/- 3.93 to 6.56 +/- 1.53 micromol/l (P < 0.0001), whereas it remained unchanged in the placebo group (10.76 +/- 2.36 versus 10.45+/-3.30 micromol/l). IMT decreased from 1.50 +/- 0.44 to 1.42 +/- 0.48 mm (P = 0.034) in the treatment group, whereas it increased from 1.47 +/- 0.57 to 1.54 +/- 0.71 mm in the placebo group. The mean individual changes of IMT between both groups differed significantly (-0.08 +/- 0.17 versus 0.07 +/- 0.25 mm, P = 0.019). Multiple regression analysis revealed that the observed effect on IMT depended only on medication.

CONCLUSIONS

Vitamin supplementation significantly reduces IMT in patients at risk. This effect is independent of Hcy concentration.

Carotid artery intimal medial thickness, brachial artery flow-mediated vasodilation and cardiovascular risk factors in diabetic and non-diabetic indigenous Australians

BACKGROUND

Indigenous Australians are at high risk for cardiovascular disease and type 2 diabetes. Carotid artery intimal medial thickness (CIMT) and brachial artery flow-mediated vasodilation (FMD) are ultrasound imaging based surrogate markers of cardiovascular risk. This study examines the relative contributions of traditional cardiovascular risk factors on CIMT and FMD in adult Indigenous Australians with and without type 2 diabetes mellitus.

METHOD

One hundred and nineteen Indigenous Australians were recruited. Physical and biochemical markers of cardiovascular risk, together with CIMT and FMD were measured for all subjects.

RESULTS

Fifty-three Indigenous Australians subjects (45%) had type 2 diabetes mellitus. There was a significantly greater mean CIMT in diabetic versus non-diabetic subjects (p=0.049). In the non-diabetic group with non-parametric analyses, there were significant correlations between CIMT and: age (r=0.64, p<0.001), systolic blood pressure (r=0.47, p<0.001) and non-smokers (r=-0.30, p=0.018). In the diabetic group, non-parametric analysis showed correlations between CIMT, age (r=0.36, p=0.009) and duration of diabetes (r=0.30, p=0.035) only. Adjusting for age, sex, smoking and history of cardiovascular disease, Hb(A1c) became the sole significant correlate of CIMT (r=0.35, p=0.01) in the diabetic group. In non-parametric analysis, age was the sole significant correlate of FMD (r=-0.31, p=0.013), and only in non-diabetic subjects. Linear regression analysis showed significant associations between CIMT and age (t=4.6, p<0.001), systolic blood pressure (t=2.6, p=0.010) and Hb(A1c) (t=2.6, p=0.012), smoking (t=2.1, p=0.04) and fasting LDL-cholesterol (t=2.1, p=0.04). There were no significant associations between FMD and examined cardiovascular risk factors with linear regression analysis

CONCLUSIONS

CIMT appears to be a useful surrogate marker of cardiovascular risk in this sample of Indigenous Australian subjects, correlating better than FMD with established cardiovascular risk factors. A lifestyle intervention programme may alleviate the burden of cardiovascular disease in Indigenous Australians by reducing central obesity, lowering blood pressure, correcting dyslipidaemia and improving glycaemic control. CIMT may prove to be a useful tool to assess efficacy of such an intervention programme.

[Cigarette smoking in military pilots and intima-media thickness of the carotid arteries]

BACKGROUND

It is well known that smoking is associated with an increase in arterial wall thickness. However, most studies of this problem have been undertaken in age and sex heterogenous groups, as well as in patients with already present other conventional risk factors. The aim of this study was to assess the effect of cigarette smoking on arterial wall thickness of the common carotid artery in asymptomatic pilots.

METHODS

The imaging of intima-media thickness of the posterior wall of the distal 1 cm of both common carotid arteries was performed using a B mode ultrasound device, in 39 pilots (37.05 +/- 6.66 years), for whom smoking was the single cardiovascular risk factor. Comparisons were made with 49 non-smokers (35.12 +/- 7.39 years).

RESULTS

The posterior walls of both common carotid arteries were thicker in smokers (left, p < 0.05; right, p > 0,05). Intima-media thickness was significantly lower on the right side than on the left side in both smokers and non-smokers (p < 0.01).

CONCLUSION

Cigarette smoking as the single cardiovascular risk factor was associated with the wall thickness of the carotid arteries in our study. This finding indicated that early atherosclerosis was already present in pilots-smokers entering middle age.

Cerebrovascular manifestations of Takayasu arteritis in Europe

OBJECTIVES

Takayasu arteritis is well known as a cause of stroke in Asia but has rarely been described in the Western world. Here we report the clinical and neuroimaging follow-up of a series of patients with Takayasu arteritis from Europe.

METHODS

Seventeen consecutive patients who fulfilled the diagnostic criteria for Takayasu arteritis of the American College of Rheumatology were evaluated on follow-up by standardized neurological examination, sonography and MRI.

RESULTS

At follow-up almost 20 yr after onset of symptoms, the subclavian artery and the common carotid artery were often affected. In addition, evidence of intracranial pathology was found in seven patients. In contrast to the severe vessel involvement, the neurological state was stable. Two patients had suffered from stroke before the diagnosis was made and therapy was initiated, and one patient had recurrent transient ischaemic attacks. Intermittent dizziness was associated with pathology of the vertebral and basilar arteries. However, clinical symptoms of subclavian steal syndrome were rare.

CONCLUSION

This case series shows that the clinical neurological course of Takayasu arteritis on treatment is benign in most cases despite the severe vascular involvement.

Long-term hormone replacement therapy delays the age related progression of carotid intima-media thickness in healthy postmenopausal women

OBJECTIVES

Carotid intima-media thickness (IMT) is an appropriate intermediate end point to investigate clinically relevant effects on atherogenesis. The study objective was to clarify whether long-term hormone replacement therapy (HRT) modifies the progress of age-related IMT in healthy postmenopausal Japanese women.

METHODS

One hundred and eighty-eight healthy postmenopausal women aged 42-69 years were recruited into the retrospective study. IMT was measured by B-mode real-time ultrasound in the following three groups of patients. One hundred and fifteen women who were prescribed estrogen plus progestin or estrogen alone were classified into two groups according to the HRT treated period: short-term (<2 years of treatment, n = 52) and long-term (> or =2 years, n = 63) HRT groups. The third group consisted an age-matched women (n = 73), who were never treated with HRT (non-HRT group) as a control.

