(Stroke. 1997;28:518-525.)
© 1997 American Heart Association, Inc.
Articles |
Prevalence of Asymptomatic Carotid Atherosclerotic Lesions Detected by High-Resolution Ultrasonography and Its Relation to Cardiovascular Risk Factors in the General Population of a Japanese City
The Suita Study
From the Department of Preventive Medicine, National Cardiovascular Center, Suita (T.M., S.B., N.N.); the Department of Public Health, Faculty of Medicine, Ehime University (M.K.); and the Tosayamada Public Health Center, Kochi (A.T.), Japan.
Correspondence to Toshifumi Mannami, MD, Department of Preventive Medicine, National Cardiovascular Center, Fujishirodai 5-7-1, Suita, Osaka, 565, Japan. E-mail mtoshi{at}hsp.ncvc.gojp.
 |
Abstract |
|---|
 Top Abstract IntroductionSubjects and MethodsResultsDiscussionReferences |
|---|
Background and Purpose Because extracranial carotid atherosclerotic lesions have been considered rare, no reports have been published on the prevalence and distribution of these lesions in a general Japanese population. However, recent changes in lifestyle are thought to have caused an increase in these lesions. The aim of this study was to use high-resolution ultrasonography to examine the prevalence of asymptomatic extracranial carotid artery lesions and its relation to cardiovascular risk factors in an urban Japanese population.
Methods The subjects were 814 men and 880 women aged 50 to 79 years randomly sampled from the residents of Suita, a city located in the second largest urban area of Japan. Asymptomatic carotid lesions were detected and evaluated by a single physician with high-resolution B-mode ultrasonography.
Results We found significant sex differences in the prevalence of atherosclerotic lesions in the extracranial carotid artery; 4.4% of all the subjects, 7.9% of the men, and 1.3% of the women had atherosclerosis accompanied by stenosis of >50%. A strong association between these lesions and the results of a 75-g oral glucose tolerance test was found in both sexes. Multiple regression analysis of carotid atherosclerosis showed significant relationships with age, systolic blood pressure, fasting blood glucose, pack-years of smoking, total serum cholesterol, and HDL cholesterol in men (P<.05) and significant relationships with age, systolic blood pressure, pack-years of smoking, and total serum cholesterol in women (P<.05).
Conclusions Our data showed that cardiovascular risk factors were strongly related to carotid atherosclerosis and that the proportion of severe carotid atherosclerosis with >50% stenosis was not low and was almost equal to that reported in developed western countries.
Key Words: atherosclerosis • carotid arteries • Japan • risk factors • ultrasonics
|
Introduction |
|---|
|
TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
|---|
In Japan, it has been thought that atherosclerotic lesions rarely occur in extracranial carotid arteries. Atherosclerosis has been more common in the intracranial than in the extracranial cerebral arteries in Japanese stroke patients compared with those in western countries.1 2 3 However, the lifestyle of the Japanese people, including diet, has been westernized, and as a result, the total serum cholesterol level of the Japanese has been rapidly increasing in recent decades. Moreover, the smoking rate is still high, especially in men, and there is a strong possibility that extracranial carotid lesions may be increasing and becoming more common. In fact, one angiographic study showed recently that severe atherosclerotic lesions are increasing in the extracranial ICA in Japanese patients with brain ischemia.4
Recently, it has become possible to detect and evaluate the minimal atherosclerotic lesions of the arterial wall with 7.5-MHz high-resolution B-mode ultrasonography.5 6 7 8 The carotid artery wall thickness measured by this device is currently used as a surrogate for intermediate end points of atherosclerosis in observational studies, and it has been documented as a good measure in evaluating regression or progression of atherosclerosis in clinical trials.9 10 11 12 13 14 15 16 It has also been recognized that the severity and progression of carotid atherosclerosis are associated with an increased risk of stroke and myocardial infarction.17 18 19 20 This noninvasive ultrasonic examination is also very useful for population-based epidemiological research.18 21 22 23 24 25 26 27 28 29 30 There have been no studies thus far using ultrasonography to determine the prevalence of extracranial atherosclerotic carotid lesions and their relationship with cardiovascular risk factors in a general population of Japan, although there are a few hospital-based studies on stroke patients.17 31 32 Some studies have found an association between asymptomatic extracranial carotid lesions and asymptomatic brain infarction, which is thought to be a risk factor for symptomatic brain infarction.32 33 34 35 36
The main aim of this study was to examine the prevalence of extracranial carotid atherosclerosis and its relationship with cardiovascular risk factors in an urban general population of Japan.
|
Subjects and Methods |
|---|
|
TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
|---|
The study population for this study is based on a random sample selected from the residents of Suita, a city located in the second largest urban area in Japan (Osaka area); the sample comprised 12 200 men and women aged 30 to 79 years. The basic sampling of the population started in 1989 with a cohort study base. The subjects have been visiting the National Cardiovascular Center every 2 years since then for regular health checkups. In addition to performing a routine blood examination that included total serum cholesterol, HDL cholesterol, triglyceride, and glucose levels and blood pressure and anthropometric measurements, a physician or nurse administered questionnaires covering personal and family history of cardiovascular and other diseases, as well as smoking and drinking habits. The carotid ultrasonic examinations were begun in April 1994 and were performed by a single physician. The subjects for this study included 814 men and 880 women, aged 50 to 79 years, who attended regular health checkups between April 1994 and July 1996. Among these subjects, 472 men and 492 women visited in the morning and were given 75-g oral glucose tolerance tests.
The subjects were classified as current smokers if they smoked at least
1 cigarette per day, nonsmokers if they had never smoked, and past
smokers if they had stopped smoking for more than 1 year. Subjects were
defined as hypertensive if DBP was 
95 mm Hg or SBP was
160 mm Hg or if they were taking antihypertensive medication.
