Impact of metabolic syndrome and its individual components on the presence and severity of angiographic coronary artery disease

Introduction to ion transport and membrane interactions in vascular health and disease

Cardiovascular disease is on the rise, partially due to the continued increase in metabolic syndrome. Advances in basic research on vascular ion transport have the potential to provide targets for therapeutic interventions. Vascular specificity, which includes different vascular beds having different characteristics and the macro- vs. microvasculature, is a vitally important variable in characterization of ion transport. At the cellular level, targeted fluorescent biosensors for Ca²⁺, super-resolution microscopy, and organelle patch clamp electrophysiology enable more detailed studies. The "MetS/diabetes milieu" includes increased and decreased insulin, and increased glucose, increased LDL/HDL cholesterol and triglycerides, and increased blood pressure. The duration and severity of MetS/diabetes components certainly affect the vascular phenotype and ion transport and membrane interactions. A combination of in vivo animal models and in vitro cell models to study ion transport in MetS/diabetes conditions is optimal. Gene editing and selective pharmacological tools should be used after or in conjunction with characterization of ion transport in vascular health and disease phenotypes. This is critical to determining the causal role of Ca²⁺ signaling in modulation of vascular phenotype. The ion transport and membrane interactions that are measured are typically only a snapshot in time in these dynamic processes occurring over the progression of health and disease. It is imperative that this concept be considered in the planning of long-term studies of vascular disease, ion transport experiments, and interpretation of the data. Future directions for our contributors' research will advance the field.

Multiphasic changes in smooth muscle Ca2+ transporters during the progression of coronary atherosclerosis

Ischemic heart disease due to macrovascular atherosclerosis and microvascular dysfunction is the major cause of death worldwide and the unabated increase in metabolic syndrome is a major reason why this will continue. Intracellular free Ca²⁺ ([Ca²⁺]_i) regulates a variety of cellular functions including contraction, proliferation, migration, and transcription. It follows that studies of vascular Ca²⁺ regulation in reductionist models and translational animal models are vital to understanding vascular health and disease. Swine with metabolic syndrome (MetS) develop the full range of coronary atherosclerosis from mild to severe disease. Intravascular imaging enables quantitative measurement of atherosclerosis in vivo, so viable coronary smooth muscle (CSM) cells can be dispersed from the arteries to enable Ca²⁺ transport studies in native cells. Transition of CSM from the contractile phenotype in the healthy swine to the proliferative phenotype in mild atherosclerosis was associated with increases in SERCA activity, sarcoplasmic reticulum Ca²⁺, and voltage-gated Ca²⁺ channel function. In vitro organ culture confirmed that SERCA activation induces CSM proliferation. Transition from the proliferative to a more osteogenic phenotype was associated with decreases in all three Ca²⁺ transporters. Overall, there was a biphasic change in Ca²⁺ transporters over the progression of atherosclerosis in the swine model and this was confirmed in CSM from failing explanted hearts of humans. A major determinant of endolysosome content in human CSM is the severity of atherosclerosis. In swine CSM endolysosome Ca²⁺ release occurred through the TPC2 channel. We propose a multiphasic change in Ca²⁺ transporters over the progression of coronary atherosclerosis.

Intracellular Ca2+ Dysregulation in Coronary Smooth Muscle Is Similar in Coronary Disease of Humans and Ossabaw Miniature Swine

Intracellular free Ca2+ ([Ca2+]i) dysregulation occurs in coronary smooth muscle (CSM) in atherosclerotic coronary artery disease (CAD) of metabolic syndrome (MetS) swine. Our goal was to determine how CAD severity, arterial structure, and MetS risk factors associate with [Ca2+]i dysregulation in human CAD compared to changes in Ossabaw miniature swine. CSM cells were dispersed from coronary arteries of explanted hearts from transplant recipients and from lean and MetS swine with CAD. CSM [Ca2+]i elicited by Ca2+ influx and sarcoplasmic reticulum (SR) Ca2+ release and sequestration was measured with fura-2. Increased [Ca2+]i signaling was associated with advanced age and a greater media area in human CAD. Decreased [Ca2+]i signaling was associated with a greater number of risk factors and a higher plaque burden in human and swine CAD. Similar [Ca2+]i dysregulation exhibited in human and Ossabaw swine CSM provides strong evidence for the translational relevance of this large animal model.

25-hydroxyvitamin D levels are inversely related to metabolic syndrome risk profile in northern Chinese subjects without vitamin D supplementation

BACKGROUND

The comparatively low 25 hydroxyvitamin D [25(OH)D] levels have been reported in patients with metabolic syndrome (MetS). Herein we investigated the cross-sectional and longitudinal relationships between serum 25(OH)D levels and MetS risk profile in northern middle-aged Chinese subjects without vitamin D supplementation.

