Components of the metabolic syndrome and carotid atherosclerosis: role of elevated blood pressure

Modulation of arterial intima stiffness by disturbed blood flow

The intima, comprising the endothelium and the subendothelial matrix, plays a crucial role in atherosclerosis pathogenesis. The mechanical stress arising from disturbed blood flow (d-flow) and the stiffening of the arterial wall contributes to endothelial dysfunction. However, the specific impacts of these physical forces on the mechanical environment of the intima remain undetermined. Here, we investigated whether inhibiting collagen crosslinking could ameliorate the detrimental effects of persistent d-flow on the mechanical properties of the intima. Partial ligation of the left carotid artery (LCA) was performed in C57BL/6J mice, inducing d-flow. The right carotid artery (RCA) served as an internal control. Carotids were collected 2 days and 2 weeks after surgery to study acute and chronic effects of d-flow on the mechanical phenotype of the intima. The chronic effects of d-flow were decoupled from the ensuing arterial wall stiffening by administration of β-aminopropionitrile (BAPN), an inhibitor of collagen crosslinking by lysyl oxidase (LOX) enzymes. Atomic force microscopy (AFM) was used to determine stiffness of the endothelium and the denuded subendothelial matrix in en face carotid preparations. The stiffness of human aortic endothelial cells (HAEC) cultured on soft and stiff hydrogels was also determined. Acute exposure to d-flow caused a slight decrease in endothelial stiffness in male mice but had no effect on the stiffness of the subendothelial matrix in either sex. Regardless of sex, the intact endothelium was softer than the subendothelial matrix. In contrast, exposure to chronic d-flow led to a substantial increase in the endothelial and subendothelial stiffness in both sexes. The effects of chronic d-flow were largely prevented by concurrent BAPN administration. In addition, HAEC displayed reduced stiffness when cultured on soft vs. stiff hydrogels. We conclude that chronic d-flow results in marked stiffening of the arterial intima, which can be effectively prevented by inhibition of collagen crosslinking.

Predictors of Carotid Atherosclerosis Progression: Evidence from an Ultrasonography Laboratory

BACKGROUND AND PURPOSE

The purpose of this study was to investigate the role of risk factors in predicting the variation in carotid atherosclerosis at ultrasonographic follow-up and, therefore, its role in the progression of large-vessel disease.

METHODS

This retrospective population study included all the outpatients that underwent at least two carotid ultrasonographies at our laboratory from 2001 to 2017. Demographic data, vascular risk factors, and the results at follow-up were analysed to determine if correlations exist between these risk factors and variation in carotid atherosclerosis.

RESULTS

Data from 600 patients (327 males and 273 females with a mean age of 67 years) were collected. The mean follow-up period was 49 months (range: 1-195). We analysed each demographic variable and risk factor to assess its correlation with a worsening of carotid atherosclerosis; previous myocardial infarction (2.594), previous carotid surgical treatment (2.368), and hypertension (1.85) were found to have the highest odds ratios, respectively. Furthermore, the sample was divided into specific subpopulations (diabetes, hypertension, and smoking), and an association was found between age and worsening stenosis.

DISCUSSION AND CONCLUSIONS

Our results confirm the importance of carotid ultrasonographic follow-up in the monitoring and managing of large-vessel disease. Myocardial infarction, previous stroke, and previous surgical treatment were the strongest predictors of a worsening of carotid atherosclerosis. These findings suggest a strict follow-up is needed, even in the absence of significant carotid atherosclerosis at baseline.

METABOLIC AND HORMONAL FEATURES OF CHRONIC HEART FAILURE IN PERSONS WITH POST-INFARCTION CARDIOSCLEROSIS WITH TYPE 2 DIABETES MELLITUS AND OBESITY

OBJECTIVE

The aim: To determine the role of lipid metabolism and fractalkin and clusterin in the progression of chronic heart failure in patients with postinfarction cardiosclerosis with concomitant type 2 diabetes and obesity.

PATIENTS AND METHODS

Materials and methods: A retrospective analysis of a comprehensive examination of 67 patients with postinfarction cardiosclerosis with concomitant type 2 diabetes and obesity. All patients were divided into 3 groups depending on the functional class (FC) of CHF: 1 group (n = 22) - patients with CHF II FC; Group 2 (n = 23) - patients with CHF III FC; Group 3 (n = 22) - patients with CHF IV FC. All patients were examined clinically, they were instrumental, biochemical and hormonal examination.

RESULTS

Results: With the progression of CHF from FC II to FC III there is a deterioration of lipid metabolism: a significant increase in cholesterol levels by 5.5%, TG - by 15.7%, LDL cholesterol - by 74.4%, VLDL cholesterol - by 15 , 9%, reduction of HDL cholesterol - by 27.6% (p <0,05). An analysis of the fractal equation showing that ailing on CHF is advised by FC; rіven clusterin -decrease.

CONCLUSION

Conclusions: Classical changes in patients with postinfarction cardiosclerosis with CHF and concomitant type 2 diabetes mellitus and obesity , which are the formation of atherogenic lipid metabolism disorders associated with body weight, as well as changes in the latest indicators such as fractalkin and clusterin , indicating the role of these molecules in the progression of CHF.

