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

Is the prevalence of risk factors, clinical presentations and severity of coronary artery diseases (CAD) in patients with very early and premature CAD are different from mature CAD patients?: A registry- based cross-sectional study

Introduction

The present study aims to compare the risk factors, clinical presentation, and severity of coronary artery involvement in young compared to elderly CAD patients to assess the cardiovascular health status for better disease management and control of these specific patients.

Methods

This registry-based cross-sectional study was conducted using Coronary Angiography and Angioplasty Registry (CAAR) patients in east of Tehran, Iran. The data were extracted from 330 patients with confirmed CAD recorded by the CAAR during July 2021 to August 2023.

Results

The majority of patients in MCAD (68.2%) and VECAD (80%) were male, while the majority of PCAD patients were female (51.8%). Among PCAD patients, the prevalence of diabetes (38.1%) was higher than in other groups. The presence of IHD history in the father (38.1%) and mother (26.3%) was higher in the VECAD group. The mean total cholesterol, LDL, and LDL/HDL ratio were higher in the VECAD group. Among MCAD group (75.4%) compared to PCAD (58.1%) and VECAD (47.2%) groups, the multi-vessel disease was more common.MCAD patients had the highest median Gensini score compared to PCAD and VECAD patients. Also, in male compared to female the mean Gensini score was higher by 8 units (ß = 8.26, 95%CI = 0.24, 16.28).

Conclusion

Modifiable risk factors in young CAD patients are common. High LDL-C levels and smoking were the common modifiable CVD risk factors in young patients, indicating the significant role of these traditional risk factors in early atherosclerosis development alongside inheritable risk-factors such as positive family history that were more common in young CAD patients. While, the severity of coronary artery involvement in individuals with MCAD was higher, but the priority of involvement based on the type of vessel was almost the same in all CAD groups.

RNA Sequencing of Whole Blood in Premature Coronary Artery Disease: Identification of Novel Biomarkers and Involvement of T Cell Imbalance

Serum biomarkers were explored based on the peripheral blood gene expression profiles of premature coronary artery disease (PCAD). RNA sequencing (RNA-Seq) was used to detect PCAD-specific differentially expressed genes (DEGs). Quantitative real-time polymerase chain reaction (RT-PCR) was used to validate the most significant DEGs, and enzyme-linked immunosorbent assay (ELISA) was utilized to quantify the effect on corresponding serum proteins. Fifty-nine PCAD-specific DEGs were identified. Functional analysis showed positive regulation of T cell-mediated cytotoxicity, regulation of T cell-mediated immunity, and the regulation of alpha-beta T cell proliferation which were enriched in PCAD. RT-PCR validated the significant difference in the expression of BAG6, MUC5B, and APOA2 between PCAD and late-onset coronary artery disease (LCAD) patients. ELISA validation showed serum MUC5B increased dramatically in PCAD when compared to LCAD. Our study found T cells contribute to the occurrence of PCAD, and the inflammatory factor MUC5B may be a novel serum marker in PCAD patients.

Premature coronary heart disease complicated with hypertension in hospitalized patients: Incidence, risk factors, cardiovascular-related comorbidities and prognosis, 2008-2018

Background

The clinical characteristics and risk factors of all-cause mortality in young hospitalized patients with comorbid coronary heart disease and hypertension (CAD + HT) are not well-characterized.

Method

A total of 2288 hospitalized CAD patients (age<45 years) with or without hypertension in the Chinese PLA General Hospital from August 5, 2008 to June 22, 2018 were conducted. The risk factors of all-cause mortality were estimated in young CAD + HT patients by COX models.

Results

The overall prevalence of hypertension in young CAD patients was 50.83% (n = 1163). CAD + HT patients had older age, higher heart rate, BMI, uric acid, triglyceride and lower level of eGFR and HDL-C than CAD patients (P < 0.05). The proportion of cardiovascular-related comorbidities (including obesity, diabetes mellitus, hyperuricemia and chronic kidney disease [CKD]) in the CAD + HT group was significantly higher than that in CAD group (P < 0.0001). The risk of all-cause mortality was higher in CAD + HT patients, although after adjusting for all covariates, there was no significant difference between the two groups. Furthermore, CKD (HR, 3.662; 95% CI, 1.545-8.682) and heart failure (HF) (HR, 3.136; 95%CI, 1.276-7.703) were associated with an increased risk of all-cause mortality and RAASi (HR, 0.378; 95%CI, 0.174-0.819) had a beneficial impact in CAD + HT patients.

Conclusions

Hypertension was highly prevalent in young CAD patients. Young CAD + HT patients had more cardiovascular metabolic risk factors, more cardiovascular-related comorbidities and higher risk of all-cause mortality. CKD and HF were the risk factors, while RAASi was a protective factor, of all-cause mortality in CAD + HT patients.

Aldehyde dehydrogenase 2 rs671 a/A Genotype is Associated with an Increased Risk of Early Onset Coronary Artery Stenosis

Background

The role of aldehyde dehydrogenase 2 (ALDH2) in cardiovascular diseases has been gradually studied. However, it is unclear whether ALDH2 polymorphism is associated with the risk of early onset (onset age ≤55 years old in men and ≤65 years old in women) coronary artery stenosis (CAS). The association between ALDH2 single nucleotide polymorphism (SNP) rs671 and risk in patients with early onset CAS was investigated in this study.

Methods

The study included 213 early onset CAS patients and 352 individuals without CAS were set as controls. The ALDH2 rs671 polymorphism was genotyped by polymerase chain reaction (PCR) - microarray. Differences in ALDH2 rs671 genotypes and alleles between patients and controls were compared. Multiple logistic regression analysis was performed after adjusting for gender, body mass index (BMI), smoking history, drinking history, and diabetes mellitus to assess the relationship between ALDH2 rs671 genotypes and early onset CAS risk.

Results

The frequency of the ALDH2 rs671 G/G genotype was lower in the early onset CAS patients (43.7% vs 55.3%, p=0.007) than that in the controls. The frequency of the ALDH2 rs671 A allele was higher (32.9% vs 25.0%) than that in the controls (p=0.005). After adjusting for other confounding factors, multivariate logistic regression showed that ALDH2 rs671 A/A genotype (A/A vs G/G: odds ratio (OR) 2.508, 95% confidence interval (CI): 1.130-5.569, p=0.024), overweight (BMI≥24.0 vs 18.5-23.9: OR 5.047, 95% CI: 3.275-7.777, p<0.001), history of smoking (yes vs no: OR 2.813, 95% CI: 1.595-4.961, p<0.001), and diabetes mellitus (yes vs no: OR 2.191, 95% CI: 1.397-3.437, p=0.001) were the independent risk factors of early onset CAS.

Conclusion

In men ≤55 years old and women ≤65 years old, individuals with ALDH2 rs671 A/A genotype, overweight (BMI ≥24.0 kg/m2), smoking history, and diabetes mellitus increased risk of developing CAS.

Modifiable and Non-Modifiable Risk Factors for Premature Coronary Heart Disease (PCHD): Systematic Review and Meta-Analysis

AIM

We aimed to compare the prevalence of modifiable and non-modifiable coronary heart disease (CHD) risk factors among those with premature CHD and healthy individuals.

METHODS

PubMed, CINAHL, Embase, and Web of Science databases were searched (review protocol is registered in PROSPERO CRD42020173216). The quality of studies was assessed using the National Heart, Lung and Blood Institute tool for cross-sectional, cohort and case-control studies. Meta-analyses were performed using Review Manager 5.3. Effect sizes for categorical and continuous variables, odds ratio (OR) and mean differences (MD)/standardised mean differences (SMD) with 95% confidence intervals (CI) were reported.