RESULTS

Each group was divided into three subgroups according to age: < or =49 years, 50-59 years and 60 years or older. IMT in patients of age > or =60 years in the non-HRT group was 0.607 +/- 0.064 mm and was significantly higher compared with that in the other two age subgroups of non-HRT patients (< or =49 years: [0.495 +/- 0.051 mm; 50-59 years: 0.505 +/- 0.068 mm) (P < 0.05). In the short-term HRT group, IMT of > or =60-year-old-subjects (0.588 +/- 0.074 mm) was also significantly higher compared with that in the other two age subgroups (< or =49 years: 0.480 +/- 0.034 mm; 50-59 years: 0.511 +/- 0.062 mm). However, in the long-term HRT group, IMT was not significantly different among the three age subgroups. There was a significant relationship between IMT and age in non-HRT (r = 0.594, P < 0.0001) and short-term HRT (r = 0.542, P < 0.001) groups, but no significant relationship was observed in the long-term HRT (r = 0.195 , P = 0.1266) group.

CONCLUSIONS

In long-term HRT, more than 2 years may delay the age-related increase in IMT in healthy postmenopausal Japanese women.

Carotid intimal-media thickness as a surrogate for cardiovascular disease events in trials of HMG-CoA reductase inhibitors

Background

Surrogate measures for cardiovascular disease events have the potential to increase greatly the efficiency of clinical trials. A leading candidate for such a surrogate is the progression of intima-media thickness (IMT) of the carotid artery; much experience has been gained with this endpoint in trials of HMG-CoA reductase inhibitors (statins).

Methods and Results

We examine two separate systems of criteria that have been proposed to define surrogate endpoints, based on clinical and statistical arguments. We use published results and a formal meta-analysis to evaluate whether progression of carotid IMT meets these criteria for HMG-CoA reductase inhibitors (statins).

IMT meets clinical-based criteria to serve as a surrogate endpoint for cardiovascular events in statin trials, based on relative efficiency, linkage to endpoints, and congruency of effects. Results from a meta-analysis and post-trial follow-up from a single published study suggest that IMT meets established statistical criteria by accounting for intervention effects in regression models.

Conclusion

Carotid IMT progression meets accepted definitions of a surrogate for cardiovascular disease endpoints in statin trials. This does not, however, establish that it may serve universally as a surrogate marker in trials of other agents.

alpha-Glucosidase inhibitor reduces the progression of carotid intima-media thickness

OBJECTIVE

An open randomized prospective study was performed to elucidate the effect of an alpha-glucosidase inhibitor, voglibose, on the progression of atherosclerosis in subjects with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Voglibose at a dose of 0.4-0.6 mg/day was added on 51 subjects out of 101 type 2 diabetic patients being treated with diet, sulphonylurea (SU) or insulin injections, and the average (AveIMT) and maximum intima-media thickness (MaxIMT) of their carotid arteries were examined for 3 years.

RESULTS

Irrespective of the differences in treatments, addition of voglibose reduced the progression of AveIMT and MaxIMT to -0.024 +/- 0.047 (+/-S.D.) and -0.021 +/- 0.144 mm/year, respectively. Without voglibose, diabetic patients showed significant (P < 0.0001) progression of AveIMT and MaxIMT (0.056 +/- 0.046 and 0.098 +/- 0.122 mm/year, respectively). The administration of voglibose resulted in a significant reduction of hemoglobin A1c (HbA1c), total cholesterol and triglyceride concentrations, as well as an increase in HDL cholesterol concentration. Multivariate regression analysis showed that administration of voglibose independently reduced the progression of AveIMT by 0.069 mm/year (P < 0.0001).

CONCLUSIONS

These results suggest that voglibose reduces the progression of IMT and may be a candidate for an anti-atherosclerotic drug for type 2 diabetic patients.

Effects of amlodipine and lisinopril on intima-media thickness in previously untreated, elderly hypertensive patients (the ELVERA trial)

OBJECTIVE

To compare the effects of the calcium channel blocker amlodipine and the angiotensin-converting enzyme inhibitor lisinopril on intima-media thickness (IMT) in elderly, previously untreated hypertensive individuals.

DESIGN

A double-blind randomized parallel-group trial (the ELVERA trial).

PATIENTS

The study population comprised 166 newly diagnosed hypertensive individuals (aged 60-75 years) with diastolic blood pressure between 95 and 115 mmHg or systolic blood pressure between 160 and 220 mmHg, or both.

INTERVENTION

Patients were allocated randomly to groups to receive amlodipine 5-10 mg or lisinopril 10-20 mg for 2 years.

MAIN OUTCOME MEASURES

Before and after 1 and 2 years of treatment, IMT was measured in three carotid and two femoral arterial sites by B-mode ultrasound. The primary endpoint was the change from baseline of the combined mean maximum far wall IMT of carotid and femoral arteries, evaluated by repeated measurement analysis of the treatment effect in an intention-to-treat analysis.

RESULTS

After 2 years of treatment, amlodipine decreased IMT by 0.089 mm [95% confidence interval (CI) 0.144 to 0.037]. Lisinopril decreased IMT by 0.065 mm (95% CI 0.124 to 0.010). No differences between the two drugs were found (P = 0.18). Both treatment regimens achieved the greatest reduction of IMT after 1 year, with a slight increase after the second year, whereas the reduction in blood pressure was maintained. Comparing the carotid and femoral arteries, a significant treatment difference in the change from baseline in favour of amlodipine was observed in the IMT of the elastic common carotid artery (P < 0.05). The effects of the two drugs on the muscular common femoral artery were not different.

CONCLUSION

In a long-term study, amlodipine and lisinopril reduce IMT to a similar extent in newly diagnosed elderly hypertensive patients. It is suggested that the two drugs have different effects on arteries that are not prone to atherosclerosis.