Metabolic Syndrome and Coronary Artery Disease Risk: A Meta-Analysis of Observational Studies

Although numerous studies have described the link between metabolic syndrome (MetS) and Coronary Artery Disease (CAD), no meta-analysis has been carried out on this relationship. Thus, the present study intended to address this limitation. A systematic search was carried out using electronic databases, such as PubMed, CINAHL Plus, Medline, and Web of Science. A sum of 10 studies (n = 9327) was incorporated in the meta-analysis. Compared with non-MetS, MetS was significantly associated with high CAD risk (OR = 4.03, 95% CI = 3.56–4.56). The MetS components were also significantly correlated with high CAD risk (OR = 3.72, 95% CI = 3.22–4.40). The presence of two (OR = 3.93, 95% CI = 2.81–5.49), three (OR = 4.09, 95% CI = 2.85–5.86), four (OR = 4.04, 95% CI = 2.83–5.78), or all five MetS components (OR = 3.92, 95% CI = 3.11–4.93), were significantly associated with a high risk of CAD. MetS and its individual or combined elements were linked with high CAD risk based on contemporary evidence. Thus, the assessment of MetS and its components might help identify people at a higher risk of advancing CAD in the future.

Long-term clinical outcomes according to the mean observed blood pressure in patients with coronary artery disease after drug-eluting stent implantation

BACKGROUND

A recent guideline emphasized strict blood pressure (BP) control for the patients at high risk for cardiovascular events. However, there are little data about the relationship between BP control and clinical outcome in Korea. We sought to evaluate the clinical outcomes according to the mean observed BP in patients with coronary artery disease (CAD) who had undergone drug-eluting stent (DES) implantation.

METHODS

We reviewed records of 1010 CAD patients with DES from 2010 through 2011. After excluding in-hospital mortality cases (n = 79), we categorized patients into two groups based on the average SBP (SBP) at the outpatient clinic: mean SBP 120 mmHg or less (n = 290) and mean SBP greater than 120 mmHg (n = 641). Primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCEs), defined as cardiac death, myocardial infarction, repeat target vessel revascularization, or stroke. Propensity score matching was performed to adjust for differences in baseline clinical variables. Median follow-up duration was 77.7 (36.6-87.3) months.

RESULTS

The mean SBP greater than 120 mmHg had higher prevalence of cardiovascular risk factors, such as diabetes (38.4 vs. 27.2%, P = 0.001), hypertension (58.8 vs. 32.4%, P < 0.001), and chronic kidney disease (3.3 vs. 1.0%, P = 0.043) than mean SBP 120 mmHg or less. MACCE incidence was significantly lower in the mean SBP 120 mmHg or less than in the mean SBP greater than 120 mmHg (14.3 vs. 22.0%, P = 0.007) at 77.7 months. Even after propensity score matching, the mean SBP 120 mmHg or less showed significantly reduced MACCE rate (14.3 vs. 22.8%, P = 0.007).

CONCLUSION

Mean observed SBP 120 mmHg or less was associated with a lower incidence of future adverse outcomes in CAD patients with DES.

Hypertension and decreased aortic compliance due to reduced elastin amounts do not increase atherosclerotic plaque accumulation in Ldlr-/- mice

BACKGROUND AND AIMS

High blood pressure and reduced aortic compliance are associated with increased atherosclerotic plaque accumulation in humans. Animal studies support these associations, but additional factors, such as fragmented elastic fibers, are present in most previous animal studies. Elastin heterozygous (Eln+/-) mice have high blood pressure and reduced aortic compliance, with no evidence of elastic fiber fragmentation and represent an appropriate model to directly investigate the effects of these factors on atherosclerosis.

METHODS AND RESULTS

Eln+/- and Eln+/+ mice were crossed with low density lipoprotein receptor knockout (Ldlr-/-) and wild-type (Ldlr+/+) mice and fed normal or Western diet (WD) for 16 weeks. We hypothesized that on WD, Eln+/-Ldlr-/- mice with high blood pressure and reduced aortic compliance would have increased atherosclerotic plaque accumulation compared to Eln+/+Ldlr-/- mice. We measured serum cholesterol and cytokine levels, blood pressure, aortic compliance, and plaque accumulation. Contrary to our hypothesis, we found that on WD, Eln+/-Ldlr-/- mice do not have increased plaque accumulation compared to Eln+/+Ldlr-/- mice. At the aortic root, there are no significant differences in plaque area between Eln+/-Ldlr-/- and Eln+/+Ldlr-/- mice on WD (p = 0.89), while in the ascending aorta, Eln+/-Ldlr-/- mice on WD have 29% less normalized plaque area than Eln+/+Ldlr-/- mice on WD (p = 0.009).

CONCLUSION

Using an atherogenic mouse model, we conclude that increased blood pressure and reduced aortic compliance are not direct causes of increased aortic plaque accumulation. We propose that additional insults, such as fragmentation of elastic fibers, are necessary to alter plaque accumulation.

Spirometric prediction equations and the relationship between metabolic syndrome and spirometric parameters from an island in Fujian, China

BACKGROUND

We investigated risk factors for decreased lung function among Chinese island residents (≥30 years) to determine the relationship between metabolic syndrome (MS) and decreased lung function.