RESULTS

A total of n=208 primary studies were included in this review. Individuals presenting with premature CHD (PCHD, age ≤65 years) had higher mean body mass index (MD 0.54 kg/m2, 95% CI 0.24, 0.83), total cholesterol (SMD 0.27, 95% CI 0.17, 0.38), triglycerides (SMD 0.50, 95% CI 0.41, 0.60) and lower high-density lipoprotein cholesterol (SMD 0.79, 95% CI: -0.91, -0.68) compared with healthy individuals. Individuals presenting with PCHD were more likely to be smokers (OR 2.88, 95% CI 2.51, 3.31), consumed excessive alcohol (OR 1.40, 95% CI 1.05, 1.86), had higher mean lipoprotein (a) levels (SMD 0.41, 95% CI 0.28, 0.54), and had a positive family history of CHD (OR 3.65, 95% CI 2.87, 4.66) compared with healthy individuals. Also, they were more likely to be obese (OR 1.59, 95% CI 1.32, 1.91), and to have had dyslipidaemia (OR 2.74, 95% CI 2.18, 3.45), hypertension (OR 2.80, 95% CI 2.28, 3.45), and type 2 diabetes mellitus (OR 2.93, 95% CI 2.50, 3.45) compared with healthy individuals.

CONCLUSION

This meta-analysis confirms current knowledge of risk factors for PCHD, and identifying these early may reduce CHD in young adults.

Mutated CYP17A1 promotes atherosclerosis and early-onset coronary artery disease

BACKGROUND

Coronary artery disease (CAD) is a multi-factor complex trait and is heritable, especially in early-onset families. However, the genetic factors affecting the susceptibility of early-onset CAD are not fully characterized.

METHODS

In the present study, we identified a rare nonsense variant in the CYP17A1 gene from a Chinese Han family with CAD. To validate the effect of this variation on atherosclerosis and early-onset coronary artery disease, we conducted studies on population, cells, and mice.

RESULTS

The mutation precisely congregated with the clinical syndrome in all the affected family members and was absent in unaffected family members and unrelated controls. Similar to the human phenotype, the CYP17A1-deficient mice present the phenotype of metabolic syndrome with hypertension, increased serum glucose concentration, and presentation of central obesity and fatty liver. Furthermore, CYP17A1 knockout mice or CYP17A1 + ApoE double knockout mice developed more atherosclerotic lesions than wild type (WT) with high fat diary. In cell models, CYP17A1 was found to be involved in glucose metabolism by increasing glucose intake and utilization, through activating IGF1/mTOR/HIF1-α signaling way, which was consistent in CYP17A1 knockout mice with impaired glucose tolerance and insulin resistance.

CONCLUSIONS

Through our study of cells, mice and humans, we identified CYP17A1 as a key protein participating in the pathophysiology of the atherosclerotic process and the possible mechanism of CYP17A1 C987X mutation induced atherosclerosis and early-onset CAD involving glucose homeostasis regulation was revealed. Video Abstract.

Combination of exercise and GLP-1 receptor agonist treatment reduces severity of metabolic syndrome, abdominal obesity, and inflammation: a randomized controlled trial

BACKGROUND

Identifying and reducing cardiometabolic risks driven by obesity remains a healthcare challenge. The metabolic syndrome is associated with abdominal obesity and inflammation and is predictive of long-term risk of developing type 2 diabetes and cardiovascular disease in otherwise healthy individuals living with obesity. Therefore, we investigated the effects of adherent exercise, a glucagon-like peptide 1 receptor agonist (GLP-1 RA), or the combination on severity of metabolic syndrome, abdominal obesity, and inflammation following weight loss.

METHODS

This was a randomized, double-blinded, placebo-controlled trial. During an 8-week low-calorie diet (800 kcal/day), 195 adults with obesity and without diabetes lost 12% in body weight. Participants were then evenly randomized to four arms of one-year treatment with: placebo, moderate-to-vigorous exercise (minimum of 150 min/week of moderate-intensity or 75 min/week of vigorous-intensity aerobic physical activity or an equivalent combination of both), the GLP-1 RA liraglutide 3.0 mg/day, or a combination (exercise + liraglutide). A total of 166 participants completed the trial. We assessed the prespecified secondary outcome metabolic syndrome severity z-score (MetS-Z), abdominal obesity (estimated as android fat via dual-energy X-ray absorptiometry), and inflammation marker high-sensitivity C-reactive protein (hsCRP). Statistical analysis was performed on 130 participants adherent to the study interventions (per-protocol population) using a mixed linear model.

RESULTS

The diet-induced weight loss decreased the severity of MetS-Z from 0.57 to 0.06, which was maintained in the placebo and exercise groups after one year. MetS-Z was further decreased by liraglutide (- 0.37, 95% CI - 0.58 to - 0.16, P < 0.001) and the combination treatment (- 0.48, 95% CI - 0.70 to - 0.25, P < 0.001) compared to placebo. Abdominal fat percentage decreased by 2.6, 2.8, and 6.1 percentage points in the exercise, liraglutide, and combination groups compared to placebo, respectively, and hsCRP decreased only in the combination group compared with placebo (by 43%, P = 0.03).

CONCLUSION

The combination of adherent exercise and liraglutide treatment reduced metabolic syndrome severity, abdominal obesity, and inflammation and may therefore reduce cardiometabolic risk more than the individual treatments. Trial registration EudraCT number: 2015-005585-32, ClinicalTrials.gov: NCT04122716.

Sex-Specific Risk Factors Associated With First Acute Myocardial Infarction in Young Adults

IMPORTANCE

An increasing proportion of people in the US hospitalized for acute myocardial infarction (AMI) are younger than 55 years, with the largest increase in young women. Effective prevention requires an understanding of risk factors associated with risk of AMI in young women compared with men.

OBJECTIVES

To assess the sex-specific associations of demographic, clinical, and psychosocial risk factors with first AMI among adults younger than 55 years, overall, and by AMI subtype.

DESIGN, SETTING, AND PARTICIPANTS

This study used a case-control design with 2264 patients with AMI, aged 18 to 55 years, from the VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) study and 2264 population-based controls matched for age, sex, and race and ethnicity from the National Health and Nutrition Examination Survey from 2008 to 2012. Data were analyzed from April 2020 to November 2021.

EXPOSURES

A wide range of demographic, clinical, and psychosocial risk factors.

MAIN OUTCOMES AND MEASURES

Odds ratios (ORs) and population attributable fractions (PAF) for first AMI associated with demographic, clinical, and psychosocial risk factors.

RESULTS

Of the 4528 case patients and matched controls, 3122 (68.9%) were women, and the median (IQR) age was 48 (44-52) years. Seven risk factors (diabetes [OR, 3.59 (95% CI, 2.72-4.74) in women vs 1.76 (1.19-2.60) in men], depression [OR, 3.09 (95% CI, 2.37-4.04) in women vs 1.77 (1.15-2.73) in men], hypertension [OR, 2.87 (95% CI, 2.31-3.57) in women vs 2.19 (1.65-2.90) in men], current smoking [OR, 3.28 (95% CI, 2.65-4.07) in women vs 3.28 (2.65-4.07) in men], family history of premature myocardial infarction [OR, 1.48 (95% CI, 1.17-1.88) in women vs 2.42 (1.71-3.41) in men], low household income [OR, 1.79 (95% CI, 1.28-2.50) in women vs 1.35 (0.82-2.23) in men], hypercholesterolemia [OR, 1.02 (95% CI, 0.81-1.29) in women vs 2.16 (1.49-3.15) in men]) collectively accounted for the majority of the total risk of AMI in women (83.9%) and men (85.1%). There were significant sex differences in risk factor associations: hypertension, depression, diabetes, current smoking, and family history of diabetes had stronger associations with AMI in young women, whereas hypercholesterolemia had a stronger association in young men. Risk factor profiles varied by AMI subtype, and traditional cardiovascular risk factors had higher prevalence and stronger ORs for type 1 AMI compared with other AMI subtypes.

