Nontraditional risk factors and biomarkers for cardiovascular disease: mechanistic, research, and clinical considerations for youth: a scientific statement from the American Heart Association

Correlation between the plasma fibrinogen concentration and coronary heart disease severity in Moroccan patients with type 2 diabetes. Prospective study

AIM

The present study aims at determining the relationship between the plasma fibrinogen concentration and the severity of coronary heart disease in type 2 diabetic patients.

METHODS

Prospective analytical survey, based on a sample of 120 subjects divided in four groups: 30 non diabetic coronary patients (G1), 30 coronary diabetic patients (G2), 30 non-coronary diabetic patients (G3), and 30 healthy subjects (G4).

RESULTS

The average age was 59.58±7.88 years; female gender predominated by 52.5%. The plasma fibrinogen concentration corresponded to 3.46g/L±0.86 in G1; 3.73g/L±1.11 in G2; 3.06g/L±0.98 in G3 and 2.46g/L±0.51 in G4; with a significant difference between the four groups (P=0.001). The plasma fibrinogen concentration increased in parallel with the cardiovascular risk (P=0.0001); there was also a significant correlation between the plasma fibrinogen concentration and the clinical and para-clinical coronary disease severity (respectively P=0.005 and P=0.0001). A positive correlation between the plasma fibrinogen concentration and hyperglycemia (P=0.035) was found in G4. But no correlation with the lipids parameters, except for the low density-lipoproteins in G3 (P=0.035).

CONCLUSION

In the Moroccan population, the plasma fibrinogen concentration was positively and significantly correlated with the coronary heart disease severity.

The early origins of obesity and insulin resistance: timing, programming and mechanisms

Maternal obesity is associated with an increased risk of developing gestational diabetes mellitus and it also results in an increased risk of giving birth to a large baby with increased fat mass. Furthermore, it is also contributes to an increased risk of obesity and insulin resistance in the offspring in childhood, adolescence and adult life. It has been proposed that exposure to maternal obesity may therefore result in an 'intergenerational cycle' of obesity and insulin resistance. There is significant interest in whether exposure to maternal obesity around the time of conception alone contributes directly to poor metabolic outcomes in the offspring and whether dieting in the obese mother before pregnancy or around the time of conception has metabolic benefits for the offspring. This review focusses on experimental and clinical studies that have investigated the specific impact of exposure to maternal obesity during the periconceptional period alone or extending beyond conception on adipogenesis, lipogenesis and on insulin signalling pathways in the fat, liver and muscle of the offspring. Findings from these studies highlight the need for a better evidence base for the development of dietary interventions in obese women before pregnancy and around the time of conception to maximize the metabolic benefits and minimize the metabolic costs for the next generation.

Screen-Based Behaviors of Children and Cardiovascular Risk Factors

OBJECTIVE

To determine whether the amount of time spent in screen-based behaviors (SBBs; television viewing, computer use, and playing electronic games) is independently associated with individual and clustered cardiovascular disease (CVD) risk factors among elementary school children.

STUDY DESIGN

Baseline data were used from 264 children (age 7-10 years) participating in the Transform-Us! cluster-randomized controlled trial. Time (h/d) spent in SBBs was obtained using a parent proxy-report questionnaire. Anthropometrics, blood pressure (BP), and lipids were measured using standard techniques. A clustered CVD risk score was calculated as the average of the standardized values of the subcomponents (waist circumference [WC], systolic BP, diastolic BP, and lipids).

RESULTS

After adjusting for sex, parent education, physical activity (accelerometry), diet, and WC (when adiposity was not the outcome), television viewing time was positively associated with body mass index z-score (P = .002), WC (P = .02), and systolic BP (P = .05). Electronic games was positively associated with low density lipoprotein levels (P = .05), and total screen-time was positively associated with body mass index (P = .02).

CONCLUSIONS

Differential associations were observed between types of SBBs and CVD risk factors, indicating that not all SBBs are adversely associated with obesity and CVD risk. There is a need to differentiate between types of SBBs when evaluating the CVD risk associated with screen behaviors in children.

TRIAL REGISTRATION

International Standard Randomized Controlled Trial: ISRCTN83725066; Australian New Zealand Clinical Trials Registry: ACTRN12609000715279.

Association between resting heart rate and cardiovascular risk factors in adolescents

This cross-sectional study was performed in 2011 and included 4619 Brazilian adolescents (14-19 years old) to analyze the association between elevated resting heart rate (RHR) and cardiovascular risk factors in boys and girls. RHR and blood pressure were measured using an oscillometric monitor. Overweight was assessed by body mass index and abdominal obesity by waist circumference. Physical activity levels and sedentary behaviors were obtained using a questionnaire. The effect of clustering of cardiovascular risk factors on RHR was analyzed. For boys, abdominal obesity (b = 0.106, p = 0.003), high sedentary behavior (b = 0.099, b < 0.001), physical inactivity (b = 0.049, p = 0.034), and high blood pressure (b = 0.160, p < 0.001) were associated with RHR, whereas for girls, only high blood pressure was associated with RHR (b = 0.259, p < 0.001), after adjustment for age, period of the day, and other cardiovascular risk factors. Boys with five risk factors presented significantly higher (p < 0.05) RHR values (82.5 ± 13.4 beats min(-1)) than those for boys without any cardiovascular risk factors (68.8 ± 10.4 beats min(-1)). The girls with five risk factors presented a mean RHR value of 89.8 ± 9.9 beats min(-1) that was higher (p < 0.05) than that for girls who had no risk factors (79.6 ± 10.9 beats min(-1)).

CONCLUSIONS

Our study demonstrated that while RHR was associated with cardiovascular risk factors in both sexes, the clustering of risk factors amplified the elevation of RHR in a gender-dependent fashion.

WHAT IS KNOWN

• Resting heart rate is a marker of cardiovascular disease and mortality in adults and associated with risk factor such as higher levels of blood pressure, triglycerides, glucose, and obesity in children and adolescents.

WHAT IS NEW

• The data from the current study suggest that the risk factor clustering is associated with elevated resting heart rate in adolescents and that the clustering of risk factors amplifies the elevation of resting heart rate in a gender-dependent fashion.

Chlamydia pneumoniae Clinical Isolate from Gingival Crevicular Fluid: A Potential Atherogenic Strain

Chlamydia pneumoniae has been associated to atherosclerotic cardiovascular diseases. The aim of our study was to characterize, for the first time, a C. pneumoniae strain isolated from the gingival crevicular fluid of a patient with chronic periodontitis, described as a risk factor for cardiovascular diseases. C. pneumoniae isolate was characterized and compared to the respiratory AR-39 strain by VD4-ompA genotyping and by investigating the intracellular growth in epithelial and macrophage cell lines and its ability to induce macrophage-derived foam cells. Inflammatory cytokine levels were determined in the gingival crevicular fluid sample. C. pneumoniae isolate showed a 99% similarity with the AR-39 strain in the VD4-ompA gene sequence and shared a comparable growth kinetic in epithelial cells and macrophages, as evidenced by the infectious progeny and by the number of chlamydial genomic copies. C. pneumoniae isolate significantly increased the number of foam cells as compared to uninfected and LDL-treated macrophages (45 vs. 6%, P = 0.0065) and to the AR-39 strain (45 vs. 30%, P = 0.0065). Significantly increased levels of interleukin 1-β (2.1 ± 0.3 pg/μL) and interleukin 6 (0.6 ± 0.08 pg/μL) were found. Our results suggest that C. pneumoniae may harbor inside oral cavity and potentially be atherogenic, even though further studies will be needed to clarify the involvement of C. pneumoniae in chronic periodontitis as a risk factor for cardiovascular diseases.

