(Stroke. 1997;28:348-353.)
© 1997 American Heart Association, Inc.
Articles |
the Department of Radiology, Royal Infirmary of Edinburgh National Health Service Trust (P.L.A.), and the Wolfson Unit for Prevention of Peripheral Vascular Diseases, Department of Public Health Sciences, Medical School (P.I.M., A.J.L., F.G.R.F.), Edinburgh, Scotland.
Correspondence to Professor F.G.R. Fowkes, Wolfson Unit for Prevention of Peripheral Vascular Diseases, Department of Public Health Sciences, Medical School, Teviot Place, Edinburgh EH8 9AG, Scotland. E-mail gerry.fowkes@ed.ac.uk.
| Abstract |
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Methods Ultrasonic evaluation of IMT was included in the 5-year follow-up examination of participants of the Edinburgh Artery Study. Valid readings of IMT were recorded in 1106 subjects aged 60 to 80 years, and the maximum from the right and left sides of the neck was used in the analysis. Existing symptomatic and asymptomatic peripheral arterial disease and coronary heart disease were also assessed at follow-up using previously validated noninvasive techniques.
Results IMT increased continuously with age (P
.01), and its distribution was positively skewed in both sexes. The results suggest that levels of atherosclerotic development in the common carotid artery are 5 to 10 years more advanced in men than in women. In this population, the overall prevalence of moderate to severe disease was very low (only 1.2% of study participants had IMT values >2 mm). The presence of symptomatic (intermittent claudication) or asymptomatic (ankle brachial pressure index
0.9) peripheral arterial disease was significantly associated with increased IMT (P
.05).
Conclusions Although the prevalence of advanced atherosclerosis was very low, small changes in IMT were associated with clinically significant development of atherosclerosis in the peripheral arteries. However, further longitudinal studies are needed that standardize measurement techniques and would allow accurate comparisons across studies.
Key Words: peripheral vascular diseases atherosclerosis carotid arteries duplex scanning
| Introduction |
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It has also been shown that atherosclerotic lesions in their earliest stages may progress without a reduction in lumen diameter because of simultaneous dilation of the arterial wall,14 15 16 making recognition of stenosis on arteriography difficult. Because ultrasonographic measurement of the IMT is not affected by lumen diameter, it may therefore be the most accurate method of assessing early development of atherosclerosis in large representative population samples. Unfortunately, few recent studies have measured IMT as the primary disease variable8 9 16 17 18 ; many have used the presence of stenotic plaques, which are relatively late manifestations, as measures of disease severity.4 5 6 19 20 21
Although ARIC demonstrated a relationship between carotid IMT and preexisting symptomatic peripheral arterial disease,22 Bots et al23 are the only authors to report an association between IMT and asymptomatic peripheral arterial disease within a general population. Similarly, the Edinburgh Artery Study assesses noninvasively both carotid atherosclerosis and peripheral arterial disease in a large representative population sample. The main objectives of this report are (1) to describe the distribution of ultrasonographically detected CCA IMT and (2) to assess the relationship between CCA IMT and noninvasively assessed peripheral arterial disease.
| Subjects and Methods |
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Identification of Cardiovascular Events
Throughout the 5-year follow-up, a range of cardiovascular events was recorded using criteria adapted from the American Heart Association.25 Details concerning procedures used to identify fatal and nonfatal cardiovascular events have been described previously.26 In brief, records were flagged at the UK National Health Service Central Registry to identify deaths. Information on nonfatal events was sought from general practitioners, hospitals, and the Information Services Division of the Scottish Office Home and Health Department and by annual questionnaire to the participants. All cardiovascular events and deaths were further investigated using hospital or general practice notes. For the current cross-sectional analysis, intermittent claudication was recorded if either of the following was true: (1) evidence27 of intermittent claudication by WHO criteria (grade 1, 2, or probable28 ) at baseline or during follow-up or (2) clinical diagnosis of intermittent claudication investigated by the general practitioner or hospital. Angina pectoris was recorded if there was WHO evidence of angina plus either subject recall of a doctor's diagnosis or electrocardiographic evidence of ischemia at either baseline or during follow-up. Subjects were recorded as having had a myocardial infarction if any two of WHO evidence, electrocardiographic evidence, or subject recall of a doctor's diagnosis existed at baseline or follow-up examination. In addition, myocardial infarctions recorded during follow-up were also included. Coronary heart disease was defined as either angina pectoris or myocardial infarction defined by the above criteria.
