Extracranial carotid artery stenosis: prevalence and associated risk factors in elderly stroke patients

Derivation of a clinical prediction score for the diagnosis of clinically significant symptomatic carotid artery disease

OBJECTIVES

Emergent vascular imaging identifies a subset of patients requiring immediate specialized care (i.e. carotid stenosis > 50%, dissection or free-floating thrombus). However, most TIA patients do not have these findings, so it is inefficient to image all TIA patients in crowded emergency departments (ED). Our objectives were to derive and internally validate a clinical prediction score for clinically significant carotid artery disease in TIA patients.

METHODS

This was a planned secondary analysis of a prospective cohort study from 14 Canadian EDs. Among 11555 consecutive adult ED patients with TIA/minor stroke symptoms over 12 years, 9882 had vascular imaging and were included in the analysis. Our main outcome was clinically significant carotid artery disease, defined as extracranial internal carotid stenosis ≥ 50%, dissection, or thrombus in the internal carotid artery, with contralateral symptoms.

RESULTS

Of 9882 patients, 888 (9.0%) had clinically significant carotid artery disease. Logistic regression was used to derive a 13-variable reduced model. We simplified the model into a score (Symcard [Symptomatic carotid artery disease] Score), with suggested cut-points for high, medium, and low-risk stratification. A substantial portion (38%) of patients were classified as low-risk, 33.8% as medium risk, and 28.2% as high risk. At the low-risk cut-point, sensitivity was 92.9%, specificity 41.1%, and diagnostic yield 1.7%.

CONCLUSIONS

This simple score can predict carotid artery disease in TIA patients using readily available information. It identifies low-risk patients who can defer vascular imaging to an outpatient or specialty clinic setting. Medium-risk patients may undergo imaging immediately or with slight delay, depending on local resources. High-risk patients should undergo urgent vascular imaging.

Optimal medical therapy is lacking in patients undergoing intervention for symptomatic carotid artery stenosis and protects against larger areas of cerebral infarction

OBJECTIVES

Carotid interventions are indicated for both patients with symptomatic and a subset of patients with severe asymptomatic carotid artery stenosis (CAS). Symptomatic CAS accounts for up to 12%-25% of overall carotid interventions, but predictors of symptomatic presentation remain poorly defined. The aim of this study was to identify factors associated with symptomatic CAS in our patient population.

METHODS

Between January 2015 and February 2022, an institutional retrospective cohort study of prospectively collected data on patients undergoing interventions for CAS was performed. Procedures included carotid endarterectomy (CEA), transcarotid artery revascularization (TCAR), and transfemoral carotid artery stenting (TF-CAS). Demographic data, comorbidities, procedural details, and anatomic features from various imaging modalities were collected. Comparisons were made between symptomatic (symptoms within the prior 6 months) and asymptomatic patients.

RESULTS

During the study period, 279 patients who underwent intervention for symptomatic CAS were paired with a randomly selected cohort of 300 patients who underwent intervention for asymptomatic CAS from a total patient cohort of 1143 patients undergoing interventions for asymptomatic CAS. Demographic data did not differ between groups. Patients with symptomatic CAS more frequently had prior TIA/stroke (>6 months remote to the current event), but less frequently had coronary artery disease or chronic kidney disease and were less likely to receive adequate medical management including antihypertensive agents, lipid-lowering agents, and anti-platelet therapy. On multivariate analysis, remote prior TIA/stroke and lack of anti-platelet therapy remained significant. Among symptomatic patients presenting with stroke, lack of anti-platelet therapy was associated with an overall larger area of parenchymal involvement. No difference was observed with single versus dual anti-platelet therapy. Furthermore, symptomatic patients were more likely to have ulcerated plaques (30.9% vs 18%, p < .001), and symptomatic patients with ulcerated plaques more frequently had less than 50% compared to moderate/severe CAS. Nine patients who presented with symptoms had mild CAS and underwent intervention.

CONCLUSIONS

Symptomatic CAS was associated with a history of remote prior symptoms and lack of anti-platelet therapy at time of presentation. Furthermore, symptomatic patients not on anti-platelet agents were more likely to have a greater area of parenchymal involvement when presenting with stroke and symptomatic patients with ulcerated plaques were more likely to have mild CAS, suggesting the role of plaque instability in symptomatic presentation. These findings underscore the importance of appropriate medical management and adherence in all patients with CAS and perhaps a role for more frequent surveillance in those with potentially unstable plaque morphology.

