Extracoronary atherosclerotic plaque at multiple sites and total coronary calcification deposit in asymptomatic men. Association with coronary risk profile

Maternal Phthalate and Bisphenol Urine Concentrations during Pregnancy and Early Markers of Arterial Health in Children

BACKGROUND

Fetal exposure to endocrine-disrupting chemicals such as phthalates and bisphenols might lead to fetal cardiovascular developmental adaptations and predispose individuals to cardiovascular disease in later life.

OBJECTIVES

We examined the associations of maternal urinary bisphenol and phthalate concentrations in pregnancy with offspring carotid intima-media thickness and distensibility at the age of 10 y.

METHODS

In a population-based, prospective cohort study of 935 mother-child pairs, we measured maternal urinary phthalate and bisphenol concentrations at each trimester. Later, we measured child carotid intima-media thickness and distensibility in the children at age 10 y using ultrasound.

RESULTS

Maternal urinary average or trimester-specific phthalate concentrations were not associated with child carotid intima-media thickness at age 10 y. Higher maternal average concentrations of total bisphenol, especially bisphenol A, were associated with a lower carotid intima-media thickness [differences -0.15 standard deviation score and 95% confidence interval (CI): -0.24, -0.09 and -0.13 (95% CI: -0.22, -0.04) per interquartile range (IQR) increase in maternal urinary total bisphenol and bisphenol A concentration]. Trimester-specific analysis showed that higher maternal third-trimester total bisphenol and bisphenol A concentrations were associated with lower child carotid intima-media thickness [differences -0.13 (95% CI: -0.22, -0.04) and -0.13 (95% CI: -0.22, -0.05) per IQR increase in maternal urinary bisphenol concentration]. Maternal urinary bisphenol or phthalate concentrations were not associated with child carotid distensibility.

DISCUSSION

In this large prospective cohort, higher maternal urinary bisphenols concentrations were associated with smaller childhood carotid intima-media thickness. Further studies are needed to replicate this association and to identify potential underlying mechanisms. https://doi.org/10.1289/EHP10293.

Arteriosclerosis, Atherosclerosis, and Cardiovascular Health: Joint Relations to the Incidence of Cardiovascular Disease

[Figure: see text].

Cardiovascular Risk Factors and Coronary Calcification in a Middle-aged Dutch Population: The ImaLife Study

PURPOSE

To assess the presence of coronary artery calcium (CAC) and its association with cardiovascular risk factors and Systematic COronary Risk Evaluation (SCORE) risk in a middle-aged Dutch population.

METHODS

Classic cardiovascular risk factors and CAC were analyzed in 4083 participants aged 45 to 60 years (57.9% women) from the population-based ImaLife study. CAC scores were quantified on noncontrast cardiac CT scans. Age-specific and sex-specific distribution of CAC categories (0, 1 to 99, 100 to 299, ≥300) and percentiles were determined. SCORE risk categories (<1%, ≥1% to 5%, and ≥5%) were compared with CAC distribution. Population attributable fractions (PAFs) of classic risk factors for CAC were estimated.

RESULTS

CAC was present in 54.5% male and 26.5% female participants. The percentage of individuals with CAC increased with increasing age. Mean SCORE was 2.0% in men and 0.7% in women. In SCORE <1%, 32.7% of men and 17.1% of women had CAC. In men with SCORE ≥5%, 26.9% had no CAC. Only 0.1% of women had SCORE ≥5%. PAF of classic risk factors for CAC was 18.5% in men and 31.4% in women. PAF was highest for hypertension (in men 8.0%, 95% confidence interval, 4.2%-11.8%; in women 13.1%, 95% confidence interval, 7.9%-18.2%) followed by hypercholesterolemia and obesity.

CONCLUSION

In this middle-aged cohort, more than half of the men and a quarter of the women had CAC. One out of 4 men at high risk (SCORE ≥5%) could be placed into a lower risk category owing to absence of CAC. Thus, adding CAC scoring to SCORE could have considerable effect on cardiovascular risk classification. Elimination of exposure to classic risk factors could reduce limited proportion of CAC in a middle-aged population.

Relationship between Smoking and Abdominal Aorta Calcification on Computed Tomography

Background

Cigarette smoking increases the risk of atherosclerosis, which often develops as vascular calcification on radiologic examinations. This study evaluated the relationship between smoking-related factors and incidental abdominal aorta calcification (AAC) detected by computed tomography (CT) among middle-aged and elderly men.

Methods

We assessed the abdominal CT findings of 218 men aged 40 to 81 years who underwent health check-ups. The associations between smoking factors and AAC were analyzed using logistic regression analysis to adjust for confounding variables such as age, lifestyle factors, and chronic diseases.

Results

Adjusting for confounding variables, the risk of AAC was significantly increased in association with smoking for at least 20 years (adjusted odds ratio [AOR], 5.22; 95% confidence interval [CI], 1.82–14.93), smoking 10+ pack-years (10–20 pack-years: AOR, 4.54; 95% CI, 1.07–5.68; >20 pack-years: AOR, 5.28; 95% CI, 2.10–13.31), and a history of smoking (former smoker: AOR, 2.10; 95% CI, 1.07–5.68; current smoker: AOR, 5.05; 95% CI, 2.08–12.26). In terms of the daily smoking amount, even a low smoking level increased the risk of AAC.

Conclusion

These findings suggest that smoking for 20+ years, smoking 10+ pack-years, and even a low level of smoking daily increases the likelihood of developing AAC. Clinicians should recommend that patients quit smoking and stress the importance of smoking duration when promoting health in middle-aged and elderly patients.

The association between heart rhythm complexity and the severity of abdominal aorta calcification in peritoneal dialysis patients

Abdominal aorta calcification (AAC) has been associated with clinical outcomes in peritoneal dialysis (PD) patients. Heart rhythm complexity analysis has been shown to be a promising tool to predict outcomes in patients with cardiovascular disease. In this study, we aimed to analyze the association between heart rhythm complexity and AAC in PD patients. We prospectively analyzed 133 PD patients. Heart rhythm complexity including detrended fluctuation analysis and multiscale entropy was performed. In linear analysis, the patients in the higher AAC group (AAC ≥15%) had a significantly lower standard deviation of normal RR intervals, very low frequency, low frequency, high frequency and low/high frequency ratio. In non-linear analysis, DFAα1, slope 1–5, scale 5 and area 6–20 were significantly lower in the patients with higher AAC. Receiver operating characteristic curve analysis showed that DFAα1 had the greatest discriminatory power to differentiate these two groups. Multivariate logistic regression analysis showed that DFAα1 and HbA1c were significantly associated with higher AAC ratio. Adding DFAα1 significantly improved the discriminatory power of the linear parameters in both net reclassification improvement and integrated discrimination improvement models. In conclusion, DFAα1 is highly associated with AAC and a potential cardiovascular marker in PD patients.

Assessment and relevance of carotid intima-media thickness (C-IMT) in primary and secondary cardiovascular prevention

Interventions aimed to prevent cardiovascular diseases (CVD) are more effective if administered to subjects carefully selected according to their CVD risk. Usually, this risk is evaluated on the basis of the presence and severity of conventional vascular risk factors (VRFs); however, atherosclerosis, the main pathologic substrate of CVD, is not directly revealed by VRFs. The measurement of the arterial wall, using imaging techniques, has increased the early identification of individuals prone to develop atherosclerosis and to quantify its changes over time.

B-mode ultrasound is a technique which allows a non-invasive assessment of the arterial wall of peripheral arteries (e.g. extracranial carotid arteries), and provides measures of the intima-media thickness complex (C-IMT) and additional data on the occurrence, localization and morphology of plaques.

Being an independent predictor of vascular events, C-IMT has been considered as a tool to optimize the estimation of CVD risk but this application is still a matter of debate. Though the technique is innocuous, relatively inexpensive and repeatable, its use in the clinical practice is limited by the lack of standardized protocols and clear guidelines.