Five-Year Follow-up Examination
A total of 1156 subjects attended the 5-year follow-up examination between November 1992 and March 1994. Complete details of this examination procedure have been described previously.26 Briefly, subjects completed a self-administered questionnaire that included questions concerning new cardiovascular events, personal characteristics, the WHO angina and intermittent claudication questionnaires,27 smoking history, and current medication.
After 5 minutes of rest, right-arm brachial systolic and diastolic blood pressures were measured using a Hawksley random zero sphygmomanometer. Femoral, posterior tibial, and dorsalis pedis arteries were then palpated, and ankle pressures were measured using a Sonicaid Doppler ultrasound probe.
The B-mode ultrasound scanning of the carotid arteries was performed using an ATL UM9, HDI Duplex Scanner (Bothwell). A 10-MHz transducer was used to provide imaging at 10 MHz and spectral Doppler at 7 MHz. The subject lay supine with the neck extended and the chin turned contralateral to the side being examined. The scanning protocol involved examination of the carotid arteries first in a transverse plane and then longitudinally. A record was made as to whether each of the four arterial segments (internal, external, common carotid, and bulb) was identifiable on each side. Measurement of IMT was made at a point on the far wall of the CCA, 2 cm proximal to the bifurcation, from a longitudinal scan plane that showed the intima-media boundaries most clearly. It was decided to measure the IMT at this section of the carotid artery because it is well documented that accuracy of visualization of vessels, and particularly the intima-media boundary, on B-mode ultrasound images is related to depth and anatomic configuration of the vessel.29 30 31 32 Furthermore, CCA IMT has been shown to be as strong a predictor of disease as IMT measured within the internal carotid artery.18 On the screen displaying the frozen magnified image of the far wall of the CCA, two cursors were positioned on the boundaries of the intima-media. The distance between these cursors was recorded to the nearest 0.1 mm (maximum axial resolution of the scanner) as the IMT. The procedure was repeated for each side of the neck.
All scan images were recorded on videotape, and any images of insufficient quality to make an accurate measurement of IMT or that suggested potentially significant carotid disease were reviewed by the consultant radiologist (P.L.A.) and a member of the study team. A decision was then made as to whether a rescan conducted by the consultant was necessary. Forty-one subjects had at least one of the variables recorded during the ultrasound examination later amended by the consultant.
Data Analysis
Information on the questionnaires and recording forms was checked by the clinic staff and entered onto a DBASE IV database. Error rates were determined by dual entry of all data, and reference was made to original records in cases with any discrepancy. Data files were transferred onto a Sun workstation for analysis using the SPSS statistical package.33 34
2 tests were used to test for differences in sex and social class between the initial sample examined at baseline and the subgroup examined at follow-up.
Values for IMT from the right and left sides of the neck were compared, and the final outcome variable, IMT, was calculated as the maximum of these two values and used throughout all subsequent analysis. Unlike the present study, previous reports have used the mean IMT value from the two sides, not the maximum.8 9 17 18 35 36 37 However, we consider that by using the side of the neck with the more advanced disease within each subject, we obtain a more realistic indicator as to the severity of the atherosclerosis. In particular, if the difference in the level of IMT between the two sides is large, the mean over both sides would generally underestimate the overall stage and clinical significance of the atherosclerosis. Twenty-seven participants (2.4%) had IMT for only one side of the neck recorded, and this value was taken as the maximum. Although such a small group would be very unlikely to bias inferences made concerning the entire sample, a t test to compare the mean IMT within this subgroup with that of the remainder of the population was nonsignificant (P=.489).