Prevalence and risk factors of symptomatic carotid stenosis in patients with recent transient ischaemic attack or ischaemic stroke in the Netherlands

INTRODUCTION

Literature on prevalence of symptomatic internal carotid artery stenosis is scarce and heterogeneous. Prevalence may have decreased in recent years due to improved management of cardiovascular risk factors. We aim to estimate current prevalence and identify risk factors of ipsilateral internal carotid artery stenosis in patients with recent hemispheric transient ischaemic attack or ischaemic stroke in the Netherlands.

PATIENTS AND METHODS

We included consecutive adult patients admitted to two large hospitals in the Netherlands in 2014 who suffered from amaurosis fugax, retinal ischaemia, transient ischaemic attack or ischaemic stroke in the vessel territory of the internal carotid artery. Primary outcome was presence of ipsilateral internal carotid artery stenosis (degree subdivided following NASCET criteria), as assessed with duplex ultrasonography, computed tomography angiography and/or magnetic resonance angiography. We used univariable and multivariable logistic regression to identify risk factors for the presence of a 50-100% internal carotid artery stenosis.

RESULTS

We analysed 883 consecutive patients with recent transient ischaemic attack or ischaemic stroke. Of these, 110 (12.5%) had 50-99% ipsilateral internal carotid artery stenosis. Subgroup analyses showed higher prevalence of any degree of internal carotid artery stenosis for male sex and White patients. In adjusted analyses, higher age (odds ratio 1.4/10 years; 95% confidence interval 1.16-1.63), male sex (odds ratio 2.8; 95% confidence interval 1.83-4.19), retinal ischaemia (odds ratio 2.5; 95% confidence interval 1.32-4.76) and current smoking (odds ratio 1.8; 95% confidence interval 1.09-2.79) were statistically significant risk factors for 50-100% internal carotid artery stenosis.

CONCLUSION

The prevalence of internal carotid artery stenosis seems to be lower in patients with recent transient ischaemic attack or ischaemic stroke than stated in previous studies. We found that higher age, male sex, White ethnicity, retinal ischaemia and current smoking were important risk factors for symptomatic internal carotid artery stenosis.

Validation of Risk Prediction Models to Detect Asymptomatic Carotid Stenosis

Background Significant asymptomatic carotid stenosis (ACS) is associated with higher risk of strokes. While the prevalence of moderate and severe ACS is low in the general population, prediction models may allow identification of individuals at increased risk, thereby enabling targeted screening. We identified established prediction models for ACS and externally validated them in a large screening population. Methods and Results Prediction models for prevalent cases with ≥50% ACS were identified in a systematic review (975 studies reviewed and 6 prediction models identified [3 for moderate and 3 for severe ACS]) and then validated using data from 596 469 individuals who attended commercial vascular screening clinics in the United States and United Kingdom. We assessed discrimination and calibration. In the validation cohort, 11 178 (1.87%) participants had ≥50% ACS and 2033 (0.34%) had ≥70% ACS. The best model included age, sex, smoking, hypertension, hypercholesterolemia, diabetes mellitus, vascular and cerebrovascular disease, measured blood pressure, and blood lipids. The area under the receiver operating characteristic curve for this model was 0.75 (95% CI, 0.74-0.75) for ≥50% ACS and 0.78 (95% CI, 0.77-0.79) for ≥70% ACS. The prevalence of ≥50% ACS in the highest decile of risk was 6.51%, and 1.42% for ≥70% ACS. Targeted screening of the 10% highest risk identified 35% of cases with ≥50% ACS and 42% of cases with ≥70% ACS. Conclusions Individuals at high risk of significant ACS can be selected reliably using a prediction model. The best-performing prediction models identified over one third of all cases by targeted screening of individuals in the highest decile of risk only.

Prevalence and risk factors of intracranial and extracranial artery stenosis in asymptomatic rural residents of 13 villages in China

Background

The present study aimed to investigate the prevalence and risk factors for extracranial carotid artery stenosis (ECAS) and intracranial carotid artery stenosis (ICAS) simultaneously in asymptomatic Chinese pure rural population.

