Subclinical atherosclerosis determinants in morbid obesity

Serum endocan as a predictive biomarker of cardiovascular risk in obese pediatric patients

BACKGROUND

Endocan is a soluble dermatan sulfate proteoglycan (50 kDa) secreted by endothelial cells and expressed by dermal, coronary, pulmonary and adipose tissue microvasculature. It plays an important role in the pathogenesis of vascular disorders, inflammatory state, endothelium dysfunction and neoangiogenesis. Aims of the study were to compare fasting serum endocan levels between children with obesity and healthy controls and to investigate the relationships between endocan, body mass index (BMI) and other indices of cardiometabolic risk.

METHODS

This single-center, observational, retrospective study included 19 pediatric patients with obesity aged 11.94 ± 0.52 years and 19 lean matched controls. Each patient underwent clinical and auxological examination and laboratory investigations including routine organs function tests and lipid profile. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Fasting endocan serum levels were measured using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

Compared to healthy subjects, serum endocan levels were found to be significantly upraised in children with obesity. Endocan resulted significantly correlated with insulin levels (rho 0.47; p = 0.04); in addition, an association with HOMA-IR values with a trend toward the statistical significance (rho 0.43; p = 0.07) was found. No significant correlation with fasting blood glucose values and lipid serum levels was demonstrated. Although not statistically significant, a correlation between endocan and the presence and grading of liver steatosis on ultrasound (rho 0.51; p = 0.08 and rho 0.51; p = 0.08, respectively) was found.

CONCLUSIONS

These findings confirm the association between endothelial damage and insulin resistance in children with obesity. Endocan could be used as a biomarker of early endothelial dysfunction in children with obesity and could be a valid predictor of future cardiovascular risk in adulthood.

Association between hemoglobin A1c and asymptomatic carotid intima-media thickness in middle-aged and elderly populations without diabetes

BACKGROUND AND AIMS

Carotid atherosclerosis, including carotid artery intima-media thickness, plaques, and stenosis, is an important risk factor for stroke. However, the association between hemoglobin A_1c (HbA_1c) and carotid intima-media thickness (cIMT) was inconsistent. The aim of this study was to explore the association between HbA_1c and the risk of increased cIMT among the Chinese population aged ≥40 years without diabetes.

METHODS AND RESULTS

A total of 3528 participants without diabetes from the China National Stroke Screen Survey program were enrolled in this study. cIMT was measured using duplex ultrasound examination. Logistic regression models were used to assess the association between HbA_1c level and the risk of increased cIMT. A total of 565 (16.0%) participants had increased cIMT. After adjustment for other potential confounding factors, higher levels of HbA_1c increased the risk of increased cIMT compared with the lowest level, and the odds ratios for quartile 2, quartile 3, and quartile 4 were 1.58, 1.67, and 1.98, respectively. Age had an interaction impact on the association between HbA_1c level and the risk of increased cIMT.

CONCLUSION

In this large-scale and cross-sectional study, high-normal HbA_1c was associated with the risk of increased asymptomatic cIMT in a rural Chinese population without diabetes, especially in individuals aged <60 years.

Impact of bariatric surgery on subclinical atherosclerosis in patients with morbid obesity

BACKGROUND

The main cause of death in obese individuals is cardiovascular disease precipitated by atherosclerosis. Endothelial dysfunction and inflammation are considered early events in the development of the disease.

OBJECTIVES

The aim of this study was to identify biomarkers of subclinical atherosclerosis in patients with morbid obesity by comparing clinical, vascular, and biochemical parameters indicative of endothelial dysfunction in patients with and without atheromatous plaque and monitoring changes after bariatric surgery.

SETTINGS

Multicenter collaboration between Biochemistry and Biomedicine Department in Barcelona University and University Hospital Arnau de Vilanova in Lleida.

METHODS

Plasma samples from 66 patients with morbid obesity were obtained before bariatric surgery and at 6 and 12 months after. Patients were divided into 2 groups based on the presence of atheromatous plaque. We used contrast-enhanced carotid ultrasound, enzyme-linked immunosorbent assay, Griess, and EndoPAT-2000 methods.

RESULTS

Patients with plaque showed the worst profile of cardiovascular risk factors. Carotid intima-media thickness and plasminogen activator inhibitor-1 were higher in plaque group (P < .0001). After bariatric surgery, vasa vasorum, oxidized low-density lipoprotein, and plasminogen activator inhibitor-1 decreased (P < .0001 in all cases).

CONCLUSIONS

Obesity promotes atherogenesis, leading to vascular endothelial damage. Bariatric surgery reduces cardiovascular risk and the prognosis is better for patients without plaque. The increase in plasminogen activator inhibitor-1, carotid intima-media thickness, and vasa vasorum proliferation might be the first alterations in the atheromatous process in obesity and could serve as good biomarkers of subclinical atherosclerosis.