Because the distribution of IMT displayed a high level of positive skew, a logarithmic transformation of this variable was used in all tests that assume normality of the dependent variable, and geometric means are quoted when IMT values are compared between groups. The ABPI at follow-up was calculated for each leg by dividing the ankle pressure by the brachial pressure. In the analysis, the lower of these two values was used as a measure of disease severity. ANOVA was used to compare the distribution of IMT across categorical variables. ANCOVA was then used to conduct a similar analysis after adjustment for the confounding effects of age and sex. Multiple regression was used to assess the linear relationship between IMT and ABPI (as a continuous variable) both univariately and after adjustment for age and sex.
| Results |
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.005).
Of the 1156 subjects, 1106 (95.7%) had values for IMT recorded on at least one side of the neck. The geometric mean IMT for the whole study sample was 0.756 mm (n=1092) for the right CCA and 0.791 mm (n=1093) for the left. The values for IMT from the two sides showed strong statistical correlation (Pearson, .514; P
.01), which was almost identical when considering the sexes separately. However, a paired t test indicated that there was a statistically significant difference in IMT values between the right and left sides (P
.01). Among the1079 subjects with valid readings of IMT for both sides of the neck, 377 (34.9%) had greater IMT on the right, 477 (44.2%) had greater IMT on the left, and 225 (20.9%) had the same IMT on each side.
In the present study, men were found to have significantly higher IMT values than women in all 5-year age groups (Table 1
), although the difference reached statistical significance in the 65- to 69-year age group only (P
.05). After adjustment for age, the overall mean IMT was significantly higher in men than in women (P
.01).
|
The figure
shows box plots denoting the median and interquartile range of the distribution of IMT for each age group. These show a continuous increasing relationship of IMT with age group in both sexes. These values tended to be higher in men than women, suggesting that men aged 60 to 80 years were more likely to suffer from moderate to severe disease (defined as IMT >2 mm17 ). In both sexes, the distribution of IMT at younger ages was less skewed, and there was greater variance in men than women, suggesting that men were more susceptible to atherosclerotic development earlier in life. There was also greater variance in the distribution of IMT at older ages, particularly in men.
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Table 2
shows unadjusted and age- and sex-adjusted geometric means for IMT across selected levels of ABPI and presence of both intermittent claudication and coronary heart disease. ABPI was classified into two groups using the conventional 0.9 cutoff38 : subjects with an ABPI
0.9 had significantly higher IMT levels than those with an ABPI >0.9 (P
.01). The significance was not affected by adjustment for age and sex. The linear relationship between ABPI and IMT (log transformed) was assessed by multiple regression. After adjustment for age and sex, the probability value just failed to make statistical significance (P=.054), although the negative regression coefficient (b=-0.116, SE=0.06) suggested that the level of IMT was greater in individuals with lower ABPI. Subjects with a history of intermittent claudication showed significantly higher values of IMT than those without (P
.01), and the significance remained after adjustment for age and sex. Both the univariate and age- and sex-adjusted mean IMTs were higher in those subjects with coronary heart disease, although the differences were not statistically significant (P>.05).
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| Discussion |
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Some studies have reported difficulty in visualizing the far-wall intima-media boundary sufficiently to measure IMT. ARIC also postulated that IMTs in nonvisualized segments may differ from those that are visualized.16 However, visualization is mainly related to vessel depth and tortuosity, which are clearly not associated with IMT. With a visualization rate of 94.5% in the present study, which is similar to that in other reports, our data would appear to provide a good representation of the general population.
Table 3
compares study samples, measurement protocols, and distributional results from a selection of large epidemiological studies of ultrasonographically detected IMT. It illustrates consistency in the basic descriptive statistics between the four studies. As expected, values for IMT from both the KIHD35 and CHS18 were slightly higher than in ARIC16 or in the present study, since they measured IMT at the point of greatest thickness over the whole CCA. IMT in the KIHD was raised further as a result of the all-male sample taken from an area with extremely high incidence of ischemic heart disease. The sample in CHS was slightly older than in our study, possibly explaining the increased IMT. The clearest difference in the distribution of IMT between ARIC and our study was the presence of a larger number of older subjects (particularly men) with moderate to high IMT in the Edinburgh Artery Study, and there was less clustering around the mean value (greater variance). Again, this is partly explained by the different techniques for measurement of IMT.