Methods

We analyzed 2589 asymptomatic subjects aged over 30 yr. by ultrasonography and transcranial Doppler simultaneously in 13 isolated villages by door-to-door investigation. Both ECAS and ICAS were defined as more than 50% stenosis. Demographics, medical history documentation, and investigation of biochemical results were performed for each subject. Univariate and multivariate logistic regression analyses were employed to assess the risk factors associated with ECAS and ICAS, respectively.

Results

One hundred twenty-two (4.7%) residents with ICAS and 56 (2.2%) with ECAS were found in 2589 subjects. Three factors emerged as independent risk factors for ICAS: age (95% confidence interval [CI] = 1.01–1.04, odds ratio [OR] = 1.07), hypertension (95% CI = 1.98–4.37, OR = 2.94), and diabetes mellitus (95% CI = 1.72–4.38, OR = 2.75). As for ECAS, five factors presented as independent risk factors: age (95% CI = 1.09–1.11, OR = 1.10), male sex (95% CI = 1.01–1.02, OR = 1.01), diabetes mellitus (95% CI = 1.10–2.12, OR = 1.53), systolic blood pressure (95% CI = 1.95–2.88, OR = 2.37), and total cholesterol (95% CI = 1.00–1.13, OR = 1.06).

Conclusions

ICAS and ECAS were relatively common among asymptomatic rural Chinese subjects. Although they shared similar risk factors, differences still existed between them.

Internal Carotid Artery Occlusion: Association With Atherosclerotic Disease in Other Arterial Beds and Vascular Risk Factors

The aim of this article is to investigate the association between internal carotid artery occlusion (ICAO) and the presence of atherosclerotic disease and vascular risk factors. The clinical characteristics and risk factors of 120 patients presenting with ICAO were retrospectively reviewed. All patients (n = 120) had at least 1 of the 4 vascular risk factor (diabetes, smoking, hypercholesterolemia, and hypertension); 2, 3, or all 4 risk factors were present in 14 to 82 of the patients (11.7% to 68.3%), 10 to 39 of the patients (8.3% to 32.5%), and 9 of the patients (7.5%), respectively. A total of 84 patients (70%) with ICAO had disease in at least 1 additional vascular bed (aorta, coronary or lower limb arteries). In addition to ICAO, vascular disease was present in 2 and all 3 of these arterial beds in 42 (35%) and 9 (7.5%) patients, respectively. Furthermore, stenosis or occlusion of the ipsilateral or contralateral vertebral arteries was recorded in 19 of 120 patients (15.8%). Regarding the contralateral carotid artery, 1 patient had bilateral ICAO. One patient had contralateral common carotid artery occlusion, and 1 patient was excluded from the analysis because of surgery to the contralateral carotid artery. Of the remaining 117 patients, 34 (29.0%) had less than 50% contralateral carotid artery stenosis. Thirty-two patients (27.4%) had 50% to 69%, and 51 (43.6%) had 70% to 99% stenosis. Ultrasonographic imaging of the carotid plaque of the contralateral carotid artery revealed that 52 of the 120 arteries (43.3%) were uniformly or predominantly echolucent (types I and II, respectively). Fifty-nine (49.2%) were predominantly or uniformly echogenic (types III and IV), and 9 (7.5%) could not be classified. A similar distribution of echomorphology was observed on the occluded side. ICAO is associated with widespread atherosclerotic disease and a high prevalence of vascular risk factors. Detection of ICAO should prompt the investigation of other arterial beds and treatment of risk factors.

Effect of Carotid Artery Stenting on Cognitive Function in Patients with Internal Carotid Artery Stenosis and Cerebral Lacunar Infarction: A 3-Year Follow-Up Study in China

BACKGROUND AND OBJECTIVES

Carotid artery stenting (CAS) is an important therapeutic strategy for patients with carotid artery stenosis. However, the potential influence of CAS on cognitive function in patients with carotid artery stenosis and cerebral lacunar infarction has not been determined. This study investigated changes in cognitive function associated with CAS and the factors related to these changes.