Those subjects whose FBG levels were >7.78 mmol/L or >11.11
mmol/L at 2 hours after 75-g oral glucose loading, or who were taking
antidiabetic medication, were defined as diabetic. Subjects who had a
history of coronary heart disease or cerebrovascular disease were
excluded from this study (63 men and 29 women). The subjects' blood
was sampled after overnight fasting, resulting in 69 men and 88 women
being excluded because they did not meet this condition. Altogether,
132 men and 117 women among the total of 1694 subjects were excluded
from this analysis. Blood pressure was measured twice in the right arm
with a mercury sphygmomanometer, with the subject in a sitting position
after taking a short rest. The second measurement was used for the
analysis. Body mass index was calculated as weight (kilograms) divided
by height (meters) squared.
We used B-mode ultrasound imaging with 7.5-MHz transducers giving an axial resolution of 0.2 mm (apparatus, Toshiba SSA-250A; probe, SMA-736S mechanical sector scanner). All the examinations were performed by a single trained physician. The subject was in a supine position on a bed, and the extracranial carotid arteries were scanned bilaterally along three different longitudinal axes and a cross-sectional axis in the following manner. First, the CCA, ICA, and ECA were examined along a cross-sectional plane with the subject lying with jaw upright and turning his or her head to the other side while under examination. Second, the CCA, ICA, and ECA were examined along three different longitudinal plane axes, ie, the anterior-oblique, lateral, and posterior-oblique planes. Each measurement was made basically in the lateral plane, and the evaluation of stenosis was made in the cross-sectional plane. Third, the carotid artery of the other side was examined in the same way, with the subject lying with jaw upright and turning his or her head to the side under examination. The regions between 30 mm proximal from the beginning of the dilation of bifurcation bulb and 15 mm distal from the flow divider of both CCAs were scanned. The regions were divided into three segments, that is, the CCA region, bifurcation bulb region, and ICA region or ECA region. All measurements were made at the time of scanning with the instrument's electronic caliper and were recorded as photocopies. The IMT was measured on a longitudinal scan of the CCA at a point of 10 mm proximal from the beginning of the dilation of the bulb. IMT was defined as the mean of the IMT of the near and far walls at the point of measurement. Its scan pattern is characterized by two echogenic lines separated by a hypoechoic or anechoic space. The outer line corresponds to the medial-adventitial border and the inner line to the luminal-intimal border. Thus, the distance between the two parallel lines represents the IMT.5 31 We defined a plaque as an area where IMT was >1.10 mm and calculated the PN by counting the number of plaques in the bilateral carotid arteries in the scanning area. We also calculated the PS by totaling the maximum thicknesses of all the plaques in the same area. Finally, we defined stenosis as a condition in which a plaque occupies more than half of the luminal circumference of an artery on a cross-sectional scan, and the degree of stenosis was calculated as a percentage ratio of the area of the plaque to that of the lumen, using the following formula: (Lumen Area–Residual Lumen)/Lumen Areax100. Both of the areas were automatically measured by the system on a frozen transverse section at the maximal narrowing site. If there was >50% stenosis, another skilled ultrasonographer performed color flow Doppler examination to confirm the stenosis.
The intrareader reproducibility of the measurements was assessed for
the IMT of the CCA and the PN in 50 subjects just before the start of
this study. IMT and PN were examined twice at a 1-month interval in a
blinded manner for the correlation coefficient between the first and
second measurements of IMT (r=.87, P<.001).
Paired t test showed no statistically significant difference
between the two measurements. In addition, 94% of 
IMT (the
difference between the two measurements) was within a 2-SD (SD,
0.08 mm) range from the mean IMT (mean IMT, -0.02 mm).
As for PN, 74% of the first PN coincided with the second one
(
=0.68).
Blood samples drawn from the subjects after a fast of 12 hours or more were collected in EDTA-containing tubes. Total cholesterol and triglyceride levels were assayed enzymatically with a Toshiba TBA-80M biochemical discrete analyzer. Glucose was assayed enzymatically, and HDL cholesterol was measured after precipitation with heparin and calcium ions with a Toshiba TBA-20R biochemical discrete analyzer. The measurements of total cholesterol, HDL cholesterol, and triglyceride levels were all standardized in accordance with the protocol of the Centers for Disease Control and Prevention.
The Statistical Package for the Social Sciences (SPSS Inc) was used for the analysis. Mean age-adjusted levels of the three indexes of carotid atherosclerosis, namely IMT, PN, and PS, by 10-year age groups, sex, and individual coronary risk factors were obtained and tested by one-way ANOVA. For the comparisons for PN and PS, the significance tests were done after converting them into natural logarithms to make their distributions canonical. Relationships between these three indexes and cardiovascular risk factors were examined with multiple regression analysis in which each index was introduced as a dependent variable and cardiovascular risk factors as independent variables. Values of P<.05 were considered significant.
|
Results |
|---|
|
TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
|---|
Table 1
shows the characteristics of the
subjects by sex. The smoking rate for men is significantly higher than
for women as determined by 
2 test
(P<.05), and the percentage of diabetes mellitus for men is
also higher than for women. On the other hand, the Student's
t test results show that total serum cholesterol and HDL
cholesterol levels in women are significantly higher than in men
(P<.05). Other variables show no significant differences
between men and women.
|
There were sex differences and increasing tendencies with age in both
sexes, not only for all three indexes but also for IMT-MAX as shown in
Table 2. IMT-MAX is the maximum IMT within the scanned
area of this study. All indexes except for IMT are significantly higher
for men than for women for all 10-year age groups as determined by
Student's t test, and Scheffé's test shows
significant differences between individual 10-year age groups for both
sexes (P<.05).
|
Table 3 shows the distributions of PNs in the CCA,
bifurcation, ICA, and carotid artery searched in this study. Plaques in
the ECA were excluded from this analysis because there were few plaques
found there. There was a tendency for the proportion of subjects with
more than two plaques in the CCA and bifurcation to increase with age.
