Arterial distensibility is reduced in overweight pre- and early pubescent children

Is There a Role for Imaging Youth at Risk of Atherosclerosis?

PURPOSE OF REVIEW

Cardiovascular (CV) risk factors such as dyslipidemia, hypertension, diabetes, and obesity are associated with an increased risk for CV events in adults. Noninvasive measures of vascular health are associated with these CV events and can potentially help risk stratify children with CV risk factors. The purpose of this review is to summarize recent literature regarding vascular health in children with cardiovascular risk factors.

RECENT FINDINGS

Adverse changes in pulse wave velocity, pulse wave analysis, arterial distensibility, and carotid intima-media thickness are seen in children with CV risk factors supporting potential utility in risk stratification. Assessing vascular health in children can be challenging due to growth-related changes in vasculature, multiple assessment modalities, and differences in normative data. Vascular health assessment in children with cardiovascular risk factors can be a valuable tool for risk stratification and help identify opportunities for early intervention. Future areas of research include increasing normative data, improving conversion of data between different modalities, and increasing longitudinal studies in children linking childhood risk factors to adult CV outcomes.

Long-term trajectories of BMI predict carotid stiffness and plaque volume in type 2 diabetes older adults: a cohort study

BACKGROUND

High body mass index (BMI) is a risk factor for type 2 diabetes and cardiovascular disease. However, its relationships with indices of carotid stiffness and plaque volume are unclear. We investigated associations of long-term measurements of BMI with indices of carotid stiffness and atherosclerosis among non-demented diabetes patients from the Israel Diabetes and Cognitive Decline (IDCD) study.

METHODS

Carotid ultrasound indices [carotid intima media thickness (cIMT), distensibility, elastography and plaque volume] were assessed in N = 471 participants. Mean BMI across all MHS diabetes registry measurements and trajectories of BMI were calculated. BMI was categorized into three trajectory groups representing: a relatively stable normal weight (n = 185, 44%), overweight trajectory (n = 188, 44.8%) and a trajectory of obesity (n = 47, 11.2%). Linear and logistic regressions estimated associations of carotid indices with mean BMI and BMI trajectories.

RESULTS

Compared to the normal weight trajectory, an obesity trajectory was associated with carotid distensibility (β = - 3.078, p = 0.037), cIMT (β = 0.095, p = 0.004), and carotid elastography (β = 0.181, p = 0.004) but not with plaque volume (β = 0.066, p = 0.858). Compared with the normal weight trajectory, an obesity trajectory was associated with increased odds for impaired carotid distensibility (OR = 2.790, p = 0.033), impaired cIMT (OR = 5.277, p = 0.001) and large carotid plaque volume (OR = 8.456, p = 0.013) but not with carotid elastography (OR = 1.956, p = 0.140). Mean BMI was linearly associated with Distensibility (β = - 0.275, p = 0.005) and cIMT (β = 0.005, p = 0.026).

CONCLUSIONS

Long-term measurements of adiposity are associated with indices of carotid stiffness and plaque volume among older type 2 diabetes adults.

What is the effect of ADHD stimulant medication on heart rate and blood pressure in a community sample of children?

OBJECTIVE

This study examines the effect of ADHD (attention deficit hyperactivity disorder) diagnosis and stimulant medication for ADHD treatment on child heart rate (HR) and blood pressure (BP) in a community sample compared to children without ADHD.

METHODS

Data came from the HBEAT Study. From 49 schools, 2013 participants from southern Ontario in grades 5-8 were included. Linear regression analyses examined the effects of ADHD medications on systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate adjusting for age, sex and body mass index (BMI).

RESULTS

Compared to non-ADHD children and adjusting for age, sex and BMI, children with ADHD on stimulant medication had a 12.3-bpm higher HR, and 3.0-mmHg higher SBP and DBP (all statistically significant). Children with ADHD on no stimulant medication had no differences in HR and BP compared to those children without a diagnosis of ADHD.

CONCLUSION

Stimulant medications used to treat ADHD are associated with elevated HR and higher BP. While it is unknown whether children on ADHD medications may be at risk for longer-term cardiovascular issues, this study supports the need to examine the long-term consequences of ADHD medication.

Arterial stiffness in children with and without probable developmental coordination disorder

BACKGROUND

Children with cardiovascular disease risk factors demonstrate adverse arterial alterations that are predictive of cardiovascular morbidity and mortality in adults. Children with developmental coordination disorder (DCD) are at cardiovascular risk as they are more likely to be obese and inactive.

AIM

The purpose of this study was to assess arterial structure and function in children with and without probable DCD (p-DCD).

METHODS

A cross-sectional study of 33 children with p-DCD (22 male) and 53 without (30 male). The Movement Assessment Battery for Children was used to classify those with p-DCD. Adiposity was assessed using the BOD POD. Compliance, distensibility, and intima-media thickness were measured at the common carotid artery (CCA). ECG R-wave-to-toe pulse wave velocity (PWV) was also measured.

RESULTS

Compared to controls, males with p-DCD had lower CCA distensibility (p=0.034) and higher PWV (p=0.001). No differences were evident in females. Body fat percent was a significant predictor of CCA distensibility and removed the effect of p-DCD on PWV in males.

CONCLUSIONS

The present study demonstrates augmented arterial stiffness in males with p-DCD, likely attributed to body fat. These findings underscore the importance of targeted interventions in children with p-DCD, specifically males, in order to prevent future cardiovascular risk.