CONCLUSIONS AND RELEVANCE

In this case-control study, 7 risk factors, many potentially modifiable, accounted for 85% of the risk of first AMI in young women and men. Significant differences in risk factor profiles and risk factor associations existed by sex and by AMI subtype. These findings suggest the need for sex-specific strategies in risk factor modification and prevention of AMI in young adults. Further research is needed to improve risk assessment of AMI subtypes.

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.

The combination of insulin resistance and visceral adipose tissue estimation improves the performance of metabolic syndrome as a predictor of type 2 diabetes

AIMS

To assess the performance of metabolic syndrome as a predictor of type 2 diabetes in a model that also includes both a measure of insulin resistance and a metabolic score for visceral fat, and to propose a novel metabolic syndrome definition.

METHODS

In a prospective Metabolic Syndrome Cohort (n=6143), we evaluated improvements in type 2 diabetes risk prediction using International Diabetes Federation-defined and Adult Treatment Panel III-defined metabolic syndrome, after inclusion in the model of updated homeostatic model assessment of insulin resistance and a metabolic score for visceral fat. We also developed a modified metabolic syndrome construct, 'MS-METS', which used the metabolic score for visceral fat instead of waist circumference to evaluate improved predictive performance for risk of developing type 2 diabetes.

RESULTS

Participants who had metabolic syndrome as defined by both the Adult Treatment Panel III and the International Diabetes Federation criteria had a higher risk of type 2 diabetes compared to participants who did not meet these criteria. Addition of updated homeostatic model assessment of insulin resistance and metabolic score for visceral fat to both metabolic syndrome definitions increased predictive performance for type 2 diabetes risk. Homeostatic model assessment of insulin resistance was the only additional predictor of type 2 diabetes in participants without metabolic syndrome. Conversely, in participants with metabolic syndrome, the use of the metabolic score for visceral fat was the stronger added predictor for type 2 diabetes. When evaluating participants using the MS-METS definition we observed the largest improvement in predictive ability for type 2 diabetes risk and a significant reduction in risk overestimation compared to evaluation using metabolic syndrome defined according to the International Diabetes Federation and Adult Treatment Panel III criteria alone.

CONCLUSION

Inclusion of updated homeostatic model assessment of insulin resistance and metabolic score for visceral fat increases performance of metabolic syndrome in prediction of type 2 diabetes. Assessment of insulin resistance could be more useful than conventional metabolic syndrome and assessment of visceral adipose tissue could be more useful in people with metabolic syndrome. Metabolic syndrome as defined using our modified MS-METS construct improved the accuracy of type 2 diabetes prediction.

Characteristics of culprit lesions in young patients with metabolic syndrome and classic cardiovascular risk factors

The association between cardiovascular risk factors (CVRFs) and characteristics of coronary plaque in young patients has remained to be fully elucidated. Therefore, the present study sought to determine the association between CVRFs and phenotypes of culprit coronary plaques revealed by optical coherence tomography (OCT) in young patients with stable coronary heart disease (CHD) and acute coronary syndrome (ACS). OCT imaging pullback was performed at corresponding sites on 123 lesions in 123 young patients (age, 36±7 years), including those with stable CHD and ACS. Patients with analyzable OCT images were classified as having thin-cap fibroatheromas (TCFAs), plaque rupture, macrophage accumulation, calcified nodule, vasa vasorum, cholesterol crystal and erosion. TCFAs were more prevalent in patients with metabolic syndrome (MetS) than in those without MetS (P=0.020). Plaque rupture was more common in smokers than in non-smokers (P=0.002). Multivariate analysis indicated that MetS was independently associated with TCFAs (P=0.041) and smoking was independently associated with plaque rupture (P=0.006). Young patients with MetS were demonstrated to have more extensive TCFAs and young smokers had a higher prevalence of culprit plaque rupture.

Menopause improves the predictive value of common cardiovascular risk scores in women with premature coronary artery disease

OBJECTIVE

Menopause, particularly its early stage (≤3 years from onset), may be an important risk factor for premature coronary artery disease. The objective of the study was to assess whether the addition of the presence of menopause in women with premature coronary artery disease could improve the predictive value of the Atherosclerotic Cardiovascular Disease risk estimator and the Systematic COronary Risk Evaluation model.

METHODS

The case-control study included 307 women with coronary artery disease aged 55 or less, and 347 age-matched controls without coronary artery disease. Diagnostic accuracy parameters were evaluated for traditional risk models versus those enriched with menopausal status. Early and late postmenopausal periods were defined as ≤3 and >3 years from the onset of menopause, respectively.

RESULTS

Only the addition of the presence of the early postmenopausal stage to the 10-year Atherosclerotic Cardiovascular Disease risk classes resulted in significantly increased c-statistics from 0.66 (95% confidence interval [CI] 0.62-0.7) to 0.705 (95%CI 0.66-0.75) (P = 0.0003) and an increase of accuracy from 61.3% to 63.8% (P = 0.0025).Adding the presence of early postmenopause to the Systematic COronary Risk Evaluation risk classes also resulted in significantly increased c-statistics from 0.59 (95% CI 0.55-0.63) to 0.641 (95%CI 0.6-0.68) (P = 0.0024) and an increase of accuracy from 64.1% versus 57.5% (P = 0.001).

CONCLUSION

Adding the early menopausal period may significantly improve the predictive value of the 10-year Atherosclerotic Cardiovascular Disease risk score and the Systematic COronary Risk Evaluation model in women with premature coronary artery disease.

Perceived stress correlates with visceral obesity and lipid parameters of the metabolic syndrome: A systematic review and meta-analysis

BACKGROUND

Perceived stress has been proposed as a risk factor of metabolic syndrome. However, correlations between perceived stress and parameters of the metabolic syndrome have not been properly analyzed despite extensive research data on the topic. Our current meta-analysis aimed to examine the mutual association between perceived stress of patients and parameters of metabolic syndrome.

METHODS

This systematic review has been registered on the PROSPERO database (registration number CRD42017055293). Eligible studies divided participants based on their stress level or on the presence of metabolic syndrome. They reported at least one parameter of the metabolic syndrome or the stress level of the participants measured with some stress scale. Data from 17 articles met the eligibility criteria and were included. Random effects model with the DerSimonian and Laird weighting methods was applied. I-squared indicator and Q test were performed to assess heterogeneity.

RESULTS

Although the majority of individual studies failed to demonstrate correlations between stress and their analyzed parameters of metabolic syndrome, our meta-analysis showed a significant association between stress and BMI [average effect size (ES) with 95% confidence interval (95%CI), ES = 0.65, 95%CI 0.16, 1.14), waist circumference (ES = 1.84 cm, 95%CI 0.79, 2.89) and serum triglyceride level (ES = 7.52 mg/dl, 95%CI 0.07, 14.96). Additional analysis confirmed effects of stress on serum HDL (ES = - 1.699 mg/dl, 95%CI -2.966, -0.432) and diastolic blood pressure (ES = 1.04 mmHg, 95%CI 0.18, 1.89). No correlations were found for fasting glucose or systolic blood pressure. No association between metabolic syndrome and stress level of patients was detected either.

CONCLUSION

The potentially key role of visceral obesity in the association between perceived stress and dyslipidemia or diastolic blood pressure are discussed together with potential moderators (e.g. gender-differences, variations in stress assessment and metabolic syndrome criteria) that may explain the inconsistent, contradictory results of the individual studies.

Cardiovascular Health Status and Metabolic Syndrome in Adults Living in a Transition European Country: Findings from a Population-Based Study

BACKGROUND AND PURPOSE

There are only a few published studies on the relationship between cardiovascular health (CVH) status as proposed by the American Heart Association and the metabolic syndrome (MetS) in persons with cardiovascular disease (CVD). The aim of this study was to assess the prevalence of CVH and MetS and their correlation in the adult population of the Republic of Srpska, Bosnia and Herzegovina, in order to evaluate which set of cardiovascular risk factors (low or medium CVH status and MetS), or the combination of both, is a better predictor for the occurrence of CVD.

