Ambulatory blood pressure monitoring in obese children: role of insulin resistance

Breastfeeding Duration and Cardiometabolic Health during Adolescence: A Longitudinal Analysis

OBJECTIVE

To investigate the longitudinal association between breastfeeding duration and cardiometabolic health, using repeated measures study design among children and adolescents.

STUDY DESIGN

This study included 634 offsprings aged 10 to 21 years (52% female) from the Early Life Exposure in Mexico to Environmental Toxicants birth cohort followed up to four time points during adolescence. Breastfeeding duration was prospectively quantified using questionnaires during early childhood. Cardiometabolic risk factors, body composition, and weight-related biomarkers were assessed as outcomes during adolescent follow-up visits. Sex-stratified linear mixed-effects models were used to model the association between quartiles of breastfeeding duration and outcomes, adjusting for age and additional covariates.

RESULTS

Median breastfeeding duration was 7 months (minimum = 0, maximum = 36). Boys in the second quartile (median breastfeeding = 5 months) had lower total fat mass % (β (SE) -3.2 (1.5) P = .037), and higher lean mass % (3.1 (1.6) P = .049) and skeletal muscle mass % (1.8 (0.8) P = .031) compared with the reference group (median breastfeeding = 2 months). A positive linear trend between breastfeeding duration and trunk lean mass % (0.1 (0.04) P = .035) was found among girls. No association was found with other cardiometabolic indicators.

CONCLUSION

Despite sex-specific associations of breastfeeding duration with body composition, there was a lack of substantial evidence for the protective effects of breastfeeding against impaired cardiometabolic health during adolescence among Mexican youth. Further longitudinal studies with a robust assessment of breastfeeding are recommended.

Office blood pressure versus ambulatory blood pressure measurement in childhood obesity

BACKGROUND

The prevalence of obesity-related co-morbidities is rising parallel to the childhood obesity epidemic. High blood pressure (BP), as one of these co-morbidities, is detected nowadays at increasingly younger ages. The diagnosis of elevated BP and hypertension, especially in the childhood population, presents a challenge to clinicians. The added value of ambulatory blood pressure measurement (ABPM) in relation to office blood pressure (OBP) measurements in obese children is unclear. Furthermore, it is unknown how many overweight and obese children have an abnormal ABPM pattern. In this study we evaluated ABPM patterns in a population of overweight and obese children and adolescents, and compared these patterns with regular OBP measurements.

METHODS

In this cross-sectional study in overweight or obese children and adolescents aged 4-17 years who were referred to secondary pediatric obesity care in a large general hospital in The Netherlands, OBP was measured during a regular outpatient clinic visit. Additionally, all participants underwent a 24-hour ABPM on a regular week-day. Outcome measures were OBP, mean ambulatory SBP and DBP, BP load (percentage of readings above the ambulatory 95th blood pressure percentiles), ambulatory BP pattern (normal BP, white-coat hypertension, elevated BP, masked hypertension, ambulatory hypertension), and BP dipping.

RESULTS

We included 82 children aged 4-17 years. They had a mean BMI Z-score of 3.3 (standard deviation 0.6). Using ABPM, 54.9% of the children were normotensive (95% confidence interval 44.1-65.2), 26.8% had elevated BP, 9.8% ambulatory hypertension, 3.7% masked hypertension, and 4.9% white-coat hypertension. An isolated night-time BP load > 25% was detected in almost a quarter of the children. 40% of the participants lacked physiologic nocturnal systolic BP dipping. In the group of children with normal OBP, 22.2% turned out to have either elevated BP or masked hypertension on ABPM.

CONCLUSIONS

In this study a high prevalence of abnormal ABPM patterns in overweight or obese children and adolescents was detected. Additionally, OBP poorly correlated with the child's actual ABPM pattern. Herewith, we emphasized the usefulness of ABPM as an important diagnostic tool in this population.