Significance of intima-media thickness in femoral artery in the determination of calcaneus osteo-sono index but not of lumbar spine bone mass in healthy Japanese people

The aim of this cross-sectional study was to investigate whether physical activity and local arterial thickening may affect bone metabolism. To analyze the effects of physical activity and atherosclerosis on bone in healthy Japanese people, health-related quality of life (HRQL) and local arterial thickening were assessed by means of the Medical( )Outcomes Study 36-item Short Form (SF-36), and intimal-medial thickness (IMT) in common carotid artery (CA) and femoral artery (FA), respectively. Bone mineral density (BMD) in lumbar spine was measured by dual X-ray absorptiometry and the osteo-sono assessment index (OSI) of the calcaneus by ultrasound. Healthy subjects (106 male and 154 female) were recruited from those who participated in a local health check program at the Osaka City University Hospital. A significant correlation existed between lumbar spine BMD and calcaneus OSI (r=0.551, P<0.0001). Among various scores in SF-36, only physical functioning score correlated weakly but significantly in a positive manner with lumbar spine BMD (rho=0.156, P=0.0147) and calcaneus OSI (rho=0.190, P=0.0024). Lumbar spine BMD correlated negatively with FA IMT (rho=-0.191, P=0.0027) whereas calcaneus OSI with FA IMT (rho=-0.199, P=0.0014). Multiple regression analyses revealed a significant association between FA IMT and calcaneus OSI, whereas lumbar spine BMD did not correlate significantly with FA or CA IMT. When subjects were restricted to female, FA IMT, but not CA IMT, still showed tendency against independent factors negatively associated with calcaneus OSI. Furthermore, lumbar spine BMD, but not calcaneus OSI, was weakly but significantly associated with increased physical functioning score independently. In conclusion, it was suggested that physical activity may affect bone strength in lumbar spine and calcaneus and that FA IMT might be a significant determinant of bone strength in calcaneus, but not in lumbar spine, in healthy Japanese subjects.

Measurement of arterial wall thickness as a surrogate marker for atherosclerosis

Large observational studies and atherosclerosis regression trials of lipid-modifying pharmacotherapy have established that intima-media thickness of the carotid and femoral arteries, as measured noninvasively by B-mode ultrasound, is a valid surrogate marker for the progression of atherosclerotic disease. To exploit fully the potential of ultrasound imaging in atherosclerosis research, standardized and strictly implemented imaging protocols should be used in both observational studies and applied clinical research. This article describes such a protocol developed at the Academic Medical Center of the University of Amsterdam, the Netherlands. Results are presented from a study that estimated atherosclerosis progression from childhood into old age by measuring intima-media thickness in subjects with familial hypercholesterolemia compared with healthy controls.

Heparin cofactor II is a novel protective factor against carotid atherosclerosis in elderly individuals

BACKGROUND

Thrombin plays a crucial role in atherothrombotic changes. Because heparin cofactor II (HCII) inhibits thrombin actions after binding to dermatan sulfate at injured arterial walls, HCII may negatively regulate thrombin actions in vascular walls. We hypothesized that plasma HCII activity is a preventive factor against atherosclerotic changes, especially in elderly individuals who already have atherosclerotic vascular injuries.

METHODS AND RESULTS

Maximum plaque thickness (MPT) in the carotid artery was measured by ultrasonography in 306 Japanese elderly individuals (154 men and 152 women; age, 40 to 91 years; 68.9+/-11.1 years, mean+/-SD). The relevance of cardiovascular risk factors including plasma HCII activity to the severity of MPT was statistically evaluated. Plasma HCII activity decreased with age. Simple linear regression analysis after adjustments for age and sex showed that lipoprotein(a), glycosylated hemoglobin A1c, and presence of diabetes mellitus significantly contributed to an increase in MPT values (r=0.119, P<0.05; r=0.196, P<0.001; and r=0.227, P<0.0001, respectively). In contrast, high-density lipoprotein (HDL) cholesterol and HCII activity were negatively correlated with MPT values (r=-0.117, P<0.05, and r=-0.202, P<0.0005, respectively). Multiple regression analysis revealed that plasma HCII activity and HDL cholesterol independently contributed to the suppression of MPT values and that the antiatherogenic contribution of HCII activity was stronger than that of HDL cholesterol (P<0.001 and P<0.05, respectively).

CONCLUSIONS

These results suggest that HCII can be a novel and independent antiatherogenic factor. Moreover, HCII is a stronger predictive factor than HDL cholesterol against carotid atherosclerosis in elderly individuals.

Atherosclerosis measured by B-mode ultrasonography: effect of statin therapy on disease progression

Changes in intima-media thickness (IMT) and arterial lumen diameter-as measured by B-mode high-resolution ultrasonography and quantitative coronary angiography, respectively-are currently the only surrogate markers for progression of atherosclerotic disease recognized by regulatory authorities in the United States and Europe. Because atherosclerosis is a disease of the arterial wall, the ability of B-mode ultrasonography to provide visualization of IMT offers significant advantages over angiography. These advantages, as well as the safety and noninvasiveness of B-mode ultrasonography, have led to increasing use of this imaging technique in observational studies and interventional studies of lipid-lowering agents over the last decade. These observational studies clearly demonstrated an association between carotid IMT and atherosclerotic disease. Of the interventional studies, the recent Arterial Biology for the Investigation of the Treatment Effects of Reducing Cholesterol (ARBITER) trial found that use of atorvastatin 80 mg daily for aggressive lowering of plasma low-density lipoprotein cholesterol (LDL-C) concentrations to below current target levels was associated with significant IMT regression compared with results obtained with less aggressive plasma LDL-C lowering. A new study-Measuring Effects on Intima Media Thickness: an Evaluation of Rosuvastatin (METEOR)-will examine the effects of aggressive lipid-lowering treatment with rosuvastatin 40 mg daily on IMT. The cohort in this study will be individuals with mild hypercholesterolemia whose standard risk assessment does not categorize them as at sufficient risk of clinical disease to warrant initiation of lipid-lowering therapy despite their relatively high IMT values.

Using MRI to Assess Aortic Wall Thickness in the Multiethnic Study of Atherosclerosis: Distribution by Race, Sex, and Age

OBJECTIVE

Understanding the determinants of subclinical atherosclerosis may aid in elucidating the pathogenesis of atherosclerosis and guide prevention strategies. In this pilot study, we investigated the role of aortic wall thickness as a measure of subclinical atherosclerosis, assessed a method by which to measure aortic wall thickness using MRI, and attempted to define differences in aortic wall thickness by patient race, sex, and age. SUBJECTS AND METHODS. In this prospective study, 196 participants (99 black, 97 white; 98 men, 98 women) were selected from the Multiethnic Study of Atherosclerosis, which consists of participants 45-84 years old without clinical cardiovascular disease, who were recruited from six study centers in the United States. We performed fast spin-echo double inversion recovery MRI to measure thoracic aortic wall thickness. We tested interobserver agreement using the intraclass correlation coefficient, for sex and race differences in wall thickness using the Mann-Whitney test, and for associations between age and wall thickness using linear regression.