Table 3 also shows that in both sexes the proportion of subjects with
more than two plaques in the bifurcation was higher than that in those
with more than two plaques in the CCA or ICA. Furthermore, PN and PS
were generally higher for men than for women in the same 10-year age
group.
|
Table 4 shows the distribution of the degree of stenosis
for each 10-year age group by sex. The ratio of subjects in both sexes
with stenosis >25% gradually increases with age. Furthermore, this
table also shows that 4.4% of all the subjects, 7.9% of the men, and
1.3% of the women aged 50 to 79 years had a stenosis >50% and that
those values increased 6.5%, 11.1%, and 2.1% for the subjects aged
60 to 79 years, respectively.
|
As shown in Table 5, there were significant differences
as the result of ANCOVA using Scheffé's method
(P<.05) in IMT, PN, and PS among the groups of both sexes
classified by blood pressure level and also in all the atherosclerotic
indexes among the groups of both sexes classified by total serum
cholesterol level and in all the atherosclerotic indexes among the
groups of men classified by FBG level and by pack-years of smoking
level. Table 5 also shows age-adjusted IMT, PN, and PS of men and women
in the three subgroups categorized by 75-g oral glucose tolerance test
results using World Health Organization criteria, ie, normal or IGT and
diabetic pattern or under medical treatment for diabetes mellitus.
ANCOVA using Scheffé's method for two-group comparisons showed
statistically significant differences in men (P<.05)
between normal and diabetes groups and between IGT and diabetes groups
in IMT, between normal and IGT and between normal and diabetes groups
in PN, and between normal and IGT and between normal and diabetes, IGT,
and diabetes groups in PS. Similarly, in women there were significant
differences (P<.05) between normal and IGT groups in IMT,
PN, and PS.
|
The results of multiple regression analysis in which age, pack-years of
smoking, mean alcohol consumption per day, SBP, total serum
cholesterol, HDL cholesterol, triglyceride, and FBG were selected as
independent variables and IMT, IMT-MAX, PN, and PS as dependent
variables are shown in Tables 6 and 7.
For men, age, SBP, total cholesterol, HDL cholesterol, triglyceride,
pack-years of smoking, and FBG were significantly related to IMT
(P<.05 to <.0001), accounting for 34.4% of the
variability of this parameter (adjusted R2=.344,
F=34.329, P<.0001); age, SBP, and FBG were related to
IMT-MAX (P<.05 to <.0001; adjusted
R2=.158, F=12.916, P<.0001); age,
SBP, total cholesterol, HDL cholesterol, and pack-years of smoking were
related to PN (P<.05 to P<.0001; adjusted
R2=.254, F=22.626, P<.0001); and
age, SBP, total cholesterol, pack-years of smoking, and FBG were
related to PS (P<.05 to <.0001; adjusted
R2=.240, F=20.982, P<.0001).
Similarly, for women, age, SBP, total cholesterol, and pack-years of
smoking were significantly related to IMT (P<.05 to
<.0001; adjusted R2=.261, F=26.660,
P<.0001); and age and SBP were related to IMT-MAX, PN, and
PS (P<.05 to <.0001; adjusted
R2=.141, .185, and .187, respectively; F=12.970,
17.460, and 17.686; each P<.0001). Thus, all indexes of
carotid atherosclerosis showed a strong relationship with the
cardiovascular risk factors, with age accounting for the strongest
correlation with all of these atherosclerotic indexes for both
sexes.
|
|
|
Discussion |
|---|
|
TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
|---|
This is the first report based on a general Japanese population showing the prevalence rates of carotid atherosclerotic lesions, as assessed by high-resolution B-mode ultrasonography, and their association with cardiovascular risk factors.
For this study, the carotid ultrasonic examination was performed by a single physician because it is generally accepted that the intersonographer variability for B-mode measurements is greater than the intrasonographer variability.22
A plaque was defined as a lesion with an IMT of >1.10 mm within the scanned region of the carotid arteries in the present study. This definition is the same as that used by Handa and Matsumoto31 in their report on a study of Japanese persons free of stroke or myocardial infarction. We used this definition for our study because no other reliable criteria for carotid atherosclerosis in the Japanese could be found. In addition, the mean value of IMT in men 70 to 79 years of age is 1.02 mm, and indeed subjects in that age-sex group were found to have one or more plaques.
Although it is certain that the prevalence of plaque in CCAs is higher than that in ICAs, the regions of ICAs in this study were only 15 mm in length, half of the 30 mm of CCAs. This discrepancy was partly due to the large probe (SMA-736SA, mechanical sector scanner) of the Toshiba SSA-250A, which has a length of 74 mm and a width of 35 mm, making it anatomically difficult to scan a large area of ICA with this apparatus. In addition, it is said that the bifurcation of the carotid artery in the Japanese is generally located in a higher region of the neck than in occidentals. For these reasons, the ICA length scanned in this study was half that of the CCA. As a result, a smaller number of plaques were found in ICAs than in CCAs.
The proportion of subjects with more than two plaques at the bifurcation was higher than those for the CCA or ICA for both sexes. This indicates that the bifurcation is a favorite site for carotid atherosclerosis, a finding supported by some previous reports.37 38 Men usually had a larger IMT than women, and there was a tendency for both PN and PS to be greater for men than for women, also as shown in other reports.39 40 Furthermore, almost all atherosclerotic indexes for men were higher than for women, and the atherosclerotic process in men seemed to be about 10 years ahead of that in women. These results also correspond to some previous studies and agree with the fact that the incidence of coronary heart disease or stroke increases with age and is generally higher in men than in women.
The present study indicated, as shown in Table 4
, that 4.4% of the
present subjects aged 50 to 79 years, 7.9% of the men, and 1.3% of
the women had a stenosis level >50%. In contrast, in the Augsburg
MONICA population, >75% stenosis was observed in only 0.6% of the
participants aged 25 to 64 years,41 whereas Colgan et
al42 reported that only 4% of 348 participants screened
at a health fair (average age of 61 years) had stenosis >50% and only
1% had stenosis >80%. Langsfeld and Lusby43 also
reported that only 1% of 250 subjects aged over 40 years scanned at a
health fair had stenosis of >50%. In the Framingham Study, 8% of the
1189 members of the cohort aged 66 to 93 years had stenosis of
50%,44 and Pujia et al45 reported a
prevalence of 5% of flow-reducing stenosis >50% in subjects aged 75
years or older. Taking these results into consideration, it seems that
the prevalence of extracranial carotid atherosclerosis in Japan,
especially severe carotid atherosclerosis, is not only not low but may
be almost equal to that reported in western countries.