METHODS

A cohort of 211 participants including 151 MetS patients and 60 controls at 20-69 years of age were enrolled from suburban Beijing, China. The recruited MetS patients were subjected to diet and exercise counselling for 1-year. All subjects at baseline and MetS patients after intervention underwent clinical evaluations.

RESULTS

Serum 25(OH)D levels were significantly decreased in MetS patients. 25(OH)D levels were inversely related to MetS score, fasting blood glucose (FBG) and triglyceride-glucose index (TyG) after adjusting for cofounders (all P < 0.05). Participants in the lowest tertile of 25(OH)D levels had increased odds for MetS (P = 0.045), elevated FBG (P = 0.004) in all subjects, and one MetS score gain in MetS patients (P = 0.005). Longitudinally, the metabolic statuses as well as 25(OH)D levels of MetS patients were significantly improved (all P < 0.05), and the increase of 25(OH)D levels were inversely related to MetS scores, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), FBG, and TyG, while positively related to high-density lipoprotein cholesterol (HDL-C) after adjusting for confounders.

CONCLUSIONS

25(OH)D levels were significantly decreased in MetS patients, and it was negatively associated with metabolic dysfunctions at baseline and 1-year after. Metabolic aberrations of MetS patients were significantly ameliorated with 1-year follow-up counselling accompanying by notably elevated 25(OH)D levels.

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.

Metabolic syndrome in indigenous communities in Mexico: a descriptive and cross-sectional study

BACKGROUND

An Amerindian genetic background could play an important role in susceptibility to metabolic diseases, which have alarmingly increased in recent decades. Mexico has one of the highest prevalences of metabolic disease worldwide. The purpose of this study was to determine the prevalence of metabolic syndrome and its components in a population with high Amerindian ancestry.

METHODS

We performed a descriptive, quantitative, and analytical cross-sectional study of 2596 adult indigenous volunteers from 60 different ethnic groups. Metabolic syndrome and its components were evaluated using the American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement criteria.

RESULTS

The overall prevalence of metabolic syndrome in the indigenous Mexican population was 50.3%. Although females had a higher prevalence than males (55.6% vs. 38.2%), the males presented with combinations of metabolic syndrome components that confer a higher risk of cardiovascular disease. The most frequent metabolic syndrome component in both genders was low HDL-cholesterol levels (75.8%). Central obesity was the second most frequent component in females (61%), though it had a low prevalence in males (16.5%). The overall prevalence of elevated blood pressure was 42.7% and was higher in males than females (48.8 vs. 40%). We found no gender differences in the overall prevalence of elevated triglycerides (56.7%) or fasting glucose (27.9%).

CONCLUSIONS

We documented that individuals with Amerindian ancestry have a high prevalence of metabolic syndrome. Health policies are needed to control the development of metabolic disorders in a population with high genetic risk.

Circulating miR-130 and its target PPAR-γ may be potential biomarkers in patients of coronary artery disease with type 2 diabetes mellitus

BACKGROUND

Patients of coronary artery disease (CAD) with type 2 diabetes mellitus (DM2) show increased mortality risk than CAD patients without DM2, while few biomarkers can be used to discriminate them.

METHODS

Fifty-nine patients of CAD with DM2 (DM2-CAD group), 79 patients of CAD without DM2 (CAD group), and 63 healthy control subjects were recruited. Circulating miR-130 (miR-130a and miR-130b) and PPAR-γ (peroxisome proliferator-activated receptor gamma) were measured and their Pearson correlation was analyzed. 3' UTR binding prediction and luciferase assay were used to determine the target relationship between miR-130 and PPAR-γ. Receiver operating characteristics (ROC) analysis was performed to test the discrimination ability of miR-130 between DM2-CAD and CAD groups.

RESULTS

miR-130a and miR-130b showed decreased expression in DM2-CAD group when compared with the CAD group and health control. Both bioinformatics and luciferase assays showed that miR-130 could bind the 3' UTR of PPAR-γ. Furthermore, miR-130 negatively correlated with PPAR-γ in both CAD and DM2-CAD group in Pearson's coefficient analysis. Both miR-130a and miR-130b were able to discriminate DM2-CAD group from CAD group and control subjects.

CONCLUSION

Circulating miR-130 may regulate the expression of PPAR-γ and can be used as a biomarker to discriminate DM2-CAD from CAD.

Syndrome 'Z': A Predictor of Angiographic Severity of Coronary Artery Disease in Patients of Acute Coronary Syndrome

BACKGROUND

Owing to the growing evidence that the pathophysiology of obstructive sleep apnoea (OSA) and metabolic syndrome (MS) overlap considerably and both adversely impact cardiovascular health, we hypothesised that the presence of OSA with MS additively and adversely affect the severity of coronary artery disease (CAD). Exploration and understanding of this may have direct implications for the development of targeted, preventive strategies for CAD. Thus, this prospective study was aimed to determine the prevalence of 'Syndrome Z' in patients of MS who present with an acute coronary event and to correlate it with the angiographic severity of CAD in these patients.