METHODS

We included 3601 adults (aged ≥25 years) from the Republic of Srpska National Health Survey 2010. CVH status was evaluated according to the American Heart Association criteria, whereas MetS was defined using the criteria of the National Cholesterol Education Program's Adult Treatment Panel III.

RESULTS

The prevalence of low or medium CVH status and MetS is significantly higher in participants who had experienced CVD than in those free of CVD. Our study showed that predictors for CVD occurrence were presence of MetS (odds ratio 3.61, 95% confidence intervals 2.14-6.07) and presence of both sets of cardiovascular risk factors in the same person (odds ratio 4.23, 95% confidence intervals 1.50-11.93).

CONCLUSION

Our results suggest that presence of both sets of cardiovascular risk factors (low or medium CVH status and MetS) is the strongest predictor of CVD. Identification of individuals with cardiovascular risk factors may provide opportunities to intervene earlier and can help reduce the risk of developing CVD.

Oxidative status and reduced glutathione levels in premature coronary artery disease and coronary artery disease

Identifying patients at risk of developing premature coronary artery disease (PCAD) which occurs at age below 45 years old and constitutes approximately 7-10% of coronary artery disease (CAD) worldwide remains a problem. Oxidative stress has been proposed as a crucial step in the early development of PCAD. This study was conducted to determine the oxidative status of PCAD in comparison to CAD patients. PCAD (<45 years old) and CAD (>60 years old) patients were recruited with age-matched controls (n = 30, each group). DNA damage score, plasma malondialdehyde (MDA) and protein carbonyl content were measured for oxidative damage markers. Antioxidants such as erythrocyte glutathione (GSH), oxidised glutathione (GSSG), and glutathione peroxidase activity (GPx), superoxide dismutase (SOD) and catalase (CAT) were also determined. DNA damage score and protein carbonyl content were significantly higher in both PCAD and CAD when compared to age-matched controls while MDA level was increased only in PCAD (p<.05). In contrast, GSH, GSH/GSSG ratio, α-tocotrienol isomer, and GPx activity were significantly decreased, but only in PCAD when compared to age-matched controls. The decrease in GSH was associated with PCAD (OR = 0.569 95%CI [0.375 - 0.864], p = .008) and cut-off values of 6.69 μM with areas under the ROC curves (AUROC) 95%CI: 0.88 [0.80-0.96] (sensitivity of 83.3%; specificity of 80%). However, there were no significant differences in SOD and CAT activities in all groups. A higher level of oxidative stress indicated by elevated MDA levels and low levels of GSH, α-tocotrienol and GPx activity in patients below 45 years old may play a role in the development of PCAD and has potential as biomarkers for PCAD.

Effects of metabolic syndrome on aortic pulse wave velocity

BACKGROUND

The purpose of this study was to compare the value and evaluate the validity of non-invasive methods for the detection of vascular stiffness in never-treated individuals with metabolic syndrome (MetS).

METHODS

A total of 59 subjects (mean age, 60 ± 12 years; male:female = 35:24) were enrolled in the study and were categorized into the positive MetS (MetS[+]: N = 32) and negative group (MetS[-]: N = 27), according to the parameters set by the National Cholesterol Education Program's Adult Treatment Panel III. Pulse wave velocity (PWV) of the aorta, arm, and leg, Framingham risk score (FRS), ankle-brachial index (ABI), and carotid intima-media thickness (IMT) for vascular aging were measured for the two groups.

RESULTS

Aortic PWV (PWVaor) was significantly higher in MetS(+) than MetS(-) group (7.0 ± 1.4 m/s vs. 8.4 ± 1.6 m/s, p < 0.01), while ABI was significantly lower in MetS(+) than MetS(-) group (1.2 ± 0.1 vs. 1.1 ± 0.2, p = 0.03), respectively. FRS was significantly higher in MetS(+) than MetS(-) group (11 ± 5 vs. 14 ± 4, p = 0.05). The both mean IMT was higher in MetS(+) than MetS(-) group (right: 0.94 ± 0.20 mm vs. 0.81 ± 0.20 mm, p = 0.03; left: 0.93 ± 0.20 mm vs. 0.79 ± 0.20 mm, p = 0.03, respectively). For predicting the probability of the presence of MetS, PWVaor was an independent tool (p = 0.04; odds ratio, 1.88; 95% confidence interval, 1.03 to 3.42) and a cut-off value of PWVaor of 7.4 m/s showed a sensitivity of 66.7% and a specificity of 47.6%.

CONCLUSIONS

We suggest that PWVaor, combined with traditional tools, can play an important role as a complementary or alternative tool for the detection of vascular stiffness in never-treated individuals with MetS.

Newer perspectives of coronary artery disease in young

Coronary artery disease (CAD) occurring in less than 45 years of age is termed as young CAD. Recent studies show a prevalence of 1.2% of CAD cases in this age group. Ethnic wise south Asians especially Indians are more vulnerable to have CAD in young age group with a prevalence of 5% to 10%. Conventional risk factors such as smoking, diabetes, hypertension, obesity and family history seems to be as important as in older CAD subjects. But the prevalence of these risk factors seems to vary in younger subjects. By far the most commonly associated risk factor is smoking in young CAD. Several genes associated with lipoprotein metabolism are now found to be associated with young CAD like cholesterol ester transfer protein (CETP) gene, hepatic lipase gene, lipoprotein lipase gene, apo A1 gene, apo E gene and apo B. Biomarkers such as lipoprotein (a), fibrinogen, D-dimer, serum Wnt, gamma glutamyl transferase, vitamin D2 and osteocalcin are seems to be associated with premature CAD in some newer studies. In general CAD in young has better prognosis than older subjects. In terms of prognosis two risk factors obesity and current smoking are associated with poorer outcomes. Angiographic studies shows predominance of single vessel disease in young CAD patients. Like CAD in older person primary and secondary prevention plays an important role in prevention of new and further coronary events.

Flow Mediated Dilatation, Carotid Intima Media Thickness, Ankle Brachial Pressure Index and Pulse Pressure in Young Male Post Myocardial Infarction Patients in India

INTRODUCTION

Due to increase in Coronary Artery Disease (CAD) at a younger age, we should try to diagnose atherosclerotic process and population at risk, at the earliest. Flow Mediated Dilatation (FMD), Carotid Intima-Media Thickness (CIMT) and Ankle-Brachial Pressure Index (ABI) are probable markers for early atherosclerosis and may be useful in coronary risk stratification.

AIM

To compare and correlate the FMD, CIMT, ABI and Pulse Pressure (PP) in young male patients of Myocardial Infarction (MI) with age and sex matched healthy controls.

MATERIALS AND METHODS

Eighty male patients of MI aged ≤45 years, who presented to the Cardiac Care Unit and Department of Medicine of Guru Teg Bahadur Hospital, Delhi, India, from November 2010 to April 2012 were recruited consecutively for this case control study and same number of age and sex matched healthy controls were also analyzed. Six weeks after MI, FMD of the brachial artery, intima media thickness of carotid artery, ABPI and PP were measured in the cases and compared with healthy controls.

RESULTS

The FMD was lower among young patients of MI than controls (p<0.001). CIMT was higher among cases than controls (p=0.001). ABI was lower among cases than controls (p<0.001). Compared to controls, PP was higher among cases (p=0.001). In all subjects, a negative correlation between FMD and CIMT (r=-0.220, p=0.005) and a positive correlation between FMD and ABPI (r=0.304, p<0.001) was found. A statistically significant negative correlation was found between endothelial dependent FMD and PP among cases and control groups (r=-0.209, p=0.007).

CONCLUSION

Biophysical parameters were deranged in young post MI patients. Majority of our young male patients fell in low risk Framingham risk score but still they manifested with CAD. Despite six weeks of treatment among young male patients of MI, various biophysical parameters were still deranged.