The mean±SD IMT in our population aged 50 to 79 years is 0.92±0.13 mm for men, 0.89±0.11 for women, and 0.91±0.12 for all subjects. On the other hand, the IMTs in the population aged 40 to 79 years of the Asymptomatic Carotid Artery Progression Study were 0.91±0.22 mm and 0.92±0.24 for the near and far walls of the left CCA and 0.92±0.22 and 0.92±0.23 for those of the right CCA, respectively.46 For the subjects aged 50 to 64 years in this study, the IMT was 0.87±0.11 mm for men and 0.86±0.10 for women. On the other hand, the IMTs in the Atherosclerosis Risk in Communities (ARIC) cohort were 0.84±0.26 mm and 0.75±0.21 for the left CCA of men and women and 0.82±0.26 and 0.76±0.22 for the right CCA of men and women, respectively.47 A comparison of the IMT in the population of this study with that in a major American study indicates that there is not much difference between the IMT of Japanese and Americans, even though there are several differences in the study procedures and conditions (ie, the apparatus, the techniques, the method of measuring carotid IMT, and the background of the population).
Furthermore, total serum cholesterol levels in Japan are rapidly increasing, now being 5.22 mmol/L for men and 5.65 mmol/L for women aged 50 to 79 years, according to the National Nutrition Survey of 1993. The levels of the subjects in the present study were 5.21 mmol/L for men and 5.72 mmol/L for women. The same 1993 survey reports that the smoking rate of men aged 50 to 79 years in Japan was nearly 45.0% and thus was much higher than that in other industrialized nations, although it is gradually decreasing. The prevalence of coronary heart disease in Japan is still lower than in western countries, but judging from these findings, there is a high possibility that extracranial carotid diseases and coronary heart disease will increase in the near future.
Ours is the first report showing a strong relationship between 75-g oral glucose tolerance test results and carotid atherosclerotic lesions in both sexes in a general Japanese population. Reports to date have shown significant relationships only between carotid lesions and fasting glucose or fasting insulin results.22 48
This study also showed a significant relationship between smoking and carotid atherosclerosis in Japanese men and women. Smoking already has been identified as a risk factor for carotid atherosclerosis in some studies, but all of them were for white subjects.13 21 30 37 49 50 51 52
Multiple regression analysis in the present study showed that there were significant correlations between the carotid atherosclerotic indexes and most of the established coronary risk factors for both sexes reported in other studies.18 20 29 39 50 53 54 55 56 57 In addition, of all risk factors for both sexes, age showed the strongest relationship with carotid atherosclerosis, as has also been shown in other reports.29 39 A strong relationship between atherosclerosis in the carotid and in the coronary artery has been identified in some previous studies.20 50 54 55 The ARIC study has recently published data supporting the relationship between prevalence of cardiovascular disease and arterial wall thickness in a population-based sample of US adults and reported that carotid wall thickness reflects cardiovascular disease manifest in other vascular beds, suggesting that the measurements reflect systemic atherosclerosis.18 It has also been reported that there are common risk factors for progression of the disease in the two arteries, ie, the carotid and coronary artery. Moreover, Crouse et al56 and Salonen et al57 have reported that several established coronary risk factors (age, HDL cholesterol, hypertension, LDL cholesterol, smoking) are associated with carotid lesions.
Finally, both the extracranial carotid and coronary artery are anatomically smooth muscle–type arteries and are located relatively close to each other. From these findings and facts, it can be reasonably inferred that carotid and coronary atherosclerosis are pathophysiologically similar.
In conclusion, the prevalence of asymptomatic carotid lesions in Japan is not low, although it should be noted that the population in the present study was restricted to an urban population. This study has also made it clear that there are strong relationships between most of the established cardiovascular risk factors and carotid atherosclerotic lesions. It is further suggested that the noninvasive method of examination used for this study is useful not only for epidemiological research but also for early detection of atherosclerosis related to stroke or coronary events. However, this is a cross-sectional study only; a longitudinal study is also needed to examine the relationships between carotid lesions and future cardiovascular events, ie, stroke and myocardial infarction, in the same subjects used for the present study.
|
Selected Abbreviations and Acronyms |
|---|
|
|
Acknowledgments |
|---|
We thank T. Ozaki, who worked as an ultrasonographer at the National Cardiovascular Center and is now at Koujunkai OBP Clinic in Osaka, for his kindness and advice and for teaching us his skillful technique for visualizing the carotid artery and training us for several months. We also express our appreciation to Jan K. Visscher for his careful advice on editing the manuscript.
Received October 21, 1996; revision received December 18, 1996; accepted December 18, 1996.
|
References |
|---|
|
TopAbstractIntroductionSubjects and MethodsResultsDiscussionReferences |
|---|
1. Kieffer SA, Takeya Y, Resch JA, Amplatz K. Racial differences in cerebrovascular disease: angiographic evaluation of Japanese and American population. AJR Am J Roentgenol.. 1967;101:94-99.
2. Tomita T, Mihara H. Cerebral angiographic study on C.V.D. in Japan. Angiology.. 1972;23:228-239.
3.
Brust RW Jr. Patterns of cerebrovascular disease in
Japanese and other population groups in Hawaii: an angiographic study.
Stroke.. 1975;6:539-542.
4. Nagao T, Sadoshima M, Ibayashi S, Takeya Y, Fujishima M. Increase in extracranial atherosclerotic carotid lesions in patients with brain ischemia in Japan. Stroke.. 1994;25:766-770. [Abstract]
5.
Pignoli P, Tremoli E. Intimal plus medial
thickness of arterial wall: a direct measurement with ultrasound
imaging. Circulation.. 1986;74:1399-1401.
6.
O'Leary DH, Bryan FA, Goodison MW, Rifkin MD, Gramiak
R, Ball M, Bond MG, Dunn RA, Goldberg BB, Toole JF, Wheller HG,
Gustafson N, Ekholm S, Raines J. Measurement variability of
carotid atherosclerosis: real-time (B-mode) ultrasonography and
angiography. Stroke.. 1987;18:1011-1017.