Cardiovascular Risk Factors in Subclinical Hypothyroidism: A Case Control Study in Nepalese Population

Objectives. To assess cardiovascular risk factors in Nepalese population with subclinical hypothyroidism as compared to age and sex matched controls. Materials and Methods. A case control study was conducted among 200 subjects (100 subclinical hypothyroid and 100 euthyroid) at B.P. Koirala Institute of Health Sciences, Dharan, Nepal. Demographic and anthropometric variables including systolic and diastolic blood pressure (BP) were taken. Blood samples were assayed for serum free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), and high sensitivity C reactive protein (hs-CRP). Results. Subclinical hypothyroid patients had significantly higher diastolic BP, total cholesterol, LDL cholesterol, and hs-CRP than controls. The odds ratio of having hypercholesterolemia (>200 mg/dL), low HDL cholesterol (<40 mg/dL), undesirable LDL-cholesterol (>100 mg/dL), high hs-CRP (>1 mg/L), and high diastolic BP (>80 mmHg) and being overweight (BMI ≥ 23 Kg/m²) in subclinical hypothyroidism was 2.29 (95% CI; 1.2–4.38, p = 0.011), 1.73 (95% CI; 0.82–3.62, p = 0.141), 3.04 (95% CI; 1.66–5.56, p < 0.001), 2.02 (95% CI; 1.12–3.64, p = 0.018), 3.35 (95% CI; 1.72–6.55, p < 0.001), and 0.9 (95% CI; 0.48–1.67, p = 0.753), respectively, as compared to controls. Conclusion. Subclinical hypothyroid patients are associated with higher risk for cardiovascular disease than euthyroid subjects.

Para- and perirenal ultrasonographic fat thickness is associated with 24-hours mean diastolic blood pressure levels in overweight and obese subjects

Background

Renal sinus fat (RSF) has been recognized as a risk factor for arterial hypertension. This study was addressed to examine whether also para- and perirenal fat accumulation is associated to higher 24-h mean systolic (SBP) and/or diastolic blood pressure (DBP) levels in overweight and obese subjects.

Methods

A cohort of 42 overweight and obese patients, 29 women and 13 men, aged 25–55 years, not treated with any kind of drug, was examined. Body mass index (BMI), waist circumference (WC), fasting insulin and glucose serum levels, insulin resistance (assessed by using the homeostasis model assessment [HOMAIR]), and 24-h aldosterone urine levels were measured. Ambulatory blood pressure monitoring (ABPM) was measured with 15 min intervals from 7.0 a.m. to 11.0 a.m. and with 30 min intervals from 23.0 to 7.0 for consecutive 24 h, starting from 8:30 AM. Measurement of para- and perirenal fat thickness was performed by ultrasounds by a duplex Doppler apparatus.

Results

Para- and perirenal ultrasonographic fat thickness (PUFT) was significantly and positively correlated with WC (p < 0.01), insulin (p < 0.01), HOMAIR (p < 0.01), and 24-h mean DBP levels (p < 0.05). 24-h mean DBP was also significantly and positively correlated with 24-h aldosterone urine concentrations (p < 0.001). A multivariate analysis by multiple linear regression was performed; the final model showed that the association of 24-h mean DBP as dependent variable with PUFT (multiple R = 0.34; p = 0.026) and daily aldosterone production (multiple R = 0.59; p = 0.001) was independent of other anthropometric, hormone and metabolic parameters.

Discussion and Conclusions

This study shows a positive independent association between PUFT and mean 24-h diastolic blood pressure levels in overweight and obese subjects, suggesting a possible direct role of PUFT in increasing daily diastolic blood pressure.

Fibrinolytic effects of peroneal nerve stimulation in patients with lower limb vascular disease

Patients with lower limb vascular disease are at an increased risk of thrombotic events. Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor 1 (PAI-1) are important components of the fibrinolytic system, responsible for clot lysis. This study aimed to establish whether peroneal nerve stimulation (PNS) could promote fibrinolysis within a cohort of vascular patients. Ethical approval was obtained for this prospective case-controlled study. Patients were randomly assigned to active stimulation or control groups. Arterial flow measurements and venous blood samples were taken bilaterally at baseline and following 45 min of PNS. ELISA analysis for plasma t-PA and PAI-1 was performed utilizing commercially available kits. Statistical analysis evaluated the changes in t-PA and PAI-1 levels from baseline for the active (device active), passive (contralateral limb) and control limbs (inactive device applied).Seventy-seven participants were recruited: 30 claudicants (25 active and five controls), 25 patients postoperative infra-inguinal bypass grafts (19 active and six controls) and 22 patients with varicose veins (17 active and five controls). t-PA levels reduced significantly in all groups; however, intergroup analysis demonstrated no statistically significant difference when comparing the active, passive and control limbs (P = 0.079). PAI-1 levels decreased by 16.2% (34.0 ng/ml, SD 52.2) in the active limbs but only 3.6% (11.4 ng/ml, SD 47.4) and 2.6% (2.7 ng/ml, SD 21.3) in the passive and control limbs, respectively (intergroup analysis P < 0.001). No relationship between changes in flow and plasma of t-PA and PAI-1 were demonstrated. Peroneal nerve stimulation may augment fibrinolysis by decreasing plasma levels of PAI-1 levels in patients with lower limb arterial and venous disease.

The Effects of a Low-Carbohydrate Diet vs. a Low-Fat Diet on Novel Cardiovascular Risk Factors: A Randomized Controlled Trial

Increasing evidence supports a low-carbohydrate diet for weight loss and improvement in traditional cardiovascular disease (CVD) markers. Effects on novel CVD markers remain unclear. We examined the effects of a low-carbohydrate diet (<40 g/day; n = 75) versus a low-fat diet (<30% kcal/day from total fat, <7% saturated fat; n = 73) on biomarkers representing inflammation, adipocyte dysfunction, and endothelial dysfunction in a 12 month clinical trial among 148 obese adults free of diabetes and CVD. Participants met with a study dietitian on a periodic basis and each diet group received the same behavioral curriculum which included dietary instruction and supportive counseling. Eighty percent of participants completed the intervention. At 12 months, participants on the low-carbohydrate diet had significantly greater increases in adiponectin (mean difference in change, 1336 ng/mL (95% CI, 342 to 2330 ng/mL); p = 0.009) and greater decreases in intercellular adhesion molecule-1 concentrations (-16.8 ng/mL (-32.0 to -1.6 ng/mL); p = 0.031) than those on the low-fat diet. Changes in other novel CVD markers were not significantly different between groups. In conclusion, despite the differences in weight changes on diets, a low-carbohydrate diet resulted in similar or greater improvement in inflammation, adipocyte dysfunction, and endothelial dysfunction than a standard low-fat diet among obese persons.

Changes in inflammation, oxidative stress and adipokines following bariatric surgery among adolescents with severe obesity

BACKGROUND/OBJECTIVES

Inflammation, oxidative stress and dysregulation of adipokines are thought to be pathophysiological mechanisms linking obesity to the development of insulin resistance and atherosclerosis. In adults, bariatric surgery reduces inflammation and oxidative stress, and beneficially changes the levels of several adipokines, but little is known about the postsurgical changes among adolescents.

SUBJECTS/METHODS

In two separate longitudinal cohorts we evaluated change from baseline of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), monocyte chemo-attractant protein-1 (MCP-1), oxidized low-density lipoprotein cholesterol (oxLDL), adiponectin, leptin and resistin up to 12 months following elective laparoscopic Roux-en-Y gastric bypass (RYGB) or vertical sleeve gastrectomy (VSG) surgery in adolescents with severe obesity.

RESULTS

In cohort 1, which consisted of 39 adolescents (mean age 16.5±1.6 years; 29 females) undergoing either RYGB or VSG, IL-6 (baseline: 2.3±3.4 pg ml(-1) vs 12 months: 0.8±0.6 pg ml(-1), P<0.01), leptin (baseline: 178±224 ng ml(-1) vs 12 months: 41.4±31.9 ng ml(-1), P<0.001) and oxLDL (baseline: 41.6±11.6 U l(-1) vs 12 months: 35.5±11.1 U l(-1), P=0.001) significantly decreased and adiponectin significantly increased (baseline: 5.4±2.4 μg ml(-1) vs 12 months: 13.5±8.9 μg ml(-1), P<0.001). In cohort 2, which consisted of 13 adolescents (mean age 16.5±1.6 years; 10 females) undergoing RYGB, results were similar: IL-6 (baseline: 1.7±0.9 pg ml(-1) vs 12 months: 0.4±0.9 pg ml(-1), P<0.05) and leptin (baseline: 92.9±31.3 ng ml(-1) vs 12 months: 37.3±33.4 ng ml(-1), P<0.001) significantly decreased and adiponectin significantly increased (baseline: 6.1±2.9 μg ml(-1) vs 12 months: 15.4±8.0 μg ml(-1), P<0.001). When the cohorts were combined to evaluate changes at 12 months, oxLDL also significantly decreased (baseline: 39.8±16.7 U l(-1) vs 12 months: 32.7±11.9 U l(-1), P=0.03).