This review outlines the rationale for the potential use of C-IMT in the stratification of cardio- and cerebro-vascular risk and discusses several topics related to the measurement of this variable, which are still controversial among experts of the field.

Factors associated with major cardiovascular events in patients with systemic necrotizing vasculitides: results of a longterm followup study

OBJECTIVE

Systemic necrotizing vasculitides (SNV) are associated with more frequent subclinical atherosclerosis, suggesting that SNV might be associated with a higher risk of major cardiovascular events (MCVE). We aimed to identify factors predictive of MCVE in patients with SNV.

METHODS

Patients in remission from SNV were assessed for CV risk factors and subclinical atherosclerosis. MCVE was defined as myocardial infarction, stroke, arterial revascularization, hospitalization for unstable angina, and/or death from CV causes. MCVE-free survival curves were compared using the log-rank test.

RESULTS

Forty-two patients were followed for 7.1±2.6 years. Eight patients (18.9%) had MCVE. The respective 5- and 10-year MCVE rates were 9.5% and 26.8%. National Cholesterol Education Program/Adult Treatment Panel III (NCEP/ATP III)-defined high-risk status [hazard ratio (HR) 5.02 (95% CI: 1.17-27.4), p=0.03], BMI>30 kg/m2 [HR 4.84 (95% CI: 1.46-116), p=0.02], and plaque detection in the abdominal aorta (p=0.01) were significantly associated with MCVE. SNV characteristics, corticosteroid maintenance therapy, and C-reactive protein>5 mg/l were not associated with MCVE. Plaque in the aorta was significantly associated with high-risk status (p<0.001), while BMI and high-risk status were independent variables. Thus, a BMI>30 kg/m2 and/or a high-risk status were strongly associated with MCVE (p=0.004). Carotid intima-media thickness (IMT) identified patients with early MCVE and was correlated with the time to MCVE (r2=0.68, p=0.01).

CONCLUSION

These results suggest that factors associated with a higher MCVE risk in patients with SNV are NCEP/ATP III-defined high-risk status and BMI>30 kg/m2. Carotid IMT could help identify patients with SNV at risk of early MCVE.

Association of abdominal aortic calcification with lifestyle and risk factors of cardiovascular disease

Background

Abdominal aortic calcification (AAC) is a marker of subclinical atherosclerotic disease and an independent predictor of subsequent vascular morbidity and mortality. This study was conducted to investigate the association of AAC with lifestyle and risk factors of cardiovascular disease.

Methods

The results of the abdominal computed tomography of 380 patients who visited Chungnam National University Hospital for a health checkup from January 1, 2008 to December 31, 2009 were reviewed. A six-point scale was used in grading the overall severity of the calcification in three areas of the abdominal aorta, including the area superior to the renal artery, the upper-half area inferior to the renal artery, and the lower-half area inferior to the renal artery, in addition to the common iliac artery. The association of the AAC severity with the age, lifestyle factors, and risk factors of cardiovascular disease was analyzed via multiple linear regression analysis.

Results

In the male subjects, the age, presence of dyslipidemia and smoking were positively related to AAC, but exercising was negatively related to AAC (total R² = 0.563). In the female subjects, the age and presence of diabetes mellitus, hypertension, and dyslipidemia were positively related to AAC, but exercising was negatively related to AAC (total R² = 0.547).

Conclusion

AAC was related to both the male and female subjects' age, presence of dyslipidemia, and exercising, to smoking in the male subjects and to the presence of diabetes mellitus and hypertension in the female subjects.

Diagnostic and prognostic value of low density lipoprotein-containing circulating immune complexes in atherosclerosis

Recently, it has been shown that increased level of LDL-containing circulating immune complexes (LDL-CIC) possess high diagnostic significance in clinically manifested atherosclerosis, but little is known about its diagnostic and prognostic significance in early atherosclerosis. Two-years prospective study was performed in 98 asymptomatic men aged 40-74. The rate of atherosclerosis progression was estimated by high-resolution B-mode ultrasonography as the increase in intima-media thickness (IMT) of common carotid arteries. The patients with elevated baseline levels of LDL-CIC were characterized by significantly higher levels of total and LDL cholesterol as well as significantly increased mean IMT of common carotid arteries. Among all baseline lipid parameters, only LDL-CIC and LDL cholesterol were contingent with the extent of early carotid atherosclerosis (p = 0.042 and p = 0.049, respectively) and had the highest levels of relative risk and odds ratio. During the follow up, significant IMT increase was registered in 53.1 % (n = 52) patients, IMT significant reduction was observed in 21.4 % (n = 21) patients. The increased levels of LDL-CIC, total serum cholesterol and LDL cholesterol had similar prognostic significance with the respect of atherosclerosis progression. The normal level of LDL-CIC (below than 16.0 μg/ml) was the only lipid parameter that predicted the absence of carotid atherosclerosis progression for two following years at prognostic value of 78.3 %. The results of the study allow assuming that LDL-CIC level may be employed not only as a marker of early atherosclerosis, but also has a sufficient prognostic value for clinical implications.

Carotid circumferential wall stress homeostasis in early remodeling: theoretical approach and clinical application

PURPOSE

To assess the influence of cardiovascular risk factors on arterial wall growth and the remodeling process.

METHODS

In a theoretical part, we used a well-established relationship linking the rate of thickening of the arterial wall to the circumferential wall stress (CWS) increase. In a clinical part, we measured the intima-media thickness (IMT) in 166 subjects with increased cardiovascular risk score but no treatment for hypertension or hypercholesterolemia, no diabetes, and no cardiovascular disease. Far wall IMT and lumen diameter were measured along the right carotid artery by high-resolution ultrasonography and computerized image analysis.

RESULTS

A decreasing linear relationship between IMT and CWS was deduced from the theoretical model, implying that an increase in CWS would result in an IMT increase, and that the higher the IMT-CWS slope, the higher the thickening response. Subjects with advanced age, renal insufficiency, high 10-year Framingham risk, carotid atherosclerosis, and advanced atherosclerosis at other sites had sharper IMT-CWS slope (p < 0.05), in agreement with the homeostasis of CWS hypothesis.

CONCLUSIONS

The IMT increase responding to a CWS increase was greater in high-risk patients.

Thematic series on the pathobiology of vascular calcification: an introduction

Vascular calcification increasingly afflicts our aging, dysmetabolic population. Once considered only a passive process of dead and dying cells, data from multiple laboratories worldwide have converged to demonstrate that vascular calcification is a highly regulated form of biomineralization. The goal of this thematic review series is to highlight what is known concerning the biological "players" and "game rules" with respect to vascular mineral metabolism. Armed with this understanding, it is hoped that novel therapeutic strategies can be crafted to prevent and treat vascular calcium accrual, to the benefit of our patients afflicted with arteriosclerotic valvular and vascular diseases.

Genetic mapping of vascular calcified plaque loci on chromosome 16p in European Americans from the diabetes heart study

A linkage peak for carotid artery calcified plaque (CarCP) on chromosome 16p (LOD 4.39 at 8.4 cM) in families with type 2 diabetes mellitus (T2DM) from the Diabetes Heart Study (DHS) has been refined. Fine mapping encompassed 104 single-nucleotide polymorphisms (SNPs) in 937 subjects from 315 families; including 45 SNPs in six candidate genes (CACNA1H, SEPX1, ABCA3, IL32, SOCS1, CLEC16A). Linkage and association analyses using variance components analysis adjusting for age, gender, body mass index (BMI), and diabetes status refined the CarCP linkage into two distinct peaks (LODs: 3.89 at 6.9 cM and 4.86 at 16.0 cM). Evidence of linkage for coronary calcified plaque (LOD: 2.27 at 19 cM) and a vascular calcification principle component (LOD: 3.71 at 16.0 cM) was also observed. The strongest evidence for association with CarCP was observed with SNPs in the A2BP1 gene region (rs4337300 P= 0.005) with modest evidence of association with SNPs in CACNA1H (P= 0.010-0.033). Bayesian quantitative trait nucleotide (BQTN) analysis identified a SNP, rs1358489, with either a functional effect on CarCP or in linkage disequilibrium (LD) with a functional SNP. This study refined the 16p region contributing to vascular calcification. The causal variants remain to be identified, but results are consistent with a linkage peak that is due to multiple common variants, though rare variants cannot be excluded.