7. Bond MG, Barnes RW, Riley WA, Wilmoth SK, Chambless LE, Howard G, Owens B, for the ARIC Study Group. High-resolution B-mode ultrasound scanning methods in the Atherosclerosis Risk in Communities (ARIC) cohort. J Neuroimag.. 1991;1:68-73. [Medline] [Order article via Infotrieve]
8.
O'Leary DH, Polak JF, Wolfson SK, Bond ME, Bommer W,
Sheth S, Psaty BMN, Sharrett AR, Manolio TA. The use of
sonography to evaluate carotid atherosclerosis in the elderly: the
Cardiovascular Health Study. Stroke.. 1991;22:1155-1163.
9. Furberg CD, Byington RP, Borhani NA, for the MIDAS Research Group. Multicenter Isradipine Diuretic Atherosclerosis Study (MIDAS). Am J Med.. 1989;86:37-39. [Medline] [Order article via Infotrieve]
10.
Margiti SE, Bond MG, Crouse JR, Furberg CD, Probstfield
JL. Progression and regression of carotid atherosclerosis in
clinical trials. Arteriosclerosis.. 1991;11:443-451.
11.
ARIC Investigators. The Atherosclerosis Risk in
Communities (ARIC) Study: design and objectives. Am J
Epidemiol.. 1989;129:687-702.
12. Fried LP, Borhani NO, Enright P, Furberg CD, Gardin JM, Kronmal RA, Kuller LH, Manolio TA, Mittelmark MB, Newman A, O'Leary DH, Psaty B, Rautaharju P, Tracy RP, Weller PG. The Cardiovascular Health Study: design and rationale. Ann Epidemiol.. 1991;1:263-279. [Medline] [Order article via Infotrieve]
13.
Salonen R, Seppanen K, Rauramaa R, Salonen JT.
Prevalence of carotid atherosclerosis and serum cholesterol levels in
Eastern Finland. Arteriosclerosis.. 1988;8:788-792.
14. ACAPS Group. Rationale and design for the Asymptomatic Carotid Artery Plaque Study. Control Clin Trials.. 1992;13:293-314. [Medline] [Order article via Infotrieve]
15. Crouse JR, Byington RP, Bond MG, Espeland MA, Sprinkle JW, McGovern M, Furberg CD. Pravastatin, lipids, and atherosclerosis in the carotid arteries: design features of a clinical trial with carotid atherosclerosis outcome. Control Clin Trials.. 1992;13:495-506. [Medline] [Order article via Infotrieve]
16. Crouse JR, Byington RP, Bond MG, Espeland MA, Craven TE, Sprinkle JW, McGovern M, Furberg CD. Pravastatin, lipids, and atherosclerosis in the carotid arteries (PLAC-II ). Am J Cardiol.. 1995;75:455-459. [Medline] [Order article via Infotrieve]
17.
Handa N, Matsumoto M. Ischemic stroke events and
carotid atherosclerosis: results of the Osaka follow-up study for
ultrasonographic assessment of carotid atherosclerosis (the OSAKA
Study). Stroke.. 1995;26:1781-1786.
18.
Burke GL, Evance GW, Riley WA, Sharrett AR, Howard G,
Barnes RW, Rosamond W, Crow RS, Rautaharju PM, Heiss G, for the
Atherosclerosis Risk in the Communities (ARIC) Study Group. Arterial
wall thickness is associated with prevalent cardiovascular disease in
middle-aged adults: the Atherosclerosis Risk in Communities (ARIC)
Study. Stroke.. 1995;26:386-391.
19.
Bots ML, Breslau PJ, Briet E, de Brnyn AM, van Vliet
HHDM, van den Ouweland FA, de Jong PTVM, Hofman A, Grobbee DE.
Cardiovascular determinants of carotid artery disease: the Rotterdam
Elderly Study. Hypertension.. 1992;19:717-720.
20. Craven TE, Ryu JE, Espeland MA, Kahl FR, McKinney WM, Toole JF, McMahan MR, Thompson CJ, Heiss G, Crouse JR. Evaluation of the association between carotid artery atherosclerosis and coronary artery stenosis. Circulation. 1990;21:3-16.
21. Salonen R, Salonen JT. Progression of carotid atherosclerosis and its determinants: a population-based ultrasonography study. Atherosclerosis.. 1990;81:33-40. [Medline] [Order article via Infotrieve]
22.
Bonithon-Kopp C, Jouven X, Taquet A, Touboul PJ, Guize
L, Scarabin PY. Early carotid atherosclerosis in healthy
middle-aged women: a follow-up study. Stroke.. 1993;24:1837-1843.
23.
Howard G, Sharrett AR, Gerardo H, Evans GW, Chambless
LE, Riley WA, Burke GL, for the Atherosclerosis Risk in Communities
(ARIC) Study Investigators. Carotid artery intimal-medial thickness
distribution in general populations as evaluated by B-mode ultrasound.
Stroke.. 1993;24:1297-1304.
24. Li R, Duncann BB, Metcalf PA, Crouse JR, Sharrett AR, Tyroler HA, Barnes R, Heiss G, for the Atherosclerosis Risk in Communities (ARIC) Study Investigators. B-mode detected carotid artery plaque in a general population. Stroke.. 1994;25:2377-2383. [Abstract]
25.
Fine-Edelstein JS, Wolf PA, O'Leary DH, Poehlman H,
Belanger AJ, Kase CS, D'Agostino RB. Precursors of extracranial
carotid atherosclerosis in the Framingham study.
Neurology.. 1994;44:1046-1050.
26.
Castellano M, Muiesan ML, Rizzoni D, Beschi M, Pasini
G, Cinelli A, Salvetti M, Porteri E, Bettoni G, Kreutz R, Lindpaintner
K, Rosei AR. Angiotensin-converting enzyme
I/D polymorphism and arterial wall thickness in a general
population: the Vobarno Study. Circulation.. 1995;91:2721-2724.