CONCLUSIONS

Bariatric surgery produced robust improvements in markers of inflammation, oxidative stress and several adipokines among adolescents with severe obesity, suggesting potential reductions in risk for type 2 diabetes and cardiovascular disease.

Circulating endothelial cells in children: role of fitness, activity, and adiposity

PURPOSE

Circulating endothelial cells (CEC) are thought to be useful biomarkers of endothelial dysfunction and overall cardiovascular health. The extent to which CEC are influenced by fitness, physical activity, and adiposity in youth remains unknown, as they have seldom been examined in the pediatric population. This study assessed resting levels of CEC in boys and girls of different chronological and biological age and explored the relationship between these cells and aerobic fitness, physical activity, and adiposity.

METHODS

Seventy-five children (39 males; median [interquartile range], age = 14.4 [5.8]) completed two study visits. During the first visit, basic anthropometric data were collected and biological age was calculated. Peak mechanical power (Wpeak) was determined using the McMaster All-Out Continuous cycling test. Participants then wore an accelerometer over a 7-d period to assess habitual levels of moderate-to-vigorous physical activity. During visit 2, percent body fat (%BF) was assessed by dual-energy x-ray absorptiometry. A fasted blood sample was also collected from which concentrations of CEC, identified as CD31CD34CD45CD133, were quantified by flow cytometry.

RESULTS

No differences were seen in CEC by sex, chronological age, or biological age. The median (interquartile range) CEC concentration was 32.3 × 10 (63.0 × 10), representing 1.3% (2.7%) of collected peripheral blood mononuclear cells. CEC concentration was associated with Wpeak normalized to lean body mass (r = 0.36, P < 0.01) and time spent in moderate-to-vigorous physical activity (r = -0.27, P = 0.02). No relationship was observed between CEC and %BF.

CONCLUSION

Healthy children demonstrate relatively low concentrations of CECs. Because CEC represent a population of mature endothelial cells shed from the intima after irreversible damage, they may be more reflective of recent physical activity levels rather than fitness or level of adiposity.

Adiposity and cancer risk: new mechanistic insights from epidemiology

Excess body adiposity, commonly expressed as body mass index (BMI), is a risk factor for many common adult cancers. Over the past decade, epidemiological data have shown that adiposity-cancer risk associations are specific for gender, site, geographical population, histological subtype and molecular phenotype. The biological mechanisms underpinning these associations are incompletely understood but need to take account of the specificities observed in epidemiology to better inform future prevention strategies.

[The role of uric acid in the insulin resistance in children and adolescents with obesity]

Objective:

To investigate the association between serum uric acid levels and insulin resistance in children and adolescents with obesity.

Methods:

Cross-sectional study with 245 children and adolescents (134 obese and 111 controls), aged 8-18 years. The anthropometric variables (weight, height and waist circumference), blood pressure and biochemical parameters were collected. The clinical characteristics of the groups were analyzed by t-test or chi-square test. To evaluate the association between uric acid levels and insulin resistance the Pearson's test and logistic regression were applied.

Results:

The prevalence of insulin resistance was 26.9%. The anthropometric variables, systolic and diastolic blood pressure and biochemical variables were significantly higher in the obese group (p<0.001), except for the high-density-lipoprotein cholesterol. There was a positive and significant correlation between anthropometric variables and uric acid with HOMA-IR in the obese and in the control groups, which was higher in the obese group and in the total sample. The logistic regression model that included age, gender and obesity, showed an odds ratio of uric acid as a variable associated with insulin resistance of 1.91 (95%CI 1.40-2.62; p<−0.001).

Conclusions:

The increase in serum uric acid showed a positive statistical correlation with insulin resistance and it is associated with and increased risk of insulin resistance in obese children and adolescents.

Dietary patterns and lifestyle of patients with myocardial infarction

Civilization diseases, including cardiovascular, are major health problems in current modern society. Numerous studies provided sufficient evidence that variety of risk factors are involved in cardiovascular diseases formation. Of the most important is the lifestyle that largely contributes to our health, up to 50 - 60%. Lifestyle includes all modifiable risk factors that together affect the development of these diseases. In our study we searched and evaluated the nutritional parameters and lifestyle of patients hospitalized in Cardiocentre Nitra. In order to obtain the necessary information we chose the questionnaire method. In our survey 194 patients were included, of which 155 were men (79.89%) and 39 (20.11%) women. These patients were hospitalized with acute myocardial infarction diagnosis. The vast majority of patients had overweight and obesity caused by improper eating habits. The high prevalence of overweight, BMI in the range 25 - 30 kg/m2, was also confirmed as statistically significant, p <0.05 (P=0.02). BMI over 25 kg/m2 was present in 85% of men and 80% of women. The consumption of selected food commodities with evidence of a positive or negative impact on the emergence of acute myocardial infarction was not statistically significant (p >0.05) when evaluating dietary habits. But we can confirm too frequent consumption of chicken at the expense of other types of meat and relatively frequent consumption of fish (once a week). We recorded the preference of semi-skimmed dairy products, but also high and inappropriate consumption of full-fat dairy products in men and women (37% and 17.8%, respectively). Daily intake of fruits and vegetables was in 85.9% of women and 64.7% of men. Everyday intake of bread and pastries was confirmed by 100% of respondents. Lifestyle was evaluated according to the presence of smoking, excessive alcohol consumption, and physical activity. Up to 60.5% of men and 26.4% of women admitted smoking, while 34.6% of men and 7.5% women ended up with the habit after myocardial infarction. The excessive alcohol consumption was not detected in the study group. Approximately 67% of men and 56% of women carry out an easier walking and moderate physical activity while taking into account their health status.

Body fat distribution, metabolic and inflammatory markers and retinal microvasculature in school-age children. The Generation R Study

OBJECTIVE

To examine the associations of body fatness, metabolic and inflammatory markers with retinal vessel calibers among children.

DESIGN

We performed a population-based cohort study among 4145 school-age children. At the median age of 6.0 years (95% range 5.8, 8.0 years), we measured body mass index, total and abdominal fat mass, metabolic and inflammatory markers (blood levels of lipids, insulin and C-peptide and C-reactive protein) and retinal vascular calibers from retinal photographs.

RESULTS

We observed that compared with normal weight children, obese children had narrower retinal arteriolar caliber (difference -0.21 s.d. score (SDS; 95% confidence interval (CI) -0.35, -0.06)), but not venular caliber. Continuous analyses showed that higher body mass index and total body fat mass, but not android/gynoid fat mass ratio and pre-peritoneal fat mass, were associated with narrower retinal arteriolar caliber (P<0.05 for body mass index and total body fat mass), but not with retinal venular caliber. Lipid and insulin levels were not associated with retinal vessel calibers. Higher C-reactive protein was associated with only wider retinal venular caliber (difference 0.10 SDS (95% CI 0.06, 0.14) per SDS increase in C-reactive protein). This latter association was not influenced by body mass index.

CONCLUSIONS

Higher body fatness is associated with narrower retinal arteriolar caliber, whereas increased C-reactive protein levels are associated with wider retinal venular caliber. Increased fat mass and inflammation correlate with microvascular development from school-age onwards.

The relationship between blood pressure, anthropometric indices and metabolic profile in adolescents: a cross sectional study

OBJECTIVE

To investigate the relationship between blood pressure, anthropometric indices and metabolic profile in adolescents.

METHODS

The present cross sectional study was conducted in 1005, 12-y-old junior students referred to 15 urban health centers of Rasht. Samples were recruited randomly and data were collected in a form which consisted of demographic characteristics, history of disease in samples and their immediate families, birth weight, physical examination and clinical examination including height, weight, blood pressure and body mass index. Also, metabolic profiles including fasting blood sugar (FBS), blood sugar (BS), cholesterol, and triglyceride (TG), low density lipoprotein (LDL), high-density lipoprotein (HDL) and insulin levels were measured. Data were analyzed in SPSS software, by descriptive and analytic statistics and p value 0.05 was considered statistically significant.