Subclinical atherosclerosis modeling: Integration of coronary artery calcium score to Framingham equation

Medical prevention consists to identify as soon as possible apparently healthy individuals who develop a disease and to engage them for active preventive treatment. Several cross-sectional studies of general populations or high cardiovascular risk have shown that coronary calcium score (coronary artery calcium, CAC) was positively associated with traditional risk factors (hypertension, dyslipidemia, diabetes, and smoking) and some new risk factors (fibrinogen). In this work, we first calculated, among 618 men, the risk of 10-years cardiovascular heart disease (CHD) according to the Framingham risk model, and then we calculated the probability that the CAC score of an individual falls in all four CAC categories (0, 1-100, 101-400 and > 400). We obtained risk factors adjusted relative risk (RR) estimates from a meta-analysis comparing the risk of coronary heart disease in individuals with CAC scores of 1-100 (RR = 1.7), 101 - 400 (RR = 3.0) and > 400 (RR = 4.3) with the risk of a person with a CAC score zero. The new model for the risk of CHD for each CAC score category were then calculated assuming an average 1-year risk of CHD and risk assessment of the four CAC score categories, weighted by the probability that scores fall into each category. The combination of modeling the CCA with the modeling of conventional risk factors allows obtaining a remarkable predictive value that can improve the assessment of overall risk Framingham through the reclassification of the risk of CHD to an extent which may be clinically important.

Smoking induces long-lasting effects through a monoamine-oxidase epigenetic regulation

BACKGROUND

Postulating that serotonin (5-HT), released from smoking-activated platelets could be involved in smoking-induced vascular modifications, we studied its catabolism in a series of 115 men distributed as current smokers (S), never smokers (NS) and former smokers (FS) who had stopped smoking for a mean of 13 years.

METHODOLOGY/PRINCIPAL FINDINGS

5-HT, monoamine oxidase (MAO-B) activities and amounts were measured in platelets, and 5-hydroxyindolacetic acid (5-HIAA)--the 5-HT/MAO catabolite--in plasma samples. Both platelet 5-HT and plasma 5-HIAA levels were correlated with the 10-year cardiovascular Framingham relative risk (P<0.01), but these correlations became non-significant after adjustment for smoking status, underlining that the determining risk factor among those taken into account in the Framingham risk calculation was smoking. Surprisingly, the platelet 5-HT content was similar in S and NS but lower in FS with a parallel higher plasma level of 5-HIAA in FS. This was unforeseen since MAO-B activity was inhibited during smoking (P<0.00001). It was, however, consistent with a higher enzyme protein concentration found in S and FS than in NS (P<0.001). It thus appears that MAO inhibition during smoking was compensated by a higher synthesis. To investigate the persistent increase in MAO-B protein concentration, a study of the methylation of its gene promoter was undertaken in a small supplementary cohort of similar subjects. We found that the methylation frequency of the MAOB gene promoter was markedly lower (P<0.0001) for S and FS vs. NS due to cigarette smoke-induced increase of nucleic acid demethylase activity.

CONCLUSIONS/SIGNIFICANCE

This is one of the first reports that smoking induces an epigenetic modification. A better understanding of the epigenome may help to further elucidate the physiopathology and the development of new therapeutic approaches to tobacco addiction. The results could have a larger impact than cardiovascular damage, considering that MAO-dependent 5-HT catabolism is also involved in addiction, predisposition to cancer, behaviour and mental health.

Prediction of coronary artery disease by a systemic atherosclerosis score index derived from whole-body MR angiography

BACKGROUND

Whole-body magnetic resonance angiography (WB-MRA) has shown its potential for the non-invasive assessment of nearly the entire arterial vasculature within one examination. Since the presence of extra-cardiac atherosclerosis is associated with an increased risk of coronary events, our goal was to establish the relationship between WB-MRA findings, including a systemic atherosclerosis score index, and the presence of significant coronary artery disease (CAD).

METHODS

WB-MRA was performed on a 1.5T scanner in 50 patients scheduled to undergo elective cardiac catheterization for suspected CAD. In each patient, 40 extra-cardiac vessel segments were evaluated and assigned scores according to their luminal narrowing. The atherosclerosis score index (ASI) was generated as the ratio of summed scores to analyzable segments.

RESULTS

ASI was higher in patients with significant (> 50% stenosis) CAD (n = 27) vs. patients without CAD (n = 22; 1.56 vs. 1.28, p = 0.004). ASI correlated with PROCAM (R = 0.57, p < 0.001) and Framingham (R = 0.36, p = 0.01) risk scores as estimates of the 10-year risk of coronary events. A ROC derived ASI of > 1.54 predicted significant CAD with a sensitivity of 59%, specificity of 86% and a positive predictive value of 84%. Logistic regression revealed ASI > 1.54 as the strongest independent predictor for CAD with a 11-fold increase in likelihood to suffer from significant coronary disease. On the contrary, while 15/27 (55%) of patients with CAD exhibited at least one extra-cardiac stenosis > 50%, only 3/22 (14%) of those patients without CAD did (p = 0.003). The likelihood for an extra-cardiac stenosis when CAD is present differed between vascular territories and ranged from 15% for a carotid stenosis to 44% for a stenosis in the lower extremities.

CONCLUSION

This study provides important new evidence for the close association of extra-cardiac and coronary atherosclerosis. The novel findings that a WB-MRA derived systemic atherosclerosis score index is not only associated with established cardiovascular risk scores but is also predictive of significant CAD suggest its potential prognostic implications and underline the importance to screen for coronary disease in patients with extra-cardiac manifestations of atherosclerosis.

Prevalence of coronary artery disease across the Framingham risk categories: coronary artery calcium scoring and MSCT coronary angiography

BACKGROUND

Non-invasive assessment of subclinical atherosclerosis by means of coronary artery calcium scoring (CACS) and multi-slice computed tomography (MSCT) coronary angiography could improve patients' risk stratification. However, data relating observations on CACS and MSCT coronary angiography to traditional risk assessment are scarce.

METHODS AND RESULTS

In 314 consecutive outpatients (54 +/- 13 years, 56% males) without known CAD, CACS and 64-slice MSCT coronary angiography were performed. According to the Framingham risk score (FRS), 51% of patients were at low, 24% at intermediate and 25% at high risk, respectively. MSCT angiograms showing atherosclerosis were classified as showing obstructive (> or =50% luminal narrowing) CAD or not. Both CACS and MSCT coronary angiography showed a high prevalence of normal coronary arteries in low FRS patients (70% and 61%, respectively). An increase in the prevalence of CACS >400 (4% low vs 19% intermediate vs 36% high), CAD (39% low vs 79% intermediate vs 91% high), and obstructive CAD (15% low vs 43% intermediate vs 58% high) was observed across the FRS categories (P < .0001 for all comparisons).

CONCLUSIONS

A strong positive relationship exists between FRS and the prevalence and extent of atherosclerosis. Especially in intermediate FRS patients, CACS and MSCT coronary angiography provide useful information on the presence of subclinical atherosclerosis.

Prospective evaluation of the role of atherosclerosis on cerebral atrophy: pilot study

PURPOSE

Our purpose was to study the association between atherosclerosis measured by arterial calcium on computed tomography (CT) and cerebral atrophy demonstrated by brain magnetic resonance imaging (MRI).