27. Pignoli P. Ultrasound B-mode imaging for arterial wall thickness measurement. Atheroscler Rev.. 1984;12:177-184.
28. Poli A, Tremoli E, Colombo A, Sirtori M, Pignoli P, Paoletti R. 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. Atherosclerosis.. 1988;70:253-261. [Medline] [Order article via Infotrieve]
29.
Bonithon-Kopp C, Scarabin PY, Taquet A, Touboul PJ,
Malmejac A, Guize L. Risk factors for early carotid
atherosclerosis in middle-aged French women. Arterioscler
Thromb.. 1991;11:966-972.
30.
Prati P, Vanuzzo O, Casaroli M, DiChiara A, DeBiasi F,
Fruglio GA, Touboul PJ. Prevalence and determinants of carotid
atherosclerosis in a general population. Stroke.. 1992;23:1705-1711.
31.
Handa N, Matsumoto M. Ultrasonic evaluation of
early carotid atherosclerosis. Stroke.. 1990;21:1567-1572.
32. Handa N, Matsumoto M. An ultrasonic study of the relationship between extracranial carotid atherosclerosis and ischemic cerebrovascular disease in Japanese. Jpn J Geriatr.. 1992;29:742-747.
33.
Special report from the National Institute of
Neurological Disorders and Stroke: classification of cerebrovascular
disease III. Stroke.. 1990;21:637-676.
34. Hougaku H, Matsumoto M. Asymptomatic carotid lesions and silent cerebral infarction. Stroke.. 1994;25:566-570. [Abstract]
35. Brott T, Tomsick T, Feinberg W. Baseline-silent cerebral infarction in the Asymptomatic Carotid Atherosclerosis Study. Stroke.. 1994;25:1122-1129. [Abstract]
36.
Norris JW, Zhu CZ. Silent stroke and carotid
stenosis. Stroke.. 1992;23:483-485.
37. Tell GS, Howard G, McKinney WM. Risk factors for site-specific extracranial carotid artery plaque distribution as measured by B-mode ultrasound. J Clin Epidemiol.. 1989;42:551-559. [Medline] [Order article via Infotrieve]
38.
Durward QJ, Ferguson GG, Barr HWK. The natural
history of asymptomatic carotid bifurcation. Stroke.. 1982;13:459-464.
39. Fabris F, Zanocchi M, Bo M, Fonte G, Poll L, Bergoglio I, Ferrario E, Pernigotti L. Carotid plaque, aging, and risk factors: a study of 457 subjects. Stroke.. 1994;25:1133-1140. [Abstract]
40. Howard G, Burke GL, Evans GW, Crouse JR, Riley W, Arnett D, de Lacy R, Heiss G, for the Atherosclerosis Risk in Communities (ARIC) Investigators. Relations of intimal-medial thickness among sites within the carotid artery as evaluated by B-mode ultrasound. Stroke.. 1994;25:1581-1587. [Abstract]
41. Gostomzyk JG, Heller WD, Gerhardt P, Lee PN, Keil U. B-scan ultrasound examination of the carotid arteries within a representative population (MONICA Project Augsburg). Klin Wochenschr. 1988;66(suppl 11):58-65.
42. Colgan MP, Strode GR, Sommer DJ, Gibbs JL. Prevalence of asymptomatic carotid disease: results of duplex scanning in 348 unselected volunteers. J Vasc Surg.. 1988;8:674-678. [Medline] [Order article via Infotrieve]
43. Langsfeld M, Lusby RJ. The spectrum of carotid artery disease in asymptomatic patients. J Cardiovasc Surg.. 1988;29:687-691. [Medline] [Order article via Infotrieve]
44. O'Leary DH, Anderson KM, Wolf PA, Evans JC, Poehlman HW. Cholesterol and carotid atherosclerosis in older persons: the Framingham Study. Ann Epidemiol. 1992;2:147-153.[Medline] [Order article via Infotrieve]
45.
Pujia A, Rubba P, Spencer MP. Prevalence of
extracranial carotid artery disease detectable by echo-Doppler in an
elderly population. Stroke.. 1992;23:818-822.
46. Espeland MA, Hoen H, Byington R, Howard G, Riley WA, Furberg CD. Spatial distribution of carotid intimal-medial thickness as measured by B-mode ultrasonography. Stroke.. 1994;25:1812-1819. [Abstract]
47.
Crouse JR, Goldbourt U, Evans G, Pinsky J, Sharrett AR,
Sorlie P, Riley W, Heiss G, for the ARIC investigators. Risk factors
and segment-specific carotid arterial enlargement in the
Atherosclerosis Risk in Communities (ARIC) cohort. Stroke.. 1996;27:69-75.
48. Folsom AR, Eckfeldt JH, Weitzman S, Ma J, Chambless LE, Barnes RW, Cram KB, Hutchinson RG, for the Atherosclerosis Risk in Communities (ARIC) Study Investigators. Relation of carotid artery wall thickness to diabetes mellitus, fasting glucose and insulin, body size, and physical activity. Stroke.. 1994;25:66-73. [Abstract]
49.
Dempsey RJ, Moore RW. Amount of smoking
independently predicts carotid artery atherosclerosis severity.
Stroke.. 1992;23:693-696.
50.
O'Leary DH, Polak JF, Kronmal RA, Kittner SJ, Bond MG,
Wolfson SK Jr, Bommer W, Price TR, Gardin JM, Savage PJ.
Distribution and correlates of sonographically detected carotid artery
disease in the Cardiovascular Health Study: the CHS Collaborative
Research Group. Stroke.. 1992;23:1752-1760.
51. Jungquist G, Hanson BS, Isacsson SO, Janzon L, Steen B, Lindell SE. Risk factors for carotid artery stenosis: an epidemiological study of men aged 69 years. J Clin Epidemiol.. 1991;44:347-353. [Medline] [Order article via Infotrieve]
52.
Whisnant JP, Homer D, Ingall TJ, Baker HL, O'Fallon
WM, Wiebers DO. Duration of cigarette smoking is the strongest
predictor of severe extracranial carotid artery
atherosclerosis. Stroke.. 1990;21:707-714.