METHODS

This prospective cohort study comprised 579 Chinese patients with cerebral lacunar infarction and carotid artery stenosis for whom CAS was indicated, and a matched control group of 552 healthy individuals. Cognitive function before CAS and at scheduled intervals from 6 months to 3 years was assessed with instruments that included the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scale. Potential factors that might affect cognitive function were analyzed via logistic regression.

RESULTS

The MMSE and MoCA scores of the patients before CAS were significantly lower than that of the control subjects. These scores were significantly higher 6 months after CAS and sustained or increased throughout the 3-year follow-up. Also significantly improved after CAS from baseline were scores for an alternating trail test, cube copying, clock-drawing, attention, and delayed recall in an auditory-verbal learning test. Logistic regression analyses showed that age greater than 65 y, little education, diabetes, and hypertension were independent risk factors for deteriorated MoCA scores 3 years after CAS.

CONCLUSION

CAS was associated with significantly improved cognitive function in cerebral lacunar infarction patients with severe stenosis.

Night time blood pressure and cardiovascular structure in a middle-aged general population in northern Italy: the Vobarno Study

The aim was to determine, in a cross-sectional study, the relation between structural alterations in the heart and carotid arteries, and blood pressure (BP) changes from day to night time, measured by ambulatory BP (ABP). In 225 untreated subjects (107 F, 118 M, age range 48-64 years) and 59 treated subjects (24 M, 35 F, age range 50-64), living in a small town of northern Italy (Vobarno, Brescia) carotid intima media thickness as well as the occurrence of plaque, were evaluated by ultrasound. Echocardiographic left ventricular (LV) mass was measured according to the Penn Convention. BP was determined by clinic measurement and by 24-h non-invasive ABP monitoring. Subjects were divided in two groups, according to the decrease of night time systolic BP (SBP) "dippers" (SBP decreased by at least 10% during night time) and "non-dippers" (decrease of night time SBP <10%). The intima-media thickness in the common carotid, in the carotid bifurcation, in the internal carotid artery and average intima-media thickness were significantly greater in untreated non-dippers as compared with dipper subjects (ANOVA P < 0.05). A significantly higher prevalence of plaque was observed in untreated non-dippers as compared with dippers (P = 0.002). After adjusting for age, sex, 24-h SBP, and smoking, IMT in the carotid bifurcation and average intima-media thickness remained significantly greater in non-dipper subjects (P < 0.05 for all comparisons). No significant differences in LV mass were observed between dippers and non-dipper subjects. In conclusion, in a general population of unselected middle-aged subjects, night time BP values, among other risk factors, seem to represent an important determinant of carotid wall structure.

Use of panoramic radiography among an ambulatory dental population to detect patients at risk of stroke

Panoramic radiographs of 3.6 percent of 1,175 newly accepted dental school patients displayed calcifications in the area of the carotid vasculature. The authors interviewed the patients with calcifications to determine whether they exhibited any recognized atherosclerosis, risk factors. One patient had symptoms of atherosclerosis, and a statistically significant correlation was found for obesity among the patients interviewed. The authors concluded that panoramic radiography is useful for identifying some asymptomatic patients with carotid calcifications. These patients should be referred to their physicians promptly for a cerebrovascular work-up as part of an active stroke-prevention strategy.

Risk factors differ for carotid artery plaque with and without acoustic shadowing. Atherosclerosis Risk in Communities Study Investigators

To investigate the association of gender, ethnicity, and several cardiovascular risk factors with carotid artery plaque and plaque with acoustic shadowing in a population-based sample, high-resolution B-mode ultrasonography was used to characterize lesions in the common and internal carotid arteries, and at the carotid bifurcation in 12,796 US men and women, aged 45 to 64 years, participating in the Atherosclerosis Risk in Communities Study (ARIC) baseline survey. In multiple logistic regression analyses, male gender (odds ratio and 95% confidence interval: 1.52 [1.39-1.67]) and increased total (1.47 [1.32-1.63]) and low-density-lipoprotein cholesterol (1.49 [1.34-1.65]) levels were statistically significantly associated only with the presence of plaque. In contradistinction, smoking (2.22 [1.79-2.75]) and hypertension (1.54 [1.30-1.82]) were additionally associated with acoustic shadowing. Hyperfibrinogenemia (1.33 [1.12-1.59]) was associated only with lesions accompanied by acoustic shadowing. While ethnicity associations with plaque alone varied across the artery segments, among those with plaque, being white was uniformly associated with acoustic shadowing. After multivariable adjustment, high-density-lipoprotein cholesterol was not associated with either manifestation of atherosclerosis. In conclusion, differences were seen in the associations of established cardiovascular risk factors with discretely characterized carotid artery plaque lesions, according to the presence or absence of acoustic shadowing suggestive of mineralization of plaque.