RESULTS

Eight hundred fifty nine adolescents consisting of 550 (64 %) boys and 309 (34 %) girls participated in this study; 11.4 % (84/739 cases) of the participants had hypertension. The strongest correlation was seen between systolic blood pressure and weight, waist or hip circumferences and insulin levels. Also, FBS had very weak correlation with blood pressure.

CONCLUSIONS

Thus, weight, waist and hip circumferences, insulin levels, high TG and low HDL have been indicated as the strongest correlating factors for high blood pressure.Thus, these factors should be investigated in high risk children and followed in hypertensive child to monitor cardiometabolic risk factors.

Insulin sensitivity and arterial stiffness in youth with type 1 diabetes: the SEARCH CVD study

AIMS

Decreased insulin sensitivity is a cardiovascular risk factor (CVRF) in youth with type 1 diabetes (T1D). Whether baseline insulin sensitivity is independently associated with changes in early arterial stiffness (pulse wave velocity (PWV)) over time in youth with T1D is not known.

METHODS

Two hundred ninety-eight youth with T1D in the SEARCH CVD study had PWV measured~five years apart. Insulin sensitivity and other CVRFs were measured at baseline. The association between baseline insulin sensitivity with PWV over time was explored using linear mixed models. Models were adjusted for baseline age, sex and race, with subsequent adjustment for CVRFs.

RESULTS

There was a significant interaction (p=0.0326) between baseline insulin sensitivity and time on PWV, independent of CVRFs, indicating that higher insulin sensitivity levels were associated with lower rate of change in PWV over time. Other significant predictors of PWV change were baseline age [β=0.007 (p=0.03) increase in logPWV/year increase in age] and mean arterial blood pressure (MAP) [β=0.005 (p<0.01) increase in logPWV/mmHg increase in MAP] and smoking status (current vs. never smoker).

CONCLUSIONS

Lower insulin sensitivity at baseline appears to be an important risk factor for increased arterial stiffness over time in youth with T1D. This identifies a potentially modifiable therapeutic target.

Predictors of metabolic risk in childhood obesity

Most of the complications of juvenile obesity are due to metabolic disturbances induced by an excessive accumulation of fat which leads to chronic diseases like type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Finding effective ways of identifying obese paediatric patients who are at increased risk of developing cardiovascular and metabolic complications has been recognised to be a promising strategy to improve prevention of complications of early obesity. Moreover, correctly identifying obese children who are already affected by metabolic co-morbidities should be a clinical priority. According to the state of the art summarised in this review, traditional metabolic variables included in the definitions of metabolic syndrome (MS), pre-diabetes, non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steato-hepatitis and, in obese girls, the presence of polycystic ovary syndrome are the best available longitudinal predictors of CVD and T2DM among obese children and adolescents. In clinical practice, traditional metabolic variables included in the definitions of MS should be assessed in all obese children and adolescents; fasting metabolic variables have been proposed to identify obese patients likely to be affected by impaired glucose tolerance or T2DM, and ultrasound has proved to be a valid surrogate for biopsy in the diagnosis of NAFLD. Further large longitudinal and cross-sectional studies are needed to improve our chances of identifying obese youth at the highest metabolic risk.

Associations of total and abdominal adiposity with risk marker patterns in children at high-risk for cardiovascular disease

Background

While body mass index percentiles (BMI%) are commonly used to assess childhood cardiovascular risk, waist circumference percentiles (WC%) are not commonly used nor universally accepted. We tested whether BMI% or WC% should be used to identify risk factor patterns in children at high-risk for developing cardiovascular disease (CVD). A total of 107 children (8–19 years) with cardiovascular risk factors or a family history of CVD were studied. Tobacco exposure, screen-time, blood pressure and anthropometric measures were made, as well as serum risk markers. Principal component analysis (PCA) was used to identify patterns explaining risk factor variance. Multiple linear regression was used to test for associations between risk factor patterns, BMI% and WC%.

Results

An adverse lipid pattern (low HDL, high triglycerides and LDL), a pro-inflammatory pattern (high ICAM and TNFαR2), a high blood pressure pattern (high SBP and DBP) and a high Lp(a) pattern were identified. Higher BMI% and WC% were associated with significantly higher levels of the lipid pattern (p < 0.05). BMI% explained 20% of variance in this pattern, whereas WC% explained 22%. When both BMI% and WC% were used together, neither BMI% nor WC% were significantly associated with the lipid pattern. However, BMI% was significantly associated with lower levels of the pro-inflammatory pattern, and WC% was associated higher levels of the pro-inflammatory pattern - together explaining 12% of variance.

Conclusion

In children at high-risk for CVD, BMI% or WC% explained similar variance in an adverse lipid pattern; however, the combination of BMI% and WC% explained greater variance in a pro-inflammatory pattern than either alone. Both WC% and BMI% should both be used in anthropometric assessments of high-risk children.

Blood cell transcriptomic-based early biomarkers of adverse programming effects of gestational calorie restriction and their reversibility by leptin supplementation

The challenge of preventing major chronic diseases requires reliable, early biomarkers. Gestational mild undernutrition in rats is enough to program the offspring to develop later pathologies; the intake of leptin, a breastmilk component, during lactation may reverse these programming effects. We used these models to identify, in peripheral blood mononuclear cells (PBMCs), transcriptomic-based early biomarkers of programmed susceptibility to later disorders, and explored their response to neonatal leptin intake. Microarray analysis was performed in PBMCs from the offspring of control and 20% gestational calorie-restricted dams (CR), and CR-rats supplemented with physiological doses of leptin throughout lactation. Notably, leptin supplementation normalised 218 of the 224 mRNA-levels identified in PBMCs associated to undernutrition during pregnancy. These markers may be useful for early identification and subsequent monitoring of individuals who are at risk of later diseases and would specifically benefit from the intake of appropriate amounts of leptin during lactation.

Heart rate variability and cardiovascular risk factors in adolescent boys

OBJECTIVE

To establish reference values of heart rate variability (HRV) measures in a cohort of adolescent boys and to determine the relationship between HRV and the clustering of risk factors (RFs) for cardiovascular disease.

STUDY DESIGN

This cross-sectional study included 1152 adolescent boys (age: 16.6 ± 1.2 years old). Demographic data, health-related habits, obesity indicators, and blood pressure were evaluated. HRV measures of time (SD of all RR intervals, root mean square of the squared differences between adjacent normal RR intervals, and the percentage of adjacent intervals over 50 ms) and frequency domains were assessed (low [LF] and high [HF] frequency).

RESULTS

The components of HRV were RR interval (827 ± 128 ms), SD of all RR intervals (61.9 ± 23.5 ms), root mean square of the squared differences between adjacent normal RR intervals (54.5 ± 29.4 ms), percentage of adjacent intervals over 50 ms (29.4 ± 20.4%), LF (53 ± 16 nu), HF (47 ± 16), and LF/HF (1.44 ± 1.08). Greater sympathetic and lower parasympathetic modulation at rest were associated with higher adiposity, higher blood pressure and physical inactivity. Adolescents with 2 or more RFs also presented lower HRV than subjects with no RFs (P < .001).

CONCLUSIONS

The study has provided descriptive indicators that help the interpretation of HRV results in adolescents. Lower HRV measures are associated with the clustering of cardiovascular RFs.

Recently discovered adipokines and cardio-metabolic comorbidities in childhood obesity

White adipose tissue (WAT) asset, in terms of cell number, fat storage capacity and endocrine function, is largely determined in early stages of life and is pivotal for shaping the WAT pro-inflammatory behavior. WAT derived adipokines have been shown to play a main role in several cardio-metabolic abnormalities of obesity. This review focuses on the most recently identified adipokines, namely adipocyte-fatty acid-binding protein, chemerin, fibroblast growth factor-21, lipocalin-2, omentin-1 and vaspin; their role in the pathogenesis of obesity and associated cardio-metabolic abnormalities; and on their adaptive response to body weight change. Evidence consistently suggests a pathogenic role for A-FABP, chemerin and FGF-21. Nevertheless, large population studies are needed to verify whether they can be useful to predict the risk of cardio-metabolic abnormalities in adulthood and/or monitor the clinical response to therapeutic interventions.