MATERIALS AND METHODS

IRB approved this prospective study. Twenty-one consecutive patients with acute stroke-like symptoms who are scheduled to have brain MRI were recruited on a voluntary basis. electrocardiogram (ECG)-gated helical CT scans were used to determine the arterial calcium as a reliable index of underlying atherosclerosis. Extracranial arterial calcium content was measured quantitatively by special software available in our CT scanner. Intracranial calcium was graded qualitatively. Brain MRI was independently evaluated to identify cortical, central atrophy, and ischemic changes. Relationship between CT demonstrated atherosclerosis and cerebral ischemic changes, brain atrophy patterns were evaluated both without and with adjustment for age and hypertension.

RESULTS

Out of 21 patients 20 were included in final study group. There was no correlation between atherosclerotic calcium measures and cortical atrophy, ischemic findings. Both intracranial and extracranial atherosclerosis had partial correlation with central atrophy (R= 0.43 and 0.52, respectively). After adjustment for age, only intracranial atherosclerosis maintained a partial correlation with central atrophy (R= 0.41). However, this correlation did not reach a statistically significant level (P= .10).

CONCLUSIONS

Intracranial atherosclerosis demonstrated a possible correlation with central atrophy.

Assessment of subclinical atherosclerosis and cardiovascular risk

Conventional cardiac risk factors do not fully explain the incidence of coronary artery disease and coronary events. Risk stratification and therapy based solely on these conventional risk factors may exclude a population who would otherwise benefit from lifestyle and risk factor modification. Recent efforts to improve our ability to recognize individuals and populations at increased risk of coronary events have focused on the noninvasive imaging of atherosclerosis, both in coronary and extracoronary arterial beds, or the identification of "non-traditional" serum markers. We review the complimentary role of these newer methods of risk stratification in the context of conventional risk factor evaluation.

Is intracranial atherosclerosis an independent risk factor for cerebral atrophy? A retrospective evaluation

Background

Our purpose was to study the association between the intracranial atherosclerosis as measured by cavernous carotid artery calcification (ICAC) observed on head CT and atrophic changes of supra-tentorial brain demonstrated by MRI.

Methods

Institutional review board approval was obtained for this retrospective study incorporating 65 consecutive patients presenting acutely who had both head CT and MRI. Arterial calcifications of the intracranial cavernous carotids (ICAC) were assigned a number (1 to 4) in the bone window images from CT scans. These 4 groups were then combined into high (grades 3 and 4) and low calcium (grades 1 and 2) subgroups. Brain MRI was independently evaluated to identify cortical and central atrophy. Demographics and cardiovascular risk factors were evaluated in subjects with high and low ICAC. Relationship between CT demonstrated ICAC and brain atrophy patterns were evaluated both without and with adjustment for cerebral ischemic scores and cardiovascular risk factors.

Results

Forty-six of the 65 (71%) patients had high ICAC on head CT. Subjects with high ICAC were older, and had higher prevalence of hypertension, diabetes, coronary artery disease (CAD), atrial fibrillation and history of previous stroke (CVA) compared to those with low ICAC. Age demonstrated strong correlation with both supratentorial atrophy patterns. There was no correlation between ICAC and cortical atrophy. There was correlation however between central atrophy and ICAC. This persisted even after adjustment for age.

Conclusion

Age is the most important determinant of atrophic cerebral changes. However, high ICAC demonstrated age independent association with central atrophy.

Genetic epidemiology of subclinical cardiovascular disease in the diabetes heart study

A genome-wide linkage scan of 357 European American (EA) and 72 African American (AA) pedigrees multiplex for type 2 diabetes mellitus (T2DM) was performed with multipoint nonparametric QTL linkage analysis. Four subclinical measures of cardiovascular disease (CVD): coronary artery (CCP), carotid artery (CarCP), and abdominal aortic calcified plaque (AACP) and carotid artery intima-media thickness (IMT) were mapped. Analyses were adjusted for age, gender, body mass index, and (if appropriate) ethnicity and diabetes status. Evidence for linkage was observed in EA T2DM subjects to CarCP near 16p13 (LOD=4.39 at 8.4 cM; P = 0.00001). When all EA subjects were included, the LOD score was 2.52, suggesting an amplification of the linkage by diabetes. Linkage analysis of a principal components measure of vascular calcium (LOD = 3.85 at 9.3 cM on 16p in EA T2DM subjects) and bivariate analysis of CarCP X IMT (LOD = 3.77 at 9.3 cM on 16p in EA T2DM subjects) were consistent with this linkage. In addition, evidence for linkage was observed with CCP near D15S1515 (LOD = 2.34) in EAs. Additional loci on chromosomes 1, 2, 7, 10, 13, and 21 had LODs > 2.0. The identification of trait-determining polymorphisms underlying these linkages will help delineate risk factors for CVD in T2DM and the general population.

Smoking, smoking cessation and aortic arch calcification in older Chinese: the Guangzhou Biobank Cohort Study

OBJECTIVE

To study the association between smoking, smoking cessation and aortic arc calcification (AAC) in an older Chinese population.

METHODS

A total of 3022 men and 7279 women aged 50-85 years were recruited and received a medical check-up including measurement of fasting plasma vascular risk factors. Two radiologists reviewed the posterior-anterior plain chest X-ray radiographs and assessed AAC together. Information on smoking status, socioeconomic and lifestyle factors was collected.

RESULTS

The crude prevalence of AAC in men (38.58%) was lower than that in women (41.37%). The adjusted odds ratios of AAC increased significantly across never, ex- and current smokers in both genders. Dose-response relationships were observed among current smokers for smoking amount (cigarettes/day), smoking duration (years) and cigarette pack-years in both genders (all p<0.01). The odds ratios decreased significantly (p=0.018) with longer duration of quitting in light ex-smoking men (<23.5 pack-years) but showed no beneficial effect (p=0.72) for heavy ex-smokers (>or=23.5 pack-years).

CONCLUSION

Smoking increased the risk of AAC in Chinese, while smoking cessation decreased the risk only in male light ex-smokers. Chest X-ray is a cheap and simple method to detect AAC, which should be an important warning signal for immediate smoking cessation.

Whole-body screening of atherosclerosis with magnetic resonance angiography

With whole-body magnetic resonance angiography (WBMRA), it is possible to examine the whole arterial tree except intracranial and coronary vessels in a single examination without the risks involved in ionizing radiation or arterial cannulation. Whole-body magnetic resonance angiography is well suited for repeated clinical examinations in patients with systemic diseases such as vasculitis or atherosclerosis and can also be used for scientific purposes. On the basis of the WBMRA overview, a possible further development of the WBMRA concept can be to perform further acquisitions at sites with atherosclerotic plaques with higher-resolution scans to determine the degree of stenosis more accurately or to achieve plaque characterization. A total validation of WBMRA compared with digital subtraction angiography (DSA) is not possible owing to the hazards of ionizing radiation. Studies have shown a high sensitivity and specificity for the pelvic and lower limb arteries in comparison with DSA. No systematic validation against DSA has been performed for the renal, aortic, and carotid arteries. Various methods have been used, however, for confirmation of vascular abnormalities found on WBMRA such as ultrasonography, dedicated MRA, or DSA, with reasonably high agreement. The WBMRA method has not been studied with regard to prediction of future cardiovascular (CV) events, as have intima media thickness, coronary artery calcium scoring, and the ankle-brachial index. The full usefulness of WBMRA in an epidemiological setting and as a complementary screening tool for assessing CV risk still needs to be validated against future CV events.

Association between arterial pressure and coronary artery calcification

OBJECTIVES

Coronary artery calcification (CAC) determined by electron beam computed tomography is a predictor of future cardiovascular events. This study investigates conditions affecting CAC severity in patients with coronary artery disease (CAD) undergoing coronary angiography.

METHODS

Presence and degree of CAC were assessed angiographically in 877 CAD patients grouped into no visible CAC (n = 333), mild to moderate CAC (n = 321), and severe CAC (n = 223). Regression analyses investigated relationships between CAC and demographic data, cardiovascular risk factors, and coronary anatomy.