The association between arterial properties and blood pressure in children

Elevated blood pressure (BP) in adults is associated with increased arterial stiffness and thickness; however, its effect on arterial health in a pediatric population is less understood. The purpose of this study was to identify the relationship between childhood BP and arterial markers of arteriosclerotic progression. The study consisted of 106 children across a wide range of BP values divided into 2 BP groups: high BP (HBP; ≥ 95th percentile; n = 21) and normal BP (NBP; < 90th percentile; n = 85) based on consistent automated BP measures taken at 2 time points. The laboratory examination involved systemic pulse wave velocity (PWV), common carotid artery (CCA) intima media thickness (IMT) and distensibility, as well as body mass index (BMI) and pubertal maturation. BMI and heart rate, as well as PWV (HBP: n = 15 and NBP: n = 56), were higher in the HBP group (p < 0.001) with no difference between groups for both CCA distensibility and IMT (HBP: n = 21 and NBP: n = 83). Multivariate linear regression revealed that BP group (p = 0.003) was an independent predictor of PWV after controlling for age, sex, BMI, heart rate, and maturation. Our findings demonstrate a higher systemic PWV with no difference in CCA IMT or distensibility in children with elevated BP. Hence, markers of cardiovascular disease risk are augmented in healthy children with elevated BP.

Cardiovascular disease risk in healthy children and its association with body mass index: systematic review and meta-analysis

OBJECTIVES

To describe the association and its magnitude between body mass index category, sex, and cardiovascular disease risk parameters in school aged children in highly developed countries.

DESIGN

Systematic review and meta-analysis. Quality of included studies assessed by an adapted version of the Cochrane Collaboration's risk of bias assessment tool. Results of included studies in meta-analysis were pooled and analysed by Review Manager version 5.1.

DATA SOURCES

Embase, PubMed, EBSCOHost's cumulative index to nursing and allied health literature, and the Web of Science databases for papers published between January 2000 and December 2011.

REVIEW METHODS

Healthy children aged 5 to 15 in highly developed countries enrolled in studies done after 1990 and using prospective or retrospective cohort, cross sectional, case-control, or randomised clinical trial designs in school, outpatient, or community settings. Included studies had to report an objective measure of weight and at least one prespecified risk parameter for cardiovascular disease.

RESULTS

We included 63 studies of 49 220 children. Studies reported a worsening of risk parameters for cardiovascular disease in overweight and obese participants. Compared with normal weight children, systolic blood pressure was higher by 4.54 mm Hg (99% confidence interval 2.44 to 6.64; n=12 169, eight studies) in overweight children, and by 7.49 mm Hg (3.36 to 11.62; n=8074, 15 studies) in obese children. We found similar associations between groups in diastolic and 24 h ambulatory systolic blood pressure. Obesity adversely affected concentrations of all blood lipids; total cholesterol and triglycerides were 0.15 mmol/L (0.04 to 0.25, n=5072) and 0.26 mmol/L (0.13 to 0.39, n=5138) higher in obese children, respectively. Fasting insulin and insulin resistance were significantly higher in obese participants but not in overweight participants. Obese children had a significant increase in left ventricular mass of 19.12 g (12.66 to 25.59, n=223), compared with normal weight children.

CONCLUSION

Having a body mass index outside the normal range significantly worsens risk parameters for cardiovascular disease in school aged children. This effect, already substantial in overweight children, increases in obesity and could be larger than previously thought. There is a need to establish whether acceptable parameter cut-off levels not considering weight are a valid measure of risk in modern children and whether methods used in their study and reporting should be standardised.

Baroreflex sensitivity is reduced in adolescents with probable developmental coordination disorder

Developmental coordination disorder (DCD) is a neurodevelopmental condition characterized by poor motor skills leading to a significant impairment in activities of daily living. Compared to typically developing children, those with DCD are less fit and physically active, and have increased body fat. This is an important consequence as both sedentary lifestyle and obesity are risk factors for cardiovascular disease. One indicator of cardiovascular health is baroreflex sensitivity (BRS), which is a measure of short term blood pressure (BP) regulation and is partly accomplished through changes in heart rate. Diminished BRS is predictive of future cardiovascular morbidity and mortality. The purpose of this study was to compare BRS in typically developing (TD) adolescents with probable DCD (pDCD) or suspect pDCD (spDCD) adolescents (13-14 years of age). Percentile scores on the Movement Assessment Battery for Children, 2nd edition, assessed at two time points were averaged and used to classify participants into the following groups: pDCD ≤ 5th percentile, spDCD > 5th percentile and ≤16th percentile and TD>16th percentile. Following 15 min of supine rest, 5 min of continuous beat-by-beat blood pressure (Finapres) and R-R interval were recorded (standard ECG). Spectral indices were computed using Fast Fourier Transform with transfer function analysis used to compute BRS in the low frequency region (0.04-0.15 Hz). BRS was compared between groups with an ANOVA and post hoc Bonferroni correction. BRS was reduced in the pDCD compared to the TD groups. In multivariate regression analyses predicting BRS, when pDCD and spDCD were entered as the only variables, pDCD was found to be a significant predictor of BRS (b=-6.74, p=0.016). However, when sex, VO(2) peak, and percent body fat (PBF) were entered as covariates, pDCD was no longer a predictor, while PBF approached significance (-0.32, p=0.056). Therefore, in this sample, BRS was reduced in adolescents with pDCD principally due to increased PBF.