Sleep duration during the school week is associated with C-reactive protein risk groups in healthy adolescents

BACKGROUND

The prevalence of short sleep duration in adolescence and the relevance of early risk factors to cardiovascular disease in adulthood suggest that adolescence is an opportune time to evaluate links between sleep duration and cardiovascular disease risk. We examined associations among actigraphy-assessed sleep duration and sleep debt with elevated C-reactive protein (CRP), a known risk factor for cardiovascular disease.

METHODS

Participants were 244 (56% Black, 48% male) healthy high school students, each of whom wore wrist actigraphs for one week and provided a fasting blood draw. CRP was examined as both a continuous and categorical outcome, with CRP >3 mg/L identifying a High Risk Group.

RESULTS

Sleep duration and sleep debt were significantly associated with CRP High Risk Group in covariate-adjusted analyses. Shorter sleep duration on school nights was associated with a greater likelihood of being in the High Risk CRP Group. Likelihood of being in the High Risk CRP Group was doubled in students who obtained an average of two or more hours of "catch up" sleep on weekend nights.

CONCLUSIONS

Reduced weekday sleep duration and sleep debt were both associated with CRP Risk Group in adolescence. That these relationships may be observed prior to the onset of clinical disease suggests that adolescence may provide an opportune period for disease prevention.

Is air quality index associated with cardiometabolic risk factors in adolescents? The CASPIAN-III Study

OBJECTIVE

This study aims to evaluate the association of air quality index (AQI) with cardiometabolic risk factors in a nationally representative sample of healthy adolescents.

METHODS

This nationwide survey was conducted among a stratified multi-stage probability sample of students, aged 10-18 years, from 27 provinces of Iran. Those students with history of any acute or chronic diseases, any medication use, as well as active or passive smoking were not included to the current study. Dietary and physical activity habits were documented by valid questionnaires. Physical examination and blood sampling were conducted under standard protocols. AQI data were obtained from air pollution monitoring sites from the entire country by considering air pollutants concentration, which includes all provincial counties containing different clusters.

RESULTS

The study participants consisted of 1413 students (48.8% boys) with a mean (SD) age of 14.81±2.48 years. The mean AQI level was 285.37±30.11 at national levels. After adjustment for confounding factors including age, sex, and anthropometric measures, as well as for dietary and physical activity habits, multiple linear regressions based on correlation of coefficients of the AQI with cardiometabolic risk factors showed significant positive correlations of AQI with systolic blood pressure, fasting blood glucose, total cholesterol, LDL-cholesterol, and triglycerides, as well as significant negative correlations with HDL-cholesterol. After adjustment for abovementioned confounding factors, binary logistic regressions analyses showed that AQI increased the risk of abnormal levels of some risk factors as elevated levels of systolic blood pressure, total cholesterol, and triglycerides.

CONCLUSION

The associations of low air quality with some cardiometabolic factors in the current survey, although not strong, might be considered as an evidence of the adverse cardiometabolic consequences of exposure to air pollutants in the pediatric age group, and predisposing them to earlier development of non-communicable diseases.

Significant associations between hemostatic/fibrinolytic systems and accumulation of cardiovascular risk factors in Japanese elementary schoolchildren

The aim of this study was to establish the reference values of hemostatic/fibrinolytic markers and investigate their relationship with physical constitution and cardiovascular risk factors in a normal schoolchildren population. This study comprised 148 healthy Japanese children aged 9-10 years (males 73; females 75). We performed laboratory tests including blood levels of leptin, high-sensitive C-reactive protein (hs-CRP), hemostatic and fibrinolytic markers [plasminogen activator inhibitor 1 (PAI-1), coagulation factor VII (FVII), coagulation factor X (FX), fibrinogen (Fbg), protein C, protein S], as well as common biochemical markers in the morning after an overnight fast. We investigated the mean, 10th, 50th and 90th percentile values of these markers. All parameters were compared between two groups, that is those with body mass index (BMI) 90th percentile or higher and BMI less than 90th percentile, and between subgroups based on the number of cardiovascular risk factors. Multiple-linear regression was used to assess associations between these hematological parameters and the components related to metabolic syndrome (MetS). Alanine aminotransferase (ALT), uric acid, leptin, hs-CRP, and all hemostatic/fibrinolytic markers (PAI-1, FVII, FX, Fbg, protein C, protein S) tested were significantly higher in the group with BMI 90th percentile or higher, and increased with accumulation of cardiovascular risk factors. Multiple-linear regression analysis showed that these values were associated with one or more components related to MetS. Reference values of hemostatic/fibrinolytic markers in Japanese schoolchildren were obtained. Many hemostatic/fibrinolytic markers showed significant association with BMI and accumulation of cardiovascular risk factors in normal Japanese schoolchildren.

A double-blind randomized trial of fish oil to lower triglycerides and improve cardiometabolic risk in adolescents

OBJECTIVES

To determine the efficacy of 4 g/day fish oil to lower triglycerides and impact lipoprotein particles, inflammation, insulin resistance, coagulation, and thrombosis.

STUDY DESIGN

Participants (n = 42, age 14 ± 2 years) with hypertriglyceridemia and low-density lipoprotein (LDL) cholesterol <160 mg/dL were enrolled in a randomized, double-blind, crossover trial comparing 4 g of fish oil daily with placebo. Treatment interval was 8 weeks with a 4-week washout. Lipid profile, lipoprotein particle distribution and size, glucose, insulin, high-sensitivity C-reactive protein, interleukin-6, fibrinogen, plasminogen activator inhibitor-1, and thrombin generation were measured.

RESULTS

Baseline lipid profile was total cholesterol 194 (5.4) mg/dL (mean [SE]), triglycerides 272 (21) mg/dL, high-density lipoprotein cholesterol 39 (1) mg/dL, and LDL cholesterol 112 (3.7) mg/dl. LDL particle number was 1614 (60) nmol/L, LDL size was 19.9 (1.4) nm, and large very low-density lipoprotein/chylomicron particle number was 9.6 (1.4) nmol/L. Triglycerides decreased on fish oil treatment but the difference was not significant compared with placebo (-52 ± 16 mg/dL vs -16 ± 16 mg/dL). Large very low-density lipoprotein particle number was reduced (-5.83 ± 1.29 nmol/L vs -0.96 ± 1.31 nmol/L; P < .0001). There was no change in LDL particle number or size. There was a trend towards a lower prothrombotic state (lower fibrinogen and plasminogen activator inhibitor-1; .10 > P > .05); no other group differences were seen.

CONCLUSIONS

In children, fish oil (4 g/day) lowers triglycerides slightly and may have an antithrombotic effect but has no effect on LDL particles.

Factors associated with early platelet activation in obese children

OBJECTIVE

To investigate the factors associated with platelet activation in obese children.

DESIGN

Cross-sectional study.

SETTING

Department of Pediatrics of Regional Hospital N∘ 1 of Mexican Institute of Social Security in Morelia, Michoacán, Mexico.

PARTICIPANTS

79 obese and 64 non-obese children between the ages of 5 and 10 years.

MAIN OUTCOMES MEASURES

Obese children (body mass index [BMI] >85 in growth curves for Centers for Disease Control/National Center for Health Statistics), and the control group of 64 non-obese children (percentile <85), % body fat, platelet activation was assessed by sP-selectin. Other measures were leptin, uric acid (UA), von Willebrand Factor (vWF), plasminogen activator inhibitor (PAI-1), lipid profile, and glucose.

RESULTS

Obese children displayed higher plasma sP-selectin, leptin, PAI-1, and vWF than non-obese children. In the univariate logistic regression analysis, leptin, vWF, UA, and high density lipoprotein (HDL), but not with PAI-1, were factors associated with platelet activation. By stepwise linear regression analysis adjusted by sex and age, the best predictor variables for platelet activation were leptin (β:0.381; t:4.665; P=0.0001), vWF (β:0.211; t:2.926; P=0.004), UA (β:0.166; t:2.146; P=0.034), and HDL (β:-0.215; t:-2.819; P=0.006).