DNA Methylation Is a Potential Biomarker for Cardiometabolic Health in Mexican Children and Adolescents

DNA methylation (DNAm) is a plausible mechanism underlying cardiometabolic abnormalities, but evidence is limited among youth. This analysis included 410 offspring of the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) birth cohort followed up to two time points in late childhood/adolescence. At Time 1, DNAm was quantified in blood leukocytes at long interspersed nuclear elements (LINE-1), H19, and 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD-2), and at Time 2 in peroxisome proliferator-activated receptor alpha (PPAR-α). At each time point, cardiometabolic risk factors were assessed including lipid profiles, glucose, blood pressure, and anthropometry. Linear mixed effects models were used for LINE-1, H19, and 11β-HSD-2 to account for the repeated-measure outcomes. Linear regression models were conducted for the cross-sectional association between PPAR-α with the outcomes. DNAm at LINE-1 was associated with log glucose at site 1 [β = -0.029, p = 0.0006] and with log high-density lipoprotein cholesterol at site 3 [β = 0.063, p = 0.0072]. 11β-HSD-2 DNAm at site 4 was associated with log glucose (β = -0.018, p = 0.0018). DNAm at LINE-1 and 11β-HSD-2 was associated with few cardiometabolic risk factors among youth in a locus-specific manner. These findings underscore the potential for epigenetic biomarkers to increase our understanding of cardiometabolic risk earlier in life.

Triglyceride-to-glucose index to detect a non-dipping circadian pattern in newly diagnosed hypertensive patients

Introduction: In this investigation, we aimed to explore the relationship between the triglyceride-glucose (TyG) index and the non-dipping blood pressure (BP) pattern in newly diagnosed hypertensive patients. Methods: In this retrospective study, 216 consecutive newly diagnosed hypertensive patients who had undergone 24-hour ambulatory blood pressure (ABPM) monitoring and had not received anti-hypertensive drugs were included. Non-dipping status was evaluated by a 24-h ABPM monitoring in all patients. We categorized the patients into two groups as; dippers (n=104 cases) and non-dippers (n=112 cases). The TyG index was derived from the fasting triglyceride and fasting glucose levels using the formula; ln[fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. Results: Non-dipper group had a higher TyG index than the dipper group. The TyG was an independent predictor of non-dipping BP in hypertensive individuals, according to multivariable analysis. The TyG index was negatively associated with a decrease in both systolic and diastolic BP during the nighttime. The ideal cutoff value of the TyG index in detecting non-dipping status was≥9.01 with 74.1% sensitivity and 71.2% specificity. A ROC comparison indicated that the area under the curve value of TyG index was superior to fasting triglyceride, fasting glucose, and homeostasis model assessment of IR (HOMA-IR) in detecting non-dipping BP. Conclusion: The TyG index was an independent predictor of non-dipping status in newly diagnosed hypertensive patients who had undergone 24-hour ABPM monitoring and had not received anti-hypertensive drugs. As a simple and easily obtained parameter, the TyG index can be used to detect such pattern among these patients.

Prognostic significance of reverse dipping status on lower limb event in type 2 diabetic patients without peripheral arterial disease

AIMS

We assessed reverse dipping influence on the risk of lower limb events in type 2 diabetic patients without peripheral arterial disease.

METHODS

Patients with type 2 diabetes addressed for cardiovascular risk stratification in our university hospital from 2008 to 2012 underwent 24 h blood pressure monitoring. Patients with a prior history of limb revascularization or with a stenosis > 50% of the legs were excluded. Reverse dipping was defined as a greater night-versus day-time systolic blood pressure. The endpoint was the first occurrence of lower limb revascularization or limb amputation. Hazard ratios (HRs) and 95% confidence intervals were calculated using the Cox model.

RESULTS

Two hundred and eighty-one patients were included. During a median follow-up of 9.4 [7.7-10.6] years, 20 lower limb events and 45 all-cause deaths were observed. Thirty-five patients were reverse dippers. The reverse dipping status was associated with lower limb events when considering all-cause death as a competitive risk, (HR 3.61 [1.16-11.2], P = 0.026). Reverse dipping, HbA1C and proteinuria were independently associated with lower limb outcome in a multivariable analysis (respectively HR 4.09 [1.29-12.9], P = 0.017, HR 1.30 [1.04-1.63], P = 0.022 and HR 1.06 [1.02-1.11], P = 0.001).