METHODS

The present study was a single centre, cross sectional study conducted in a university teaching hospital. In a span of 6 months, 922 patients with acute coronary syndromes (ACS) were screened for the study. Among these, 861 patients had no evidence of MS. The remaining 61 patients who were diagnosed to have MS were then subjected to an overnight sleep study. Only 58 had good sleep data so were included for further analysis. Angiographic parameters in terms of number of vessels involved and culprit lesions were noted and correlated with presence and absence of OSA and also with its severity based on the Apnoea/Hypopnoea Index (AHI).

RESULTS

The prevalence of OSA positivity in patients with MS who presented with ACS was 34.5% (n=20). Most of the patients in the OSA negative group (78.9%, n=30) had disease limited to only one vessel while in the OSA positive group only a minority (15%, n=3) of patients had their disease limited to a single vessel (p=0.001). The number of lesions in the culprit vessel was also significantly less in the OSA negative group compared to the OSA positive group. While in the OSA negative group 68.4% (n=26) patients had a solitary lesion, followed by two and three lesions in 15.8% (n=6) of the patients each, multiple lesions were more common in OSA positive patients, involving 80% of cases (45.0%, n=9 with two lesions; 35.0%, n=7 with three lesions; only 20%, n=4 had a solitary lesion).

CONCLUSIONS

Prevalence of 'Syndrome Z' is high in patients having MS presenting with ACS and it correlates with the angiographic severity of CAD.

Relationships among personality traits, metabolic syndrome, and metabolic syndrome scores: The Kakegawa cohort study

OBJECTIVE

Metabolic syndrome and the presence of metabolic syndrome components are risk factors for cardiovascular disease (CVD). However, the association between personality traits and metabolic syndrome remains controversial, and few studies have been conducted in East Asian populations.

METHODS

We measured personality traits using the Japanese version of the Eysenck Personality Questionnaire (Revised Short Form) and five metabolic syndrome components-elevated waist circumference, elevated triglycerides, reduced high-density lipoprotein cholesterol, elevated blood pressure, and elevated fasting glucose-in 1322 participants aged 51.1±12.7years old from Kakegawa city, Japan. Metabolic syndrome score (MS score) was defined as the number of metabolic syndrome components present, and metabolic syndrome as having the MS score of 3 or higher. We performed multiple logistic regression analyses to examine the relationship between personality traits and metabolic syndrome components and multiple regression analyses to examine the relationship between personality traits and MS scores adjusted for age, sex, education, income, smoking status, alcohol use, and family history of CVD and diabetes mellitus. We also examine the relationship between personality traits and metabolic syndrome presence by multiple logistic regression analyses.

RESULTS

"Extraversion" scores were higher in those with metabolic syndrome components (elevated waist circumference: P=0.001; elevated triglycerides: P=0.01; elevated blood pressure: P=0.004; elevated fasting glucose: P=0.002). "Extraversion" was associated with the MS score (coefficient=0.12, P=0.0003). No personality trait was significantly associated with the presence of metabolic syndrome.

CONCLUSIONS

Higher "extraversion" scores were related to higher MS scores, but no personality trait was significantly associated with the presence of metabolic syndrome.

Alloxan-induced diabetes exacerbates coronary atherosclerosis and calcification in Ossabaw miniature swine with metabolic syndrome

Background

There is a preponderance of evidence implicating diabetes with increased coronary artery disease (CAD) and calcification (CAC) in human patients with metabolic syndrome (MetS), but the effect of diabetes on CAD severity in animal models remains controversial. We investigated whether diabetes exacerbates CAD/CAC and intracellular free calcium ([Ca²⁺]_i) dysregulation in the clinically relevant Ossabaw miniature swine model of MetS.

Methods

Sixteen swine, eight with alloxan-induced diabetes, were fed a hypercaloric, atherogenic diet for 6 months. Alloxan-induced pancreatic beta cell damage was examined by immunohistochemical staining of insulin. The metabolic profile was confirmed by body weight, complete blood panel, intravenous glucose tolerance test (IVGTT), and meal tolerance test. CAD severity was assessed with intravascular ultrasound and histology. [Ca²⁺]_i handling in coronary smooth muscle (CSM) cells was assessed with fura-2 ratiometric imaging.