CONCLUSIONS

Obese children have a higher risk of developing early platelet activation. Factors associated with platelet activation were Leptin, vWF, UA, and HDL. Further studies involving larger numbers of patients over a longer duration are needed to understand the possible molecular mechanism underlying the association between leptin, vWF, and UA and endothelial activation and/or endothelial damage/dysfunction in obese children and its influence in cardiovascular disease in adults.

Heterogeneous vascular responses to lifestyle intervention in obese Latino adolescents

BACKGROUND/OBJECTIVES

Among adolescents, obesity may increase the risk for premature cardiovascular disease (CVD). Lifestyle interventions may prevent or delay the onset of CVD through improvements in vascular health. The purpose of this study was to examine the effects of a 12-week lifestyle intervention on markers of vascular health in obese Latino youth.

SUBJECTS/METHODS

Fifteen obese Latino adolescents [body mass index (BMI) percentile=96.3±1.1%, 15.0±1.0 year, 8 females and 7 males] participated in a 12-week lifestyle intervention consisting of nutrition education and physical activity. Markers of vascular health included oxidized low-density lipoprotein (oxLDL), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and soluble endothelial leukocyte adhesion molecule-1 (sE-Selectin).

RESULTS

Relative to baseline data, the intervention resulted in lower oxLDL (-21.8%, P=0.001) and sE-Selectin (-13.3%, P=0.008) concentrations; sICAM-1 and sVCAM-1 did not change significantly. When examining overall responsiveness to change for each marker, oxLDL was reduced in 93.3%, sE-Selectin was reduced in 78.6%, and sICAM-1 was reduced in 71.4% of participants, respectively, whereas sVCAM-1 was reduced in only 42.9% of participants following lifestyle. Using a composite change score (summed change in four markers) for each participant there was an improvement in at least three of four markers among 64% of participants; this was confirmed by principal component analysis.

CONCLUSIONS

Therefore, although improvements in the vascular health of obese youth were observed, the vascular response to lifestyle intervention may be heterogeneous. Further investigation into the mechanisms mediating the heterogeneity in vascular response to lifestyle intervention is warranted.

Infectious burden and atherosclerosis: A clinical issue

Atherosclerotic cardiovascular diseases, chronic inflammatory diseases of multifactorial etiology, are the leading cause of death worldwide. In the last decade, more infectious agents, labeled as “infectious burden”, rather than any single pathogen, have been showed to contribute to the development of atherosclerosis through different mechanisms. Some microorganisms, such as Chlamydia pneumoniae (C. pneumoniae), human cytomegalovirus, etc. may act directly on the arterial wall contributing to endothelial dysfunction, foam cell formation, smooth muscle cell proliferation, platelet aggregation as well as cytokine, reactive oxygen specie, growth factor, and cellular adhesion molecule production. Others, such as Helicobacter pylori (H. pylori), influenza virus, etc. may induce a systemic inflammation which in turn may damage the vascular wall (e.g., by cytokines and proteases). Moreover, another indirect mechanism by which some infectious agents (such as H. pylori, C. pneumoniae, periodontal pathogens, etc.) may play a role in the pathogenesis of atherosclerosis is molecular mimicry. Given the complexity of the mechanisms by which each microorganism may contribute to atherosclerosis, defining the interplay of more infectious agents is far more difficult because the pro-atherogenic effect of each pathogen might be amplified. Clearly, continued research and a greater awareness will be helpful to improve our knowledge on the complex interaction between the infectious burden and atherosclerosis.

Does exercise intensity affect blood pressure and heart rate in obese adolescents? A 6-month multidisciplinary randomized intervention study

BACKGROUND

Aerobic exercise improves cardiovascular health in general, but whether the impact varies with exercise intensity is not clear.

OBJECTIVE

The aim of the current study was to compare the effects of a high-intensity aerobic exercise training (HIT) vs. a low-intensity aerobic exercise training (LIT) on blood pressure (BP), heart rate (HR) and heart rate variability (HRV) in obese adolescents.

METHODS

Forty-three (13-18 years) Tanner stage (III-IV) matched obese adolescents were studied in a randomized trial of either HIT (corresponding to the ventilatory threshold I; n = 20) or LIT (corresponding to 20% below the ventilatory threshold I; n = 23) programme for a period of 6 months. All participants also received a multidisciplinary therapy that included nutritional, psychological and clinical counselling. Both HIT and LIT sessions were isocaloric, with energy expenditure set at 350 kcal. BP, HR and HRV were measured along with markers of body adiposity and insulin resistance before and after the respective interventions.

RESULTS

The participants in both groups had similar physical and clinical characteristics. After the 6-month intervention, systolic, diastolic and mean BP decreased (P < 0.05, for all) similarly in both groups, whereas waist circumference, HR and HRV showed beneficial changes only in the HIT group (P < 0.05).

CONCLUSION

Aerobic exercise training set at a high intensity compared with the low intensity appears to have additional benefits on abdominal obesity and cardiovascular health in that it enhances the parasympathetic and autonomic modulation of the heart in obese adolescents.

Arsenic Exposure and Subclinical Endpoints of Cardiovascular Diseases

Mechanistic evidence suggests that arsenic exposure from drinking water increases the production of reactive oxygen species and influences inflammatory responses and endothelial nitric oxide homeostasis. These arsenic-induced events may lead to endothelial dysfunction that increases the risk of atherosclerosis and cardiovascular disease. We reviewed accumulating epidemiologic evidence that evaluated the association between arsenic exposure and intermediate markers and subclinical measures that predict future cardiovascular risk. Cross-sectional studies have indicated positive associations between high or low-to-moderate levels of arsenic exposure with indices of subclinical atherosclerosis, QT interval prolongation, and circulating markers of endothelial dysfunction. The evidence is limited for other intermediate endpoints such as markers of oxidative stress and inflammation, QT dispersion, and lipid profiles. Prospective studies are needed to enhance the causal inferences of arsenic's effects on subclinical endpoints of cardiovascular disease, especially at lower arsenic exposure levels.

Association between psychosocial distress with cardio metabolic risk factors and liver enzymes in a nationally-representative sample of Iranian children and adolescents: the CASPIAN-III study

Background

The present study was designed to evaluate association of psychosocial distress with cardio metabolic risk factors and liver enzymes in Iranian children and adolescents.

Method

This nationwide study was conducted as the third survey of the school-based surveillance system that was conducted among 5593 school students, 10–18 years in Iran. High triglyceride (TG), high fasting blood sugar (FBS), high total cholesterol (TC), high low-density lipoprotein cholesterol (LDL-C), low high-density lipoprotein cholesterol (HDL-C), hypertension (HTN), generalized obesity and abdominal obesity were considered as cardio metabolic risk factors and alanine transaminase (ALT) and aspartate aminotransferase (AST) were considered as liver enzymes. Data were analyzed using multiple logistic regression (MLR) analysis.

Result

Psychosocial distress was detected in2027 (71.2%) of boys and 1759 (63.3%) of girls. Among boys, the mean of LDL, AST and DBP were higher and the mean FBS and HDL were lowering those with psychiatric distress than their other counterparts. Girls with psychosocial distress had significantly higher mean of HDL and FBS than those without psychiatric distress. Psychosocial distress significantly increased the odds of high LDL (OR = 2.36, 95%CI 1.53, 3.64), high FBS (OR = 1.23, 95%CI 1.02, 1.49) and low HDL (OR = 1.65, 95%CI 1.41, 1.95).

Conclusion

Psychosocial distress in adolescents is associated with increased risk of some cardio metabolic risk factors.

Oxidative stress and triglycerides as predictors of subclinical atherosclerosis in prediabetes

BACKGROUND

The role of triglycerides in early preclinical atherosclerosis is controversial. Antioxidant markers may be associated with triglyceride levels in early preclinical atherosclerosis especially when fasting plasma glucose is raised.

METHODS

This cross-sectional study included 127 participants attending the Diabetes Screening Clinic, Charles Sturt University, Australia.