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Interstudy variation in protocols for measurement of IMT affects the nature of the distribution of ultrasonographically measured IMT in these studies. B-mode scanning equipment (eg, manufacturer of scanning equipment, frequency of ultrasound used) also differed between studies, and such factors should be taken into account before any comparisons are drawn between results. Further epidemiological research involving B-mode ultrasound evaluation of IMT as a measure of carotid atherosclerosis would benefit from the standardization of both equipment and protocol for the measurement and recording of IMT.
Probably the strongest evidence to date as to the validity of IMT as a measure of atherosclerosis has been the consistent observation of strong relationships between the IMT and both cardiovascular risk factors and events.17 18 35 36 37 40 41 42 43 In particular, lifetime smoking and serum LDL cholesterol concentrations have consistently been found to be strongly related to IMT. A longitudinal study of Finnish men reported IMT as predictive of incident myocardial infarction43 and also found that the progression of IMT was predicted by smoking and blood lipid levels.36 ARIC reported an association between the distribution of ultrasonographically evaluated IMT and the known distribution of atherosclerosis, as reported by the multicenter International Atherosclerosis Project44 as evidence of the validity of this method.16 In addition, Pignoli et al2 found strong correlations between ultrasound and histological measurements from both atherosclerotic and disease-free carotid arteries.
This is one of the first studies to illustrate a strong relationship between previously validated indicators of peripheral arterial disease and CCA IMT. Those subjects with an ABPI
0.9 had a significantly higher age-sexadjusted IMT within the CCA than subjects with an ABPI >0.9. A linear regression analysis confirmed that low ABPI was associated with higher IMT. Furthermore, values of IMT for the 122 subjects with claudication were also found to be significantly higher than those of subjects without claudication. These findings are in accord with those of Bots et al,23 who found a negative relationship between IMT and ABPI in the Rotterdam Study. However, in the present study, the relationship between coronary heart disease and CCA IMT was not statistically significant.
We were somewhat surprised by the significance of the paired (within-subject) comparison of IMT on the left and right sides of the neck. Many more subjects (9.27% ) had greater IMT on the left side than on the right side of the neck (P
.01). This clearly suggested some tendency to greater thickening on the left side within our study. Review of the scanning procedure provided no simple explanation for a substantial inconsistency. The only other article, of which we are aware, to report an analogous finding was that from the European Carotid Surgery Trial, in which 55% of 1590 patients had symptomatic lesions located on the left side,45 a similar proportion to that reported here. There may be anatomic or hemodynamic explanations for increased IMT on the left side. Although investigation of this was not an objective of this study, further research to confirm (or refute) these findings would be beneficial.
The Figure
illustrates clear differences in the distribution of IMT both between age groups and between the sexes. In findings similar to those reported by ARIC,16 the prevalence of moderate to severe disease was greater in men than women at all ages, and each of the 25th, 50th, and 75th percentiles increased continuously across the four age groups for both sexes. The distribution of IMT for women was more closely centered around the mean, with fewer moderately high values (although similar extremes). This would suggest that men are more likely to be affected by moderate to severe disease and that low levels of carotid atherosclerosis develop at an earlier age in men. With regard to age, particularly evident in men was an increase in the variance (or spread) of the distribution in older subjects. This correlation between spread of IMT and age has also been reported by both Salonen and Salonen35 and ARIC.16
Because our data for IMT displayed a high level of positive skew, a logarithmic (log) transformation was used in any statistical tests that assumed a normally distributed dependent variable. Data for IMT from Finland35 was also positively skewed, but it was stated that a log transformation yielded results almost identical to those obtained using the untransformed IMT. In contrast, neither ARIC16 nor CHS18 reported any use of a log transformation of IMT, although Bots et al46 reported that the relationship between IMT measurement reproducibility and IMT disappeared after log transformation. For our data, all linear models using log(IMT) as the dependent variable accounted for more of the overall variance than the corresponding models with the untransformed variable, suggesting some nonlinearity in the relationship between IMT and age. This may be explained using the longitudinal analysis from Finland,36 in which the rate of progression of IMT was found to increase with age. This is in contrast with the CHS,18 which found no nonlinearity in the relationship between IMT and age, and a large study in Kentucky37 of patients with a history of smoking, which found lower levels of carotid plaque in subjects over 80 years than in those one to two decades younger. However, the latter study would have been particularly sensitive to a "healthy participant" effect, by which elderly subjects with high IMT were underrepresented because of early mortality. Salonen and Salonen36 estimated the annual increase in CCA IMT to be 0.06 mm/y, which was approximately six times greater than the estimates from the cross-sectional studies.16 18 However, this may be partly due to differences in measurement technique and loss of subjects with high IMT values.18 In the present study, we estimated average rates of progression of IMT as 0.012 mm/y in men and 0.010 mm/y in women, and the rates increased with advancing age.