RESULTS

Prevalences of hypertension and systolic blood pressure (SBP) values were higher in individuals with CAC (moderate CAC: 49.5%, 137.5 +/- 18.6 mmHg; severe CAC: 58.3%, 142.1 +/- 20.4 mmHg) compared to individuals with CAD but no CAC (42.0%, 134.0 +/- 18.4 mmHg; both P < 0.001). Likewise, pulse pressure was significantly elevated with increasing degree of CAC (no CAC, 52.3 +/- 13.6 mmHg vs moderate CAC, 55.7 +/- 14.4 mmHg vs severe CAC, 59.1 +/- 15.4 mmHg; P < 0.001). Further determinants of CAC were age, positive family history for CAC and severity of CAD. No differences in CAC severity were found in relation to body mass index, low-density lipoprotein-cholesterol, diabetes, and smoking habits. In multivariate analysis, CAC was independently related to age, SBP or pulse pressure, respectively, positive family history for CAC, and the severity of CAD.

CONCLUSIONS

Of the cardiovascular risk factors, SBP and pulse pressure display the strongest relationship with angiographic detection of CAC. Mechanistic studies need to clarify whether hypertension causes CAC, or whether coronary calcium deposition serves as a marker for a higher degree of vascular calcification and, thus, impaired vascular compliance and higher blood pressure levels.

Does atherosclerotic aortic plaque detected by telecardiography indicate an increased risk of coronary artery disease?

OBJECTIVE

The purpose of this study was to determine the cause of aortic arch calcification and to evaluate its prognostic value as an indicator of cardiovascular disease and its severity.

METHODS AND RESULTS

The study was conducted prospectively among 1027 patients who underwent a coronary angiography in our hospital between April 2002 and September 2002 for suspected coronary artery disease. All chest x-rays were reviewed by a radiologist, who categorized aortic arch calcifications by their presence or absence. The patients were stratified according to age (< or =50, 51-64, and > or =65 years) to eliminate the influence of age on aortic arch calcification. Coronary lesions were considered either single-vessel or multivessel disease. Univariate analysis revealed significant correlation with age (r = 0.37; P < .001), presence of hypertension (r = 0.14; P < .001), smoking (r = -0.10; P = .001), presence of coronary artery disease (r = 0.10; P = .001), and the existence of multi-vessel disease (r = 0.09; P = .006). Multivariate analysis disclosed significant association with age and hypertension and no association with smoking, coronary artery disease, and other risk factors.

CONCLUSION

The aortic arch calcifications observed on plain chest x-rays are usually age related, and both aortic arch calcifications and coronary artery disease are strongly associated with age. The presence of aortic calcification on chest x-rays was not an indicator of the presence and extent of coronary artery disease.

Antioxidant Vitamin Intake and Subclinical Coronary Atherosclerosis

Numerous studies have evaluated the association between antioxidants and coronary atherosclerosis but have been limited by its study among individuals with advanced atherosclerosis. The authors studied 865 consecutive patients, 39-45 years of age, without known coronary artery disease and presenting for a periodic physical examination. Antioxidant intake was assessed with the Block Dietary Questionnaire, and coronary atherosclerosis was identified by measuring coronary artery calcification using electron beam computed tomography. The mean age was 42 (+/-2), 83% were male, and the prevalence of coronary artery calcification was 20%. Vitamin supplements were used by 56% of the participants, and the mean (+/-SD) daily intake (dietary plus supplemental) of vitamins A, C, and E were 1683 mg (+/-1245), 371 mg (+/-375), and 97 mg (+/-165), respectively. There was no significant correlation between coronary artery calcification score and individual vitamin or total antioxidant vitamin intake, even after adjusting for traditional cardiac risk factors. The highest quartile of vitamin E was positively associated with calcification (odds ratio=1.77; 95% confidence interval, 1.02-3.06). Antioxidant vitamin intake is not significantly related to coronary artery calcification, implying that there is no effect on the development of early coronary atherosclerosis. High doses of vitamin E may confer an increased risk of calcified atherosclerosis.

Association of alpha2-Heremans-Schmid glycoprotein polymorphisms with subclinical atherosclerosis

CONTEXT

Cardiovascular disease is significantly increased in individuals with type 2 diabetes mellitus (T2DM), especially in the presence of calcified atherosclerotic plaque. Fetuin A is an important mineralization inhibitor, and polymorphisms in the corresponding alpha2-Heremans-Schmid glycoprotein (AHSG) gene have been shown to be associated with serum fetuin A levels and free phosphate levels, as well as cardiovascular disease death.

OBJECTIVE

This study investigated whether polymorphisms in AHSG contribute to the development of calcified atherosclerotic plaque in the coronary and carotid arteries and to carotid artery intima-media thickness.

DESIGN

Eleven single nucleotide polymorphisms (SNPs) in AHSG were genotyped and evaluated for association with quantitative measures of subclinical atherosclerosis.

PARTICIPANTS

Subjects were 829 T2DM-affected European Americans from 368 families in the Diabetes Heart Study.

MAIN OUTCOME MEASURES

Participants were phenotyped for cardiovascular risk factors and atherosclerosis traits. The extent of coronary artery calcified plaque (CorCP) and carotid artery calcified plaque (CarCP) was measured using quantitative computed tomography, and carotid artery intima-media thickness was measured using high-resolution B mode ultrasonography.

RESULTS

Four SNPs in AHSG were nominally associated with CorCP in European Americans with T2DM (P < 0.05). Two 3-SNP haplotypes in the exon 6-7 region were associated with CorCP in European Americans with T2DM (P < 0.06).

CONCLUSIONS

Sequence variants in the AHSG gene affect the extent of CorCP in T2DM-affected European Americans, consistent with the known biological role of AHSG in vascular calcification. These data implicate AHSG in the development of vascular calcified plaque in diabetic subjects.

Clinical significance of aortic knob width and calcification in unstable angina

BACKGROUND

Chest radiography is a routine examination evaluating those patients with chest pain. There are few data about the correlation between aortic knob width, calcification and coronary atherosclerosis.

METHODS AND RESULTS

The aortic knob width was measured and the presence of aortic knob calcification was assessed via a chest posteroanterior view in 178 consecutive patients. The aortic knob width and calcification were compared to the risk factor and the extent of coronary artery disease. Patient's age (69.5+/-7.95 vs 61.1+/-10.29 years, p=0.010), the prevalence of hypertension (65.9 vs 46.3%, p=0.024) and diabetes (43.2 vs 26.1%, p=0.033), the level of total cholesterol (196.8+/-63.21 vs 188.6+/-44.45 mg/dl, p=0.049) and the incidence of multi-vessel disease (65.9 vs 38.1%, p<0.001) were higher in patients with aortic knob calcification than in patients without calcification. The aortic knob width and the prevalence of aortic knob calcification were significantly correlated with the severity of coronary artery disease. Multivariate analysis demonstrated that aortic knob calcification and diabetes were independent factors for multi-vessel disease (p=0.018 and p=0.012).

CONCLUSIONS

The observation of aortic knob on a chest radiograph can provide important predictive information of coronary atherosclerosis.

Intracranial carotid artery calcification on head CT and its association with ischemic changes on brain MRI in patients presenting with stroke-like symptoms: retrospective analysis

INTRODUCTION

Our purpose was to study the association between the intracranial arterial calcifications observed on head CT and brain infarcts demonstrated by MRI in patients presenting with acute stroke symptoms.

METHODS

Institutional review board approval was obtained for this retrospective study which included 65 consecutive patients presenting acutely who had both head CT and MRI. Arterial calcifications of the vertebrobasilar system and the intracranial cavernous carotid arteries (intracranial carotid artery calcification, ICAC) were assigned a number (1 to 4) in the bone window images from CT scans. These four groups were then combined into high calcium (grades 3 and 4) and low calcium (grades 1 and 2) subgroups. Brain MRI was independently evaluated to identify acute and chronic large-vessel infarcts (LVI) and small-vessel infarcts (SVI). The relationship between ICAC and infarcts was evaluated before and after adjusting for demographics and cardiovascular risk factors.