RESULTS

Serum 8-hydroxy-2-deoxy-guanosine (8-OHdG) was significantly greater in the impaired fasting glucose (IFG) group compared with the control group (536.7 pg/ml ± 249.8 versus 171.4 pg/ml ± 96.9, respectively). The increase in 8-OHdG was associated with a mildly non-significant elevation in low-density lipoprotein level (3.2 ± 1.1 mmol/l) and a poor level of high-density lipoprotein (1.31 ± 0.3 mmol/l) in the IFG group. However, a significant increase in triglycerides (1.6 ± 0.97 mmol/l; P < 0.05) in the IFG group was observed. Erythrocyte reduced glutathione (GSH) levels in the IFG group, although increased, were also not significantly different to control.

CONCLUSION

A significant increase in 8-OHdG is associated with increased levels of triglycerides in the absence of significant changes in reduced GSH and normal levels of cholesterol in the IFG cohort, suggesting that oxidative stress may be present and indicative of subclinical atherosclerosis.

Gender and the active smoking and high-sensitivity C-reactive protein relation in late adolescence

C-reactive protein (CRP), smoking, and oral contraceptive (OC) use are associated with CVD risk in adults. This study examines the effect of smoking on high-sensitivity CRP (hs-CRP) levels, and the interactive effects of sex and OC use on this relationship in an adolescent cohort. A total of 1,050 adolescents (mean age 17 ± 0.25 years) from the Western Australian Pregnancy Cohort (Raine) Study had anthropometric, lifestyle, and metabolic measures recorded. The association between smoking status and log-transformed hs-CRP was analyzed using multivariable Tobit linear regression models, with adjustment for adiposity, lifestyle, and early-life confounders. A three-level variable (girls not using OCs, girls using OCs, and boys) was employed to assess the interactive effects of sex, OC use, and smoking. Smoking associated with higher hs-CRP levels in girls not using OCs (b = 0.571; P = 0.001), but not in girls using OCs (b = -0.117; P = 0.598) or in boys (b = 0.183; P = 0.2). OC use in nonsmoking girls was the strongest factor associated with higher hs-CRP levels (b = 1.189; P < 0.001). This study has demonstrated a more robust effect of smoking on hs-CRP levels in girls not using OCs compared with boys. The findings may explain why CVD risk conferred by smoking is higher in women than in men.

Associations of cardiac structure with obesity, blood pressure, inflammation, and insulin resistance in African-American adolescents

To determine if obesity, blood pressure (BP), markers of inflammation, and insulin resistance are associated with cardiac structure in African-American adolescents, a cross-sectional study was performed on a cohort oversampled for high BP and obesity. Measurements included the following: anthropometrics, BP, homeostasis model assessment (HOMA) to assess insulin resistance, high-sensitivity C-reactive protein, and plasma adipokines (adiponectin, interleukin-6, plasminogen activator inhibitor-1). Echocardiogram measurements were left-ventricular mass index (LVMI) (g/m(2.7)), LV relative wall thickness (LVRWT), left-atrial diameter index [LADI (mm/m)], and LV diastolic time intervals. LADI (r (2) = 0.25) was associated with body mass index (BMI) systolic BP (SBP) and female sex. LVMI (r (2) = 0.35) variation was associated with BMI SBP, heart rate, age, and male sex. LVRWT (r (2) = 0.05) was associated with HOMA. Tissue diastolic intervals were not associated with any risk factor. Inflammatory markers and adipokines were associated with BMI but were not independently associated with any echocardiographic measures. In African-American adolescents, BMI and SBP, but not inflammatory markers or adipokines, are important correlates of LA size and LVM.

Heart rate variability and its relationship with central and general obesity in obese normotensive adolescents

Objective:

To analyze the relationship between the heart rate variability parameters and the indicators of central and general obesity in obese normotensive adolescents.

Methods:

Seventy-four 13 to 18 year-old obese normotensive adolescents participated in this study. The indicators analyzed for central and general obesity were waist circumference and body mass index, respectively. Heart rate variability was obtained by heart rate monitoring. For this, the adolescents remained in a supine position for 7 minutes with controlled breathing. Parameters were obtained in time domain (standard deviation of all the RR intervals, root mean square of successive differences between the normal adjacent RR intervals and the percentage of adjacent intervals with more than 50ms) and frequency domain variables (low and high frequency bands and the sympathovagal balance).

Results:

After adjustments for gender, age, and cardiorespiratory fitness, a negative correlation between the waist circumference and the root mean square of successive differences between the normal adjacent RR intervals (ß=-1.51; standard error=0.56; p<0.05) and the percentage of adjacent intervals with more than 50 ms (ß=-0.96; standard error=0.34; p<0.05) were observed, while the body mass index showed no significant correlation with any heart rate variability parameter (p>0.05).

Conclusion:

Central obesity is a better discriminator than general obesity of autonomic cardiac dysfunction in obese normotensive adolescents

First report on simplified diagnostic criteria for pre-hypertension and hypertension in a national sample of adolescents from the Middle East and North Africa: the CASPIAN-III study

OBJECTIVE

This study aimed to simplify the diagnostic criteria of pre-hypertension (pre-HTN) and hypertension (HTN) in the pediatric age group, and to determine the accuracy of these simple indexes in a nationally-representative sample of Iranian children and adolescents.

METHOD

The diagnostic accuracy of the indexes of systolic blood pressure-to-height ratio (SBPHR) and diastolic BPHR (DBPHR) to define pre-HTN and HTN was determined by the area under the curve of the receiver operator characteristic curves.

RESULTS

The study population consisted of 5,738 Iranian students (2,875 females) with mean (SD) age of 14.7 (2.4) years. The prevalences of pre-HTN and HTN were 6.9% and 5.6%. The optimal thresholds for defining pre-HTN were 0.73 in males and 0.71 in females for SBPHR, and 0.47 in males and 0.45 in females for DBPHR, respectively. The corresponding figures for HTN were 0.73, 0.71, 0.48, and 0.46, respectively. In both genders, the accuracies of SBPHR and DBPHR in diagnosing pre-HTN and HTN were approximately 80%.

CONCLUSIONS

BPHR is a valid, simple, inexpensive, and accurate tool to diagnose pre-HTN and HTN in adolescents. The optimal thresholds of SBPHR and DBPHR were consistent with the corresponding figures in other populations of children and adolescents with different racial and ethnic backgrounds. Thus, it is suggested that the use of these indexes can be generalized in programs aiming to screen elevated blood pressure in the pediatric age group.

Abdominal adiposity, insulin resistance, and oxidized low-density lipoproteins in Latino adolescents

Abdominal obesity and insulin resistance (IR) place youth at higher risk for premature cardiovascular disease (CVD), but the underlying mechanisms are not clear. In adults, abdominal obesity and IR contribute to the oxidation of low-density lipoprotein (LDL). Whether similar mechanisms are operational in Latino adolescents is unknown. Therefore, we determined whether IR and abdominal adiposity are associated with higher oxLDL concentrations in Latino adolescents. Data from 123 Latino adolescents (16.3 ± 2.5 years; female = 74) were used for the present analysis. Participants were assessed for waist circumference, fasting serum oxLDL, and insulin sensitivity by the whole body insulin sensitivity index. In separate linear regression models adjusting for age and sex, both waist circumference and insulin sensitivity were significant predictors of oxLDL (β = 1.9; p = 0.002; R2 = 0.13, β = -1.7; p = 0.006; R2 = 0.11, respectively). When insulin sensitivity and waist circumference were included in the same model, both remained independent predictors of oxLDL (β = 1.7; p = 0.016 and, β = -1.5; p = 0.055, respectively; R2 = 0.16). These results suggest that insulin resistance and abdominal adiposity are associated with higher levels of LDL oxidation which may be a mechanism contributing to increased CVD risk in Latino adolescents.

