Arterial stiffness is increased in American adolescents compared to Japanese counterparts

Evaluation of carotid artery stiffness in obese children using ultrasound radiofrequency data technology

OBJECTIVES

The goals of this study were to investigate the difference in carotid arterial stiffness in obese children compared to healthy children and to study the correlation between carotid arterial stiffness parameters and obesity using ultrasound (US) radiofrequency (RF) data technology.

METHODS

Carotid artery stiffness parameters, including the compliance coefficient, stiffness index, and pulse wave velocity, were evaluated in 71 obese patients and 47 healthy controls with US RF data technology. In addition, all participants were evaluated for fat thickness in the paraumbilical abdominal wall and fatty liver using abdominal US.

RESULTS

Compared to the control group, the blood pressure (BP), body mass index (BMI), fat thickness in the paraumbilical abdominal wall, presence of fatty liver, and carotid stiffness parameters (stiffness index and pulse wave velocity) were significantly higher in the obese group, whereas the compliance coefficient was significantly lower in the obese group. Furthermore, the pulse wave velocity was weakly positively correlated with the BMI, systolic BP, diastolic BP, and paraumbilical abdominal wall fat thickness, whereas the compliance coefficient was weakly negatively correlated with the systolic BP, BMI, and paraumbilical abdominal wall fat thickness. The presence of a fatty liver was moderately positively correlated with the BMI and weakly positively correlated with the pulse wave velocity.

CONCLUSIONS

Ultrasound RF data technology may be a sensitive noninvasive method that can be used to accurately and quantitatively detect the difference in carotid artery stiffness in obese children compared to healthy children. The detection of carotid functional abnormalities and nonalcoholic fatty liver disease in obese children should allow early therapeutic intervention, which may prevent or delay the development of atherosclerosis in adulthood.

Prediction of cardiovascular events and all-cause mortality with brachial-ankle elasticity index: a systematic review and meta-analysis

Brachial-ankle elasticity index (baEI; also known as brachial-ankle pulse wave velocity) has been proposed as a surrogate end point for cardiovascular disease. We performed a meta-analysis of longitudinal cohort studies for determining the ability of baEI to predict risk of cardiovascular events and all-cause mortality and dissecting factors influencing this predictive ability. Multiple online databases, reference lists from retrieved articles, and abstracts from international cardiovascular conventions were searched until April 2012. Longitudinal cohort studies that reported associations of baEI with clinical risk were included. Of the 18 studies included (8169 participants; mean follow-up, 3.6 years), 15 reported results on total cardiovascular events (5544 individuals), 7 on cardiovascular mortality (2274 individuals), and 9 on all-cause mortality (5097 individuals). The pooled relative risks for total cardiovascular events, cardiovascular mortality, and all-cause mortality were 2.95 (95% CI, 1.63-5.33), 5.36 (95% CI, 2.17-13.27), and 2.45 (95% CI, 1.56-3.86), respectively, for subjects with high versus low baEI (all P<0.001). An increase in baEI by 1 m/s corresponded with an increase of 12%, 13%, and 6% in total cardiovascular events, cardiovascular mortality, and all-cause mortality, respectively. We conclude that baEI is associated with increased risk of total cardiovascular events and all-cause mortality. Issues such as expansion of data to non-Asian populations, validation of path length estimation, determination of reference values, and prospective comparison with carotid-femoral pulse wave velocity remain to be resolved.

Carotid artery stiffness as an early marker of vascular lesions in children and adolescents with cardiovascular risk factors

INTRODUCTION AND OBJECTIVES

The availability of a noninvasive marker of vascular lesions that enables their detection in the preclinical phase would be of great benefit for cardiovascular disease prevention. The aim of this study was to investigate the usefulness of a range of indices of arterial wall stiffness in the common carotid artery, as derived using high-resolution Doppler ultrasonography, for identifying vascular damage in children with risk factors.

METHODS

The study involved 99 children (age, 8-16 years) divided into two groups: 65 had cardiovascular risk factors (45 obesity, 20 dyslipidemia) and 34 were controls. Family histories of cardiovascular risk factors and anthropometric and biochemical measurements were recorded. Functional parameters of arterial stiffness (i.e., arterial compliance, elastic modulus, beta stiffness index, pulse wave velocity, and augmentation index) and the intima-media thickness were also measured.

RESULTS

Some functional vascular parameters were higher in obese children than controls: there were significant differences in beta stiffness index (P< .02), elastic modulus (P< .001) and pulse wave velocity (P< .01). There was a significant difference in arterial compliance between dyslipidemics and controls (P< .05). No significant difference in intima-media thickness was found between the groups. In obese children, there were positive correlations between body mass index, systolic pressure and triglyceride levels and vascular parameters (i.e., elastic modulus and pulse wave velocity); in dyslipidemic children, triglyceride levels and the same parameters were correlated.

CONCLUSIONS

Ultrasonographic measurement of arterial stiffness is a sensitive technique that can detect vascular damage in children with cardiovascular risk factors earlier than intima-media thickness measurement.

The effect of feto-maternal size and childhood growth on left ventricular mass and arterial stiffness in Afro-Caribbean children

We hypothesized that maternal size, fetal size and childhood growth are associated with childhood blood pressure, left ventricular mass (LVM) and arterial stiffness. The Vulnerable Windows Cohort is a longitudinal study of 569 mothers and their offspring. Anthropometry was measured on each child at birth, at 6 weeks, once in 3 months upto 2 years and then every 6 months. Blood pressure and body composition were assessed in 185 children (age 11.5 years) and echocardiography performed. LVM was not associated with maternal size after adjustment for child's weight. LVM was significantly associated with faster growth in childhood and with current weight, fat mass and lean mass. Systolic blood pressure was not related to maternal, fetal or newborn anthropometry, but was positively associated with infant and childhood growth, as well as current body size and fat mass. The pulse pressure/stroke volume ratio (an index of arterial stiffness) was inversely associated with maternal size, placental volume at 20 weeks, fetal size at 35 weeks and childhood growth even after adjustment for current weight. In conclusion, LVM in childhood is positively associated with maternal height, child's current size and rate of growth. Arterial stiffness is inversely related to maternal, fetal and placental size as well as growth throughout childhood.

Vascular health in children and adolescents: effects of obesity and diabetes

The foundations for cardiovascular disease in adults are laid in childhood and accelerated by the presence of comorbid conditions, such as obesity, diabetes, hypertension, and dyslipidemia. Early detection of vascular dysfunction is an important clinical objective to identify those at risk for subsequent cardiovascular morbidity and events, and to initiate behavioral and medical interventions to reduce risk. Typically, cardiovascular screening is recommended for young adults, especially in people with a family history of cardiovascular conditions. Children and adolescents were once considered to be at low risk, but with the growing health concerns related to sedentary lifestyle, poor diet and obesity, cardiovascular screening may be needed earlier so that interventions to improve cardiovascular health can be initiated. This review describes comorbid conditions that increase cardiovascular risk in youth, namely obesity and diabetes, and describes noninvasive methods to objectively detect vascular disease and quantify vascular function and structure through measurements of endothelial function, arterial compliance, and intima-media thickness. Additionally, current strategies directed toward prevention of vascular disease in these populations, including exercise, dietary interventions and pharmacological therapy are described.