RESULTS

Reproducibility was excellent for measurements of average and maximal wall thickness on MRI. Average and maximal wall thickness increased with age (p < 0.001 and p = 0.002, respectively). Men had greater mean average wall thickness (2.32 vs 2.11 mm, p = 0.028) and mean maximal wall thickness (3.85 vs 3.31 mm, p = 0.010) than women. Blacks had greater mean maximal wall thickness than whites (3.74 vs 3.42 mm, p = 0.023).

CONCLUSION

MRI is a feasible method to measure aortic wall thickness with high interobserver agreement. Aortic wall thickness increases with age and also varies by race and sex.

Common carotid intima–media thickness is correlated with myocardial flow reserve in patients with coronary artery disease: a useful non-invasive indicator of coronary atherosclerosis

BACKGROUND

The common carotid intima-media thickness (IMT) is correlated with the angiographically determined coronary artery stenosis. However, their correlation is weak, which limits the clinical application of the IMT as a predictor of coronary artery stenosis. The IMT reflects diffuse early-phase atherosclerosis, whereas the angiographically determined coronary artery stenosis is a late-phase phenomenon. The latter is localized and rapidly progressive with plaque rupture and acute thrombosis. Instead of the angiographically determined coronary artery stenosis, we employed myocardial flow reserve (MFR) that reflects diffuse early-phase coronary atherosclerosis and impaired coronary vasodilatation function. We evaluated the relationship between the IMT and the MFR.

METHODS

Twenty-three patients with angiographically diagnosed coronary artery disease (CAD) underwent B-mode ultrasound examination to measure their common carotid IMT and positron emission tomography (PET) with dipyridamole intervention to obtain their MFR. We also performed B-mode ultrasound examination in 21 patients with hypertension without CAD and in 15 control subjects.

RESULTS

The common carotid IMT in patients with CAD was thickened (0.92+/-0.15 vs. 0.81+/-0.14 mm in patients with hypertension (P<0.05) and 0.69+/-0.13 mm in control subjects (P<0.01)). The IMT was inversely correlated with the MFR (r=0.51, P<0.01). The correlations between the MFR and most of the coronary risk factors (age, blood pressure, serum cholesterol level and triglyceride level, HbA1c level, smoking index) did not reach statistical significance.

CONCLUSIONS

Thickened common carotid IMT is also an indicator of reduced MFR or early-phase coronary atherosclerosis.

Prevalence of specific variant carotid geometric patterns and incidence of cardiovascular events in older persons

OBJECTIVES

We hypothesized that variant geometric patterns of the common carotid artery (CCA) predict the incidence of cardiovascular disease (CVD), after accounting for CCA intima-medial thickness (IMT).

BACKGROUND

Common carotid artery intima-media thickness has been associated with the incidence of cardiovascular disease.

METHOD

Noninvasive measurements of IMT were made with high-resolution ultrasonography in 5,640 subjects 65 years of age or older participating in the Cardiovascular Health Study. New coronary and/or cerebrovascular events served as outcome variables over a median 10.2-year follow-up. To characterize different carotid structural geometric patterns (CGP), vascular mass (VM) was combined with the wall-to-lumen ratio (W/L). Normal values for W/L and VM were defined as age-adjusted, gender-specific 75th percentiles of the 1,899 normotensive subjects free of CVD at baseline. Four CGPs were defined: CGP1 = normal W/L ratio and VM; CGP2 = arterial remodeling (i.e., increased W/L ratio with normal VM); CGP3 = arterial hypertrophy (i.e., increased W/L ratio with increased VM); and CGP4 = arterial hypertrophy with dilation (i.e., normal W/L ratio and increased VM).

RESULTS

Coronary or cerebrovascular events (adjusted for age, gender, traditional risk factors, and IMT) were associated with CGP in subjects free of CVD at baseline. Specifically, the hazard ratio (Cox proportional-hazards analyses) for CGP3 (arterial hypertrophy) was 1.25 (95% confidence interval [CI] 1.03 to 1.53), and for CGP4 (arterial hypertrophy with dilation) was 1.43 (95% CI 1.16 to 1.75) compared with CGP1 (normal).

CONCLUSIONS

Arterial hypertrophy defined by variant CGP patterns is associated with the development of new CVD, independent of age, traditional risk factors, and CCA IMT.

Relationship between vertebral bone marrow blood perfusion and common carotid intima-media thickness in aging adults

PURPOSE

To evaluate the relationship between vertebral marrow blood perfusion and common carotid intima-media thickness (IMT) in aging adults.

MATERIALS AND METHODS

An age- and sex-matched case control study was conducted. Subjects were contacted and enrolled voluntarily according to a database containing 2,258 cases that received carotid ultrasonography examination at our hospital in the previous two years. Forty-three pairs of subjects (56 male, 30 female; aged 44-85 years, average 63 years) underwent dynamic contrast-enhanced magnetic resonance (MR) study of the lumbar spine. The average peak enhancement percentage of the second to fourth lumbar vertebrae was used to represent the vertebral marrow perfusion status for each subject. The common carotid IMT, presence of plaque, peak enhancement percentage, body mass index (BMI), systolic and diastolic blood pressure, serum total cholesterol, high-density lipoprotein (HDL), and triglycerol levels were acquired for statistical analysis.

RESULTS

The average peak enhancement percentage was significantly lower in thickened IMT group compared to the normal IMT group (73 +/- 23 vs. 90 +/- 27, P=0.0023). The carotid IMT inversely correlated with vertebral peak enhancement percentage (r=-0.33, P=0.0018). The vertebral peak enhancement percentage was significantly lower in subjects with presence of any carotid plaque (P=0.032). Common carotid IMT was the only significant variable that was negatively associated with vertebral marrow perfusion after adjusting for the effect of sex, age, blood pressure, BMI, total cholesterol, HDL, and triglycerol level in linear regression model (P=0.008).

CONCLUSION

Our data demonstrate the negative association between vertebral marrow blood perfusion and common carotid IMT. These results suggest that common carotid IMT may provide the information of tissue perfusion status of the vertebral bone marrow.

Cardiovascular risk factors in childhood and carotid artery intima-media thickness in adulthood: the Cardiovascular Risk in Young Finns Study

CONTEXT

Exposure to cardiovascular risk factors during childhood and adolescence may be associated with the development of atherosclerosis later in life.