Cardiac and vascular structural changes. Prevalence and relation to ambulatory blood pressure in a middle-aged general population in northern Italy: the Vobarno Study

The aims of this study were to determine the prevalence of structural changes in the carotid arteries and heart and the correlation between these changes and the commonly recognized cardiovascular risk factors in the general population. Structural changes in the carotid arteries were defined as the intima-media thickness of the artery measured by B-mode ultrasound. Changes in the heart were defined as left ventricular mass index (LVMI) measured by echocardiography. LVMI values greater than 134 g/m2 in men and greater than 110 g/m2 in women were considered abnormal, indicating the presence of left ventricular hypertrophy. Blood pressure (BP) was measured in the clinic setting with a mercury sphygmomanometer and by 24-hour noninvasive ambulatory monitoring. Hypertension was defined as a sustained systolic BP greater than or equal to 160 mm Hg and/or diastolic BP increase greater than or equal to 95 mm Hg. The study population consisted of 225 subjects (107 women and 118 men) 48 to 64 years old. Prevalence of intima-media thickening (intima-media thickness > 1 mm) was 11% in normotensive subjects and 44% in hypertensive subjects. The presence of plaque (wall thickening with either mineralization or focal protrusion in the lumen at least 50% greater than the surrounding wall, usually > 2 mm) was observed in 35% of normotensive subjects and 44% of hypertensive subjects. The prevalence of left ventricular hypertrophy was 13% in normotensive subjects and 19% in hypertensive subjects. Intima-media thickness in the common and bifurcation segments of carotid arteries correlated well with LVMI (r = .20 and r = .19, respectively; P < .01). Intima-media thickness and LVMI were both positively related to 24-hour monitored BP (P < .01). However, in the multivariate analysis, body mass index (P = .027), sex (P < .001), and 24-hour mean BP (P = .025) were the most significant determinants of LVMI, whereas carotid artery intima-media thickness was found to be associated best with age (P < .001), cigarette smoking (P = .009), serum cholesterol (P = .025), serum glucose (P = .038), and nighttime systolic BP (P = .006). Logistic regression analysis confirmed the association between the presence of plaque and age (P < .001), nighttime systolic BP (P < .05), and cigarette smoking (P < .05); a negative association between plaque and the decrease in mean systolic BP daytime to nighttime was also observed (P < .001). In conclusion, in a general population of unselected middle-aged subjects, carotid wall thickness and LVMI were associated with each other and related to 24-hour BP levels although the major determinants of carotid wall and cardiac structure were different.

Evaluation of intracranial and extracranial carotid steno-occlusive diseases in Taiwan Chinese patients with MR angiography: preliminary experience

BACKGROUND AND PURPOSE

We attempted to evaluate the location of vascular lesions in cases of cerebrovascular steno-occlusive diseases in Chinese persons living in Taiwan.

METHODS

With three-dimensional time-of-flight magnetic resonance angiography (MRA) as a screening tool, 108 symptomatic patients with cerebrovascular steno-occlusive diseases were examined. Cardioembolic disease and cerebral hemorrhage cases were excluded. The degrees of stenosis of bilateral cervical carotid arteries and their major intracranial tributaries were recorded. They were categorized as nonsignificant stenosis (0% to 49%), significant stenosis (50% to 99%), and total occlusion.

RESULTS

Our data revealed that 32.4% of the cases were normal in either cervical carotid arteries or their intracranial tributaries. In 24.1% of the cases, significant extracranial carotid stenosis or occlusion was the only finding on MRA. In 25.9% of the cases, only significant intracranial-tributary stenosis was found. In 17.6% of them, significant lesions were found in both extracranial and intracranial carotid artery tributaries.