Cardiometabolic risk factors and Framingham Risk Score in severely obese patients: Baseline data from DieTBra trial

BACKGROUND AND AIMS

Little is known about differences of cardiometabolic risk factors (CMRF) and the function of Framingham Risk Score (FRS) within severe obesity, thus we aimed to study not only CMRF and FRS, but to determine significant differences between BMI ranges within severe obesity.

METHODS AND RESULTS

In this baseline analysis of the Traditional Brazilian Diet (DieTBra) Trial, several CMRF were assessed in 150 adult patients in two BMI ranges: 35.0-44.9 kg/m² (n = 76) and ≥45 kg/m² (n = 74). Body composition was evaluated by multifrequency bioelectrical impedance analysis to measure the percent of body fat, visceral fat area and waist circumference. Pearson's Chi-squared, Fisher's Exact, Student's t-test, and Mann-Whitney's test were used in the statistical analysis with a 5% significance level. Hypertension, C-reactive protein, systolic and diastolic blood pressure and positive family history for heart diseases were more prevalent in BMI ≥45.0 kg/m² (p < 0.05). Mean values of waist circumference, body fat %, visceral fat area, and systolic blood pressure were significantly higher in patients with BMI ≥45.0 kg/m². Regarding the function of FRS, 40.0% of the patients were at high risk. No differences were found for diabetes, lifestyle, lipid parameters, and FRS within different BMI ranges, except for dyslipidemia, significantly higher among participants with BMI 35.0-44.9 kg/m².

CONCLUSION

BMI >45 kg/m² was associated with higher prevalence of hypertension, systolic and diastolic blood pressure, C-reactive protein, waist circumference, body fat % and family history of heart diseases, enhancing the risk for the occurrence of cardiovascular diseases.

Obesity impairs leukocyte-endothelium cell interactions and oxidative stress in humans

BACKGROUND

To evaluate the relationship between leukocyte-endothelial cell interactions and oxidative stress parameters in non-diabetic patients with different grades of obesity.

MATERIAL AND METHODS

For this cross-sectional study, 225 subjects were recruited from January 1, 2014 to December 31, 2016 and divided into groups according to BMI (<30 kg/m² , 30-40 kg/m² and >40 kg/m²). We determined clinical parameters, systemic inflammatory markers, soluble cellular adhesion molecules, leukocyte-endothelium cell interactions-rolling flux, velocity and adhesion-, oxidative stress parameters-total ROS, total superoxide, glutathione-and mitochondrial membrane potential in leukocytes.

RESULTS

We verified that HOMA-IR and hsCRP increased progressively as obesity developed, whereas A1c, IL6 and TNFα were augmented in the BMI > 40 kg/m² group. The cellular adhesion molecule sP-selectin was increased in patients with obesity, while sICAM, total ROS, total superoxide and mitochondrial membrane potential were selectively higher in the BMI > 40 kg/m² group. Obesity induced a progressive decrease in rolling velocity and an enhancement of rolling flux and leukocyte adhesion.

CONCLUSION

Our findings reveal that endothelial dysfunction markers are altered in human obesity and are associated with proinflammatory cytokines and increased oxidative stress parameters.

Lipid discordance and carotid plaque in obese patients in primary prevention

INTRODUCTION

Obese patients with lipid discordance (non-HDL cholesterol levels 30mg/dL above the LDL-c value) may have a greater prevalence of carotid atherosclerotic plaque (CAP). Our study objectives were: 1) To assess the prevalence of lipid discordance in a primary prevention population of obese patients; 2) To investigate the association between lipid discordance and presence of CAP.

METHODS

Obese subjects aged >18 years (BMI ≥30kg/m²) with no cardiovascular disease, diabetes, or lipid-lowering treatment from six cardiology centers were included. Lipid discordance was defined when, regardless of the LDL-c level, the non-HDL cholesterol value exceeded the LDL-c value by 30mg/dL. Presence of CAP was identified by ultrasonography. Univariate and multivariate analyses were performed to explore the association between lipid discordance and presence of CAP.

RESULTS

The study simple consisted of 325 obese patients (57.2% men; mean age, 52.3 years). Prevalence of lipid discordance was 57.9%. CAP was found in 38.6% of patients, but the proportion was higher in subjects with lipid discordance as compared to those without this lipid pattern (44.4% vs. 30.7%, P=.01). In both the univariate (OR: 1.80; 95% CI: 1.14-2.87; P=.01) and the multivariate analysis (OR: 2.07; 95% CI: 1.22-3.54; P=.007), presence of lipid discordance was associated to an increased probability of CAP.

CONCLUSION

In these obese patients, lipid discordance was associated to greater prevalence of CAP. Evaluation of obese patients with this strategy could help identify subjects with higher residual cardiovascular risk.