Results

Fasting and post-prandial blood glucose, total cholesterol, and serum triglycerides were elevated in MetS-diabetic swine. This group also exhibited hypoinsulinemia during IVGTT and less pancreatic beta cell mass when compared to lean and MetS-nondiabetic swine. IVUS analysis revealed that MetS-diabetic swine had greater percent wall coverage, percent plaque burden, and calcium index when compared to lean and MetS-nondiabetic swine. Fura-2 imaging of CSM [Ca²⁺]_i revealed that MetS-nondiabetic swine exhibited increased sarcoplasmic reticulum Ca²⁺ store release and Ca²⁺ influx through voltage-gated Ca²⁺ channels compared to lean swine. MetS-diabetic swine exhibited impaired Ca²⁺ efflux.

Conclusions

Diabetes exacerbates coronary atherosclerosis and calcification in Ossabaw miniature swine with MetS, accompanied by progression of [Ca²⁺]_i dysregulation in advanced CAD/CAC. These results recapitulate increased CAD in humans with diabetes and establish Ossabaw miniature swine as an animal model for future MetS/diabetes comorbidity 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.

Effect of Metabolic Syndrome Score, Metabolic Syndrome, and Its Individual Components on the Prevalence and Severity of Angiographic Coronary Artery Disease

Background:

The clinical significance of metabolic syndrome (MS) score, MS, and its individual components with respect to risk prediction of coronary artery disease (CAD) remains unclear. The objective of this study was to investigate whether and to what extent MS score, MS, and its individual components were related to the risk of CAD.

Methods:

Among 1191 participants who underwent coronary angiography for the confirmation of suspected myocardial ischemia, 858 were included in this study according to the inclusion criteria from September 2010 to June 2013. MS was diagnosed with the 2005 National Cholesterol Education Program Adult Treatment Panel III criteria. The severity of coronary atherosclerosis was assessed by Gensini score.

Results:

The results showed that the age- and sex-adjusted odds ratios (ORs) for CAD were as follows: MS score, 1.327; MS, 2.013; elevated waist circumference, 1.447; reduced high-density lipoprotein cholesterol, 1.654; and elevated fasting glucose, 1.782; all P < 0.05; whereas for elevated triglycerides, 1.324, and elevated blood pressure, 1.342, both P > 0.05. After multivariate adjustment, results showed that only MS and elevated fasting glucose were significantly associated with CAD (OR, 1.628, 95% confidence interval [CI], 1.151–2.305, P = 0.006 for elevated fasting glucose, and OR, 1.631, 95% CI, 1.208–2.203, P = 0.001 for MS). The study showed that only MS score and elevated fasting glucose were significantly associated with Gensini score (standardized coefficient, 0.101, P = 0.031 for elevated fasting glucose and standardized coefficient, 0.103, P = 0.009 for MS score).

Conclusions:

The present study demonstrated that MS score, MS, and its individual components might have different contributions to CAD prevalence and severity. MS and elevated fasting glucose were independent risk factors for the prevalence of angiographic CAD whereas MS score and elevated fasting glucose were significantly associated with the severity of CAD.

Association of metabolic syndrome and electrocardiographic markers of subclinical cardiovascular disease

BACKGROUND

The metabolic syndrome (MetS) and its components are well-established risk factors for cardiovascular diseases (CVD). It is inconclusive whether MetS and MetS score are associated with electrocardiographic markers of subclinical CVD, therefore we investigated this in a population without pre-existing CVD.

METHODS

We performed a cross-sectional analysis in the Netherlands Epidemiology of Obesity study, a population-based cohort including 6671 participants aged 45-65. We excluded participants with pre-existing CVD (n = 499) or missing MetS components (n = 58). MetS was defined based on a modified definition of Adult Treatment Panel III. Subclinical CVD parameters were determined with 12-lead ECGs. MetS score was defined as number of abnormal MetS components and obesity as Body Mass Index (BMI) ≥30 kg/m². We performed weighted adjusted linear regression analyses.

RESULTS

Our study population (n = 6114) had a mean (SD) BMI of 26.3 (4.4) kg/m² and MetS was present in 24% of participants. All ECG parameters differed between participants with and without MetS. Per additional MetS component, heart rate was 0.17 SD (95% CI 0.15, 0.19) higher, P wave duration, QRS complex duration and corrected QT interval were longer [0.07 SD (0.05, 0.10), 0.04 SD (0.01, 0.06) and 0.05 SD (0.02, 0.08) respectively], P wave axis, T wave axis and QRS axis were lower [-0.10 SD (-0.12, -0.07), -0.07 SD (-0.10, -0.05) and -0.19 SD (-0.22, -0.16)] and percentage small Q-waves also increased per additional MetS component. Associations were stronger in non-obese than obese participants. In joint modelling of all MetS components, increased waist circumference showed strongest associations with ECG parameters.

CONCLUSIONS

Metabolic syndrome score and its individual components, in particular abdominal obesity, are associated with ECG markers of subclinical CVD, showing the importance of limiting the amount of MetS components in both obese and non-obese persons.