CONCLUSIONS

Reverse dipping status is independently associated with worse limb outcome in type 2 diabetic patients.

Hypertension in obese children is associated with vitamin D deficiency and serotonin dysregulation

Background

Obesity and hypertension represent serious health issues affecting the pediatric population with increasing prevalence. Hypovitaminosis D has been suggested to be associated with arterial hypertension. Serotonin by modulating nitric oxide synthase affect blood pressure regulation. The biological mechanism by which vitamin D specifically regulates serotonin synthesis was recently described. The aim of this paper is to determine the associations between vitamin D, serotonin, and blood pressure in obese children.

Methods

One hundred and seventy-one children were enrolled in the prospective cross-sectional study. Two groups of children divided according to body mass index status to obese (BMI ≥95th percentile; n = 120) and non-obese (n = 51) were set. All children underwent office and ambulatory blood pressure monitoring and biochemical analysis of vitamin D and serotonin. Data on fasting glucose, insulin, HOMA, uric acid, and complete lipid profile were obtained in obese children.

Results

Hypertension was found only in the group of obese children. Compared to the control group, obese children had lower vitamin D and serotonin, especially in winter. The vitamin D seasonality and BMI-SDS were shown as the most significant predictors of systolic blood pressure changes, while diastolic blood pressure was predicted mostly by insulin and serotonin. The presence of hypertension and high-normal blood pressure in obese children was most significantly affected by vitamin D deficiency and increased BMI-SDS.

Conclusions

Dysregulation of vitamin D and serotonin can pose a risk of the onset and development of hypertension in obese children; therefore, their optimization together with reducing body weight may improve the long-term cardiovascular health of these children.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03337-8.

The relationship between body fat ratio and blood pressure in school-age children

Hypertension (HTN) and obesity prevalences are rising in childhood and it is important to evaluate associations of these situations. The objective of this study is to investigate the relationship between HTN and body fat ratios (BFR) in children. This cross-sectional study was conducted among 134 participants who were directed to pediatric nephrology outpatient clinic with the prediagnosis of primary HTN. Weight, height, body fat ratio, blood pressure, and ambulatory blood pressure monitor (ABPM) was carried out for all the participants. Of the participants, 70 of them were diagnosed as hypertension with ABPM and included in the patient group, 64 of them had elevated office blood pressure (BP) but normotensive according to ABPM were included in the control group. Body fat ratio (BFR) levels of the patient group were higher than the control group (p < 0.05). There were significant linear correlation between night systolic blood pressure (SBP), night diastolic blood pressure (DBP), night mean arterial pressure (MAP), and BFR in the patient group (p < 0.05). There was a negative correlation between BFR and dipper (p = 0.022; p < 0.05) in the patient group. There was no correlation between BFR and blood pressures or dipper in the control group. According to our results BFR levels have significant association with HTN. According to our findings high BFR especially effects night BP, pulses, nondipping, and nighttime values can be evaluated only with ABPM. For prevention of HTN in children, caution should be given to monitor and lower BFR values.

Are there any new reliable markers to detect renal injury in obese children?

AIM

The aim of this study was to examine the serum and urine levels of kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), osteopontin (OPN), matrix metalloproteinase-9 (MMP-9), and serum Cystatin-C to determine the renal effect of obesity in obese children.

METHODS

Seventy-two obese and 35 non-obese healthy children were included in this study. Blood pressure (BP) was evaluated with office measurement. Creatinine, cystatin C, lipids, fasting glucose, and insulin levels were measured, and homeostasis model assessment -insulin resistance (HOMA-IR) was calculated. The urine albumin/creatinine ratio was calculated. The serum and urine KIM-1, NGAL, OPN, and MMP-9 levels were measured.