METHODS

From October 17, 2011 to November 1, 2011, 2607 residents aged ≥30 years who lived on the Huangqi Peninsula of Fujian were enlisted by random cluster sampling. They completed a questionnaire designed according to the Burden of Obstructive Lung Disease (BOLD) questionnaire, and underwent physical examination, blood test, and lung function evaluation. We constructed spirometric prediction equations for forced vital capacity (FVC) and forced expiratory volume in one second (FEV1), determined the lower limits of normal for FVC, FEV1 and FEV1/FVC, and examined the relationship between lung function and MS.

RESULTS

Prediction equations for normal island residents were as follows: FVC (L) = -0.023 × age (years) + 0.042 × height (cm) + 0.641 × weight (kg) - 3.607 (males); FVC (L) = -0.017 × age (years) + 0.030 × height (cm) + 0.009 × weight (kg) - 1.741 (females); FEV1 (L) = -0.023 × age (years) + 0.040 × height (cm) + 0.010 × weight (kg) - 2.999 (males); FEV1 (L) = -0.017 × age (years) + 0.026 × height (cm) + 0.007 × weight (kg) -1.135 (females). The odds ratio for MS for increased risk of decreased FVC was 4.623 (95%CI =3.626-5.894, P<0.001), and for increased risk of decreased FEV1 was 3.043 (95%CI =2.447-3.785, P<0.001).

CONCLUSIONS

MS is a risk factor for decreased lung function in island residents ≥30 years old.

Metabolic syndrome in hypertensive patients: An unholy alliance

For many years, it has been recognized that hypertension tends to cluster with various anthropometric and metabolic abnormalities including abdominal obesity, elevated triglycerides, reduced high-density lipoprotein cholesterol, glucose intolerance, insulin resistance and hyperuricemia. This constellation of various conditions has been transformed from a pathophysiological concept to a clinical entity, which has been defined metabolic syndrome (MetS). The consequences of the MetS have been difficult to assess without commonly accepted criteria to diagnose it. For this reason, on 2009 the International Diabetes Federation, the American Heart Association and other scientific organizations proposed a unified MetS definition. The incidence of the MetS has been increasing worldwide in parallel with an increase in overweight and obesity. The epidemic proportion reached by the MetS represents a major public health challenge, because several lines of evidence showed that the MetS, even without type 2 diabetes, confers an increased risk of cardiovascular morbidity and mortality in different populations including also hypertensive patients. It is likely that the enhanced cardiovascular risk associated with MetS in patients with high blood pressure may be largely mediated through an increased prevalence of preclinical cardiovascular and renal changes, such as left ventricular hypertrophy, early carotid atherosclerosis, impaired aortic elasticity, hypertensive retinopathy and microalbuminuria. Indeed, many reports support this notion, showing that hypertensive patients with MetS exhibit, more often than those without it, these early signs of end organ damage, most of which are recognized as significant independent predictors of adverse cardiovascular outcomes.

Blood viscosity in subjects with normoglycemia and prediabetes

OBJECTIVE

Blood viscosity (BV) is higher in diabetic patients and might represent a risk factor for the development of insulin resistance and type 2 diabetes. However, data in subjects with normal glucose or prediabetes are missing. In the current study, we evaluated the relationship between BV and blood glucose in subjects with normal glucose or prediabetes.

RESEARCH DESIGN AND METHODS

Enrolled subjects were divided into three groups according to blood glucose: group A (n = 74), blood glucose <90 mg/dL; group B (n = 96), blood glucose ranging from 90 to 99 mg/dL; and group C (n = 94), blood glucose ranging from 100 to 125 mg/dL. BV was measured at 37°C with a cone-plate viscometer at shear rates ranging from 225 to 22.5 s(-1).

RESULTS

Blood pressure, blood lipids, fibrinogen, and plasma viscosity were similar in the three groups. BMI and waist circumference were significantly increased in group C. Hematocrit (P < 0.05) and BV (P between 0.01 and 0.001) were significantly higher in groups B and C compared with group A. Blood glucose was significantly and inversely correlated with HDL cholesterol and directly with BMI, waist, hematocrit (r = 0.134), and BV (from 225 s(-1) to 22.5 s(-1); r ranging from 0.162 to 0.131). BV at shear rate 225 s(-1) was independently associated with blood glucose.

CONCLUSIONS

The current study shows a direct relationship between BV and blood glucose in nondiabetic subjects. It also suggests that, even within glucose values considered completely normal, individuals with higher blood glucose levels have increased BV comparable with that observed in subjects with prediabetes.

The relationship of flow velocities to vessel diameters differs between extracranial carotid and vertebral arteries of stroke patients

BACKGROUND

Chronic changes in flow rate through arteries produce adjustment of arterial diameters. We compared the relationship between flow velocity and diameter in the carotid and in the vertebral arteries of stroke patients.

METHODS

Using triplex ultrasonography, the internal diameter and flow velocities of the common carotid, internal carotid, and vertebral arteries of 176 consecutive stroke patients were measured. Correlations were examined with Pearson's statistics at an alpha level of 0.05.

RESULTS

Mean age of the patients was 59.3 ± 12 years, and 66% had cerebral infarcts. Diameter and blood flow velocities showed significant negative correlations (-0.115 ≥ r ≥ -0.382) in the carotid arteries on both sides, but positive correlations (0.211 ≤ r ≤ 0.320) in the vertebral arteries, even after controlling for age, gender, and blood pressure.