This cross-sectional analysis of a representative population sample of subjects aged 60 to 80 years illustrates a strong association between IMT and both symptomatic and asymptomatic peripheral arterial disease. Men tended to experience mild atherosclerotic development earlier in life than women and were more likely to suffer from clinically significant intima-media thickening at older ages. Further longitudinal studies are required to investigate the nature of the progression of intima-media thickening with age and to standardize measurement techniques that would then permit accurate comparisons across studies.
| Selected Abbreviations and Acronyms |
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| Acknowledgments |
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Received August 13, 1996; revision received October 17, 1996; accepted October 17, 1996.
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R. A. Hegele, K. Z. Al-Shali, A. A. House, A. J.G. Hanley, S. B. Harris, M. Mamakeesick, A. Fenster, B. Zinman, H. Cao, and J. D. Spence Disparate Associations of a Functional Promoter Polymorphism in PCK1 With Carotid Wall Ultrasound Traits Stroke, December 1, 2005; 36(12): 2566 - 2570. [Abstract] [Full Text] [PDF] |
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S. Makita, M. Nakamura, and K. Hiramori The Association of C-Reactive Protein Levels With Carotid Intima-Media Complex Thickness and Plaque Formation in the General Population Stroke, October 1, 2005; 36(10): 2138 - 2142. [Abstract] [Full Text] [PDF] |
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M. Hintsanen, M. Kivimaki, M. Elovainio, L. Pulkki-Raback, P. Keskivaara, M. Juonala, O. T. Raitakari, and L. Keltikangas-Jarvinen Job Strain and Early Atherosclerosis: The Cardiovascular Risk in Young Finns Study Psychosom Med, September 1, 2005; 67(5): 740 - 747. [Abstract] [Full Text] [PDF] |
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D. N. Kiortsis, S. Tsouli, E. S. Lourida, V. Xydis, M. I. Argyropoulou, M. Elisaf, and A. D. Tselepis Lack of Association Between Carotid Intima-Media Thickness and PAF-Acetylhydrolase Mass and Activity in Patients with Primary Hyperlipidemia Angiology, July 1, 2005; 56(4): 451 - 458. [Abstract] [PDF] |
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M. M. McDermott, K. Liu, M. H. Criqui, K. Ruth, D. Goff, M. F. Saad, C. Wu, S. Homma, and A. R. Sharrett Ankle-Brachial Index and Subclinical Cardiac and Carotid Disease: The Multi-Ethnic Study of Atherosclerosis Am. J. Epidemiol., July 1, 2005; 162(1): 33 - 41. [Abstract] [Full Text] [PDF] |
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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] |
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A. Y.-M. Wang, S. S.-Y. Ho, M. Wang, E. K.-H. Liu, S. Ho, P. K.-T. Li, S.-F. Lui, and J. E. Sanderson Cardiac Valvular Calcification as a Marker of Atherosclerosis and Arterial Calcification in End-stage Renal Disease Arch Intern Med, February 14, 2005; 165(3): 327 - 332. [Abstract] [Full Text] [PDF] |
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M.L. Eigenbrodt, Z. Bursac, E.P. Eigenbrodt, D.J. Couper, R.E. Tracy, and J.L. Mehta Mathematical estimation of the potential effect of vascular remodelling/dilatation on B-mode ultrasound intima-medial thickness QJM, November 1, 2004; 97(11): 729 - 737. [Abstract] [Full Text] [PDF] |
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R. Elosua, J. M. Ordovas, L. A. Cupples, C. S. Fox, J. F. Polak, P. A. Wolf, R. A. D'Agostino Sr., and C. J. O'Donnell Association of APOE genotype with carotid atherosclerosis in men and women: the Framingham Heart Study J. Lipid Res., October 1, 2004; 45(10): 1868 - 1875. [Abstract] [Full Text] [PDF] |