CONCLUSIONS

A racial difference between Chinese and white patients in location of lesion in cerebrovascular steno-occlusive diseases was confirmed. About one third of symptomatic Chinese patients living in Taiwan showed small-vessel disease. Approximately 24% of patients had only extracranial carotid disease, and about 26% had only intracranial carotid tributary disease. We need a larger series of patients to confirm these findings. However, MRA might be a good screening tool for steno-occlusive cerebrovascular disease, especially in persons of a race with more intracranial carotid disease, such as the Chinese.

Extracranial carotid atherosclerosis and vascular risk factors in different types of ischemic stroke in Taiwan

BACKGROUND AND PURPOSE

The clinical patterns of stroke and the angiographic distribution of cerebral atherosclerosis in Chinese people are different from those in whites. Studies relating carotid atherosclerosis and vascular risk factors to various types of stroke in Chinese people are lacking.

METHODS

Based on clinical information, we separated 367 stroke patients living in Taiwan into four subgroups: cortical infarction (CI), subcortical infarction (SCI), vertebrobasilar artery infarction (VBAI), and cardioembolic infarction (CEI). We assessed the extent and severity of extracranial carotid artery atherosclerosis in different types of ischemic stroke using duplex ultrasonography. Vascular risk factors and carotid atherosclerosis were then correlated with each subgroup of ischemic stroke.

RESULTS

Our data revealed that 32% of the CI subgroup, 3% of the SCI subgroup, 7% of the VBAI subgroup, and 21% of the CEI subgroup possessed severe carotid stenosis (> or = 50% stenosis or occlusion). The extent of atherosclerosis of extracranial carotid arteries, measured by plaque score, was also more severe in the CI subgroup than in the other subgroups. Diabetes mellitus was more frequent in the CI subgroup. Cardiomegaly and left ventricular hypertrophy were more commonly seen in the CEI subgroup. The VBAI subgroup was younger than the other subgroups. There were no differences in hypertension, prior stroke, alcohol intake, or serum levels of glucose, uric acid, hematocrit, lipids, and lipoproteins among the subgroups.

CONCLUSIONS

Of the Chinese patients living in Taiwan, the extent and severity of extracranial carotid artery atherosclerosis were more prominent in patients with CI than in patients with other types of ischemic stroke. In Chinese patients with CI, severe carotid stenosis is not uncommon; in Chinese patients with SCI, however, the frequency of carotid stenosis is quite low.

Carotid plaque, aging, and risk factors. A study of 457 subjects

BACKGROUND AND PURPOSE

The aim of this study was to assess the prevalence of extracranial carotid artery atherosclerosis and its relation to principal cardiovascular risk factors at different ages in a sample of the general population.

METHODS

B-mode ultrasonography was used to investigate the carotid district in 457 subjects (231 men and 226 women; mean age, 55.4 +/- 18.7 years; range, 18 to 97 years) in the metropolitan area. The ultrasonographic findings were then related to risk factors.

RESULTS

Carotid plaques were found in 178 subjects (38.9%). The prevalence of atherosclerosis, number of plaques, and severity of stenosis were observed to increase with age. Age (P < .0001), cigarette smoking (P < .0001), male sex (P < .001), total cholesterol (P < .05), and, inversely, the ratio of high-density lipoprotein cholesterol to total cholesterol (P < .05) were found to be independently associated with carotid atherosclerosis. Stratified analysis by sex and age showed effect modifications by age on cigarette smoking, total cholesterol, and the ratio of high-density lipoprotein cholesterol to total cholesterol. After multivariate analysis including interaction terms, cigarette smoking and cholesterol levels were not longer found to be associated with carotid atherosclerosis in elderly subjects. Age (P < .01), total cholesterol (P < .05), and diabetes (P < .05) were positively related to the severity of vascular narrowing.

CONCLUSIONS

There is a high prevalence of asymptomatic carotid atherosclerosis in the general population, particularly among the very old. The association between risk factors and carotid atherosclerosis is less pronounced in the elderly than in younger subjects.

