Healthy Pediatric Cohort Research Articles

Metabolic syndrome in a Mediterranean pediatric cohort: prevalence using International Diabetes Federation–derived criteria and associations with adiponectin and leptin

The aims of the study were to determine the prevalence of metabolic syndrome (MS) components and examine associations with adipokine concentrations in a healthy pediatric cohort. A cross-sectional study of 1138 children (53% girls; mean age of all participants, 11.2 ± 0.7 years) was performed. Anthropometric and medical information was obtained; and a fasting blood sample was used to measure glucose, insulin, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, leptin, and adiponectin serum concentrations. Insulin resistance was assessed by the insulin resistance homeostasis model assessment. Body weight status (normal, overweight, and obese) was determined according to the International Obesity Task Force. Estimation of the MS was based on the International Diabetes Federation definition. The prevalence of the MS was 0.7% of children, all of whom were obese. Frequency of abdominal obesity, high fasting glucose, elevated triglycerides, low high-density-lipoprotein cholesterol, and elevated blood pressure was 4.8%, 4.7%, 0, 12.3%, and 33%, respectively. Body mass index (BMI) and z-BMI score increased significantly as the number of cardiometabolic risk factors increased. Regression analysis revealed that adiponectin ( β = −0.501, P = .003) and leptin ( β = 0.184, P < .0001) independently predicted the number of MS features. This finding was no longer significant after adjustment for BMI. In the present study, we provide the first estimate of the prevalence of the MS among healthy periadolescents in Greece using the International Diabetes Federation criteria. The MS prevalence was low, with elevated blood pressure being the most dominant feature. Finally, associations with adipokines are mediated by BMI.

Reference Values for Myocardial Two-Dimensional Strain Echocardiography in a Healthy Pediatric and Young Adult Cohort

The accurate evaluation of intrinsic myocardial contractility in children with or without congenital heart disease (CHD) has turned out to be a challenge. Two-dimensional strain echocardiographic (2DSTE) imaging or two-dimensional speckle-tracking echocardiographic imaging appears to hold significant promise as a tool to improve the assessment of ventricular myocardial function. The aim of this study was to estimate left ventricular myocardial systolic function using 2DSTE imaging in a large cohort consisting of healthy children and young adults to establish reference strain values. Transthoracic echocardiograms were acquired in 195 healthy subjects (139 children, 56 young adults) and were retrospectively analyzed. Longitudinal, circumferential, and radial peak systolic strain values were determined by means of speckle tracking. Nonlinear regression analysis was performed to assess the effect of aging on these 2DSTE parameters. There was a strong, statistically significant second-order polynomial relation (P < .001) between global peak systolic strain parameters and age. Global peak systolic strain values were lowest in the youngest and oldest age groups. This is the first report to establish age-dependent reference values per cardiac segment for myocardial strain in all three directions assessed using 2DSTE imaging in a large pediatric and young adult cohort. There is a need to use age-specific reference values for the adequate interpretation of 2DSTE measurements.

Maturational and Growth-Related Changes in Left Ventricular Longitudinal Strain and Strain Rate Measured by Two-Dimensional Speckle Tracking Echocardiography in Healthy Pediatric Population

We aimed to evaluate myocardial strain and strain rate (SR) by novel 2-dimensional speckle tracking echocardiography in a large pediatric cohort (1) to establish their normal values and (2) to discern the influence of maturation and cardiac growth on them. Echocardiograms of 284 consecutive subjects of a healthy pediatric cohort aged between birth and 18 years were analyzed by vector velocity imaging software to measure longitudinal systolic strain (epsilon) and systolic and diastolic SR in left ventricular septal and lateral segments. Regression analysis was performed to determine the effect of aging and cardiac growth on epsilon and SR. Longitudinal epsilon (septal -18.30% +/- 6.67% and lateral -20.68% +/- 8.08%) did not change significantly with maturation and declining heart rate from birth to 18 years. Systolic and early diastolic SR declined until age 5 to 10 years. Longitudinal epsilon significantly (P < .05) correlated with left ventricular growth. This study establishes reference values for longitudinal epsilon and SR and reveals that epsilon is relatively independent of maturational changes, lending it as a tool for cardiac evaluation across differing ages in pediatric subjects.