Causes of changes in carotid intima-media thickness: a literature review

Atherosclerosis causes significant morbidity and mortality. Carotid intima-media thickness (CIMT) predicts future cardiovascular and ischaemic stroke incidence. CIMT, a measure of atherosclerotic disease, can be reliably determined in vivo by carotid ultrasound. In this review, we determined that CIMT is associated with traditional cardiovascular risk factors such as age, sex, race, smoking, alcohol consumption, habitual endurance exercise, blood pressure, dyslipidemia, dietary patterns, risk-lowering drug therapy, glycemia, hyperuricemia, obesity-related anthropometric parameters, obesity and obesity-related diseases. We also found that CIMT is associated with novel risk factors, including heredity, certain genotypic indices, anthropometric cardiovascular parameters, rheumatoid arthritis, immunological diseases, inflammatory cytokines, lipid peroxidation, anthropometric hemocyte parameters, infectious diseases, vitamin D, matrix metalloproteinases, and other novel factors and diseases. However, the conclusions are inconsonant; the underlying causes of these associations remain to be further explored.

IGF-1 and Insulin Resistance Are Major Determinants of Common Carotid Artery Thickness in Morbidly Obese Young Patients

We assessed the relationship between insulin resistance, serum insulin-like growth factor 1 (IGF-1) levels, and common carotid intima–media thickness (CC-IMT) in morbidly obese young patients. A total of 249 patients (aged 37.9 ± 9.8 years, body mass index [BMI] 45.6 ± 8.3 kg/m2) were evaluated (metabolic tests, serum IGF-1 measurements, homeostasis model assessment—insulin resistance [HOMA-IR], and ultrasonographically assessed CC-IMT) in a research program for bariatric surgery candidates. After adjusting for age, gender, BMI, systolic blood pressure, uric acid, antihypertensive and lipid-lowering treatment, metabolic syndrome, and metabolic class, both HOMA-IR and IGF-1 z-score were significantly associated with CC-IMT. These results were confirmed in logistic regression analysis, in which age (β = 1.11, P = .001), gender (β = 3.19, P = .001), HOMA-IR (β = 1.221, P = .005), and IGF-1 z-score (β = 1.734, P = .009) were the only independent determinants of abnormal CC-IMT, presumably modulating the effect of the other risk factors included in the regression. Area under the receiver–operating characteristic curve for the model was 0.841 (confidence interval: 0.776-0.907; P < .001). In conclusion, in morbidly obese young adults, insulin resistance and IGF-1 z-score are significantly associated with CC-IMT, independent of other major cardiovascular risk factors.

Evidence for contemporary arterial stiffening in obese children and adolescents using pulse wave velocity: A systematic review and meta-analysis

INTRODUCTION

Pulse wave velocity (PWV) and augmentation index (AI) may provide information on future cardiovascular risk. Reports are conflicting on whether obese children show evidence of raised PWV and AI.

METHODS

Systematic review and meta-analysis of published studies using EMBASE, Web-of-Science and PUBMED databases for studies reporting PWV and AI in obese versus non-obese controls(<age 18 years). Studies were pooled in meta-analyses to generate weighted mean differences (WMD) using random effects methodology. Analyses were repeated by method, quality grade and anatomical region.

RESULTS

383 studies were found in initial searches and 81 were assessed in detail; 14 studies (6677 total participants, 1120 obese and 5557 non-obese) were suitable for meta-analysis for PWV, and 5 studies (728 participants obese and 317 non-obese) for AI. Across all studies, obese children had higher PWV than non-obese children (WMD 0.45(95% confidence interval 0.10 to 0.81 ms(-)(1))). This difference was not significant when only studies with low/medium risk of bias were included. Obese subjects had higher PWV measured directly at the carotid (WMD 0.51 (0.35-0.67 ms(-)(1))) and aorta (WMD 1.33 (0.36-2.31)). No significant differences were found for AI. Heterogeneity was high in all analyses(I(2) > 90% in PWV and AI meta-analyses).

CONCLUSION

There is moderate evidence that obese children have increased arterial stiffening, especially in central arteries. This supports concerns about future CVD risk in obese children. Developing effective obesity interventions must remain a health priority.

Role of Cardiovascular Ultrasound in the Evaluation of Obese Subjects

Obesity represents a worldwide increasing health problem. Obesity, through complex and not fully understood pathogenetic mechanisms, induces different structural and functional changes of left heart chambers, right heart chambers, and arteries. Ultrasound techniques are the first choice for a comprehensive assessment of the cardiovascular adaptation to obesity. This review summarizes the up-to-date literature on the topic, with particular focus on the main clinical studies, which range over different cardiovascular adaptations to obesity, namely left ventricular mass, diastolic function, right ventricle structure and function, arterial stiffness, and intima-media thickness. Also, the importance of epicardial fat and of the degree of obesity is described. Finally, the role of weight loss and bariatric surgery and the study of cardiovascular obesity-induced abnormalities in children and adolescent are discussed.