OBJECTIVE

To study the relationship between cardiovascular risk factors measured in childhood and adolescence and common carotid artery intima-media thickness (IMT), a marker of preclinical atherosclerosis, measured in adulthood.

DESIGN, SETTING, AND PARTICIPANTS

Population-based, prospective cohort study conducted at 5 centers in Finland among 2229 white adults aged 24 to 39 years who were examined in childhood and adolescence at ages 3 to 18 years in 1980 and reexamined 21 years later, between September 2001 and January 2002.

MAIN OUTCOME MEASURES

Association between cardiovascular risk variables (levels of low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], and triglycerides; LDL-C/HDL-C ratio; systolic and diastolic blood pressure; body mass index; smoking) measured in childhood and adulthood and common carotid artery IMT measured in adulthood.

RESULTS

In multivariable models adjusted for age and sex, IMT in adulthood was significantly associated with childhood LDL-C levels (P =.001), systolic blood pressure (P<.001), body mass index (P =.007), and smoking (P =.02), and with adult systolic blood pressure (P<.001), body mass index (P<.001), and smoking (P =.004). The number of risk factors measured in 12- to 18-year-old adolescents, including high levels (ie, extreme age- and sex-specific 80th percentile) of LDL-C, systolic blood pressure, body mass index, and cigarette smoking, were directly related to carotid IMT measured in young adults at ages 33 through 39 years (P<.001 for both men and women), and remained significant after adjustment for contemporaneous risk variables. The number of risk factors measured at ages 3 to 9 years demonstrated a weak direct relationship with carotid IMT at ages 24 to 30 years in men (P =.02) but not in women (P =.63).

CONCLUSIONS

Risk factor profile assessed in 12- to 18-year-old adolescents predicts adult common carotid artery IMT independently of contemporaneous risk factors. These findings suggest that exposure to cardiovascular risk factors early in life may induce changes in arteries that contribute to the development of atherosclerosis.

Risk factors for asymptomatic atherosclerosis in Japanese type 2 diabetic patients without diabetic microvascular complications

Atherosclerotic vascular diseases are frequently associated with diabetes mellitus. There has been increasing evidence showing that the atherosclerotic diseases in diabetic patients are distinct from diabetic microvascular complications as to their pathophysiology and epidemiology. However, we have no information on the prevalence of asymptomatic atherosclerosis in diabetic patients before the onset of microvascular diseases. In the present investigation, we aimed to evaluate risk factors for the atherosclerosis in type 2 diabetic patients without the microvascular diseases. For this purpose, we evaluated atherosclerotic change of carotid arteries in 125 Japanese type 2 diabetic patients who had neither atherosclerotic vascular diseases nor diabetic microvascular complications. When atherosclerotic change was defined as the mean intima-media thickness (IMT) of >/= 1.1 mm and/or the presence of plaque lesion, 50% of patients had atherosclerosis of the carotid arteries. Risk factors for the carotid atherosclerosis were age, low-density lipoprotein (LDL)-cholesterol, hypertension, and diabetes treatment. Age and LDL-cholesterol were associated with mean IMT. Age, diabetes treatment, LDL-cholesterol, and hypertension were positively associated with plaque lesion, while high-density lipoprotein (HDL)-cholesterol was negatively associated with it. Fasting plasma glucose, glycosylated hemoglobin (HbA(1c)), and known diabetes duration remained unassociated with any parameters of asymptomatic atherosclerosis of the carotid arteries. These results indicate that glycemic control is unrelated with asymptomatic atherosclerosis in type 2 diabetic patients without diabetic microvascular complications. Conventional risk factors and diabetes treatment are independently associated with atherosclerosis of the carotid arteries in these patients.

Clinical implications of carotid artery remodeling in acute coronary syndrome

OBJECTIVES

We investigated the relationship between ultrasonographic features of the carotid artery and the angiographic features of coronary plaques in acute coronary syndrome (ACS).

BACKGROUND

The carotid intima-media thickness (IMT) may be a marker of advanced coronary artery disease.

METHODS

Consecutive ACS patients (N = 125) underwent B-mode ultrasonography within one week of the acute coronary event. Using a 7.5-MHz linear array transducer, the common carotid IMT, interadventitial diameter, and luminal diameter were examined. Carotid plaques were also assessed. Then patients were divided into two groups based on the number of complex plaques identified by coronary angiography.

RESULTS

The carotid IMT of 75 patients with multiple complex coronary plaques was significantly larger than that of 50 patients with solitary plaques (p < 0.0003). The prevalence of soft and hard carotid plaques was higher in the group with multiple coronary plaques than in those with single plaques (28% vs. 12%, p < 0.04 and 13% vs. 0%, p < 0.008, respectively). Additionally, the carotid interadventitial diameter was larger in the patients with multiple plaques than in those with single plaques (7.93 +/- 0.97 mm vs. 7.48 +/- 0.88 mm, p < 0.01), and a significant correlation was observed between the carotid IMT and interadventitial diameter (R = 0.54, p < 0.0001).

CONCLUSIONS

In ACS, multiple complex coronary plaques are associated with positive carotid remodeling, suggesting that plaque vulnerability may be a systemic phenomenon.

Implication of earlier carotid atherosclerosis for stroke and its subtypes

In addition to advanced stenosis, earlier stages of carotid atherosclerosis are associated with the risk for stroke. Based on a recent report, this review will focus on the associations between carotid atherosclerosis and stroke subtypes. The authors report increased severity of carotid atherosclerosis in atherothrombotic and lacunar infarction patients, compared to nonstroke patients. However, the severity was similar between nonstroke patients and those with cardioembolic infarction and cerebral hemorrhage. By receiver operating characteristic curve analyses, although evaluation of carotid atherosclerosis appears to help for risk assessment of atherothrombotic and lacunar infarction, the potential for benefit may be greater for atherothrombotic. Large prospective studies are still necessary to establish the link between earlier carotid atherosclerosis and the future risk for specific stroke subtypes.

Noninvasive ultrasound measurements of aortic intima-media thickness: implications for in vivo study of aortic wall stress

OBJECT

The abdominal aorta (AA) has a predilection for aneurysm formation. An etiologic factor may be underlying aortic wall stress. The purpose of this study was to examine whether the intima-media thickness (IMT) of the AA, as a surrogate to arterial wall thickness, can be measured noninvasively with satisfactory results to calculate circumferential wall stress, and to evaluate regional and gender differences in wall stress.