Subclinical left ventricular systolic dysfunction in patients with metabolic syndrome: A case-control study using two-dimensional speckle tracking echocardiography

BACKGROUND

The dramatic increase in the prevalence of metabolic syndrome is associated with more increased cardiovascular morbidity and mortality in this group. Some recent studies suggested that metabolic syndrome is associated with increased risk of subclinical left ventricular (LV) systolic dysfunction. In the present cross-sectional case-control study, the utility of two-dimensional speckle tracking echocardiography (STE) was examined to detect early LV systolic dysfunction in this population.

METHODS

A total of 75 clinically asymptomatic subjects with left ventricular ejection fraction (LVEF) ≥ 55%, 39 without metabolic syndrome and 36 with metabolic syndrome, matched for gender and age, were enrolled in this case-control study. Metabolic syndrome was diagnosed using the National Cholesterol Education Program/Adult Treatment Panel III criteria. LV systolic function was assessed by STE-derived global and segmental longitudinal strain (εLL).

RESULTS

Global εLL was significantly lower in patients with metabolic syndrome compared with normal population (-18.41 ± 2.20% vs. -21.2 ± 2.1%, P < 0.001). Segmental εLL was significantly lower in patients with metabolic syndrome in comparison to control group except for basal anteroseptal (-19.95 ± 2.90% vs. -21.15 ± 3.30%, P = 0.106), basal anterolateral (-17.5 ± 5.0% vs. -18.3 ± 4.1%, P = 0.437), and basal inferolateral segments (-18.1 ± 6.3% vs. -18.9 ± 4.1%, P = 0.526).

CONCLUSION

STE-derived longitudinal LV strain (εLL), a marker of subclinical cardiovascular disease, is impaired in asymptomatic individuals with metabolic syndrome and normal LVEF.

Classification of metabolic syndrome according to lipid alterations: analysis from the Mexican National Health and Nutrition Survey 2006

Background

There are 16 possible Metabolic Syndrome (MS) combinations out of 5 conditions (glucose intolerance, low levels of high-density lipoprotein Cholesterol (HDL-C), high triglycerides, high blood pressure and abdominal obesity), when selecting those with at least three. Studies suggest that some combinations have different cardiovascular risk. However evaluation of all 16 combinations is complex and difficult to interpret. The purpose of this study is to describe and explore a classification of MS groups according to their lipid alterations.

Methods

This is a cross-sectional study with data from the Mexican National Health and Nutrition Survey 2006. Subjects (n = 5,306) were evaluated for the presence of MS; four mutually-exclusive MS groups were considered: mixed dyslipidemia (altered triglycerides and HDL-C), hypoalphalipoproteinemia: (normal triglycerides but low HDL-C), hypertriglyceridemia (elevated triglycerides and normal HDL-C) and without dyslipidemia (normal triglycerides and HDL-C). A multinomial logistic regression model was fitted in order to identify characteristics that were associated with the groups.

Results

The most frequent MS group was hypoalphalipoproteinemia in females (51.3%) and mixed dyslipidemia in males (43.5%). The most prevalent combination of MS for both genders was low HDL-C + hypertension + abdominal obesity (20.4% females, 19.4% males). The hypoalphalipoproteinemia group was characteristic of women and less developed areas of the country. The group without dyslipidemia was more frequent in the highest socioeconomic level and less prevalent in the south of the country. The mixed dyslipidemia group was characteristic of men, and the Mexico City region.

Conclusions

A simple system to classify MS based on lipid alterations was useful to evaluate prevalences by diverse biologic and sociodemographic characteristics. This system may allow prevention and early detection strategies with emphasis on population-specific components and may serve as a guide for future studies on MS and cardiovascular risk.

Metabolic syndrome: prevalence and association with electrocardiographic abnormalities in Nigerian hypertensive patients

BACKGROUND

Hypertension is an important component of metabolic syndrome, and a third of hypertensive patients have metabolic syndrome, with the common mechanistic pathway believed to be insulin resistance. It is probable that hypertensive patients with metabolic syndrome will have more severe cardiac abnormalities than those without. Similarly, electrocardiogram (ECG) abnormalities have serious implications for cardiovascular disease outcome. Data on association between metabolic syndrome and ECG abnormalities are scarce in Nigeria. This study aimed to assess the prevalence of metabolic syndrome and its components in hypertensive patients and possible association of metabolic syndrome with ECG abnormalities in them.

MATERIALS AND METHODS

One hundred and thirty-five new adult hypertensive patients were studied in a hospital-based cross-sectional study. Metabolic syndrome prevalence was estimated by National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. ECG abnormalities were divided into minor and major abnormalities based on Novacode. SPSS IBM 20 was used to analyze data.