CONCLUSIONS

Our study demonstrated different diameter/flow relationships in the carotid and the vertebral arteries of stroke patients, which may suggest pathologic changes in the adaptive processes governing vessel diameter and growth, especially in the carotid arteries.

Systemic inflammation and lung function impairment in morbidly obese subjects with the metabolic syndrome

BACKGROUND

Obesity and asthma are associated. There is a relationship between lung function impairment and the metabolic syndrome. Whether this relationship also exists in the morbidly obese patients is still unknown. Hypothesis. Low-grade systemic inflammation associated with the metabolic syndrome causes inflammation in the lungs and, hence, lung function impairment.

METHODS

This is cross-sectional study of morbidly obese patients undergoing preoperative screening for bariatric surgery. Metabolic syndrome was assessed according to the revised NCEP-ATP III criteria.

RESULTS

A total of 452 patients were included. Patients with the metabolic syndrome (n = 293) had significantly higher blood monocyte (mean 5.3 versus 4.9, P = 0.044) and eosinophil percentages (median 1.0 versus 0.8, P = 0.002), while the total leukocyte count did not differ between the groups. The FEV1/FVC ratio was significantly lower in patients with the metabolic syndrome (76.7% versus 78.2%, P = 0.032). Blood eosinophils were associated with FEV1/FVC ratio (adj. B -0.113, P = 0.018).

CONCLUSION

Although the difference in FEV1/FVC ratio between the groups is relatively small, in this cross-sectional study, and its clinical relevance may be limited, these data indicate that the presence of the metabolic syndrome may influence lung function impairment, through the induction of relative eosinophilia.

Generation and characterization of a mouse model of the metabolic syndrome: apolipoprotein E and aromatase double knockout mice

The aim of this study was to create a comprehensive mouse model of the metabolic syndrome by crossing aromatase-deficient (ArKO) mice with apolipoprotein E-deficient (ApoE(-/-)) mice. Successive crossbreeding of ArKO with ApoE(-/-)-deficient mice generated double knockout, MetS-Tg mice. The phenotypic characteristics of the MetS-Tg mice were assessed at 3, 6, and 12 mo of age and compared with age- and sex-matched wild-type (WT) controls. Blood pressure and heart rate were recorded by a noninvasive, computerized tail-cuff system. Oral glucose and intraperitoneal insulin tolerance tests were performed. Serum cholesterol levels were measured by a combined quantitative colorimetric assay. Plasma adiponectin, C-reactive protein (CRP), insulin, interleukin-6 (IL-6), leptin, resistin, and tumor necrosis factor-α (TNF-α) were measured by multiplexed ELISA. MetS-Tg mice displayed significantly increased body weight, central obesity, and elevated blood pressure at all three ages compared with WT mice. Elevated serum cholesterol was associated with higher triglycerides and LDL/VLDL cholesterol particles and was accompanied by a decrease in HDL and histological evidence of fatty liver. MetS-Tg mice of all ages showed impaired glucose tolerance. At 12 mo, MetS-Tg mice had elevated plasma levels of CRP, IL-6, leptin, and TNF-α, but resistin levels were largely unchanged. We now report that this combination of gene knockouts produces a novel strain of mice that display the diverse clinical features of the metabolic syndrome, including central obesity, progressive hypertension, an adverse serum lipid profile, fatty liver, glucose intolerance, insulin resistance, and evidence of an inflammatory state.

Sex differences in obesity-related changes in left ventricular morphology: the Strong Heart Study

OBJECTIVES

It is unclear whether there are sex differences in the relations of left ventricular mass to body composition and fat distribution in nonobese or obese hypertensive and nonhypertensive individuals and whether the obesity-related increase in left ventricular mass is similar in men and women.

METHODS

We examined sex differences in the relations between left ventricular mass and both body composition and fat distribution, in the presence or absence of obesity in 1068 men and 1851 women (65%) of the Strong Heart Study cohort, without prevalent cardiovascular disease or severe chronic kidney disease. Fat-free mass (FFM) and adipose mass were estimated by bioelectric impedance analysis and fat distribution by waist-to-hip ratio (WHR).

RESULTS

Adipose mass was significantly higher in women than in men for any weight category (P < 0.0001). After adjusting for age, hypertension, systolic blood pressure (BP) and diabetes, both left ventricular mass/height (LVMi) and left ventricular mass (LVM)/FFM were greater in obese women than obese men (P < 0.0001). Relative wall thickness was also greater in women than in men (P < 0.0001). LVM was independently related to Doppler-stroke volume, FFM and systolic BP in both sexes, with WHR and adipose mass contributing to variance of LVM in women but not in men (both P < 0.03).

CONCLUSION

Obesity influences left ventricular geometry substantially more in women than in men, possibly due to biological factors specifically associated with female adiposity.

Metabolic syndrome and carotid intima media thickness in urban police officers

OBJECTIVE

To examine the association between metabolic syndrome (MetSyn) and carotid intima media thickness (IMT) separately in male and female police officers.