RESULTS

Serum cystatin-C, triglyceride, and homeostasis model assessment-insulin resistance (HOMA-IR) index were found to be significantly higher in the obese group (p = .0001), and high-density lipoprotein (HDL) cholesterol was found to be significantly lower (p = .019) in the obese group. No significant differences were found in serum KIM-1, NGAL, OPN or MMP-9 levels between groups (p > .05). No significant differences were found in urine KIM-1 and MMP-9 levels (p > .05), Urine NGAL, and OPN levels were found significantly higher in obese groups (p < .05).

CONCLUSIONS

According to our results, although serum KIM-1, NGAL, OPN, MMP-9, and urine MMP-9, urine KIM-1 do not appear to be ideal markers to evaluate renal injury in the early period of obesity, the serum levels of cystatin C and urine NGAL, urine OPN can be used as a good marker for assessing the renal effect of obesity which can lead end stage renal disease in pediatric population.

Novel Insights in the Metabolic Syndrome in Childhood and Adolescence

Metabolic syndrome (MetS) is recognized as an escalating major health risk in adults as well as in children and adolescents. Its prevalence ranges from 6 to 39% depending on the applied definition criteria. To date, there is no consensus on a MetS definition for children and adolescents. However, most authors agree on essential components such as glucose intolerance, central obesity, hypertension, and dyslipidemia; each representing a risk for cardiovascular disease. Recently, associations between MetS and non-alcoholic fatty liver disease, hyperuricemia, and sleep disturbances have emerged. Biomarkers like adipocytokines are a subject of current research as they are implicated in the pathogenesis of the MetS. Epigenetics and gestational programming, especially the role of microRNA, comprise a novel, rapidly developing and promising research focus on the topic of MetS. MicroRNAs are increasingly valued for potential roles in the diagnosis, stratification, and therapeutics of MetS. Early detection of risk factors, screening for metabolic disturbances, and the identification of new therapies are major aims to reduce morbidity and mortality related to MetS. Dietary modification and physical activity are currently the only adopted treatment approaches. Pharmacological therapies and bariatric surgery are still contradictory and, therefore, are only recommended in selected high-risk cases.

Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents

These pediatric hypertension guidelines are an update to the 2004 "Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents." Significant changes in these guidelines include (1) the replacement of the term "prehypertension" with the term "elevated blood pressure," (2) new normative pediatric blood pressure (BP) tables based on normal-weight children, (3) a simplified screening table for identifying BPs needing further evaluation, (4) a simplified BP classification in adolescents ≥13 years of age that aligns with the forthcoming American Heart Association and American College of Cardiology adult BP guidelines, (5) a more limited recommendation to perform screening BP measurements only at preventive care visits, (6) streamlined recommendations on the initial evaluation and management of abnormal BPs, (7) an expanded role for ambulatory BP monitoring in the diagnosis and management of pediatric hypertension, and (8) revised recommendations on when to perform echocardiography in the evaluation of newly diagnosed hypertensive pediatric patients (generally only before medication initiation), along with a revised definition of left ventricular hypertrophy. These guidelines include 30 Key Action Statements and 27 additional recommendations derived from a comprehensive review of almost 15 000 published articles between January 2004 and July 2016. Each Key Action Statement includes level of evidence, benefit-harm relationship, and strength of recommendation. This clinical practice guideline, endorsed by the American Heart Association, is intended to foster a patient- and family-centered approach to care, reduce unnecessary and costly medical interventions, improve patient diagnoses and outcomes, support implementation, and provide direction for future research.

Plasma from pre-pubertal obese children impairs insulin stimulated Nitric Oxide (NO) bioavailability in endothelial cells: Role of ER stress