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F. Orio Jr., S. Palomba, T. Cascella, B. De Simone, S. Di Biase, T. Russo, D. Labella, F. Zullo, G. Lombardi, and A. Colao Early Impairment of Endothelial Structure and Function in Young Normal-Weight Women with Polycystic Ovary Syndrome J. Clin. Endocrinol. Metab., September 1, 2004; 89(9): 4588 - 4593. [Abstract] [Full Text] [PDF] |
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J Ellul, P Talelli, G Terzis, A Chrysanthopoulou, G Gioldasis, and T Papapetropoulos Is the common carotid artery intima-media thickness associated with functional outcome after acute ischaemic stroke? J. Neurol. Neurosurg. Psychiatry, August 1, 2004; 75(8): 1197 - 1199. [Abstract] [Full Text] [PDF] |
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M. Zureik, S. Kony, C. Neukirch, D. Courbon, B. Leynaert, D. Vervloet, P. Ducimetiere, and F. Neukirch Bronchial Hyperresponsiveness to Methacholine Is Associated With Increased Common Carotid Intima-Media Thickness in Men Arterioscler. Thromb. Vasc. Biol., June 1, 2004; 24(6): 1098 - 1103. [Abstract] [Full Text] |
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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] |
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P. Poredos Intima-media thickness: indicator of cardiovascular risk and measure of the extent of atherosclerosis Vascular Medicine, February 1, 2004; 9(1): 46 - 54. [Abstract] [PDF] |
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M. L. Bots, G. W. Evans, W. A. Riley, and D. E. Grobbee Carotid Intima-Media Thickness Measurements in Intervention Studies: Design Options, Progression Rates, and Sample Size Considerations: A Point of View Stroke, December 1, 2003; 34(12): 2985 - 2994. [Abstract] [Full Text] [PDF] |
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O. T. Raitakari, M. Juonala, M. Kahonen, L. Taittonen, T. Laitinen, N. Maki-Torkko, M. J. Jarvisalo, M. Uhari, E. Jokinen, T. Ronnemaa, et al. Cardiovascular Risk Factors in Childhood and Carotid Artery Intima-Media Thickness in Adulthood: The Cardiovascular Risk in Young Finns Study JAMA, November 5, 2003; 290(17): 2277 - 2283. [Abstract] [Full Text] [PDF] |
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J. M. Murabito, J. C. Evans, M. G. Larson, K. Nieto, D. Levy, and P. W. F. Wilson The Ankle-Brachial Index in the Elderly and Risk of Stroke, Coronary Disease, and Death: The Framingham Study Arch Intern Med, September 8, 2003; 163(16): 1939 - 1942. [Abstract] [Full Text] [PDF] |
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T. J. Wang, B.-H. Nam, R. B. D'Agostino, P. A. Wolf, D. M. Lloyd-Jones, C. A. MacRae, P. W. Wilson, J. F. Polak, and C. J. O'Donnell Carotid Intima-Media Thickness Is Associated With Premature Parental Coronary Heart Disease: The Framingham Heart Study Circulation, August 5, 2003; 108(5): 572 - 576. [Abstract] [Full Text] [PDF] |
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D. N. O'Neal, G. Dragicevic, K. G. Rowley, M. Z. Ansari, N. Balazs, A. Jenkins, and J. D. Best A Cross-Sectional Study of the Effects of Type 2 Diabetes and Other Cardiovascular Risk Factors on Structure and Function of Nonstenotic Arteries of the Lower Limb Diabetes Care, January 1, 2003; 26(1): 199 - 205. [Abstract] [Full Text] [PDF] |
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M. Frick, S. P. Schwarzacher, H. F. Alber, A. Rinner, H. Ulmer, O. Pachinger, and F. Weidinger Morphologic rather than functional or mechanical sonographic parameters of the brachial artery are related to angiographically evident coronary atherosclerosis J. Am. Coll. Cardiol., November 20, 2002; 40(10): 1825 - 1830. [Abstract] [Full Text] [PDF] |