Metabolic Syndrome: An Evolving Clinical Construct

Metabolic syndrome (MetS), a clustering of metabolic risk factors, identifies individuals at increased risk of diabetes and cardiovascular disease (CVD). Measurement of waist circumference, high-density lipoprotein-cholesterol, triglycerides, blood pressure and fasting blood glucose are easily obtained in the clinic. At any level of low-density lipoprotein-cholesterol, presence of MetS increases the risk of adverse CVD outcomes including bothatherosclerotic CVD and atrial fibrillation. The MetS construct should focus the clinician on recommending behavioral lifestyle modification as this improves all of its components. The challenge, however, has been the lack of a standardized approach to achieve effective and sustained lifestyle modification in clinical practice. We briefly review various approaches useful to the clinician in counseling such patients. These include group lifestyle programs and emerging mobile technology. Technology alone may not be sufficient, but as an adjunct has the promise to improve low rates of behavioral change currently seen with traditional programs.

The clinical value of metabolic syndrome and risks of cardiometabolic events and mortality in the elderly: the Rotterdam study

Background

To evaluate the clinical value of metabolic syndrome based on different definitions [American Heart Association/National Heart, Lung and Blood Institute (AHA/NHLBI), International Diabetes Federation (IDF) and European Group for the Study of Insulin Resistance (EGIR)] in middle-aged and elderly populations.

Methods

We studied 8643 participants from the Rotterdam study (1990–2012; mean age 62.7; 57.6 % female), a large prospective population-based study with predominantly elderly participants. We performed cox-proportional hazards models for different definitions, triads within definitions and each separate component for the risk of incident type 2 diabetes mellitus, coronary heart disease, stroke, cardiovascular- and all-cause mortality.

Results

In our population of 8643 subjects, metabolic syndrome was highly prevalent (prevalence between 19.4 and 42.4 %). Metabolic syndrome in general was associated with incident type 2 diabetes mellitus (median follow-up of 6.8 years, hazard ratios 3.13–3.78). The associations with coronary heart disease (median follow-up of 7.2 years, hazard ratios 1.08–1.32), stroke (median follow-up of 7.7 years, hazard ratios 0.98–1.32), cardiovascular mortality (median follow-up of 8.2 years, ratios 0.95–1.29) and all-cause mortality (median follow-up of 8.7 years, hazard ratios 1.05–1.10) were weaker. AHA/NHLBI- and IDF-definitions showed similar associations with clinical endpoints compared to the EGIR, which was only significantly associated with incident type 2 diabetes mellitus. All significant associations disappeared after correcting metabolic syndrome for its individual components.

Conclusions

Large variability exists between and within definitions of the metabolic syndrome with respect to risk of clinical events and mortality. In a relatively old population the metabolic syndrome did not show an additional predictive value on top of its individual components. So, besides as a manner of easy identification of high risk patients, the metabolic syndrome does not seem to add any predictive value for clinical practice.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0387-4) contains supplementary material, which is available to authorized users.

Establishment and application of a new diagnostic definition of metabolic syndrome in the Shantou region of southern China

The existing definitions of metabolic syndrome (MetS) may not be fully appropriate for the Shantou population because of ethnic and regional differences. We sought to establish a 95% multivariate medical reference range (MMRR) model for diagnosing MetS in Shantou adults and to evaluate the prevalence of MetS by the MMRR, JCDCG (the Chinese Guidelines), and International Diabetes Federation (IDF) criteria. A total of 4,580 participants were recruited in Shantou, southern China. We developed a MMRR model based on the combinatorial indicatrixes method for three categorized indicatrixes. According to the developed MMRR criteria, men (women) in Shantou have MetS by meeting 3 or more of the following: waist circumference ≥89 (81) cm; triglycerides level ≥1.73 (1.64) mmol/L; high-density lipoprotein cholesterol level ≤1.07 (1.05) mmol/L; blood pressure ≥138/89 (136/85) mmHg; and fasting plasma glucose ≥5.8 (5.7) mmol/L. The agreement of the MMRR with JCDCG and IDF criteria was "substantial" (both κ > 0.68), but the recommended reference values and proportion of individual components of MetS defined by the 3 criteria differed. The population-based MMRR criteria may be appropriate for diagnosing MetS in Shantou population and the model might be useful for generalization to other geographic regions.

Early Myocardial Repolarization Heterogeneity Is Detected by Magnetocardiography in Diabetic Patients with Cardiovascular Risk Factors

Multi-channel magnetocardiography (MCG) is a sensitive technique to map spatial ventricular repolarization with high resolution and reproducibility. Spatial ventricular repolarization heterogeneity measured by MCG has been shown to accurately detect and localize myocardial ischemia. Here, we explored whether these measurements correlated with cardiovascular risk factors in patients with type 2 diabetes. Two hundreds and seventy-seven type 2 diabetic patients without known coronary artery disease (CAD) and arrhythmia were recruited consecutively from the outpatient clinic of National Taiwan University Hospital. The spatially distributed QTc contour maps were constructed with 64-channel MCG using the superconducting quantum interference device (SQUID) system. Indices of myocardial repolarization heterogeneity including the smoothness index of QTc (SI-QTc) and QTc dispersion were derived and analyzed for association with conventional cardiovascular risk factors. SI-QTc correlated strongly with the QTc dispersion (r = 0.70, p <0.0001). SI-QTc was significantly higher in patients with presence of metabolic syndrome in comparison to those without metabolic syndrome (8.56 vs. 7.96 ms, p = 0.02). In univariate correlation analyses, QTc dispersion was associated with smoking status (average 79.90, 83.83, 86.51, and 86.00 ms for never smokers, ex-smokers, current smokers reporting less than 10 cigarettes daily, and current smoker reporting more than 10 cigarettes daily, respectively, p = 0.03), body weight (r = 0.15, p = 0.01), and hemoglobin A1c (r = 0.12, p = 0.04). In stepwise multivariate regression analyses, QTc dispersion was associated with smoking (p = 0.02), body weight (p = 0.04), total cholesterol levels (p = 0.05), and possibly estimated glomerular filtration rate (p = 0.07). In summary, spatial heterogeneity of myocardial repolarization measured by MCG is positively associated cardiovascular risk factors including adiposity, smoking, and total cholesterol levels.

Race and ethnicity, obesity, metabolic health, and risk of cardiovascular disease in postmenopausal women

Background

It is unclear whether obesity unaccompanied by metabolic abnormalities is associated with increased cardiovascular disease risk across racial and ethnic subgroups.

Methods and Results

We identified 14 364 postmenopausal women from the Women's Health Initiative who had data on fasting serum lipids and serum glucose and no history of cardiovascular disease or diabetes at baseline. We categorized women by body mass index (in kg/m²) as normal weight (body mass index 18.5 to <25), overweight (body mass index 25 to <30), or obese (body mass index ≥30) and by metabolic health, defined first as the metabolic syndrome (metabolically unhealthy: ≥3 metabolic abnormalities) and second as the number of metabolic abnormalities. We used Cox proportional hazards regression to assess associations between baseline characteristics and cardiovascular risk. Over 13 years of follow-up, 1101 women had a first cardiovascular disease event (coronary heart disease or ischemic stroke). Among black women without metabolic syndrome, overweight women had higher adjusted cardiovascular risk than normal weight women (hazard ratio [HR] 1.49), whereas among white women without metabolic syndrome, overweight women had similar risk to normal weight women (HR 0.92, interaction P=0.05). Obese black women without metabolic syndrome had higher adjusted risk (HR 1.95) than obese white women (HR 1.07; interaction P=0.02). Among women with only 2 metabolic abnormalities, cardiovascular risk was increased in black women who were overweight (HR 1.77) or obese (HR 2.17) but not in white women who were overweight (HR 0.98) or obese (HR 1.06). Overweight and obese women with ≤1 metabolic abnormality did not have increased cardiovascular risk, regardless of race or ethnicity.

Conclusions

Metabolic abnormalities appeared to convey more cardiovascular risk among black women.