Childhood obesity is commonly associated with early signs of endothelial dysfunction, characterized by impairment of insulin signaling and vascular Nitric Oxide (NO) availability. However, the underlying mechanisms remain to be established. Hence, we tested the hypothesis that endothelial insulin-stimulated NO production and availability was impaired and related to Endoplasmic Reticulum (ER) in human umbilical vein endothelial cells (HUVECs) cultured with plasma obtained from pre-pubertal obese (OB) children. OB children (N = 28, age: 8.8 ± 2.2; BMI z-score: 2.15 ± 0.39) showed impaired fasting glucose, insulin and HOMA-IR than normal weight children (CTRL; N = 28, age: 8.8 ± 1.7; BMI z-score: 0.17 ± 0.96). The in vitro experiments showed that OB-plasma significantly impaired endothelial insulin-stimulated NO production and bioavailability compared to CTRL-plasma. In parallel, in HUVECs OB-plasma increased GRP78 and activated PERK, eIF2α, IkBα and ATF6 (all ER stress markers). Moreover, OB-plasma increased NF-κB activation and its nuclear translocation. Notably, all these effects proved to be significantly restored by using PBA and TUDCA, known ER stress inhibitors. Our study demonstrate for the first time that plasma from obese children is able to induce in vitro endothelial insulin resistance, which is characterized by reduced insulin-stimulated NO production and bioavailability, endothelial ER stress and increased NF-κB activation.

Blood pressure from childhood to adolescence in obese youths in relation to insulin resistance and asymmetric dimethylarginine

BACKGROUND AND PROPOSE

Hypertension is the most important cardiovascular complication of obesity, even during childhood. Several studies have demonstrated that there is a natural progression of hypertension from childhood to adulthood. However, there are no data reporting a potential worsening in blood pressure (BP) already moving from the pre-pubertal to the pubertal period in obese youths. The aim of this study was to evaluate early change in BP and its relation to insulin resistance (IR) and asymmetric dimethylarginine (ADMA).

METHODS

Thirty obese children underwent a first assessment when they were pre-pubertal (visit_1) and were re-evaluated after a mean of 4.5 years (visit_2). At both visits, anthropometric parameters were assessed, blood samples were collected for measurement of insulin, glucose and ADMA and a 24-h ambulatory BP monitoring was performed.

RESULTS

At visit_2, the study participants presented increased HOMA-IR and ADMA compared to visit_1 (HOMA-IR: 3.6 ± 2.8 vs 2.8 ± 1.4, p = 0.01; ADMA: 1.57 ± 0.78 vs 0.77 ± 0.52 μmol/l, p < 0.001). Values of 24-h systolic and diastolic BP SDS (0.86 ± 0.79 vs 0.42 ± 0.83, p = 0.001; -0.45 ± 0.82 vs 0.08 ± 0.51, p = 0.001) were significantly increased at visit_2 compared to visit_1. At both visits, BMI-SDS, HOMA-IR and ADMA were associated with 24-h BP. In addition, over-time changes in IR and ADMA influenced changes in systolic blood pressure and diastolic blood pressure from childhood to adolescence (p < 0.05).

CONCLUSIONS

Changes in BP already occur moving from the pre-pubertal to the pubertal period in obese children, and modifications in insulin resistance and ADMA seem to be implicated in this early progression in BP.

Longitudinal Assessment of Blood Pressure in School-Aged Children: A 3-Year Follow-Up Study

The purpose of this study was to assess the prevalence of abnormal blood pressure in a population of school children during a 3-year follow-up period and its relationship with obesity. Anthropometric and blood pressure data were collected from a population of Italian school children during three consecutive years. During each year blood pressure measurements were repeated three times, at intervals of 1 week. A total of 564 school-children [311 boys; mean (SD) age 8.8 ± 1.4 years] were recruited. During each year, systolic and diastolic blood pressure decreased from visit 1 to visit 3 (p < 0.001). This was associated with a decline in the percentage of prehypertension/hypertension from visit 1 to visit 3. An abnormal blood pressure value in at least one study visit was found in 8.8-17 % of children, whereas the prevalence of hypertension at all three study visits was between 5.2 and 7.8 %, and that of prehypertension at all three visits was between 2.8 and 3.8 %. High blood pressure was more frequent in obese children. In this population of school children the percentage of prehypertension/hypertension remarkably varied when based on one versus three annual assessments, thus emphasizing the importance of repeated measurement before making a diagnosis of abnormal blood pressure. Adiposity was confirmed to be a determinant of high blood pressure.