RESULTS

Statistical analysis could not be performed for the vertebrobasilar system due to an insufficient number of patients in the high calcium group. Of the 65 patients, 46 (71%) had a high ICAC grade on head CT. They were older and had a higher prevalence of cardiovascular risk factors. Acute SVI (P = 0.006), chronic SVI (P = 0.006) and acute LVI (P = 0.04) were associated with a high ICAC grade. After adjustment for age and other risk factors, only acute SVI was associated with a high ICAC grade (P = 0.002).

CONCLUSION

Although age emerged as the most important determinant of ischemic cerebral changes, there were rather complex interactions among multiple risk factors with different infarct types. A high ICAC grade demonstrated a correlation with acute SVI in our patients independent of these risk factors.

Increased prevalence of subclinical atherosclerosis in patients with small-vessel vasculitis

BACKGROUND AND OBJECTIVE

Although changes in smaller vessels is the hallmark of medium-sized and small-vessel vasculitis, it has been suggested that large arteries of such patients may also be affected by the early atherosclerotic process because of coexisting risk factors or systemic inflammation. This study aimed to bring additional arguments supporting this hypothesis.

DESIGN, SETTING AND PATIENTS

50 consecutive patients with primary systemic necrotising vasculitis and 100 controls matched for age and sex underwent ultrasonic detection of plaque in three peripheral vessels (carotid and femoral arteries and abdominal aorta). Cardiovascular risk factors and inflammation (C reactive protein (CRP)) were concomitantly measured in all participants, and diagnosis of high-risk status was defined by the presence of known history of cardiovascular disease, type 2 diabetes or 10-year-Framingham Risk Score > or =20%.

RESULTS

Patients had higher frequency of plaque than controls in the carotid arteries (p<0.05), in the aorta (p<0.01) and in the three vessels examined (p<0.001), and adjustment for high-risk status did not confound such difference in the aorta and in the three vessels. In the overall population of patients and controls, vasculitis was associated with a higher frequency of three-vessel plaques (p<0.05), independently of high-risk status and CRP. In patients, the higher frequency of three-vessel plaques was associated with high-risk status (p<0.05) but not with CRP, or disease and treatment characteristics.

CONCLUSIONS

Small-vessel vasculitis is associated with more frequent subclinical atherosclerosis, especially extended to multiple peripheral vessels, and such association is not entirely explained by cardiovascular risk factors and systemic inflammation.

Decreased number of circulating CD34+KDR+ cells in asymptomatic subjects with preclinical atherosclerosis

OBJECTIVES

To assess whether circulating endothelial progenitor cells (CEPCs) can be considered as a cardiovascular risk marker before event has occurred, that is less firmly established than in clinically overt atherosclerosis.

METHODS

Number of CD34+KDR+ cell number per ml blood was measured by flow cytometry in 84 untreated subjects without cardiovascular disease. Atherosclerotic plaque was detected by ultrasound in carotid, abdominal aortic and femoral sites and the number of sites affected by plaque among these three sites was counted as 0, 1, 2 or 3. Additionally, intima-media thickness (IMT) was measured by computerized ultrasound imaging of both common carotid segments.

RESULTS

CD34+KDR+ cell number decreased by 48, 29 or 30% in the presence of carotid, aortic or femoral plaque (p<0.001, 0.05, 0.05, respectively) as compared to the absence of plaque and by 70% in the presence of three sites affected with plaque as compared with 0 site with plaque (p<0.01) but did not change with increasing IMT tertiles. Adjustment for Framingham risk score, that was also associated with decreased CD34+KDR+ cell number (p<0.001), made CD34+KDR+ cell number associations with plaque insignificant, except at the carotid site (p<0.01).

CONCLUSIONS

Reduced CEPC number may participate to preclinical stage of atherosclerosis and provide additional information to traditional risk factors as regards global risk assessment.

Prognostic value of coronary artery calcium screening in asymptomatic smokers and non-smokers

AIMS

To determine the extent and prognostic significance of coronary artery calcium in asymptomatic smokers and non-smokers. Population data are available on the prognostic impact of smoking on atherosclerotic imaging measurements of the carotid and peripheral arteries. Limited data are available on the impact of cigarette smoking on the prognostic value of coronary calcium.

METHODS AND RESULTS

A referred patient registry of 10,377 asymptomatic individuals (40% were current smokers) was followed for death from all-causes at 5 years. Univariable and multivariable Cox proportional hazard models were calculated to estimate time to all-cause mortality. Cumulative 5-year survival was 96.9 and 98.4% for smokers when compared with non-smokers (P < 0.0001). Using a stratified Cox proportional hazards survival analysis, survival for non-smokers ranged from 99.7 to 89.6% with calcium score of 0-10 and >1000 (P < 0.0001). In comparison, smokers had survival rates ranging from 99.5 to 81.4% for calcium score of 0-10 to >1000 (P < 0.0001). When further evaluating the effect of age on prognosis by coronary calcium, there was an additive relationship between age and calcium that was exacerbated with smoking, resulting in higher relative risk ratios for older smokers with coronary calcium (P < 0.0001). For smokers <50 years of age, a calcium score >1000 was associated with a relative risk ratio that was elevated 8.9-fold (P = 0.029). Thus, resulting in an expected reduction in life expectancy of 4.8 years for smokers <50 years of age with a calcium score >400 (P < 0.0001).

CONCLUSION

The prognostic value of coronary artery calcium scoring was accurate in identifying a high-risk cohort of asymptomatic smokers and non-smokers. Young smokers with high-risk calcium scores have a four- to nine-fold increased risk of dying when compared with similarly aged non-smokers. When prospectively applied, evidence of a high-risk calcium score may be useful in educating patients as to their expected risk of dying over the next 5 years.

Current possibilities for detecting high risk of cardiovascular disease

Current possibilities for better detecting high risk of coronary heart disease (CHD) and stroke and peripheral arterial disease are described in this review. A first step is based on risk factors assessment that allows establishing high-risk diagnostic, either by detecting a condition termed as "CHD risk equivalent" and defined by one or more severe major risk factor, or by calculating multifactorial risk in asymptomatic subjects with a global risk score integrating several moderate risk factors. A second diagnostic step, concerning subjects not considered at high-risk by risk factors assessment, is based on non-invasive detection of sub clinical atherosclerosis via a wide variety of structural and functional arterial markers. A third step focuses on detection of myocardial ischemia that may add diagnostic and prognostic information in subjects with high CHD risk. The implementation of high-risk strategy is not yet standardized but it should allow improving cost-effectiveness of cardiovascular prevention, particularly in asymptomatic subjects.

May subclinical arterial disease help to better detect and treat high-risk asymptomatic individuals?

The diagnosis of high risk of cardiovascular disease (CVD) in subjects without clinically overt CVD has been somewhat improved by integrating multiple traditional risk factors via appropriate risk score programs. Nevertheless, novel measures of CVD risk are being proposed and debated to further improve high-risk detection by their addition to, or their use in place of, traditional risk factors. Among such measures, non-invasive detection of subclinical arterial disease is a subject of growing interest. It may improve CVD risk evaluation and enable more intensive risk-reduction therapy in subjects judged to be at intermediate risk after preliminary risk factor assessment. However, the clinical utility and cost-effectiveness of high-risk diagnostic and therapeutic strategy guided by subclinical arterial disease remain untested. This uncertainty precludes systematic detection of subclinical arterial disease in routine clinical management for primary prevention, but such detection may be used at the discretion of the physician as a part of CVD risk assessment.