RESULTS

Mean age was 59.19 ± 13.33 (30-75 years). Metabolic syndrome prevalence was 40.74% (28.85% in males; 48.19% in females). Abnormal waist circumference (58.51%) was the commonest additional component of metabolic syndrome in these patients. ECG abnormalities were in 77.78% of the population, with 49.63% and 28.15% being minor and major abnormalities, respectively. There was no significant association between metabolic syndrome and ECG abnormalities in these patients.

CONCLUSION

Prevalence of metabolic syndrome in hypertensive patients was high, central obesity being the commonest component of the syndrome. The high prevalence of ECG abnormalities may be more a reflection of the presence of hypertension than any other component of the syndrome.

A device for performing automated balloon catheter inflation ischemia studies

Coronary collateral growth (arteriogenesis) is a physiological adaptive response to transient and repetitive occlusion of major coronary arteries in which small arterioles (native collaterals) with minimal to no blood flow remodel into larger conduit arteries capable of supplying adequate perfusion to tissue distal to the site of occlusion. The ability to reliably and reproducibly mimic transient, repetitive coronary artery occlusion (ischemia) in animal models is critical to the development of therapies to restore coronary collateral development in type II diabetes and the metabolic syndrome. Current animal models for repetitive coronary artery occlusion implement a pneumatic occluder (balloon) that is secured onto the surface of the heart with the suture, which is inflated manually, via a catheter connected to syringe, to effect occlusion of the left anterior descending coronary artery (LAD). This method, although effective, presents complications in terms of reproducibility and practicality. To address these limitations, we have designed a device for automated, transient inflation of balloon catheters in coronary artery occlusion models. This device allows repeated, consistent inflation (to either specified pressure or volume) and the capability for implementing very complex, month-long protocols. This system has significantly increased the reproducibility of coronary collateral growth studies in our laboratory, resulting in a significant decrease in the numbers of animals needed to complete each study while relieving laboratory personnel from the burden of extra working hours and enabling us to continue studies over periods when we previously could not. In this paper, we present all details necessary for construction and operation of the inflator. In addition, all of the components for this device are commercially available and economical (Table S1). It is our hope that the adoption of automated balloon catheter inflation protocols will improve the experimental reliability of transient ischemia studies at many research institutions.

Correlation of severity of coronary artery disease with insulin resistance

BACKGROUND

Insulin resistance (IR) has known to be associated with coronary artery disease (CAD), but the assessment of severity of the CAD based on IR in type 2 diabetes mellitus has not been established in detail.

AIMS

The aim of our study was to establish the correlation between IR and the severity of CAD in type 2 diabetes mellitus.

MATERIALS AND METHODS

In a cross-sectional study design, 61 consecutive patients with type 2 diabetes mellitus who underwent coronary angiogram for the evaluation of CAD were recruited. Fasting blood glucose, fasting insulin levels, systolic blood pressure and total cholesterol/high density lipoprotein-cholesterol ratio were determined. Homeostasis model assessment-IR (HOMA-IR) was correlated with severity of CAD, which was measured by modified Gensini Score.

RESULTS

There was a significant correlation between log HOMA-IR and severity of CAD (r = 0.303, P = 0.009) in diabetic patients. Correlation of the Gensini Score with other known risk factors was not significant.

CONCLUSIONS

The results of our study indicate that we might able to predict the severity of CAD by measure of IR.

Usefulness of metabolic syndrome score in the prediction of angiographic coronary artery disease severity according to the presence of diabetes mellitus: relation with inflammatory markers and adipokines

Background

It is a matter of debate whether metabolic syndrome (MS) improves cardiovascular risk prediction beyond the risk associated with its individual components. The present study examined the association of MS score with high sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), resistin, adiponectin, and angiographic coronary artery disease (CAD) severity according to the presence of DM. In addition, the predictive value of various clinical and biochemical parameters were analyzed, including the MS score for angiographic CAD.

Methods

The study enrolled 363 consecutive patients (196 men, 62 ± 11 years of age) who underwent coronary angiography for evaluation of chest pain. Blood samples were taken prior to elective coronary angiography. MS was defined by the National Cholesterol Education Program criteria, with MS score defined as the numbers of MS components. CAD was defined as > 50% luminal diameter stenosis of at least one major epicardial coronary artery. CAD severity was assessed using the Gensini score.

Results

Of the 363 patients studied, 174 (48%) had CAD and 178 (49%) were diagnosed with MS. When the patients were divided into 4 subgroups according to MS score (0–1, 2, 3, 4–5), IL-6 levels and the CAD severity as assessed by the Gensini score increased as MS scores increased. In contrast, adiponectin levels decreased significantly as MS scores increased. When subjects were divided into two groups according to the presence of DM, the relationships between MS score and IL-6, adiponectin, and Gensini score were maintained only in patients without DM. Age, smoking, DM, MS score, and adiponectin independently predicted angiographic CAD in the whole population. However, age is the only predictor for angiographic CAD in patients with DM.