Association of myeloperoxidase levels with cardiometabolic factors and renal function in prepubertal children

INTRODUCTION

Myeloperoxidase (MPO), an enzyme linking obesity and cardiovascular (CV) risk in adults, has rarely been studied in young children and no studies assessed its association with renal function. We sought to explore a possible association between serum MPO levels, obesity, CV risk factors and renal function in prepubertal children.

MATERIALS/METHODS

Cross-sectional evaluation of 309 children aged 8-9 years (161 normal weight, 148 overweight/obese), members of the birth cohort Generation I (Portugal). Anthropometrics (body mass index (BMI), waist-to-height ratio (WHtR) and % body fat mass (%BFM) by bioelectrical impedance analysis), 24-h ambulatory blood pressure monitoring and pulse wave velocity (PWV) were measured. Insulin resistance was estimated by the HOMA index (considering serum fasting glucose and insulin determinations). Serum MPO levels were assessed by immunoenzymatic assay.

RESULTS

MPO levels were positively associated with obesity indices (BMI z-score, WHtR and %BFM). Higher MPO levels were associated with higher 24-h and night-time mean arterial pressure, with nondipping and with higher values of insulin resistance. In normal weight children, the endothelial function, as evaluated indirectly by PWV, was an independent predictor of MPO levels. In overweight/obese children, estimated glomerular filtration rate increased significantly across tertiles of MPO (Ptrend = 0·031) and this association held after adjustment for age, sex, neutrophil and monocyte counts and CV risk factors.

CONCLUSIONS

Our results reinforce the role of MPO as a risk marker in obesity and related CV morbidities in young children. MPO levels associate with the dipping pattern and PWV and, among overweight/obese children, an association exists between MPO and renal function.

Increased left atrial size in obese children and its association with insulin resistance: a pilot study

Subclinical cardiac abnormalities represent predisposing factors for cardiovascular disease (CVD) in obese subjects. The aim of this study was to evaluate early cardiac abnormalities in obese youth and the potential association with insulin resistance (IR). Thirty obese (12 males (M)/18 females (F); age = 11.5 ± 2.4 years; body mass index (BMI)-standard deviation score (SDS) = +2.1 ± 0.5) and 15 normal weight (10 M/5 F; age = 12.8 ± 3.1 years; BMI-SDS = +0.3 ± 0.9) children and adolescents underwent Doppler two-dimensional echocardiographic assessments of left atrial (LA) and ventricular (LV) geometry and LV diastolic function (peak early [E] and late waves, E wave deceleration time, myocardial flow velocities). Homeostasis model assessment of IR (HOMA-IR) was used as an IR index. LA size was increased in obese children, as indicated by higher LA diameter (4.9 ± 0.5 vs 4.1 ± 0.4 cm, p < 0.001), area (14.3 ± 2.5 vs 10.7 ± 2.0 cm(2), p < 0.001), and volume (33.8 ± 10.6 vs 23.7 ± 6.4 ml, p = 0.003). LV mass was also increased in obese children (87.0 ± 16.6 vs 68.8 ± 13.2 g, p = 0.003), who also showed subtle diastolic dysfunctions, as indicated by higher values of E (97.1 ± 14.3 vs 86.2 ± 11.9 cm/s, p = 0.02). All the above parameters were significantly associated with BMI-SDS (p < 0.05). In addition, HOMA-IR was independently associated with LA diameter, area, and volume (β = 0.314, p = 0.040; β = 0.415, p = 0.008; β = 0.535, p = 0.001).

CONCLUSION

Obese children feature increased LA size, which emerged to be mainly correlated to, and possibly driven by IR, suggesting an increased CVD risk.

WHAT IS KNOWN

Left atrial and ventricular alterations have been reported in obese adults, and they represent predisposing factors for cardiovascular disease. There is some evidence suggesting that obese children show increased left ventricular mass and also increased atrial size, although with conflicting results.

WHAT IS NEW

Obese normotensive children showed a moderately increased atrial size, subtle alterations in left cardiac diastolic function, and ventricular mass. An association between insulin resistance and left cardiac changes was found, although its mechanism remains to be determined.