Adipocytokines in relation to cardiovascular disease

Adipose tissue can be considered as a huge gland producing paracrine and endocrine hormones, the adipo(cyto)kines. There is growing evidence that these adipo(cyto)kines may link obesity to cardiovascular diseases. The excessive adipocyte hypertrophy in obesity induces hypoxia in adipose tissue. This leads to adiposopathy, the process that converts "healthy" adipose tissue to "sick" adipose tissue. This is accompanied by a change in profile of adipo(cyto)kines released, with less production of the "healthy" adipo(cyto)kines such as adiponectin and omentin and more release of the "unhealthy" adipo(cyto)kines, ultimately leading to the development of cardiovascular diseases. The present review provides a concise and general overview of the actual concepts of the role of adipo(cyto)kines in endothelial dysfunction, hypertension, atherosclerosis and heart diseases. The knowledge of these concepts may lead to new tools to improve health in the next generations.

Association of breakfast intake with cardiometabolic risk factors

OBJECTIVE

this study aimed to evaluate the association of breakfast intake with cardiometabolic risk factors in a nationally-representative sample of Iranian pediatrics.

METHODS

the study participants considered of 5,625 school students aged 10-18 years, studied in the third survey of the national school-based surveillance system (CASPIAN-III). They were classified into three groups based on the number of days they ate breakfast: "regular breakfast eater" (6-7days/week), "often breakfast eater" (3-5days/week), and "seldom breakfast eater" (0-2 days/week). Metabolic syndrome (MetS) was defined based on the Adult Treatment Panel III (ATP III) criteria modified for the pediatric age group. Moreover, high total cholesterol, high low-density lipoprotein cholesterol (LDL-C) and generalized obesity were included as other cardiometabolic risk factors. Multiple logistic regression analyses were used to evaluate the association between the breakfast intake category and cardiometabolic risk factors.

RESULTS

the number of subjects classified as "regular", "often" and "seldom" breakfast eaters were 2,653(47.3%), 1,327(23.7%) and 1,624(29.0%), respectively. The average of triglycerides (TG), LDL-C, systolic blood pressure (SBP) and body mass index (BMI) were higher in the "seldom breakfast eater" group (P for trend<0.001), whereas the mean of high-density lipoprotein cholesterol (HDL-C) was lower in this group than their other counterparts. Seldom breakfast eaters had an increased risk of obesity, elevated TG and LDL-C, as well as low HDL-C compared to "regular breakfast eaters". The risk of MetS was significantly increased in subjects who seldom ate breakfast (OR 1.96, 95% CI 1.18-3.27).

CONCLUSIONS

skipping breakfast is associated with increased risk of MetS and other cardiometabooic factors in children and adolescents. Promoting the benefit of eating breakfast could be a simple and important implication to prevent these risk factors.

Lifestyle intervention improves lipoprotein particle size and distribution without weight loss in obese Latino adolescents

Childhood obesity is associated with a pro-atherogenic phenotype contributing to increased cardiovascular disease (CVD) risk. This single-arm pilot study examined the effects of a lifestyle intervention on lipoprotein particle size and cholesterol distribution in obese Latino adolescents. Fifteen obese Latino adolescents (15.0 ± 1.0 years) completed a 12-week nutrition education and exercise intervention. Low-density lipoprotein (LDL) particle size and distribution of cholesterol in lipoprotein subclasses were determined via polyacrylamide gel electrophoresis. The intervention resulted in increases in mean LDL particle size (269.3 ± 3.4 to 271.6 ± 2.9 Å, P = 0.0003) and cholesterol in large high-density lipoprotein (HDL) subfractions (22.4 ± 11.2 to 26.8 ± 10.6% area, P = 0.007) along with decreases of cholesterol in small LDL (1.6 ± 2.0 to 0.6 ± 1.2% area, P < 0.01) and HDL subfractions (23.2 ± 9.4 to 19.0 ± 6.7% area, P = 0.05). These improvements were observed independent of changes in weight (90.7 ± 26.2 to 89.9 ± 27.8 kg, P > 0.05) and suggest that lifestyle modification in obese youth may reduce cardiovascular risk by shifting lipoprotein particle size and cholesterol distribution to a less atherogenic phenotype.

Severe obesity in children and adolescents: identification, associated health risks, and treatment approaches: a scientific statement from the American Heart Association

Severe obesity afflicts between 4% and 6% of all youth in the United States, and the prevalence is increasing. Despite the serious immediate and long-term cardiovascular, metabolic, and other health consequences of severe pediatric obesity, current treatments are limited in effectiveness and lack widespread availability. Lifestyle modification/behavior-based treatment interventions in youth with severe obesity have demonstrated modest improvement in body mass index status, but participants have generally remained severely obese and often regained weight after the conclusion of the treatment programs. The role of medical management is minimal, because only 1 medication is currently approved for the treatment of obesity in adolescents. Bariatric surgery has generally been effective in reducing body mass index and improving cardiovascular and metabolic risk factors; however, reports of long-term outcomes are few, many youth with severe obesity do not qualify for surgery, and access is limited by lack of insurance coverage. To begin to address these challenges, the purposes of this scientific statement are to (1) provide justification for and recommend a standardized definition of severe obesity in children and adolescents; (2) raise awareness of this serious and growing problem by summarizing the current literature in this area in terms of the epidemiology and trends, associated health risks (immediate and long-term), and challenges and shortcomings of currently available treatment options; and (3) highlight areas in need of future research. Innovative behavior-based treatment, minimally invasive procedures, and medications currently under development all need to be evaluated for their efficacy and safety in this group of patients with high medical and psychosocial risks.

High-density lipoprotein subfractions display proatherogenic properties in overweight and obese children

BACKGROUND

In adults, obesity-driven inflammation can lead to increased cardiovascular disease (CVD). However, information regarding childhood obesity and its inflammatory sequelae is less well defined. Serum amyloid-A (SAA) is an inflammatory molecule that rapidly associates with high-density lipoproteins (HDLs) and renders them dysfunctional. Therefore, SAA may be a useful biomarker to identify increased CVD potential in overweight and obese children.

METHODS

Young Hearts 2000 is a cross-sectional cohort study in which 92 children who were obese were matched for age and sex with 92 overweight and 92 lean children. HDL(2) and HDL(3) (HDL(2&3)) were isolated from plasma by a three-step rapid-ultracentrifugation procedure. SAA was measured in serum and HDL(2&3) by an enzyme-linked immunosorbent assay procedure, and the activities of cholesterol ester transfer protein (CETP) and lecithin cholesteryl acyltransferase (LCAT) were measured by fluorimetric assays.

RESULTS

Trends across the groups indicated that SAA increased in serum and HDL(2&3) as BMI increased, as did HDL(2)-CETP and HDL(2)-LCAT activities.

CONCLUSION

These results have provided evidence that overweight and obese children are exposed to an inflammatory milieu that impacts the antiatherogenic properties of HDL and that could increase CVD risk. This supports the concept that it is important to target childhood obesity to help minimize future cardiovascular events.

No detection of Helicobacter pylori in atherosclerotic plaques in end stage renal disease patients undergoing kidney transplantation

Chronic infection known to be a predisposing factor for the development of atherosclerosis. Several studies have found a possible role of Helicobacter pylori in the pathogenesis of atherosclerosis. The aim of this study was to investigate the presence of H. pylori in atherosclerotic plaques in iliac arteries in 25 end stage renal disease (ESRD) patients undergoing kidney transplantation. Esophagogastroduodenoscopy was performed in all patients before transplantation. Biopsy specimens obtained from gastric antrum were sent for pathologic evaluation. Gastric H. pylori infection was confirmed by microscopic assessment and rapid urease test. Arterial specimens were obtained from iliac arteries during kidney transplantation. Presence of H. pylori DNA in atherosclerotic plaques and healthy vessel samples was evaluated by the polymerase chain reaction (PCR). The mean age of patients was 44.1 ± 22.6 years. Risk factors in patients with atherosclerosis were hypertension (68%), diabetes mellitus (20%), hyperlipidemia (20%), positive family history (16%). Atherosclerotic plaques were found in 21 (84%) patients. PCR analysis did not detect H. pylori in any case. There was a significant relationship of atherosclerosis with hypertension (P = 0.006) but not with diabetes mellitus and hyperlipidemia (P = 0.5). There was no significant relationship between atherosclerosis and gastric H. pylori infection (P = 0.6). This study revealed no association between the presence of H. pylori as a pathogen of vessel walls and atherosclerosis in ESRD.