METHODS

Sixty-five middle-aged healthy subjects were examined with B-mode ultrasound to determine the diameter and IMT in the infrarenal AA, common carotid artery (CCA), common femoral artery (CFA), and popliteal artery (PA). Blood pressure was measured noninvasively in the brachial artery. Wall stress was calculated according to the law of LaPlace.

RESULTS

Intraobserver variability for the IMT in the AA showed a coefficient of variation of 11%. IMT was thickest in the AA compared with the CCA, CFA, and PA (P <.001). There was a gender difference in IMT in the CFA (P <.05) and PA (P <.01) but not in the AA. Greater wall stress was found in the AA than in the CCA (P <.001) and PA (P <.001), with men having greater wall stress in all studied arterial regions.

CONCLUSIONS

Aortic IMT can be satisfactorily studied in vivo with noninvasive B-mode ultrasound. There are gender differences in IMT and wall stress, and the largest wall stress is found in the AA in men, which might be important in aneurysm development.

Early vascular damage in primary hypoalphalipoproteinemia

The relationship between hypoalphalipoproteinemia (hypoalpha), a metabolic disorder characterized by reduced high-density lipoprotein (HDL) cholesterol levels, and atherosclerotic disease is not completely understood. We investigated arterial functional and structural changes in 19 subjects with hypoalpha (HDL cholesterol < or = 0.7 mmol/L for men and < or = 0.8 mmol/L for women; 13 men; 47 +/- 7 years) and in 21 healthy control subjects (11 men; 46 +/- 13 years). Brachial-artery flow-mediated vasodilation (FMV) and intima-media thickness (IMT) of the carotid and femoral arteries were determined in all subjects. FMV was significantly lower in hypoalpha than in controls (5.6% +/- 4.3% v 8.2% +/- 2.7%; P <.05). IMT was greater in hypoalpha than in controls at both the internal carotid (0.83 +/- 0.1 mm v 0.69 +/- 0.1 mm) and superficial femoral level (0.83 +/- 0.2 mm v 0.68 +/- 0.1 mm; both P <.05). FMV had a positive correlation with HDL cholesterol (r =.42, P =.06) and a negative one with triglycerides (r = -0.38, P =.01). An inverse relationship was found between HDL cholesterol and internal carotid and superficial femoral IMT (r = -0.64 and r = -0.60, respectively; P <.01 for both) and a positive one between triglycerides and internal carotid and superficial femoral IMT (r =.53 and r =.47, P <.05). In a multivariate regression analysis, brachial FMV was predicted by HDL cholesterol and brachial diameter (beta =.42 and -0.43, respectively; both P <.05). HDL cholesterol was the only significant predictor of internal carotid and superficial femoral IMT (beta = -0.45 and -0.49, respectively; both P <.05). In conclusion, subjects with primary hypoalpha, without overt cardiovascular disease, are characterized by an impaired endothelial function and by an increase in large-artery IMT.

Effect of tibolone treatment on intima-media thickness and the resistive indices of the carotid arteries

OBJECTIVE

To assess the effect of tibolone treatment on the intima-media thickness (IMT) of the common carotid artery (CCA) and the resistive indices (RIs) of the CCA and internal (ICA) and external (ECA) carotid and the vertebral arteries (VAs) in postmenopausal women as sonographic markers of atherosclerosis.

DESIGN

A prospective study.

SETTING

University hospital.

PATIENT(S)

Twenty postmenopausal women who had no cardiovascular disease.

INTERVENTION(S)

Noninvasive measurements of the IMT of the CCA and the RI of the CCA, ICA, ECA, and VA were made with ultrasound at baseline and after 12 weeks of tibolone treatment.

MAIN OUTCOME MEASURE(S)

IMT of the CCA and RI of the CCA, ICA, ECA, and VA.

RESULT(S)

Three months of tibolone treatment decreased the IMT of the CCA (mean +/- SD) from 0.70 +/- 0.22 mm (95% confidence interval [CI], 0.60-0.80) to 0.47 +/- 0.17 mm (95% CI, 0.39-0.55) by 28%. Resistive indices of the CCA, ICA, and VA also decreased significantly.

CONCLUSION(S)

The present study showed that tibolone treatment decreases both the IMT of the CCA and RI of the CCA, ICA, and VA, which appears to be related to its anti-atherosclerotic effect. Nevertheless, the clinical implications of these findings are yet to be investigated.

Hypertension and changes of cognitive function in 81-year-old men: a 13-year follow-up of the population study "Men born in 1914", Sweden

BACKGROUND

The relationship between blood pressure levels and decline of cognition has been discussed previously, but little is known about the confounding effect of lifestyle factors, antihypertensive treatment and disease in the elderly.

OBJECTIVE

To examine the association between systolic (SBP) and diastolic (DBP) blood pressure, changes of DBP and SBP and hypertension (HT) on cognitive function, while controlling for confounding factors.

DESIGN

A longitudinal cohort study of men born in 1914 and residing in the municipality of Malmö studied at age 68 and 81 years.

SETTING

Probands invited to a university clinic.

SUBJECTS

One hundred and eighty-six out of 281 invited men still alive in 1995/6 participated in the most recent follow-up.

MAIN OUTCOME

Change of the cognitive performance in the verbal (Paired Associates and Synonyms), spatial (Block Design and Benton Visual Retention test) and speed (Digit Symbol Substitution) functions.

RESULTS

DBP by tertiles at 68 years, but not HT, was inversely related to verbal, spatial and speed performance at 81 years. Only spatial function was related to SBP at 68 years. The association between DBP and SBP by tertiles, and spatial functions (Block Design and Benton Visual Retention test) remained after controlling for education, marital status, smoking, alcohol and physical activity, and intermediates such as arteriosclerotic manifestations (block design, beta = 0.17; = 0.029) in multiple regression models. A decrease in DBP was likewise related to spatial (beta = 0.16; = 0.049) and speed performance (beta = 0.17; = 0.039) in the same regression model.

CONCLUSIONS

Evidence is found to support the hypothesis that hypertension, especially high DBP in late midlife, is associated with a decline in spatial performance of cognitive functions in elderly men.