METHODS

MetSyn was defined using 2005 guidelines. B-mode ultrasound was used to measure mean and maximum (12 and 36 segments) carotid artery thickness. Analysis of covariance was used to compare mean IMT values across individuals categorized by number of MetSyn components. Adjustments were made for age, smoking status, and low-density lipoprotein cholesterol.

RESULTS

Among 106 women, the adjusted mean common and maximum36 carotid IMT were significantly and positively associated with number of MetSyn components. No associations were found in men (n = 304). Adjusted carotid IMT values were inversely associated with low high-density lipoprotein cholesterol and directly with hypertension in women.

CONCLUSIONS

Number of MetSyn components was significantly associated with carotid IMT in female but not in male officers.

Worksite health screening programs for predicting the development of Metabolic Syndrome in middle-aged employees: a five-year follow-up study

BACKGROUND

Metabolic syndrome (MetS) management programs conventionally focus on the adults having MetS. However, risk assessment for MetS development is also important for many adults potentially at risk but do not yet fulfill MetS criteria at screening. Therefore, we conducted this follow-up study to explore whether initial screening records can be efficiently applied on the prediction of the MetS occurrence in healthy middle-aged employees.

METHODS

Utilizing health examination data, a five-year follow-up observational study was conducted for 1384 middle-aged Taiwanese employees not fulfilling MetS criteria. Data analyzed included: gender, age, MetS components, uric acid, insulin, liver enzymes, sonographic fatty liver, hepatovirus infections and lifestyle factors. Multivariate logistic regression was used to estimate the adjusted odds ratios (OR) and 95% confidence interval (CI) of risk for MetS development. The synergistic index (SI) values and their confidence intervals of risk factor combinations were calculated; and were used to estimate the interacting effects of coupling MetS components on MetS development.

RESULTS

Within five years, 13% (175 out of 1384) participants fulfilled MetS criteria. The ORs for MetS development among adults initially having one or two MetS components were 2.8 and 7.3, respectively (both p < 0.01), versus the adults having zero MetS component count at screening. Central obesity carried an OR of 7.5 (p < 0.01), which far exceeded other risk factors (all ORs < 2.7). Synergistic effects on MetS development existed between coupling MetS components: 1. High blood pressure plus low-HDL demonstrated an OR of 11.7 (p < 0.01) for MetS development and an SI of 4.7 (95% CI, 2.1-10.9). 2. High blood pressure plus hyperglycemia had an OR of 7.9 (p < 0.01), and an SI of 2.7 (95% CI, 1.2-6.4).

CONCLUSION

MetS component count and combination can be used in predicting MetS development for participants potentially at risk. Worksite MetS screening programs simultaneously allow for finding out cases and for assessing risk of MetS development.

Mouse models of the metabolic syndrome

The metabolic syndrome (MetS) is characterized by obesity concomitant with other metabolic abnormalities such as hypertriglyceridemia, reduced high-density lipoprotein levels, elevated blood pressure and raised fasting glucose levels. The precise definition of MetS, the relationships of its metabolic features, and what initiates it, are debated. However, obesity is on the rise worldwide, and its association with these metabolic symptoms increases the risk for diabetes and cardiovascular disease (among many other diseases). Research needs to determine the mechanisms by which obesity and MetS increase the risk of disease. In light of this growing epidemic, it is imperative to develop animal models of MetS. These models will help determine the pathophysiological basis for MetS and how MetS increases the risk for other diseases. Among the various animal models available to study MetS, mice are the most commonly used for several reasons. First, there are several spontaneously occurring obese mouse strains that have been used for decades and that are very well characterized. Second, high-fat feeding studies require only months to induce MetS. Third, it is relatively easy to study the effects of single genes by developing transgenic or gene knockouts to determine the influence of a gene on MetS. For these reasons, this review will focus on the benefits and caveats of the most common mouse models of MetS. It is our hope that the reader will be able to use this review as a guide for the selection of mouse models for their own studies.

[Metabolic Syndrome in professional truck drivers who work on Highway BR-116 within the area of São Paulo City - Régis Bittencourt]

The objective of this study was to determine the Metabolic Syndrome prevalence as well as identify variables related in truck drivers who work on Highway BR-116 (São Paulo, Brazil). A total of 258 truck drivers were assessed and the variables studied were: body mass index, waist circumference, blood pressure, triglycerides, total and fraction cholesterol, glycemia and C reactive protein. Cardiovascular disease risk was evaluated by Framingham's risk score whereas the Metabolic Syndrome based on the First Brazilian Guideline for Diagnosis and Treatment of the Metabolic Syndrome. The significance level adopted was p< 0.05 and univariate and multivariate analysis were applied. The average age was of 37.5+/-10.1. According to the anthropometric data, it was observed body mass index > or =25 kg/m(2) in 82%, waist circumference > or =94 cm in 58%, total cholesterol >240 mg/dL in 9%, LDL-c >160 mg/dL in 10%; HDL-c <40 mg/dL in 20%, triglycerides >200mg/dL in 22%, glycemia >110 mg/dL in 7%, and C reactive protein >0.5 mg/dL in 19%. Hypertension prevalence was 37%, 9% were identified at the highest/medium Framingham's risk score and 24% showed Metabolic Syndrome. The logistical regression analysis indicated independent association of the Metabolic Syndrome for the following variables (OD odds ratio, CI confidence interval at 95%): body mass index (OR = 1.4007 CI 95% 1.192-1.661), use to check cholesterol (OR = 0.1020 CI 0.017-0.589) and Framingham's risk score (OR = 26.389 CI 2.520-276.374). As a conclusion, it was observed a quite expressive prevalence of cardiovascular risk factors as well as Metabolic Syndrome in truck drivers.