Reduced systemic microvascular density and reactivity in individuals with early onset coronary artery disease

OBJECTIVE

This study sought to test whether patients with early-onset coronary artery disease (EOCAD, n=30) showed systemic microvascular rarefaction and endothelial dysfunction in comparison to age- and sex-matched healthy controls (CTL, n=30), as evaluated by skin video-capillaroscopy.

METHODS

Functional capillary density (FCD) was defined as the number of spontaneously perfused capillaries per square millimeter of skin area and assessed by high-resolution intra-vital color microscopy in the dorsum of the middle phalanx. Capillary recruitment (capillary reserve) was evaluated using post-occlusive reactive hyperemia (PORH) after arm ischemia for 3min.

RESULTS

The mean capillary density at rest was significantly reduced in patients with EOCAD compared to controls (CTL 95±20 and EOCAD 80±18capillaries/mm(2), P=0.0040). During PORH, capillary density was also markedly reduced in EOCAD patients (CTL 96±18 and EOCAD 71±20capillaries/mm(2), P<0.0001). Moreover, the capillary density in EOCAD patients was significantly reduced during PORH (EOCAD at rest 80±19 and EOCAD during PORH 71±20capillaries/mm(2), P=0.0073).

CONCLUSIONS

Patients with EOCAD presented systemic capillary rarefaction and impaired microvascular endothelial function. Thus, the early detection of these microvascular alterations in young adults at an increased risk of coronary artery disease could be useful as a surrogate marker of subclinical atherosclerosis.

The relationship between obesity and coronary artery disease

Obesity continues to be a growing issue in the United States, with an estimated prevalence of 72 million people. There are major health implications associated with obesity, including its relationship with hypertension, diabetes mellitus type 2, metabolic syndrome, and dyslipidemia, all independent risk factors for coronary artery disease (CAD). Despite the increased risk of developing CAD, in recent years an "obesity paradox" has been described in which moderately obese individuals with established cardiovascular disease, including CAD, appear to have mortality similar to their normal-weight counterparts. This review examines the relationship between obesity and CAD, including the increased risk of hypertension, diabetes mellitus, metabolic syndrome, and dyslipidemia, along with a discussion of the obesity paradox and the benefits of weight reduction.

Predisposing factors to premature coronary artery disease in young (age ≤ 45 years) smokers: a single center retrospective case control study from India

Introduction: The role of the conventional risk factors in premature coronary artery disease (CAD) after eliminating the confounding variability of smoking has not been evaluated. This study was conducted to identify role of traditional risk factors in smokers with premature CAD.

Methods: The case records of patients presenting acutely with premature CAD during the period 2007-2010 were analyzed retrospectively. Age, sex and smoking matched controls were selected from same time period. Data records were obtained for family history, alcohol, waist size, blood pressure, hypertension, blood sugar, lipid profile and presence of cutaneous markers for both groups and analyzed using statistical software.

Results: 234 smokers with CAD and 122 smokers without CAD were included in groups 1 and 2, respectively. The patients in group 1 had significantly increased prevalence of hypertension, diabetes mellitus, metabolic syndrome, dyslipidemia and central obesity. There was no difference in prevalence of family history of CAD, arcus juvenilis and baldness. We found statistically significant association of hypertension, DM and metabolic syndrome in young smokers with premature acute CAD in Indian population as compared to young smokers without CAD.

Conclusion: In young smokers, presence of hypertension, central obesity, diabetes mellitus and metabolic syndrome identifies a subset at increased risk for future acute CAD requiring more rigorous follow up and treatment.

Impact of metabolic syndrome components on incident stroke subtypes: a Chinese cohort study

Limited evidence is available on the risk differences in the development of stroke subtypes in relation to particular clustering patterns of the metabolic syndrome (MetS) components. A follow-up study of a Chinese cohort involving 10,292 individuals was performed to assess the roles of cluster patterns of the MetS components in the prediction of incident stroke subtypes. During follow-up, there were 161 incident cases of ischemic strokes and 41 incident cases of hemorrhagic strokes. Among MetS components, only the hypertensive trait was associated with significantly elevated risks of both ischemic and hemorrhagic strokes. Furthermore, MetS with hypertension as components was associated with increased risk of ischemic and hemorrhagic strokes (adjusted hazards ratio (95% confidence interval) was 2.96 (1.94-4.50) and 2.93 (1.25-6.90), respectively) as compared with those who had neither hypertension nor MetS. Notably, as the number of the MetS components increased, the risk of ischemic stroke significantly and dose-dependently increased. This implies a cumulative effect of MetS components in elevating the risk of ischemic stroke. These findings suggest that MetS comprises heterogenous clusters with respect to the risk of developing the subtype of stroke.

Treating the metabolic syndrome

The metabolic syndrome (MS), a cluster of metabolic abnormalities with insulin resistance as its central component, is increasing in prevalence and is associated with an increased risk of cardiovascular disease and Type 2 diabetes mellitus (T2DM). Current evidence supports an aggressive intervention approach that comprises lifestyle modification in conjunction with drug treatment of the MS components. Healthier eating and regular exercise greatly reduce waistline and body mass index, lower blood pressure and improve lipid profile. Lifestyle modification has been proven to prevent T2DM development. Nevertheless, appropriate treatment of MS components often requires pharmacologic intervention with insulin-sensitizing agents, such as metformin and thiazolidinediones, while statins and fibrates, or angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers are the first-line lipid-modifying or antihypertensive drugs. Only severely obese patients require specific drug treatments. Very often, drug combinations will be necessary to manage multiple risk factors. As we progress in the understanding of the pathophysiology of the MS, new targets for therapies will probably be identified and new treatments will prove to be even more efficacious than those currently available for the management of this life-threatening condition.

The impact of obesity on risk factors and prevalence and prognosis of coronary heart disease-the obesity paradox

Obesity is associated with a host of cardiovascular risk factors and its prevalence is rising rapidly. Despite strong evidence that obesity predisposes to the development and progression of coronary heart disease (CHD), numerous studies have shown an inverse relationship between various measures of obesity (most commonly body mass index) and outcomes in established CHD. In this article we review the evidence surrounding the ≪obesity paradox≫ in the secondary care of CHD patients and the CHD presentations where a paradox has been found. Finally we discuss the impact of cardiorespiratory fitness and a number of mechanisms which may offer potential explanations for this puzzling phenomenon.

Human C-reactive protein gene polymorphism and metabolic syndrome are associated with premature coronary artery disease

The aim of this study was to investigate the association between C-reactive protein (CRP) gene polymorphism and metabolic syndrome (MetS) with premature coronary artery disease (PCAD). 116 patients with PCAD (58 with MetS and 58 without MetS) and 119 controls were included in the study. CRP gene +1059 G>C polymorphism was analyzed by polymerase chain reaction. Serum hs-CRP was measured using high-sensitivity enzyme-linked immunosorbent assay. Carriers of C allele of the CRP +1059 G>C polymorphism had 3.37 fold increased risk to develop MetS in patients with PCAD. In addition CRP gene and hs-CRP levels were independent risk factors for PCAD and MetS. The present study provides new evidence that the presence of CRP +1059 G>C polymorphism and hs-CRP levels are independent determinants of PCAD and MetS in Egyptians. The results of our study suggest a synergistic effect of CRP C allele with classical risk factors such as hypertension, obesity, dyslipidemia and MetS.

Determinants of developing diabetes mellitus and vascular complications in patients with impaired fasting glucose

AIMS

To detect the risk factors of diabetes mellitus (DM) and cardiovascular complications in subjects with impaired fasting glucose (IFG).

MATERIALS AND METHODS

One hundred and twenty three subjects with proved IFG in Zanjan Healthy Heart Study (2002-2003) were recalled and participated in this study (2009-2010). Demographic and laboratoryinformation of the participants were collected.Ischemic heart disease (IHD) was assessed by the exercise tolerance test (ETT). All the subjects with abnormal ETT or documented past history of IHD confirmed by angiographic evaluation. Ophthalmic complications including cataract, glaucoma, and diabetic retinopathy were estimated by an ophthalmologist.