Relation between coronary artery calcium and incident chest pain in a community-dwelling screening population

Incident chest pain occurred in 30.3% of 1,743 asymptomatic healthy men and women who were followed for up to 4 years. Proportions of patients who had coronary artery calcium were similar among those who had no chest pain, noncardiac pain, atypical pain, or cardiac chest pain. Incident chest pain is common and should be examined according to a patient's pretest probability of developing coronary artery disease, without excessive influence of the presence of coronary artery calcium.

Mineral volume and morphology in carotid plaque specimens using high-resolution MRI and CT

OBJECTIVE

High-resolution MRI methods have been used to evaluate carotid artery atherosclerotic plaque content. The purpose of this study was to assess the performance of high-resolution MRI in evaluation of the quantity and pattern of mineral deposition in carotid endarterectomy (CEA) specimens, with quantitative micro-CT as the gold standard.

METHODS AND RESULTS

High-resolution MRI and CT were compared in 20 CEA specimens. Linear regression comparing mineral volumes generated from CT (VCT) and MRI (VMRI) data demonstrated good correlation using simple thresholding (VMRI=-0.01+0.98VCT; R2=0.90; threshold=4xnoise) and k-means clustering methods (VMRI=-0.005+1.38VCT; R2=0.93). Bone mineral density (BMD) and bone mineral content (BMC [mineral mass]) were calculated for CT data and BMC verified with ash weight. Patterns of mineralization like particles, granules, and sheets were more clearly depicted on CT.

CONCLUSIONS

Mineral volumes generated from MRI or CT data were highly correlated. CT provided a more detailed depiction of mineralization patterns and provided BMD and BMC in addition to mineral volume. The extent of mineralization as well as the morphology may ultimately be useful in assessing plaque stability.

Differences between markers of atherogenic lipoproteins in predicting high cardiovascular risk and subclinical atherosclerosis in asymptomatic men

OBJECTIVE

As main markers of atherogenic lipoproteins, apolipoprotein B (apoB), non-HDL cholesterol (non-HDLC), and LDL cholesterol (LDLC) do not seem equipotent to predict cardiovascular complications, we have compared simultaneously their capacity to predict high cardiovascular risk and subclinical atherosclerosis in a primary prevention population.

METHODS

In 723 asymptomatic men, we measured apoB, non-HDLC, and LDLC, and we determined concomitantly coronary heart disease (CHD) risk equivalent defined by National Cholesterol Education Program guidelines, ultrasound-assessed extra-coronary plaques at multiple sites, and electron beam computed tomography-assessed high coronary calcium.

RESULTS

Odds ratios (95% confidence interval) per standard deviation of apoB, non-HDLC, and LDLC of having: (i) CHD risk equivalent were 1.90 (1.53-2.37), 1.78 (1.43-2.21), 1.47 (1.19-1.81); (ii) extra-coronary plaques were 1.37 (1.16-1.61), 1.31 (1.11-1.56), 1.19 (1.01-1.39); (iii) high coronary calcium were 1.35 (1.09-1.68), 1.33 (1.07-1.64), 1.26 (1.01-1.39), respectively. Risk factors and treatment did not confound the above associations, except triglycerides for which adjustment weakened the risk predictions of lipids and annihilated lipids differences in predicting CHD risk equivalent and atherosclerosis markers.

CONCLUSIONS

ApoB was the best predictor, non-HDLC the second best predictor, and LDLC the poorest predictor of high cardiovascular risk and subclinical extra-coronary and coronary atherosclerosis, and triglycerides participated to these differences.

Coronary Artery Calcium: Associations with Brain Magnetic Resonance Imaging Abnormalities and Cognitive Status

OBJECTIVES

To evaluate the association between coronary atherosclerosis and subclinical brain magnetic resonance imaging (MRI) abnormalities and between coronary atherosclerosis and abnormal cognitive function (dementia/mild cognitive impairment).

DESIGN

Cross-sectional.

SETTING

The Cardiovascular Health Study (CHS), an epidemiological study of risk factors for cardiovascular disease in older adults.

PARTICIPANTS

Four hundred nine men and women, mean age 79, recruited from the Pittsburgh center of the CHS.

MEASUREMENTS

Coronary atherosclerosis was defined according to the level of coronary artery calcification (CAC), as measured using electronic beam tomography. Subclinical brain MRI abnormalities included ventricular enlargement, white matter hyperintensities, and number of subcortical brain infarcts. Brain MRI and CAC measurements were performed between 1998 and 2000 at the Pittsburgh center of the CHS. Prevalence of brain MRI abnormalities and abnormal cognitive status were examined across quartiles of the CAC score, before and after controlling for age. Multivariate logistic regression models were used to assess whether CAC level was associated with abnormalities of brain MRI or abnormal cognitive status.

RESULTS

Older adults with high CAC scores were more likely to have more-severe brain MRI abnormalities, including subcortical infarction and high white matter hyperintensities. The associations between CAC and ventricular enlargement showed a similar but not significant trend. The presence of any of the MRI abnormalities attenuated the association between CAC and abnormal cognitive status.

CONCLUSION

Older adults with higher levels of CAC were more likely to have more-severe brain MRI abnormalities and abnormal cognitive status.

Coronary artery and abdominal aortic calcification are associated with cardiovascular disease in type 2 diabetes

AIMS/HYPOTHESIS

The goals of this study were to determine whether coronary calcium is associated with the presence of clinical cardiovascular disease in individuals with type 2 diabetes and if the measurement of abdominal aortic calcium may have an independent or added benefit as a surrogate marker for clinical vascular disease.

METHODS

A cross-sectional study of subjects with type 2 diabetes enrolled in seven medical centres in the USA participating in a Veterans Affairs Cooperative Study of glycaemic control. Enrolled subjects included 309 veterans over 40 years of age with type 2 diabetes, with or without stable cardiovascular disease, who had inadequate glycaemic control (HbA(1)c>7.5%) on oral agents and/or insulin. The study assessed lifestyle behaviours, standard cardiovascular risk factors and coronary artery and abdominal aorta calcification by electron beam computed tomography.

RESULTS

Subjects with coronary artery or abdominal aorta calcification present had a strikingly higher prevalence of peripheral artery disease, coronary artery disease and all combined cardiovascular disease. Prevalence of each condition increased from 5- to 13-fold with increasing quintiles of coronary artery calcification and from 2- to 3-fold with increasing abdominal aorta calcification. These associations persisted after adjustment for lifestyle behaviours and standard cardiovascular risk factors.

CONCLUSIONS/INTERPRETATION

These results support the notion that vascular calcium in type 2 diabetes provides additional information beyond that of standard risk factors in identifying the presence of cardiovascular disease. Subclinical measures of atherosclerosis such as arterial calcification may help more precisely stratify these individuals and alert healthcare providers to those individuals who have particularly accelerated atherosclerosis.

Carotid bifurcation calcium and correlation with percent stenosis of the internal carotid artery on CT angiography

The aim of this paper was to determine the correlation between calcium burden (expressed as a volume) and extent of stenosis of the origin of the internal carotid artery (ICA) by CT angiography (CTA). Previous studies have shown that calcification in the coronary arteries correlates with significant vessel stenosis, and severe calcification (measured by CT) in the carotid siphon correlates with significant (greater than 50% stenosis) as determined angiographically. Sixty-one patients (age range 50-85 years) underwent CT of the neck with intravenous administration of iodinated contrast for a variety of conditions. Images were obtained with a helical multidetector array CT scanner and reviewed on a three-dimensional workstation. A single observer manipulated window and level to segment calcified plaque from vascular enhancement in order to quantify vascular calcium volume (cc) in the region of the bifurcation of the common carotid artery/ICA origin, and to measure the extent of ICA stenosis near the origin. A total of 117 common carotid artery bifurcations were reviewed. A "significant" stenosis was defined arbitrarily as >40% (to detect lesions before they become hemodynamically significant) of luminal diameter on CTA using NASCET-like criteria. All "significant" stenoses (21 out of 117 carotid bifurcations) had measurable calcium. We found a relatively strong correlation between percent stenosis and the calcium volume (Pearson's r = 0.65, P<0.0001). We also found that there was an even stronger correlation between the square root of the calcium volume and the percent stenosis as measured by CTA (r= 0.77, P<0.0001). Calcium volumes of 0.01, 0.03, 0.06, 0.09 and 0.12 cc were used as thresholds to evaluate for a "significant" stenosis. A receiver operating characteristic (ROC) curve demonstrated that thresholds of 0.06 cc (sensitivity 88%, specificity 87%) and 0.03 cc (sensitivity 94%, specificity 76%) generated the best combinations of sensitivity and specificity. Hence, this preliminary study demonstrates a relatively strong relationship between volume of calcium at the carotid bifurcation in the neck (measured by CT) and percent stenosis of the ICA below the skull base (as measured by CTA). Use of calcium volume measurements as a threshold may be both sensitive and specific for the detection of significant ICA stenosis. The significance of the correlation between calcium volume and ICA stenosis is that potentially a "score" can be obtained that will identify those at risk for high grade carotid stenosis.