Blood pressure has a greater impact on cardiovascular mortality than other components of metabolic syndrome in Koreans

OBJECTIVE

Limited information is currently available on the association of metabolic syndrome or individual components with risk of cardiovascular morbidity and mortality in diverse populations. Here, we investigate the relationship of metabolic syndrome and its individual components with cardiovascular mortality in Korean adults.

METHODS

Data were obtained from 57,237 patients (32,819 men and 24,418 women), aged 40-89 years, subjected to regular health examinations at the Health Promotion Center of Asan Medical Center, Seoul, Korea (1999-2001) and subsequently followed up for a median time of 5.6 years. The risk of cardiovascular mortality was analyzed in relation to metabolic syndrome and its individual components.

RESULTS

The risk of cardiovascular mortality attributable to elevated blood pressure was approximately 52% in men and 72% in women, respectively. Compared to subjects without metabolic syndrome, individuals with metabolic syndrome presented a relative risk (RR) of cardiovascular disease (CVD)-induced death of 1.75 (95% CI, 1.15-2.66). After mutual adjustment for the individual components of metabolic syndrome, elevated blood pressure was significantly associated with CVD death, with RR values of 2.08 (95% CI, 1.27-3.42) in men and 3.56 (95% CI, 1.55-8.19) in women.

CONCLUSION

In Koreans, metabolic syndrome increases the risk of CVD death, with the blood pressure component being the key predictor of mortality.

Associations between cardiovascular risk factors and carotid atherosclerosis in middle-aged Japanese men with multiple risk factors

To examine the relationship between cardiovascular risk factors and prevalence of carotid atherosclerosis in Japanese middle-aged men with multiple risk factors, 110 Japanese men aged 36 to 60 yr were recruited based on the presence of all of the following factors detected during a screening survey: 1) body mass index (BMI) > or = 25 kg/m2; 2) systolic blood pressure (SBP) > or = 140 mmHg and/or diastolic blood pressure > or = 90 mmHg; 3) serum levels of triglycerides (TG) > or = 150 mg/dl and/or total cholesterol (T-ChoL) levels > or = 220 mg/dl and/or high density lipoprotein cholesterol (HDL-C) levels < 40 mg/dl; and 4) fasting serum glucose > or = 110 mg/dl and/or hemoglobin A1C > or = 5.6%. After adjustment for age and cardiovascular risk factors, the odds ratio (95% confidence interval) of carotid atherosclerosis associated with a 1-SD increment in HDL-C was 0.4 (95%CI: 0.2 to 0.9). We also detected a borderline association for anti-hypertension medication use, an indicator for advanced hypertension, with an odds ratio of 2.7 (95%CI: 1.0 to 7.4) after multivariable adjustment. The other risk factors, i.e. BMI, SBP, T-ChoL, TG, diabetes, smoking and drinking status did not show significant associations with carotid atherosclerosis. In conclusion, low HDL-C and advanced hypertension were significant correlates of carotid atherosclerosis for middle-aged Japanese men with multiple risk factors.

Correlation between Progetto Cuore risk score and early cardiovascular damage in never treated subjects

Background

Global cardiovascular risk is a new approach which allows the physicians to quantitate the prognosis of the patients. It is therefore possible that a score, based on the major cardiovascular risk factors, is correlated with some degree of cardiovascular anatomic damage. Since this hypothesis has been demonstrated with the Framingham risk score, we decided to verify it using another score (Progetto Cuore risk score), which is probably more precise in a european low-risk population, such as the italian one.

Methods

We studied 84 italian caucasian subjects (50 males and 34 females) with elevated blood pressure and/or dyslipidemia plus other possible cardiovascular risk factors.

The subjects have never been treated for these reasons. The following evaluations were performed: history, clinical and laboratory determinations, echocardiogram, carotid echodoppler.

Results

The recruited people were on the whole characterized by a low cardiovascular risk, as confirmed by the low scores of the Progetto Cuore. Simple linear regression analysis showed significant associations between some parameters of early cardiovascular damage (left ventricular mass, intima-media thickness, and an integrated measure of both the carotid wall thickness and the presence of a plaque, called Carotid score) and some predictors. The highest significance was found between the cardiovascular structural results and the Progetto Cuore score. In a multivariate regression analysis our model, which included factors potentially linked to the cardiovascular anatomic changes, demonstrated that the Carotid score was significantly associated with age, sex and pulse pressure; intima-media thickness with the same factors and, in addition, with the body mass index; left ventricular mass with sex, pulse pressure and body mass index.

Conclusion

Our paper confirms previous studies about the association between a comprehensive risk score and signs of early cardiovascular damage. A temporally limited exposure to cardiovascular risk factors, in particular to blood pressure, is already able to induce significant changes in both the heart structure and the vascular wall. Also in a european low-risk population the use of a cardiovascular risk score program, such as the Progetto Cuore in Italy, allows a quite precise estimation of the possible cardiovascular damage.