Westernization of lifestyle markedly increases carotid intima-media wall thickness (IMT) in Japanese people

To illustrate the impact of westernization of lifestyle on the development of pre-clinical atherosclerosis in Japanese people, we compared risk factors for atherosclerosis such as serum lipids, blood pressure, BMI, insulin resistance, and smoking habits between non-diabetic native Japanese and non-diabetic Japanese Americans. Two hundred and twenty two non-diabetic Japanese Americans living in Hawaii and 271 non-diabetic Japanese living in Hiroshima, Japan were studied. Carotid intima-media wall thickness (IMT) was measured in all subjects by one physician. For all measurements the same ultrasound instrumentation was used. Although no significant differences were seen in serum total cholesterol (TC), triglycerides, or LDL-cholesterol (LDL-C) levels between the two groups in the 1998 study, previous to 1998 these three parameters were significantly higher in Japanese Americans than native Japanese in our study which has spanned the past 20 years. IMT was significantly greater in Japanese Americans than native Japanese (1.20+/-0.03 mm vs. 0.98+/-0.03 mm, (mean+/-S.E.) respectively; P<0.0001). Moreover Japanese Americans reach an IMT of 1.1 mm at age 50, whereas the native Japanese reach this value at age 70. These observations indicate more rapid atherosclerosis progression in Japanese Americans. Based on our IMT measurements, the status and the estimated progression of atherosclerosis in Japanese Americans is increased. Since IMT is a validated endpoint for assessment of atherosclerotic disease risk, it can be concluded that Japanese Americans are at increased risk for cardiovascular disease.

Measurement of subclinical atherosclerosis: beyond risk factor assessment

PURPOSE OF REVIEW

Assessment of subclinical atherosclerosis using the current available noninvasive imaging modalities holds promise for individual cardiovascular risk management and monitoring efficacy of therapeutic interventions (i.e. surrogate end-points). The present review addresses benefits and limitations of flow-mediated dilatation, intima-media thickness, electron-beam computed tomography and magnetic resonance coronary angiography.

RECENT FINDINGS

Both carotid intima-media thickness and peripheral flow-mediated dilatation correlate inversely with cardiovascular risk factors and coronary artery disease. They have been shown to carry predictive value for future cardiovascular events, but clinical application of both intima-media thickness and flow-mediated dilatation demands further methodological maturation of these techniques. Intima thickening has been successfully targeted in numerous intervention trials, but determination of an explicit threshold value beyond which cardiovascular risk significantly increases will facilitate its utility as a routine clinical tool. Electron-beam computed tomography can accurately detect and quantify coronary artery calcification (an established marker of the total coronary plaque burden). However, lack of evidence of its additional predictive power for future coronary events warrants for further research. Finally, magnetic resonance coronary angiography appears to be a promising technique, integrating both functional and anatomical aspects of coronary artery disease. Properly designed studies are needed to determine its value in clinical practice.

SUMMARY

Various noninvasive imaging techniques have recently emerged that may find applications in clinical research. However, before widespread clinical utilization, further technical refinement of all of the cited imaging modalities is mandatory. It will be a challenge over the coming few years to clarify whether improvements in surrogate end-points can directly be translated into improved outcomes.

Efficacy and safety of statin therapy in children with familial hypercholesterolemia: a randomized, double-blind, placebo-controlled trial with simvastatin

BACKGROUND

A multicenter, randomized, double-blind, placebo-controlled study was conducted to evaluate LDL cholesterol-lowering efficacy, overall safety, and tolerability and the influence on growth and pubertal development of simvastatin in a large cohort of boys and girls with heterozygous familial hypercholesterolemia (heFH).

METHODS AND RESULTS

A total of 173 heFH children (98 boys and 75 girls) were included in this study. After a 4-week diet/placebo run-in period, children with heFH were randomized to either simvastatin or placebo in a ratio of 3:2. Simvastatin was started at 10 mg/d and titrated at 8-week intervals to 20 and then 40 mg/d. During a 24-week extension period, the patients continued to receive simvastatin (40 mg) or placebo according to their assignment. After 48 weeks of simvastatin therapy, there were significant reductions of LDL cholesterol (-41%), total cholesterol (-31%), apolipoprotein B (-34%), VLDL cholesterol (-21%), and triglyceride (-9%) levels. HDL cholesterol and apolipoprotein A-I levels were increased by 3.3% and 10.4%, respectively (not significant). No safety issues became evident. Except for small decreases in dehydroepiandrosterone sulfate compared with placebo, there were no significant changes from baseline in adrenal, gonadal, and pituitary hormones in either treatment group.

CONCLUSIONS

Simvastatin significantly reduced LDL cholesterol, total cholesterol, triglyceride, VLDL cholesterol, and apolipoprotein B levels and was well tolerated in children with heFH. There was no evidence of any adverse effect of simvastatin on growth and pubertal development. Therefore, simvastatin at doses up to 40 mg is a well-tolerated and effective therapy for heFH children.

Chlamydia pneumoniae seropositivity and early carotid atherosclerosis in a suburban Japanese population

To evaluate the association between Chlamydia pneumoniae (C. pneumoniae) infection and carotid atherosclerosis (CA), we investigated CA assessed by carotid B-mode ultrasound and known or suspected atherosclerotic risk factors including C. pneumoniae IgG and IgA antibodies in 2410 residents (mean age 54.5+/-13.6 years, 697 men) of a suburban Japanese town. CA was found in 30.1% of men and in 14.0% of women, IgG in 59.4% and in 51.4%, and IgA in 36.9% and in 32.4%, respectively. In univariate analysis, most conventional atherosclerotic risk factors and IgA antibody were significantly associated with CA in both sexes, but not IgG. In multivariate logistic regression analysis, independent risk factors for CA were confirmed with age and triglycerides (TG) in men and age, systolic blood pressure, pack-years of smoking, and low-density lipoprotein cholesterol (LDL-C) in women, but not IgG and IgA in either sex. These results do not support C. pneumoniae infection as an important risk factor for CA in this Japanese population.

The carotid artery as a noninvasive window for cardiovascular risk in apparently healthy individuals

Cardiovascular diseases are the leading cause of death and disability in industrialized countries. Because the etiologies are related to alteration of arterial wall properties, the noninvasive evaluation could help the presymptomatic diagnosis and potentially the prevention of future events. Ultrasound (US) is currently the only modality to image the arterial wall in real-time with sufficient resolution to allow for observation of its morphological, hemodynamic and elastic properties. Increased wall thickness and atheromatous plaques of carotid arteries are associated with cardiovascular risk factors and diseases. Also, carotid Doppler waveforms and wall elasticity may have associations with arterial health. Although evaluation of these arterial properties are currently limited to the research laboratories, most of such properties can be evaluated in the standard setting of carotid ultrasonography. This article reviews "potential" utilities of carotid US evaluation for cardiovascular risk assessment in apparently healthy individuals.