Alcohol intake is not associated with subclinical coronary atherosclerosis

BACKGROUND

The inverse relation between alcohol intake and clinical coronary artery disease (CAD) is well established, although the mechanisms remain speculative. We studied the relation between alcohol intake and subclinical CAD to assess the possible role of alcohol in atherogenesis.

METHODS

We conducted a prospective study of 731 consecutive, consenting, active-duty US Army personnel (39 to 45 years of age) without known CAD who were undergoing a routine physical examination. Each participant was surveyed with the validated Block dietary questionnaire, which included detailed information on alcohol intake as wine, beer, or liquor. Subclinical CAD was determined by means of electron beam computed tomography to quantify coronary artery calcification (CAC).

RESULTS

The mean age was 42 (+/-2); 83% were male, 71% were white, and 82% were college graduates. The prevalence of CAC was 18.6% (mean CAC score = 12 +/- 69). Twenty-two percent drank alcohol daily, with an average of 2.4 drinks per day. Systolic blood pressure was correlated with number of drinks per day (r = 0.10, P = .025). Among drinkers, HDL was weakly correlated with daily alcohol consumption (r = 0.10, P = .025). There was no relation between the CAC score and the alcohol intake as measured by drinks per day (OR, 1.02; 95% CI, 0.64 to 1.63; 1.13, 0.59 to 2.15; 1.26, 0.69 to 2.59, for less than 1, 1 to 2, and more than 2 drinks per day, respectively). Stratified analyses based on type of alcohol and multivariate analyses indicated no independent relation between any type or quantity of alcohol intake and the presence or extent of coronary calcification.

CONCLUSIONS

Alcohol intake does not appear to be inversely related to subclinical CAC, implying that previous observations of a protective effect of alcohol on clinical CAD may involve factors related to plaque stability rather than atherogenesis.

Coronary calcium by spiral computed tomography predicts cardiovascular events in high-risk hypertensive patients

OBJECTIVE

The ability of coronary artery calcium (CAC) to predict coronary events has been shown in several studies. We aimed to investigate the hypothesis that CAC as assessed by dual slice spiral computed tomography (DSCT), is an independent risk factor for cardiovascular events in hypertensive patients.

METHODS

We followed 446 participants of INSIGHT (International Nifedipine Study Intervention as Goal for Hypertension Therapy) calcification study, for the incidence of cardiovascular events as a function of CAC and other factors. All were hypertensive, without coronary artery disease (CAD), ages > 55 years and with at least one more major cardiovascular risk factor. All underwent a baseline DSCT and were followed for a mean period of 3.8 +/- 0.4 years. All events were documented while the scheduled visits and confirmed by the INSIGHT critical event committee.

RESULTS

Follow-up was conducted on all participants. 294 patients (66%) had CAC at baseline. Forty-seven patients experienced a first cardiovascular event: acute myocardial infarction (MI), 16; sudden cardiac death, two; unstable angina resulting in revascularization, 14; stroke, 15. The incidence of first cardiovascular events was 3.7 times higher among those who had CAC at baseline than among those who had no CAC (14.5% (41 of 294) versus 3.9% (6 of 152)). Patients who experienced an event were more likely to be males, had had higher prevalence of peripheral vascular disease, longer duration of hypertension, and had higher levels of systolic blood pressure (SBP), glucose, creatinine and uric acid. Adjusting for these covariates, CAC (total coronary calcium score (TCS) > 0) independently predicted cardiovascular events with an odds ratio (OR) of 2.76 [95% confidence interval (CI) 1.09-6.99, P = 0.032].

CONCLUSION

The presence of CAC predicts cardiovascular events in high-risk asymptomatic hypertensive patients.

Blood pressure and atherosclerotic plaques in carotid, aortic and femoral arteries in elderly Finns with diabetes mellitus or impaired glucose tolerance

The aim of the study was to evaluate the occurrence of atheromatous plaques in carotid, aortic and femoral arteries, focusing on blood pressure (BP). The study subjects consisted of 65-year-old Finns drawn from a population-based cohort. Ultrasonographic measurements were performed on 54 diabetic subjects, 97 subjects with impaired glucose tolerance (IGT) and 57 normoglycaemic subjects (NGT). High systolic BP (SBP) was defined as >or=160 mmHg and high diastolic BP as >or=95 mmHg. High pulse pressure (PP) was defined as the highest tertile (>or=75 mmHg) of PP and high mean BP (MBP) as the highest tertile (>or=111 mmHg) of MBP. The prevalence of atheromatous plaques was 77% (160/208) in carotid arteries, 94% (195/208) in aorta and 77% (161/208) in femoral arteries. A total of 64% (134/208) of the subjects had plaques in both carotid and femoral arteries, and they were compared with those who had plaques in 0-1 of these arteries. In addition to male gender and long-lasting smoking, the occurrence of plaques in both carotid and femoral arteries were associated with high SBP and high MBP. According to the results of multiple regression analyses, the adjusted odds ratio for plaques in both carotid and femoral arteries was 3.1 (95% CI 1.5-6.5) in subjects with high SBP compared to those with lower SBP. When SBP was replaced by high MBP, the adjusted odds ratio for it was 2.3 (95% CI 1.1-4.8).

Effective doses of ibandronate do not influence the 3-year progression of aortic calcification in elderly osteoporotic women

Animal experiments revealed conflicting results as to the impact of bisphosphonate treatment on atherosclerosis and related vascular calcification. The effect of long-term treatment with clinical doses of bisphosphonates on aortic calcification (AC) in an "at-risk" population of osteoporotic elderly women has not been assessed systematically. In the present analysis including 474 women (55-80 years) participating in two 3-year randomized, placebo-controlled clinical trials, we assessed the simultaneous impact of ibandronate given either orally (2.5 mg daily or 20 mg intermittently) or intravenously (0.5 mg or 1.0 mg IV every 3 months) on bone mass and AC. All women received calcium and vitamin D supplements. Bone mineral density (BMD) was measured at the lumbar spine and the total hip using dual-energy X-ray absorptiometry (DXA). Calcified deposits of the lumbar aorta (L1-L4) were visualized on lateral radiographs and severity was graded by a validated scoring system. Measurements were performed at baseline and at years 1, 2, and 3. At baseline, there was a significant inverse correlation between the severity of AC and BMD at the hip (r=-0.151, P=0.003), but not at the lumbar spine. The two oral doses and the 1.0 mg IV dose evoked statistically significant increases in both hip and spine BMD compared with placebo, whereas the effect of 0.5 mg was significant only at the hip (P<0.05). No differences in the yearly rate of progression or the 3-year change in AC was observed between the different intervention groups. Furthermore, there were no statistically significant correlations between the 3-year change in BMD and the simultaneous change in AC. These findings thus suggest that 3-year treatment with effective doses of ibandronate does not pose any cardiovascular risk in terms of altering vascular calcification.