C-reactive protein and the metabolic syndrome correlate differently with carotid atherosclerosis between men and women in a Taiwanese community

Little is known about the role of C-reactive protein (CRP) and metabolic syndrome (MetS) in carotid atherosclerosis among Chinese. In the present cross-sectional study, we examined this relationship and emphasized the sex differences in 456 men and 354 women aged 39 years and older who participated in a community-based cohort study in Taiwan. These participants received measurements for high-sensitivity CRP and ultrasound examinations for common carotid artery intima-media thickness (IMT) and extracranial carotid artery plaques. Metabolic syndrome was defined by the US National Cholesterol Education Program Adult Treatment Panel III criteria. The women had higher median CRP (1.3 vs 1.1 mg/L) and MetS prevalence than the men (58.8 vs 34.2%). Thicker IMT was associated with MetS in women (multivariate-adjusted odds ratio [OR], 2.07; 95% confidence interval, 1.04-4.11) but not in men. Compared with participants with CRP <1 mg/L, men with CRP >3 mg/L had an elevated OR with the presence of plaque (OR, 1.99; 95% confidence interval, 1.10-3.61), but not women. Compared with men with CRP <1 mg/L and no MetS, individuals with MetS and CRP level >3 mg/L were 2.2 times (P = .046) more likely to have artery plaque. In conclusion, thicker IMT is related to MetS in women, whereas the presence of plaque is associated with elevated CRP in men, and this association is enhanced by MetS.

Association between hemodynamics in the common carotid artery and severity of carotid atherosclerosis in patients with essential hypertension

BACKGROUND

Carotid intima-media thickness (IMT) and plaque burden evaluated by B-mode ultrasound have been used as relevant indicators for carotid atherosclerosis. This study was aimed to investigate the relationship between hemodynamic parameters in the common carotid artery (CCA) and the severity of carotid atherosclerosis in untreated hypertensive patients.

METHODS

Carotid IMT and plaque burden were evaluated in bilateral CCA, bifurcations, external and internal carotid arteries using duplex ultrasound in 80 untreated hypertensive patients. The patients were divided into four groups according to plaque burden. Hemodynamic parameters of CCA, including peak and mean circumferential wall tension (CWT), tensile stress (TS), wall shear stress (WSS), and Young's elastic modulus (YEM), were calculated after measurements of internal diameter (ID), IMT, and peak and mean flow velocities of CCA. Arterial stiffness was also assessed using the brachial-ankle pulse wave velocity (baPWV).

RESULTS

Age, pulse pressure, creatinine, carotid IMT, and mean TS were shown to have significant differences among the four plaque groups (P < 0.05). Peak CWT and peak TS were also shown to have marginal differences. In univariate analysis, the peak and mean CWT and TS were significantly correlated with plaque score. Stepwise multiple regression analysis showed that carotid IMT, age, and peak CWT were independently associated with plaque score.

CONCLUSIONS

These results suggest that the CWT and TS of the CCA are associated with the severity of carotid atherosclerosis in untreated hypertensive patients. Hence, the hemodynamics of vessels may contribute to the plaque burden of low-resistance arteries.

Does the constellation of risk factors with and without abdominal adiposity associate with different cardiovascular mortality risk?

AIMS

To evaluate whether the metabolic syndrome (MetS) defined by the International Diabetes Federation (IDF) criteria, which has abdominal adiposity as a mandatory element, predicts cardiovascular disease (CVD) mortality better than the cluster of other IDF-defined abnormalities not including abdominal adiposity.

METHODS

Data from nine European population-based studies, including 7782 men and 7739 women (aged 30-89 years), with a median follow-up of 8.55 years, were jointly analyzed. Hazard ratios for CVD mortality were calculated with Cox regression models.

RESULTS

In total, 41% of the men and 38% of the women had the IDF MetS. Individuals with the IDF MetS were by definition more obese and had a higher prevalence of diabetes than non-obese subjects with > or = 2 IDF abnormalities; whereas non-obese men with > or = 3 factors had more atherogenic lipid profiles. Multivariate adjusted hazard ratio for CVD death in men and women with the IDF MetS was 2.44 (1.69-2.98) and 2.32 (1.27-4.23); in non-obese men with 2 and > or = 3 factors the hazard ratio was 1.60 (1.12-2.30) and 2.44 (1.62-3.66), respectively, and in non-obese women with 2 factors the hazard ratio was 2.41 (1.09-5.33).

CONCLUSIONS

The cluster of the CVD risk factors predicted CVD mortality regardless of the presence or absence of the abdominal adiposity. Inclusion of abdominal adiposity as a prerequisite will miss those non-obese individuals who have increased CVD mortality.