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G. J. Blake and P. M. Ridker C-Reactive Protein, Subclinical Atherosclerosis, and Risk of Cardiovascular Events Arterioscler. Thromb. Vasc. Biol., October 1, 2002; 22(10): 1512 - 1513. [Full Text] [PDF] |
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T. J. Wang, B.-H. Nam, P. W.F. Wilson, P. A. Wolf, D. Levy, J. F. Polak, R. B. D'Agostino, and C. J. O'Donnell Association of C-Reactive Protein With Carotid Atherosclerosis in Men and Women: The Framingham Heart Study Arterioscler. Thromb. Vasc. Biol., October 1, 2002; 22(10): 1662 - 1667. [Abstract] [Full Text] [PDF] |
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F. M. Raso, N. M. van Popele, M. A. D. H. Schalekamp, and T. J. M. van der Cammen Intima-Media Thickness of the Common Carotid Arteries Is Related to Coronary Atherosclerosis and left Ventricular Hypertrophy in Older Adults Angiology, September 1, 2002; 53(5): 569 - 574. [Abstract] [PDF] |
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K.-S. Cheng, D. P. Mikhailidis, G. Hamilton, and A. M. Seifalian A review of the carotid and femoral intima-media thickness as an indicator of the presence of peripheral vascular disease and cardiovascular risk factors Cardiovasc Res, June 1, 2002; 54(3): 528 - 538. [Abstract] [Full Text] [PDF] |
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R. F. Redberg, P. Greenland, V. Fuster, K. Pyorala, S. N. Blair, A. R. Folsom, A. B. Newman, D. H. O'Leary, T. J. Orchard, B. Psaty, et al. Prevention Conference VI: Diabetes and Cardiovascular Disease: Writing Group III: Risk Assessment in Persons With Diabetes Circulation, May 7, 2002; 105 (18): e144 - e152. [Full Text] [PDF] |
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L. Belhassen, C. Carville, G. Pelle, J. L. Monin, E. Teiger, A.-M. Duval-Moulin, P. Dupouy, J. L. Dubois Rande, and P. Gueret Evaluation of carotid artery and aortic intima-media thickness measurements for exclusion of significant coronary atherosclerosis in patients scheduled for heart valve surgery J. Am. Coll. Cardiol., April 3, 2002; 39(7): 1139 - 1144. [Abstract] [Full Text] [PDF] |
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L.M. Cupini, P. Pasqualetti, M. Diomedi, F. Vernieri, M. Silvestrini, B. Rizzato, F. Ferrante, and G. Bernardi Carotid Artery Intima-Media Thickness and Lacunar Versus Nonlacunar Infarcts Stroke, March 1, 2002; 33(3): 689 - 694. [Abstract] [Full Text] [PDF] |
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S Coccheri and G Palareti The cardiovascular risk burden of intermittent claudication Eur. Heart J. Suppl., March 1, 2002; 4(suppl_B): B46 - B49. [Abstract] [PDF] |
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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] |
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P. Amarenco Hypercholesterolemia, lipid-lowering agents, and the risk for brain infarction Neurology, September 1, 2001; 57(90002): S35 - 44. [Abstract] [Full Text] |
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N. Hosomi, K. Mizushige, H. Ohyama, T. Takahashi, M. Kitadai, Y. Hatanaka, H. Matsuo, M. Kohno, and J. A. Koziol Angiotensin-Converting Enzyme Inhibition With Enalapril Slows Progressive Intima-Media Thickening of the Common Carotid Artery in Patients With Non-Insulin-Dependent Diabetes Mellitus Stroke, July 1, 2001; 32(7): 1539 - 1545. [Abstract] [Full Text] [PDF] |