53. Salonen R, Salonen JT. Carotid atherosclerosis in relation to systolic and diastolic blood pressure: Kuopio Ischemic Heart Disease Risk Factor Study. Ann Med.. 1991;23:23-27. [Medline] [Order article via Infotrieve]
54.
Solberg LA, Strong JP. Risk factors and
atherosclerotic lesions: a review of autopsy studies.
Arteriosclerosis.. 1983;3:187-198.
55.
Salonen JT, Salonen R. Ultrasonographically
assessed carotid morphology and the risk of coronary heart
disease. Arterioscler Thromb.. 1991;11:1245-1249.
56.
Crouse JR, Toole JF, McKinney WM, Dignan MB,
Howard G, Kahl FR, McMahan MR, Harpold GH. Risk factors for
extracranial carotid artery atherosclerosis. Stroke.. 1987;18:990-996.
57. Salonen JT, Seppanen K, Rauramaa R, Salonen R. Risk factors for carotid atherosclerosis: the Kuopio Ischemic Heart Disease Risk Factor Study. Ann Med.. 1989;21:227-229.[Medline] [Order article via Infotrieve]
This article has been cited by other articles:
 |
|
 |
|
  M. de Weerd, J. P. Greving, A. W.F. de Jong, E. Buskens, and M. L. Bots Prevalence of Asymptomatic Carotid Artery Stenosis According to Age and Sex: Systematic Review and Metaregression Analysis Stroke, April 1, 2009; 40(4): 1105 - 1113. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Murakami, A. Hozawa, T. Okamura, H. Ueshima, and the Evidence for Cardiovascular Prevention From Ob Relation of Blood Pressure and All-Cause Mortality in 180 000 Japanese Participants: Pooled Analysis of 13 Cohort Studies Hypertension, June 1, 2008; 51(6): 1483 - 1491. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Demircan, A. T. Sezgin, M. Baltali, O. Gulcan, S. Topcu, F. Yigit, T. Erol, R. Turkoz, H. Muderrisoglu, and B. Ozin Intima-Media Thickness in Patients With Rheumatic Mitral Stenosis Angiology, November 1, 2007; 58(5): 614 - 619. [Abstract] [PDF]
|
|
|
|
|
|
N. Iwai, K. Kajimoto, H. Tomoike, and N. Takashima Polymorphism of CYP11B2 Determines Salt Sensitivity in Japanese Hypertension, April 1, 2007; 49(4): 825 - 831. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Napoli, L. O. Lerman, F. de Nigris, M. Gossl, M. L. Balestrieri, and A. Lerman Rethinking Primary Prevention of Atherosclerosis-Related Diseases Circulation, December 5, 2006; 114(23): 2517 - 2527. [Full Text] [PDF]
|
|
|
|
 |
|
 M Allocca, A Crosignani, A Gritti, G Ghilardi, D Gobatti, D Caruso, M Zuin, M Podda, and P M Battezzati Hypercholesterolaemia is not associated with early atherosclerotic lesions in primary biliary cirrhosis Gut, December 1, 2006; 55(12): 1795 - 1800. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Iwai, K. Kajimoto, Y. Kokubo, and H. Tomoike Extensive Genetic Analysis of 10 Candidate Genes for Hypertension in Japanese Hypertension, November 1, 2006; 48(5): 901 - 907. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Makita, A. Ohira, Y. Naganuma, Y. Moriai, H. Niinuma, A. Abiko, and K. Hiramori Increased Carotid Artery Stiffness Without Atherosclerotic Change in Patients With Aortic Dissection Angiology, August 1, 2006; 57(4): 478 - 486. [Abstract] [PDF]
|
|
|
|
 |
|
 R. A Wyman, M. E Mays, P. E McBride, and J. H Stein Ultrasound-detected carotid plaque as a predictor of cardiovascular events Vascular Medicine, May 1, 2006; 11(2): 123 - 130. [Abstract] [PDF]
|
|
|
|
 |
|
 H. Yokoyama, M. Kawasaki, Y. Ito, S. Minatoguchi, and H. Fujiwara Effects of Fluvastatin on the Carotid Arterial Media as Assessed by Integrated Backscatter Ultrasound Compared With Pulse-Wave Velocity J. Am. Coll. Cardiol., December 6, 2005; 46(11): 2031 - 2037. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Tanimoto, Y. Ikari, K. Tanabe, S. Yachi, H. Nakajima, T. Nakayama, M. Hatori, G. Nakazawa, Y. Onuma, Y. Higashikuni, et al. Prevalence of Carotid Artery Stenosis in Patients With Coronary Artery Disease in Japanese Population Stroke, October 1, 2005; 36(10): 2094 - 2098. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Vryonidou, A. Papatheodorou, A. Tavridou, T. Terzi, V. Loi, I.-A. Vatalas, N. Batakis, C. Phenekos, and A. Dionyssiou-Asteriou Association of Hyperandrogenemic and Metabolic Phenotype with Carotid Intima-Media Thickness in Young Women with Polycystic Ovary Syndrome J. Clin. Endocrinol. Metab., May 1, 2005; 90(5): 2740 - 2746. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. W. Dodick, I. Meissner, F. B. Meyer, and H. J. Cloft Evaluation and Management of Asymptomatic Carotid Artery Stenosis Mayo Clin. Proc., July 1, 2004; 79(7): 937 - 944. [Abstract] [PDF]
|
|
|
|
|
|
G. B. J. Mancini, B. Dahlof, and J. Diez Surrogate Markers for Cardiovascular Disease: Structural Markers Circulation, June 29, 2004; 109(25_suppl_1): IV-22 - IV-30. [Full Text] [PDF]
|
|
|
|
|
|