RESULTS

Incidence of DM was 19.5%. All the diabetic and pre-diabetic patients had at least one of the other components of metabolic syndrome. Obesity (P: 0.04, OR: 1.8, 95%CI: 1.2-9) and low physical activity (P < 0.001, OR: 9.6, 95%CI: 3.4-32) were the only independent prognostic risk factors for progression to DM in patients with IFG. Total incidence of IHD was 14.6% and had a strong correlation with sex (P: 0.01, OR: 1.8, 95%CI: 1.2-1.5), age (P < 0.001, OR: 23, 95%CI: 2.1-67) and cigarette smoking (P < 0.001, OR: 36.5, 95%CI: 3.9-337). Non-proliferative diabetic retinopathy was shown in 2 (1.6%) subjects who were all women.

CONCLUSION

Obesity and low physical activity are the main factors of developing DM and its macrovascular complications in subjects with IFG.

Is the metabolic syndrome a "small baby" syndrome?: the bogalusa heart study

BACKGROUND

Metabolic syndrome has been called a "small baby syndrome," but other analyses suggest that postnatal growth is more important than birthweight, or that large babies are also at risk. The aim of this analysis was to examine whether there was a relationship between both low and high birthweight and metabolic syndrome, using multiple definitions of metabolic syndrome, and to determine whether this relationship varied by body size across the life course.

METHODS

Data from the Bogalusa Heart Study, a study of cardiovascular disease in children and young adults, were linked to birth certificate data. Metabolic syndrome was defined by the National Cholesterol Education Program, the International Diabetes Foundation, and the World Health Organization (WHO) definition. Small-for-gestational-age (SGA) was defined as birthweight <10(th) percentile by sex for gestational age and large-for-gestational-age (LGA) as birthweight >90(th) percentile. Birthweight-for-gestational-age was also examined as a continuous predictor. Chi-squared tests and logistic regression were used to examine the relationship between birth size and metabolic syndrome.

RESULTS

Higher birthweight-for-gestational-age was associated with a reduced risk of metabolic syndrome, especially by the WHO definition. After adjustment for body mass index (BMI), categorized birthweight was associated with metabolic syndrome, with the protective associations with LGA being stronger than the positive associations with SGA. Among the individual components of metabolic syndrome, higher waist circumference was associated with both SGA and LGA after BMI was controlled for. Effects of SGA and BMI at any age were largely independent rather than interactive.

CONCLUSIONS

SGA is associated with some, but not all, components of metabolic syndrome. The relationship between SGA and metabolic syndrome is partially confounded by later BMI.

Waist circumference and metabolic syndrome: the risk for silent coronary artery disease in males

BACKGROUND

Waist circumference (WC) is a component used to define metabolic syndrome. However, its role as an independent predictor of silent coronary artery disease (CAD), above its contribution to metabolic syndrome, remains unknown.

METHODS

Male veterans without known CAD, undergoing cardiac stress testing for indications other than typical angina or its equivalent, were evaluated for the presence of silent CAD. High WC and metabolic syndrome were defined per the revised National Cholesterol Education Program (NCEP-R) and the International Diabetes Federation (IDF) criteria.

RESULTS

Data on 1,071 patients (age 61±11 years) were analyzed retrospectively. On multivariable logistic regression analysis [odds ratio (OR), 95% confidence interval (CI), P value), a WC ≥94 cm (1.42, 1.04-1.93; P=0.026), metabolic syndrome by NCEP-R (1.73, 1.29-2.33; P<0.0001), and metabolic syndrome by IDF (1.57, 1.17-2.11; P=0.003) were independent predictors of silent CAD. When comparing patients meeting criteria for metabolic syndrome defined by either NCEP-R or IDF, the prevalence of silent CAD was not statistically different (P=0.86). The prevalence of silent CAD associated with a high WC was not inferior to that seen between silent CAD and metabolic syndrome as defined by either criterion. Last, among patients with metabolic syndrome defined by NCEP-R, those with a high WC as a defining component of metabolic syndrome had a higher prevalence of silent CAD (30% vs. 20%; P=0.026).

CONCLUSION

A WC ≥94 cm in males is independently associated with an increased prevalence of silent CAD. In patients with metabolic syndrome, this prevalence is increased by the presence of high WC.

Genomewide Association Studies in Cardiovascular Disease—An Update 2011

BACKGROUND

Genomewide association studies have led to an enormous boost in the identification of susceptibility genes for cardiovascular diseases. This review aims to summarize the most important findings of recent years.

CONTENT

We have carefully reviewed the current literature (PubMed search terms: “genome wide association studies,” “genetic polymorphism,” “genetic risk factors,” “association study” in connection with the respective diseases, “risk score,” “transcriptome”).

SUMMARY

Multiple novel genetic loci for such important cardiovascular diseases as myocardial infarction, hypertension, heart failure, stroke, and hyperlipidemia have been identified. Given that many novel genetic risk factors lie within hitherto-unsuspected genes or influence gene expression, these findings have inspired discoveries of biological function. Despite these successes, however, only a fraction of the heritability for most cardiovascular diseases has been explained thus far. Forthcoming techniques such as whole-genome sequencing will be important to close the gap of missing heritability.

The metabolic syndrome--from insulin resistance to obesity and diabetes

In today's society with the escalating levels of obesity, diabetes, and cardiovascular disease, the metabolic syndrome is receiving considerable attention and is the subject of much controversy. Greater insight into the mechanism(s) behind the syndrome may improve our understanding of how to prevent and best manage this complex condition.

Metabolic syndrome: definitions and controversies

Metabolic syndrome (MetS) is a complex disorder defined by a cluster of interconnected factors that increase the risk of cardiovascular atherosclerotic diseases and diabetes mellitus type 2. Currently, several different definitions of MetS exist, causing substantial confusion as to whether they identify the same individuals or represent a surrogate of risk factors. Recently, a number of other factors besides those traditionally used to define MetS that are also linked to the syndrome have been identified. In this review, we critically consider existing definitions and evolving information, and conclude that there is still a need to develop uniform criteria to define MetS, so as to enable comparisons between different studies and to better identify patients at risk. As the application of the MetS model has not been fully validated in children and adolescents as yet, and because of its alarmingly increasing prevalence in this population, we suggest that diagnosis, prevention and treatment in this age group should better focus on established risk factors rather than the diagnosis of MetS.

A bivariate genome-wide approach to metabolic syndrome: STAMPEED consortium

OBJECTIVE The metabolic syndrome (MetS) is defined as concomitant disorders of lipid and glucose metabolism, central obesity, and high blood pressure, with an increased risk of type 2 diabetes and cardiovascular disease. This study tests whether common genetic variants with pleiotropic effects account for some of the correlated architecture among five metabolic phenotypes that define MetS. RESEARCH DESIGN AND METHODS Seven studies of the STAMPEED consortium, comprising 22,161 participants of European ancestry, underwent genome-wide association analyses of metabolic traits using a panel of ∼2.5 million imputed single nucleotide polymorphisms (SNPs). Phenotypes were defined by the National Cholesterol Education Program (NCEP) criteria for MetS in pairwise combinations. Individuals exceeding the NCEP thresholds for both traits of a pair were considered affected. RESULTS Twenty-nine common variants were associated with MetS or a pair of traits. Variants in the genes LPL, CETP, APOA5 (and its cluster), GCKR (and its cluster), LIPC, TRIB1, LOC100128354/MTNR1B, ABCB11, and LOC100129150 were further tested for their association with individual qualitative and quantitative traits. None of the 16 top SNPs (one per gene) associated simultaneously with more than two individual traits. Of them 11 variants showed nominal associations with MetS per se. The effects of 16 top SNPs on the quantitative traits were relatively small, together explaining from ∼9% of the variance in triglycerides, 5.8% of high-density lipoprotein cholesterol, 3.6% of fasting glucose, and 1.4% of systolic blood pressure. CONCLUSIONS Qualitative and quantitative pleiotropic tests on pairs of traits indicate that a small portion of the covariation in these traits can be explained by the reported common genetic variants.