Carotid plaques, aging, and risk factors for atherosclerosis

The prevalence of extracranial carotid artery atherosclerosis and its relations to principal cardiovascular risk factors at different ages was evaluated in a sample of general population. High resolution B-mode ultrasonography was used to investigate the carotid district in 457 subjects (231 males and 226 females, mean age 55.4+18.7 years, range 18-97 years) of the metropolitan area. The ultrasonographic findings were then related to primary risk factors. Carotid plaques were found in 178 subjects (38.5%). Prevalence of atherosclerosis, number of plaques and percentage of stenosis have been observed to increase with age. The main cardiovascular risk factors resulted significantly associated with carotid atherosclerosis in the total series and, more strongly, in subjects under 65 years. In the group aged 65 years and over, most of these associations were no longer found. In the multiple logistic regression model, analysis of subjects under 65 years showed positive and independent associations between carotid atherosclerosis and age (p<0.0001), cigarette smoking (p< 0.001), number of cigarettes smoked each day (p<0.01), and a negative association with HDL/total cholesterol ratio (p<0.001). The analysis of subjects aged 65 years or more showed positive independent associations only with age (p<0.001) and male gender (p<0.01). In conclusion, there is a high prevalence of asymptomatic carotid atherosclerosis in the general population, particularly in advanced age. In the elderly the association between risk factors and carotid atherosclerosis has not yet been found.

Early carotid atherosclerosis in healthy middle-aged women. A follow-up study

BACKGROUND AND PURPOSE

Few longitudinal data about early atherosclerotic lesions of the carotid arteries are available in general populations. The main purpose of this study was to investigate risk factors for development and regression of intimal-medial thickening and atheromatous plaques.

METHODS

Initial and 2-year examinations of the carotid arteries with high-resolution B-mode ultrasonography were performed in 308 apparently healthy women aged 45 to 55 years. The development of new atheromatous plaques and new intimal-medial thickening and the disappearance of preexisting plaques and intimal-medial thickening defined the four outcomes of interest.

RESULTS

The development of plaques occurred more frequently in women with intimal-medial thickening than in women with normal carotid arteries at baseline (14.4% versus 7.2%, P < .053). A regression was seen in 21.7% of the women with preexisting plaques. Development of intimal-medial thickening occurred in 47.5% of the women with normal carotid arteries whereas 20.2% of the women with preexisting intimal-medial thickening showed a regression of their lesions. Multiple logistic regression showed that smoking (regression coefficient +/- SE: 1.281 +/- 0.450; P < .005), baseline levels of systolic blood pressure (regression coefficient +/- SE: 0.031 +/- 0.015; P < .04) and apolipoprotein B (regression coefficient +/- SE: 0.016 +/- 0.007; P < .03) were independently associated with the development of plaques, whereas the presence of an intimal-medial thickening did not reach the significance level (regression coefficient +/- SE: 0.639 +/- 0.436; P < .15). Independent predictors of the development of intimal-medial thickening were age (regression coefficient +/- SE: 0.124 +/- 0.048; P < .04) and, with a borderline significance level, (log)triglycerides (regression coefficient +/- SE: 0.854 +/- 0.451; P < .06). Low levels of low-density lipoprotein cholesterol (regression coefficient +/- SE: 0.027 +/- 0.009; P < .004) were associated with its regression.

CONCLUSIONS

This longitudinal study emphasizes the interest of B-mode ultrasonography in the monitoring of early carotid lesions. It gives further support to the hypothesis that intimal-medial thickening may be an early indicator of the atherosclerotic process.

Risk factors for cervical atherosclerosis in patients with transient ischemic attack or minor ischemic stroke

BACKGROUND AND PURPOSE

Our purpose was to study potential determinants of the presence and the severity of cervical atherosclerosis in patients with transient ischemic attack or minor ischemic stroke.

METHODS

Two hundred ninety-four patients up to 60 years of age were included in this cross-sectional study. The male to female ratio was 171/123. Atherosclerosis was defined as the presence of any visible atherosclerotic lesion in anteroposterior or left oblique views of cervical arteries in aortic arch angiograms. The severity of atherosclerosis was assessed using three scores, which were computed separately for the total thickness and length of all plaques as well as for the percent stenosis of the vessels.