Arterial wall thickness and the risk of recurrent ischemic events in carriers of the prothrombin G20210A mutation with clinical manifestations of atherosclerosis

The G20210A mutation in the prothrombin gene is an established risk factor for venous thrombosis. There is controversy about the role of this mutation in arterial thrombotic disease and atherosclerosis. We determined the presence of the prothrombin mutation and examined its influence on carotid and femoral artery intima-media thickness (IMT) and the occurrence of new ischemic events during follow-up in 277 patients with clinically manifest atherosclerotic disease: ischemic stroke, myocardial infarction or peripheral arterial disease. The mean age at entry was 63 years. Mean IMT was significantly higher in carriers of the prothrombin mutation (1.17 (SD 0.29) mm versus 0.97 (SD 0.25) mm: (delta)IMT=0.20, P=0.02). The increase in IMT was not attributable to differences in age, type of arterial disease or cardiovascular risk factors between carriers and non-carriers. During a mean follow-up of 3.5 years, a strong trend for more ischemic events was observed: 4 of the 11 carriers suffered from a recurrent ischemic event, compared with 30 of the 164 male non-carriers (36 versus 18%; P=0.06). These results suggest that the G20210A mutation contributes to the process of arterial wall thickening and is associated with the occurrence of ischemic events in a cohort of elderly persons with established atherosclerosis.

Increased thickness of the arterial intima-media detected by ultrasonography in patients with rheumatoid arthritis

OBJECTIVE

To determine whether arterial wall thickening is advanced in rheumatoid arthritis (RA) patients compared with healthy controls by measuring the intima-media thickness (IMT) of the common carotid and femoral arteries, and to evaluate the factors associated with arterial IMT in patients with RA.

METHODS

We studied 138 RA patients and 94 healthy controls (matched for age, sex, and other major risk factors for atherosclerosis). IMT was measured on digitized still images of the common carotid and femoral arteries obtained by high-resolution ultrasonography (10-MHz in-line Sectascanner). Laboratory variables relevant to RA activity were measured by routine methods. The degree of RA progression was assessed by scoring (Larsen method) metacarpophalangeal (MCP) joints on hand radiographs. Activities of daily living were determined by a modified Health Assessment Questionnaire (M-HAQ) score, and physical activity levels were assessed by ultrasound measurement of the calcaneus (expressed as the osteo-sono assessment index [OSI] Z score).

RESULTS

Common carotid and femoral artery IMTs were significantly higher (P < 0.05) in RA patients (mean +/- SD 0.641 +/- 0.127 and 0.632 +/- 0.125 mm, respectively) compared with controls (0.576 +/- 0.115 and 0.593 +/- 0.141 mm, respectively). Multiple regression analysis revealed a significant association between RA and the common carotid artery IMT. Moreover, the common carotid artery IMT in RA patients was positively associated with disease duration, the MCP joint Larsen score, and the M-HAQ score, and was negatively associated with the calcaneus OSI Z score. No significant association was found between corticosteroid treatment and common carotid artery IMT.

CONCLUSION

RA patients exhibited greater thickness of the common carotid and femoral arteries than healthy controls. The duration and severity of RA and decreased activities of daily living, but not corticosteroid treatment, were independently associated with the increased arterial wall thickness.

Serum cholesterol affects blood pressure regulation

A close relationship between abnormalities of the lipid metabolism and arterial hypertension has been observed in several epidemiological studies. The aim of the present study was to investigate whether serum cholesterol might affect blood pressure (BP) levels at rest, during ambulatory monitoring or during sympathetic stimulation-independently of other variables such as body weight or serum insulin-thus influencing the outcome of hypertensive complications. Seventy-three patients with sustained newly-discovered and never-treated hypertension were divided into tertiles according to their serum cholesterol levels and their resting BP, 24-h BP and BP during isometric exercise (handgrip) were compared. Cardiac mass and carotid wall thickness were measured by echographic technique. The results were that tertiles were similar for body weight, blood glucose and serum insulin, but different for serum cholesterol and triglycerides. BP at rest and during 24-h monitoring was similar in the three groups, whilst a significant difference was detected during sympathetic stimulation by handgrip, with systolic and diastolic BP increasing by 16/12, 28/19 and 30/23 mm Hg (P < 0.01) in lower, medium and higher tertiles, respectively. Intima-media layer of the carotid arteries was also significantly thickened in the groups with higher cholesterol levels (0.54 +/- 0.07, 0.67 +/- 0.14, 0.68 +/- 0.15, P < 0.05). These data support the conclusion that even in patients with recently discovered hypertension, cholesterol levels may influence the BP response to adrenergic stimulation as well as the outcome of target organ disease.

Carotid intima media thickness decreases after pancreas transplantation

BACKGROUND

Pancreas transplantation (PTX) improves diabetic microvascular complications, but it is unknown whether PTX alters macrovascular disease. Carotid intima media thickness (IMT) has been shown to correlate with cardiovascular events, so this study was designed to evaluate changes in carotid IMT after PTX.

METHODS

Four groups were studied: PTX candidates (n=60); successful PTX recipients (n=89; mean time since PTX=4.0+/-0.3 years); patients with type 1 diabetes but without nephropathy (n=20); and normal controls (n=32). Mean IMT and mean of maximum carotid IMT measurements (mean-max IMT), hemoglobin A1C, serum creatinine, body mass index (BMI), blood pressure, smoking status, use of hypolipidemic medications, and fasting lipids were determined in all groups.

RESULTS

Age, gender distribution, and BMI were not different among the groups. Duration of diabetes was also equal between pre- and post-PTX groups. Mean and mean-max IMT were greatest pre-PTX and decreased after PTX (P<0.05) to a value that was not different from controls. Hemoglobin A1C and creatinine decreased, and high density lipoprotein (HDL) increased after PTX (P<0.05), but there were no significant differences in other lipids, BMI, use of lipid lowering agents, blood pressure, or smoking status.

CONCLUSIONS

Carotid IMT is lower after PTX, suggesting a reduction in overall cardiovascular risk independent of changes in use of hypolipidemic agents, smoking, blood pressure, BMI, or lipids, except HDL. Improved carotid IMT after successful PTX predicts a reduction in future vascular disease events and suggests that the macrovascular disease of type 1 diabetes is at least partially reversible with improved glucose control.