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S. Homma, N. Hirose, H. Ishida, T. Ishii, G. Araki, and J. H. Halsey Jr Carotid Plaque and Intima-Media Thickness Assessed by B-Mode Ultrasonography in Subjects Ranging From Young Adults to Centenarians Editorial Comment Stroke, April 1, 2001; 32(4): 830 - 835. [Abstract] [Full Text] [PDF] |
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P.M. Rothwell The Interrelation between carotid, femoral and coronary artery disease Eur. Heart J., January 1, 2001; 22(1): 11 - 14. [PDF] |
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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] |
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M. C. Whiteman, I. J. Deary, and F. G. R. Fowkes Personality and Social Predictors of Atherosclerotic Progression: Edinburgh Artery Study Psychosom Med, September 1, 2000; 62(5): 703 - 714. [Abstract] [Full Text] [PDF] |
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P.-J. Touboul, A. Elbaz, C. Koller, C. Lucas, V. Adrai, F. Chedru, P. Amarenco, and f. t. G. Investigators Common Carotid Artery Intima-Media Thickness and Brain Infarction : The Etude du Profil Genetique de l'Infarctus Cerebral (GENIC) Case-Control Study Circulation, July 18, 2000; 102(3): 313 - 318. [Abstract] [Full Text] [PDF] |
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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] |
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A.E Androulakis, G.K Andrikopoulos, D.J Richter, C.A Tentolouris, C.C Avgeropoulou, D.A Adamopoulos, P.K Toutouzas, A.G Trikas, C.I Stefanadis, and J.E Gialafos The role of carotid atherosclerosis in the distinction between ischaemic and non-ischaemic cardiomyopathy Eur. Heart J., June 1, 2000; 21(11): 919 - 926. [Abstract] [PDF] |
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M. Zureik, P. Ducimetiere, P.-J. Touboul, D. Courbon, C. Bonithon-Kopp, C. Berr, and C. Magne Common Carotid Intima-Media Thickness Predicts Occurrence of Carotid Atherosclerotic Plaques : Longitudinal Results From the Aging Vascular Study (EVA) Study Arterioscler. Thromb. Vasc. Biol., June 1, 2000; 20(6): 1622 - 1629. [Abstract] [Full Text] [PDF] |
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M. F. Muldoon, P. Nazzaro, K. Sutton-Tyrrell, and S. B. Manuck White-Coat Hypertension and Carotid Artery Atherosclerosis: A Matching Study Arch Intern Med, May 22, 2000; 160(10): 1507 - 1512. [Abstract] [Full Text] [PDF] |
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Y. Nagai, E J. Metter, and J. L Fleg Increased carotid artery intimal-medial thickness: risk factor for exercise-induced myocardial ischemia in asymptomatic older individuals Vascular Medicine, August 1, 1999; 4(3): 181 - 186. [Abstract] [PDF] |
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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] |
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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] |
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S. Rosfors, S. Hallerstam, K. Jensen-Urstad, M. Zetterling, and C. Carlstrom Relationship Between Intima-Media Thickness in the Common Carotid Artery and Atherosclerosis in the Carotid Bifurcation Stroke, July 1, 1998; 29(7): 1378 - 1382. [Abstract] [Full Text] [PDF] |
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A. J. Lee, P. I. Mowbray, G. D.O. Lowe, A. Rumley, F. G. R. Fowkes, and P. L. Allan Blood Viscosity and Elevated Carotid Intima-Media Thickness in Men and Women : The Edinburgh Artery Study Circulation, April 21, 1998; 97(15): 1467 - 1473. [Abstract] [Full Text] [PDF] |
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