F. Monzani, N. Caraccio, M. Kozakowa, A. Dardano, F. Vittone, A. Virdis, S. Taddei, C. Palombo, and E. Ferrannini Effect of Levothyroxine Replacement on Lipid Profile and Intima-Media Thickness in Subclinical Hypothyroidism: A Double-Blind, Placebo- Controlled Study J. Clin. Endocrinol. Metab., May 1, 2004; 89(5): 2099 - 2106. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Inamoto, T. Katsuya, Y. Kokubo, T. Mannami, T. Asai, S. Baba, J. Ogata, H. Tomoike, and T. Ogihara Association of Methylenetetrahydrofolate Reductase Gene Polymorphism With Carotid Atherosclerosis Depending on Smoking Status in a Japanese General Population Stroke, July 1, 2003; 34(7): 1628 - 1633. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K-T Khaw and P D Griffiths Non-invasive imaging of the cervical carotid and vertebral arteries Imaging, December 15, 2001; 13(5): 376 - 390. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. A. BENEDETTO, F. MALLAMACI, G. TRIPEPI, and C. ZOCCALI Prognostic Value of Ultrasonographic Measurement of Carotid Intima Media Thickness in Dialysis Patients J. Am. Soc. Nephrol., November 1, 2001; 12(11): 2458 - 2464. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Iwai, S. Baba, T. Mannami, T. Katsuya, J. Higaki, T. Ogihara, and J. Ogata Association of Sodium Channel {gamma}-Subunit Promoter Variant With Blood Pressure Hypertension, July 1, 2001; 38(1): 86 - 89. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Mannami, T. Katsuya, S. Baba, N. Inamoto, K. Ishikawa, J. Higaki, T. Ogihara, and J. Ogata Low Potentiality of Angiotensin-Converting Enzyme Gene Insertion/Deletion Polymorphism as a Useful Predictive Marker for Carotid Atherogenesis in a Large General Population of a Japanese City : The Suita Study Stroke, June 1, 2001; 32(6): 1250 - 1256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Ishikawa, S. Baba, T. Katsuya, N. Iwai, T. Asai, M. Fukuda, S. Takiuchi, Y. Fu, T. Mannami, J. Ogata, et al. T+31C Polymorphism of Angiotensinogen Gene and Essential Hypertension Hypertension, February 1, 2001; 37(2): 281 - 285. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P.M. Rothwell The Interrelation between carotid, femoral and coronary artery disease Eur. Heart J., January 1, 2001; 22(1): 11 - 14. [PDF]
|
|
|
|
|
|
T. Mannami, S. Baba, and J. Ogata Potential of Carotid Enlargement as a Useful Indicator Affected by High Blood Pressure in a Large General Population of a Japanese City : The Suita Study Stroke, December 1, 2000; 31(12): 2958 - 2965. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Baldassarre, M. Amato, A. Bondioli, C. R. Sirtori, and E. Tremoli Carotid Artery Intima-Media Thickness Measured by Ultrasonography in Normal Clinical Practice Correlates Well With Atherosclerosis Risk Factors Stroke, October 1, 2000; 31(10): 2426 - 2430. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Mannami, S. Baba, and J. Ogata Strong and Significant Relationships Between Aggregation of Major Coronary Risk Factors and the Acceleration of Carotid Atherosclerosis in the General Population of a Japanese City: The Suita Study Arch Intern Med, August 14, 2000; 160(15): 2297 - 2303. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Schmidt, J. Hulthe, J. Wikstrand, H. Gnarpe, J. Gnarpe, S. Agewall, and B. Fagerberg Chlamydia pneumoniae Seropositivity Is Associated With Carotid Artery Intima-Media Thickness Stroke, July 1, 2000; 31(7): 1526 - 1531. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Higaki, S. Baba, T. Katsuya, N. Sato, K. Ishikawa, T. Mannami, J. Ogata, and T. Ogihara Deletion Allele of Angiotensin-Converting Enzyme Gene Increases Risk of Essential Hypertension in Japanese Men : The Suita Study Circulation, May 2, 2000; 101(17): 2060 - 2065. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Greenland, J. Abrams, G. P. Aurigemma, M. G. Bond, L. T. Clark, M. H. Criqui, J. R. Crouse III, L. Friedman, V. Fuster, D. M. Herrington, et al. Prevention Conference V : Beyond Secondary Prevention : Identifying the High-Risk Patient for Primary Prevention : Noninvasive Tests of Atherosclerotic Burden : Writing Group III Circulation, January 4, 2000; 101 (1): e16 - e22. [Full Text] [PDF]
|
|
|
|
|
|
N. Iwai, T. Katsuya, K. Ishikawa, T. Mannami, J. Ogata, J. Higaki, T. Ogihara, T. Tanabe, and S. Baba Human Prostacyclin Synthase Gene and Hypertension : The Suita Study Circulation, November 30, 1999; 100(22): 2231 - 2236. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Jensen-Urstad, M. Jensen-Urstad, and J. Johansson Carotid Artery Diameter Correlates With Risk Factors for Cardiovascular Disease in a Population of 55-Year-Old Subjects Stroke, August 1, 1999; 30(8): 1572 - 1576. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. A. Lakka, R. Salonen, G. A. Kaplan, and J. T. Salonen Blood Pressure and the Progression of Carotid Atherosclerosis in Middle-Aged Men Hypertension, July 1, 1999; 34(1): 51 - 56. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Ebrahim, O. Papacosta, P. Whincup, G. Wannamethee, M. Walker, A. N. Nicolaides, S. Dhanjil, M. Griffin, G. Belcaro, A. Rumley, et al. Carotid Plaque, Intima Media Thickness, Cardiovascular Risk Factors, and Prevalent Cardiovascular Disease in Men and Women : The British Regional Heart Study Stroke, April 1, 1999; 30(4): 841 - 850. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. H. O'Leary, J. F. Polak, R. A. Kronmal, T. A. Manolio, G. L. Burke, S. K. Wolfson, and The Cardiovascular Health Study Collaborative Rese Carotid-Artery Intima and Media Thickness as a Risk Factor for Myocardial Infarction and Stroke in Older Adults N. Engl. J. Med., January 7, 1999; 340(1): 14 - 22. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M.-L. M. Gronholdt Ultrasound and Lipoproteins as Predictors of Lipid-Rich, Rupture-Prone Plaques in the Carotid Artery Arterioscler Thromb Vasc Biol, January 1, 1999; 19(1): 2 - 13. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||