The impact of early menopause on risk of coronary artery disease (PREmature Coronary Artery Disease In Women--PRECADIW case-control study)

BACKGROUND

Despite improved understanding of atherothrombosis pathophysiology, risk factors associated with premature coronary artery disease (CAD) in women are poorly recognized.

DESIGN AND METHODS

A single-centre, case-control study comprised 323 women (less than 55 years) with established CAD, enrolled between April 2005 and January 2008, and 347 age-matched healthy women selected from the Multi-Center All-Polish Health Survey. We aimed to assess the relationship of menopause and premature CAD.

RESULTS

In multivariate analysis smoking, parental history of premature CVD, diabetes, menopause and hypertension were the strongest risk markers for premature CAD with ORs (95% CI): 3.83 (2.52-5.82); 3.08 (1.85-5.14); 2.89 (1.59-5.23); 2.82 (1.91-4.19); 2.39 (1.16-3.54). The most significant association was found for early postmenopause in a model including the early and late stage of postmenopause (≤ and >3 years of its onset), with OR 4.55 (95% CI 2.82-7.35), higher than other risk factors. The receiver operating characteristic (ROC) curves area revealed a significant increase from 0.81 in that model that included traditional risk factors and parental premature CVD to 0.85 after addition of the early and late stage of postmenopause.

CONCLUSIONS

We have shown that smoking and early postmenopausal stage (≤3 years) are the most important determinants of premature CAD followed by parental CVD, diabetes and hypertension.

Right coronary wall CMR in the older asymptomatic advance cohort: positive remodeling and associations with type 2 diabetes and coronary calcium

BACKGROUND

Coronary wall cardiovascular magnetic resonance (CMR) is a promising noninvasive approach to assess subclinical atherosclerosis, but data are limited in subjects over 60 years old, who are at increased risk. The purpose of the study was to evaluate coronary wall CMR in an asymptomatic older cohort.

RESULTS

Cross-sectional images of the proximal right coronary artery (RCA) were acquired using spiral black-blood coronary CMR (0.7 mm resolution) in 223 older, community-based patients without a history of cardiovascular disease (age 60-72 years old, 38% female). Coronary measurements (total vessel area, lumen area, wall area, and wall thickness) had small intra- and inter-observer variabilities (r = 0.93~0.99, all p < 0.0001), though one-third of these older subjects had suboptimal image quality. Increased coronary wall thickness correlated with increased coronary vessel area (p < 0.0001), consistent with positive remodeling. On multivariate analysis, type 2 diabetes was the only risk factor associated with increased coronary wall area and thickness (p = 0.03 and p = 0.007, respectively). Coronary wall CMR measures were also associated with coronary calcification (p = 0.01-0.03).

CONCLUSIONS

Right coronary wall CMR in asymptomatic older subjects showed increased coronary atherosclerosis in subjects with type 2 diabetes as well as coronary calcification. Coronary wall CMR may contribute to the noninvasive assessment of subclinical coronary atherosclerosis in older, at-risk patient groups.

Nutrition patterns and metabolic syndrome: a need for action in young adults (French Nutrition and Health Survey - ENNS, 2006-2007)

OBJECTIVE

The objective of this study was to investigate the relationship between adherence to French diet and physical activity recommendations and metabolic syndrome (MetS) risk.

METHODS

18-74-year-old subjects who underwent dietary assessment and health examination in the 2006-2007 French Nutrition and Health Survey (Etude Nationale Nutrition Santé, ENNS 2006-2007) were included in the analyses (n=1608). Quintiles of PNNS-GS, the score measuring adherence to French recommendations, were generated. The prevalence of overall MetS risk and separate components across quintiles of PNNS-GS was estimated by adjusted logistic regressions. Interactions were searched for between PNNS-GS and sex, age and currently used medication.

RESULTS

The PNNS-GS was inversely associated with overall MetS risk in subjects not taking antidiabetic, antihypertensive or lipid-lowering medication (12.8% in the lowest quintile vs. 4.6% in the highest PNNS-GS quintile; P<0.01). This was true in 18-49-year-old subjects (10.0% vs. 1.7%, P<0.01), but not in 50-74-year-olds (23.8% vs. 11.2%; P=0.15). In 18-49-year-old adults, including those taking such medication, the HDL component was associated with PNNS-GS (22.1% vs. 7.9%; P<0.01).

CONCLUSION

Improvement in diet and physical activity in line with recommendations could be effective in young adults for MetS prevention so as to decrease the risk of cardiovascular disease in France.

Farnesoid X receptor activation improves erectile dysfunction in models of metabolic syndrome and diabetes

The metabolic syndrome (MetS) is an insulin-resistant state characterized by a cluster of cardiovascular risk factors, including abdominal obesity, hyperglycemia, elevated blood pressure and combined dyslipidemia. In this review, we discuss the potential of farnesoid X receptor (FXR) agonists in the treatment of erectile dysfunction (ED), a multifactorial disorder often comorbid with MetS. FXR not only regulates lipid and glucose homeostasis but also influences endothelial function and atherosclerosis, suggesting a regulatory role for this hormone nuclear receptor in the cardiovascular complications associated with the MetS, including ED. MetS induces ED via several mechanisms, and in particular through endothelial dysfunction in penile vessels. In a high-fat diet rabbit model of MetS, a 3-month treatment with the potent and selective FXR agonist INT-747 restores endothelium-dependent relaxation in isolated cavernous tissue, normalizing responsiveness to acetylcholine and to electrical field stimulation. Accordingly, eNOS expression in the penis is greatly up-regulated by INT-747 treatment. Experiments in a rat model of chemically-induced type 1 diabetes further demonstrate that INT-747 treatment preserves erectile function induced by electrical stimulation of the cavernous nerve. These results add a new facet to the pleiotropic activities mediated by FXR, and reveal novel beneficial effects of FXR activation with potential clinical relevance. This article is part of a Special Issue entitled: Translating nuclear receptors from health to disease.

Association of genetic variants with myocardial infarction in Japanese individuals with or without metabolic syndrome

The etiology of metabolic syndrome (MetS) is highly complex, with both genetic and environmental factors being thought to play an important role. Although MetS has been recognized as a risk factor for myocardial infarction (MI), the genetic risk for MI in individuals with or without MetS has remained uncharacterized. We examined a possible association of genetic variants with MI in individuals with or without MetS separately. The study population comprised 4,424 individuals, including 1,918 individuals with MetS (903 subjects with MI and 1,015 controls) and 2,506 individuals without MetS (499 subjects with MI and 2,007 controls). The 150 polymorphisms examined in the present study were selected by genome-wide association studies of MI and ischemic stroke with the use of Affymetrix GeneChip Human Mapping 500K Array Set. Initial screening by the Chi-square test revealed that the C→T polymorphism (rs1794429) of LRPAP1, the A→G polymorphism (rs12373237) of LAMA3 and the A→G polymorphism (rs3782257) of NCOR2 were significantly (false discovery rate of <0.05) associated with MI for individuals with MetS, and that the C→G polymorphism (rs13051704) of TFF1 was significantly related to MI for individuals without MetS. Subsequent multivariable logistic analysis with adjustment for covariates revealed that rs1794429 of LRPAP1 (recessive model; P=0.0218; odds ratio=0.71) and rs3782257 of NCOR2 (dominant model; P=0.0057; odds ratio=1.94) were significantly associated with MI among individuals with MetS, and that rs13051704 of TFF1 (additive model; P=0.0100; odds ratio=0.55) was significantly associated with MI among individuals without MetS. The genetic variants that confer susceptibility to MI differ between individuals with or without MetS. Stratification of subjects according to the presence or absence of MetS may thus be important for personalized prevention of MI based on genetic information.