RESULTS

Atherosclerosis was present in 180 patients (61.2%). In a multiple stepwise logistic regression analysis, age, serum triglycerides, smoking history for more than 20 years, arterial hypertension (defined as systolic or diastolic blood pressure values at least 150 or 100 mm Hg, respectively, or the use of antihypertensive medication), regular light alcohol consumption (inversely), and body mass index (marginal inverse association) were independent determinants of the presence of atherosclerosis; the respective odds ratios were 1.1/1 y, 1.8/1 mmol/L, 3.3, 2.4, 0.3, and 0.9/1 kg/m2. In multiple linear regression models, age was associated positively and the ratio of high density lipoprotein to total cholesterol was associated negatively with the severity of atherosclerosis regardless of the scoring method, whereas current smoking and female sex were predictors only of the percent stenosis and the length of the lesions. Arterial hypertension showed a significant association only with the length of the lesions.

CONCLUSIONS

Age, cigarette smoking, and arterial hypertension contribute substantially to atherosclerosis in cervical arteries, but this study also confirms the independent associations of lipid or lipoprotein variables with atherosclerotic disease. An independent inverse association of regular light consumption of alcohol with cervical atherosclerosis was also observed.

Prevalence and risk factors of asymptomatic extracranial carotid artery atherosclerosis. A population-based study

To evaluate the prevalence and risk factors of asymptomatic carotid artery disease, we analyzed a sample of 909 men and women (aged 40-79 years) drawn from the community-based Bruneck Ischemic Heart Disease and Stroke Prevention Study. For the four decades of age (40-49, 50-59, 60-69, and 70-79 years), respective prevalence rates as assessed by duplex scanning were found to be 8.2%, 39.7%, 66.4%, and 82.5% in men and 3.3%, 22.3%, 48.7%, and 76.7% in women. High-grade stenosis (> 80%) classified by Doppler criteria was twice as frequent in men (2.4%) as in women (1.1%). Age and sex were found to be particularly strong and independent predictors of asymptomatic carotid artery disease. Accordingly, separate logistic regression models were developed for both men and women in the elderly (65-79 years) and middle-aged (50-64 years) groups. Systolic blood pressure turned out to be the only attribute with independent significance in all subgroups examined. Cigarette smoking, recorded as pack-years, emerged as the leading risk factor of carotid atherosclerosis in men. Serum fibrinogen levels were found to be highly indicative of carotid artery disease in elderly men and women. For apolipoprotein B predictive significance was observed in the middle-aged populations, whereas apolipoprotein A-I had a protective effect in elderly women. Diabetes mellitus completed the risk factor profile for elderly men. In summary, the relation between cardiovascular risk factors and asymptomatic carotid artery disease showed a dynamic dependence on sex and age. These findings may help to improve the efficacy of risk prediction in the general population and facilitate well-directed preventive measures.

Cardiovascular determinants of carotid artery disease. The Rotterdam Elderly Study

The objective of the present study was to assess the prevalence of moderate and severe stenosis of the right carotid artery in the elderly and its associations with smoking, blood pressure, serum lipid levels, and hemostatic factors. The Rotterdam Elderly Study is a recently started single-center prospective follow-up study of a cohort of 11,854 elderly people aged 55 years or more. In 1990, 954 participants of the Rotterdam Elderly Study underwent ultrasonic duplex examination of the right internal carotid artery. A reduction of the lumen diameter of 16-49% was found in 29 people (3.0%). Severe stenosis (50% or more) was observed in 13 people (1.4%). With differences in age, sex, and body mass index taken into account, subjects with moderate-to-severe carotid artery disease had, compared with participants without stenosis, lower mean high density lipoprotein cholesterol levels (mean difference, 0.10 mmol/l; 95% confidence interval, 0, 0.20) and higher mean fibrinogen levels (difference, 0.24 g/l; 0.04, 0.45). Among them were more people with hypertension (mean difference, 16%) and more current smokers (mean difference, 13%). Factor VIIc and factor VIIIc activity was higher in subjects with carotid artery disease, without, however, reaching statistical significance (mean difference, 0.06 IU/ml [-0.01, 0.12] and 0.21 IU/ml [-0.05, 0.47], respectively). Our data suggest that hypertension, smoking, and reduced serum high density lipoprotein cholesterol levels, combined with unfavorable increases in hemostatic factors, may be related to carotid artery disease in the elderly.