Conclusions

In the presence of DM, neither adipokines nor MS score predicted angiographic CAD. However, in non-diabetic patients, IL-6 and adiponectin showed progressive changes according to MS score, and MS score was an independent predictor of CAD in patients without DM.

Metabolically obese status with normal weight is associated with both the prevalence and severity of angiographic coronary artery disease

OBJECTIVE

We evaluated prevalence and severity of angiographic coronary artery disease (CAD) according to groups by metabolically obese (MO) and/or weight status.

MATERIAL/METHODS

Normal weight was defined as body mass index (BMI, kg/m²)<25 and obesity was defined as BMI≥25. The MO was determined using the National Cholesterol Education Program-Adult Treatment Panel III classification with Korean-specific cutoffs for abdominal obesity. Therefore, a total of 856 subjects were categorized as follows: (1) metabolically healthy and normal weight (MHNW); (2) metabolically obese but normal weight (MONW); (3) metabolically healthy but obese (MHO); and (4) metabolically abnormally obese (MAO). The presence of obstructive lesion≥50% of coronary artery was considered as an angiographic CAD and the Gensini scoring system was used for the severity.

RESULTS

MONW or MO showed a higher prevalence of CAD than MHNW or non-MO after adjustment for age and sex, respectively (MONW, odds ratio [OR]=1.69, 95% confidence interval [CI]: 1.13-2.51 and MO, OR=1.44, 95% CI: 1.09-1.91). In subjects without diabetes mellitus (DM), MONW or MO showed a marginally higher prevalence of CAD (MONW, OR=1.58, 95% CI: 0.96-2.61 and MO, OR=1.41, 95% CI: 0.96-2.08). MONW was independently associated with a higher severity of angiographic CAD than MHNW after age, sex, glomerular filtration rate, smoking status, high sensitive C-reactive protein, and use of anti-platelet and anti-angina drugs (β=0.118, P=0.005). And MO was associated with a higher severity of angiographic CAD than non-MO after adjustment for age and sex (β=0.077, P=0.024). The above associations were also consistent in subjects without DM (MONW, β=0.147, P=0.003 and MO, β=0.129, P=0.005).

CONCLUSIONS

MONW or MO is associated with both the prevalence and severity of angiographic CAD after adjustment for age and sex and MONW is independently associated with the severity of angiographic CAD irrespective of DM. Therefore, subjects with MO but normal weight (MONW) should be carefully examined for angiographic CAD.

The metabolic syndrome, oxidative stress, environment, and cardiovascular disease: the great exploration

The metabolic syndrome affects 30% of the US population with increasing prevalence. In this paper, we explore the relationship between the metabolic syndrome and the incidence and severity of cardiovascular disease in general and coronary artery disease (CAD) in particular. Furthermore, we look at the impact of metabolic syndrome on outcomes of coronary revascularization therapies including CABG, PTCA, and coronary collateral development. We also examine the association between the metabolic syndrome and its individual component pathologies and oxidative stress. Related, we explore the interaction between the main external sources of oxidative stress, cigarette smoke and air pollution, and metabolic syndrome and the effect of this interaction on CAD. We discuss the apparent lack of positive effect of antioxidants on cardiovascular outcomes in large clinical trials with emphasis on some of the limitations of these trials. Finally, we present evidence for successful use of antioxidant properties of pharmacological agents, including metformin, statins, angiotensin II type I receptor blockers (ARBs), and angiotensin II converting enzyme (ACE) inhibitors, for prevention and treatment of the cardiovascular complications of the metabolic syndrome.

Why is coronary collateral growth impaired in type II diabetes and the metabolic syndrome?

Type II diabetes and the metabolic syndrome are strong predictors of severity of occlusive coronary disease and poorer outcomes of coronary revascularization therapies. Coronary collateral growth can provide an alternative or accessory pathway of revascularization. However, collateral growth is impaired in type II diabetes and the metabolic syndrome. Although many factors necessary for collateral growth are known and many interventions have shown promising results in animal studies, not a single attempt to induce coronary collateral growth in human clinical trials has led to satisfactory results. Accordingly, the first part of this review outlines the known deleterious effects of diabetes and the metabolic syndrome on factors necessary for collateral growth, including pro-angiogenic growth factors, endothelial function, the redox state of the coronary circulation, intracellular signaling, leukocytes and bone marrow-derived progenitors cells. The second section highlights the gaps in our current knowledge of how these factors interact with the radically altered environment of the coronary circulation in diabetes and the metabolic syndrome. The interplay between these pathologies and inadequately explored areas related to the temporal regulation of collateral remodeling and the roles of the extracellular matrix, vascular cell phenotype and pro-inflammatory cytokines are emphasized with implications to development of efficient therapies.