Metabolic syndrome components in african-americans and European-american patients and its relation to coronary artery disease

A number of factors used to define the metabolic syndrome (MS) differ between African-American and European-American patients, which raises the question whether the individual constellation of MS components would impact cardiovascular risk. Our objectives were to assess the association between the MS and coronary artery disease (CAD) across ethnicities and to explore whether the constellation used to define the syndrome would impact any such association. We studied the distribution of the MS and its relation to CAD in 304 European-American subjects and 224 African-American subjects undergoing diagnostic coronary angiography. The overall prevalence of the MS in European-American and African-American subjects were 65.5% and 49.1%, respectively. Compared with European-American subjects, the lipid components of the syndrome were less frequent among African-American subjects (44% vs 64% [p <0.001] for high-density lipoprotein [HDL] cholesterol and 21% vs 51% [p <0.001] for triglyceride, respectively). The prevalence of CAD was significantly higher in subjects with MS across ethnicity (71.1% of European-American subjects and 56.6% of African-American subjects, p = 0.017 and p = 0.046, respectively). Multiple regression analyses demonstrated an association of blood pressure and HDL cholesterol with CAD among European-American subjects, which remained significant taking other risk factors into account (r(2) = 0.542, p <0.001). In conclusion, presence of CAD was more common among subjects with MS independently of ethnicity. Of the MS components, blood pressure was associated with CAD among European-American subjects. Although our findings may not be directly extrapolated to the population at large, they illustrate the importance of a high-risk metabolic environment as a cardiovascular risk factor.

Serum ghrelin and carotid atherosclerosis in older Japanese people with metabolic syndrome

Ghrelin may play a role in the development of atherosclerosis. However, the effect of serum ghrelin on carotid intima-media thickness (cIMT) (well-established as a surrogate marker to atherosclerosis) in metabolic syndrome (MS), particularly among relatively older subjects, has still not been thoroughly investigated. A total of 101 subjects >60 years of age (mean age, 72.3 years) with MS were enrolled in the study to investigate the relationship between serum total ghrelin and B-mode ultrasonographic cIMT levels. There were significantly positive correlations between cIMT and both age and systolic BP, but cIMT was significantly inversely correlated to ghrelin levels. In the multiple regression analysis for cIMT adjusted by other measured parameters, ghrelin was a significant and independent factor along with age and systolic BP. These findings suggest that decreased ghrelin levels may be related to carotid atherosclerosis among older subjects with MS.

Metabolic syndrome and early-onset coronary artery disease: is the whole greater than its parts?

OBJECTIVES

We sought to examine the association between the metabolic syndrome (MetS) (defined both by the 2001 National Cholesterol Educational Program Adult Treatment Panel III [ATP-III] definition and the American Heart Association/National Heart, Lung and Blood Institute [AHA/NHLBI] revision incorporating the lower threshold for impaired fasting glucose [IFG]) and early-onset coronary artery disease (CAD).

BACKGROUND

The impact of MetS on premature CAD has not been studied extensively. Lowering the threshold to define the IFG component (from 110 to 100 mg/dl) and the value of the syndrome as a whole versus its individual components are subjects of intense debate.

METHODS

We performed a case-control study with 393 early-onset CAD subjects (acute myocardial infarction, angina with > or =50% stenosis, or coronary revascularization) in men under age 46 years or women under age 56 years and 393 control subjects individually matched for gender, age, and race/ethnicity.

RESULTS

By conditional logistic regression, presence of ATP-III MetS without diabetes (adjusted odds ratio [adj-OR] 4.9; 95% confidence interval [CI] 3.4 to 8.0) and with diabetes (adj-OR 8.0, 95% CI 4.39 to 14.6) was a strong independent determinant of early-onset CAD. Using the AHA/NHLBI revision, these ORs became slightly stronger. However, neither definition of MetS remained significantly associated with early-onset CAD in multivariate models adjusting for individual components.

CONCLUSIONS

The presence of MetS imparts a high risk of early-onset clinical CAD, but the prognostic information associated with the syndrome is not greater than the sum of its parts.

Metabolic syndrome and progression of atherosclerosis among middle-aged US adults

Metabolic syndrome, indicated by insulin resistance/hyperinsulinemia, obesity, central obesity, atherogenic dyslipidemia, and hypertension, contributes to atherosclerotic cardiovascular disease. However, it is controversial whether the indicators of metabolic syndrome are related to subclinical atherosclerosis collectively or individually. Whether there is any gender-based difference in the mechanisms of metabolic syndrome-induced atherosclerosis progression is also unknown. Two models were compared in this study. Model 1 assumes that a latent factor, metabolic syndrome per se, impacts subclinical atherosclerosis (collective effects model); Model 2 assumes the effect of the syndrome is mediated through its indicators (individual effects model). Data were obtained from the Los Angeles Atherosclerosis Study. The cohort consists of 573 adults (age, 40-60 years) who were asymptomatic for cardiovascular disease. Subclinical atherosclerosis was assessed by measuring common carotid artery intima-media thickness (CCA-IMT) using B-mode ultrasound. Three examinations were completed at 1.5-year intervals from 1995-1999. The analyses were performed with SAS 8.2 and AMOS 4.0. The results showed that atherogenic effects of metabolic syndrome were mediated through its indicators; there were gender-based differences in the mechanisms of metabolic syndrome-induced atherosclerosis. Central obesity was significantly associated with the baseline IMT for men only, whereas triglycerides were significantly associated with the progression of IMT for women only. Systolic blood pressure was significantly associated with the baseline and progression for both men and women. However, fasting insulin was not found to be significantly associated with the baseline and progression of IMT in the multivariate model, although it was significantly associated with other components of metabolic syndrome.