Electrocardiographic abnormalities associated with the metabolic syndrome and its components: the multi-ethnic study of atherosclerosis

BACKGROUND

The association between metabolic syndrome and electrocardiographic (ECG) abnormalities is not well established.

METHODS

ECG tracings of 6,765 men and women aged 45-84 years, free of clinical cardiovascular disease, from the Multi-Ethnic Study of Atherosclerosis were obtained (2000-2002) and classified as normal or having major or minor abnormalities. We evaluated the associations of metabolic syndrome and its components with ECG abnormalities, adjusting for age, ethnicity, and gender and testing for effect modification by ethnicity and gender.

RESULTS

The associations of metabolic syndrome, hypertension, and high triglycerides with ECG abnormalities varied significantly by gender. In males, metabolic syndrome and hypertension were significantly associated with major ECG abnormality [1.69 (1.33-2.13), and 2.22 (1.72-2.86), respectively] after adjusting for ethnicity and gender. Hypertension was also associated significantly with minor ECG abnormality in males after adjusting for age and ethnicity. In females, metabolic syndrome and hypertension were significantly associated with major [1.84 (1.44-2.37), and 1.68 (1.27-2.22), respectively] and minor [1.38 (1.19-1.59), and 1.53 (1.32-1.79), respectively] ECG abnormalities after adjusting for age and ethnicity. High triglycerides were only significantly associated with major ECG abnormality in females after adjusting for age and ethnicity. After adjusting for age, ethnicity, and gender, central obesity and high fasting blood glucose were significantly associated with major and minor ECG abnormalities, whereas low high-density lipoprotein cholesterol was significantly associated with major ECG abnormality only.

CONCLUSIONS

Metabolic syndrome and its components are associated with major and/or minor ECG abnormalities. The relationship of metabolic syndrome, hypertension, and high triglycerides with ECG abnormalities varied according to gender.

Differential relationship between metabolic syndrome score and severity of coronary atherosclerosis as assessed by angiography in a non-diabetic and diabetic Korean population

Whether the metabolic syndrome (MetS) has prognostic value for coronary artery disease (CAD) beyond its individual components is controversial. We compared the relationship between the number of MetS components and CAD severity as assessed by angiography in non-diabetic and diabetic subjects. We consecutively enrolled 527 patients who underwent their first coronary angiography. Patients were divided into four groups according to the number of MetS components: 0/1, 2, 3, and 4/5. A coronary atherosclerosis score was used to quantify the extent of atherosclerotic involvement. The relationship between the MetS score and angiographic CAD severity or clinical presentation was compared between non-diabetic and diabetic subjects. Individuals with the MetS (n = 327) had a higher prevalence of CAD (60% vs 32%, P < 0.001), multi-vessel disease (34% vs 16%, P < 0.001), and acute coronary syndromes (49% vs 26%, P < 0.001) than those without the MetS. In the non-diabetic group, atherosclerosis score increased with the MetS score (1.0 ± 2.1, 2.0 ± 2.9, 2.8 ± 2.9, and 3.6 ± 3.9, P < 0.001) whereas there was no significant difference in the diabetic group (0.5 ± 1.0, 5.2 ± 4.7, 4.2 ± 2.9, and 4.4 ± 3.5, P = 0.102). The MetS score is related to CAD severity in non-diabetic patients but the association between the MetS score and angiographic CAD severity may be obscured in the presence of diabetes.

[Prevalence of metabolic syndrome and its components in patients with acute coronary syndrome]

INTRODUCTION AND OBJECTIVES

A large proportion of patients with coronary disease have metabolic syndrome, although the frequency and association of its different components are not well understood. The aim of this study was to determine the prevalence of metabolic syndrome and the combination of its components in a Spanish cohort of patients with acute coronary syndrome.

METHODS

Clinical histories of 574 inpatients with acute coronary syndrome in 6 tertiary hospitals were reviewed and the presence of metabolic syndrome and its components determined by applying Adult Treatment Panel III criteria. In a second step, the components of the metabolic syndrome were analyzed, excluding those patients with diabetes mellitus.

RESULTS

The metabolic syndrome was present in 50.9% of patients and was more frequent in women than in men (66.3% vs. 47.3%; P<.001). The most prevalent component was carbohydrate metabolism disorder (85.3%), followed by low high-density lipoprotein cholesterol (HDLc) levels (80.5%). In nondiabetic patients, 34.6% had metabolic syndrome and the most prevalent component was low HDLc levels (86%), followed by high blood pressure and hypertriglyceridemia and, in fourth place, impaired fasting serum glucose levels.

CONCLUSIONS

The metabolic syndrome has a high prevalence in patients with an acute coronary syndrome, especially in women. The most frequent components are hyperglycemia and low HDLc levels. After excluding diabetic patients, the most prevalent diagnostic criterion of metabolic syndrome was low HDLc levels. Full English text available from: www.revespcardiol.org.