High trait rumination is associated with blunted nighttime diastolic blood pressure dipping

Background

Blunted blood pressure (BP) dipping during nighttime sleep has been associated with an increased risk of cardiovascular events. Psychological traits have been associated with prolonged cardiovascular activation and a lack of cardiovascular recovery. This activation may extend into nighttime sleep and reduce BP dipping.

Purpose

This study aims to evaluate the association between trait rumination and nighttime BP dipping.

Methods

Sixty women scoring either high or low on trait rumination underwent one 24-h ambulatory BP monitoring session. Self-reported wake and sleep times were used to calculate nighttime BP.

Results

High trait rumination was associated with less diastolic blood pressure (DBP) dipping relative to low trait rumination. Awake ambulatory BP, asleep systolic blood pressure (SBP) and DBP, and asleep SBP dipping were not associated with trait rumination.

Conclusions

In a sample of young women, high trait rumination was associated with less DBP dipping, suggesting that it may be associated with prolonged cardiovascular activation that extends into nighttime sleep, blunting BP dipping.

Obese children and adolescents have elevated nighttime blood pressure independent of insulin resistance and arterial stiffness

BACKGROUND

Insulin resistance has been related to elevated blood pressure (BP) in obese children and may adversely affect the vasculature by arterial stiffening. The objective was to investigate whether daytime and nighttime BP were elevated and related to insulin resistance and arterial stiffness in obese children and adolescents.

METHODS

Ninety-two obese patients aged 10-18 years were compared with 49 healthy control individuals. Insulin resistance was measured as the homeostatic assessment model (HOMA), and arterial stiffness was measured as carotid-femoral pulse wave velocity (cfPWV).

RESULTS

Mean ± SD daytime systolic BP (SBP) (obese: 125±8.3mm Hg; control: 121±10.1mm Hg; P = 0.03) and nighttime SBP (obese: 108±10.7mm Hg; control: 102±8.2mm Hg; P = 0.0001) were higher in the obese group when compared with the control group. No difference was found in daytime diastolic BP (DBP), whereas nighttime DBP (obese: 60±6.6mm Hg; control: 57±4.8mm Hg; P = 0.001) and night-to-day BP ratios were higher in the obese group. Nighttime SBP was related to BMI z score (β = 6.0; 95% confidence interval (CI) = 2.9-9.1; P = 0.0002) and waist/height ratio (β = 36.7; 95% CI = 5.6-67.9; P = 0.02) in the obese group. HOMA index (obese: median = 3.7, interquartile range (IQR) = 2.3-6.0; control: median = 2.6, IQR = 1.8-3.4; P = 0.002) was higher, whereas cfPWV (obese: 4.8±0.8 m/s; control: 5.1±0.6 m/s; P = 0.03) was lower in the obese group. CfPWV was not related to logHOMA index. In multiple regression analyses, the higher nighttime BP in the obese group was independent of logHOMA and cfPWV.

CONCLUSIONS

Obese children had a higher nighttime BP when compared with the control group independently of insulin resistance and arterial stiffness. No relationship was found between insulin resistance and arterial stiffness. CLINICAL TRIAL REGISTRATION Clinicaltrials.gov identifier NCT01310088.

Is breastfeeding protective for blood pressure in schoolchildren? A cohort study in northeast Brazil

OBJECTIVE

This study assessed the influence of breastfeeding and nutritional status of full-term infants on blood pressure at school age.

SUBJECTS AND METHODS

This was a cross-sectional study nested in a cohort of 375 infants recruited at birth between 1993 and 1994 in the state of Pernambuco, Brazil. A sample of 213 8-year-old children had their blood pressure measured. A multivariate linear regression analysis was used to identify the influence of low birth weight and breastfeeding duration on blood pressure, adjusting for socioeconomic conditions, maternal nutritional status, eating habits, growth rate (0-6 months), and the children's anthropometry at 8 years.

RESULTS

Mean values of children's blood pressure were significantly higher with lower duration of breastfeeding. Higher per capita family income, maternal body mass index and height, child's weight and length at birth, and child anthropometric dimensions at 8 years of age were associated with higher levels of blood pressure. The multivariate linear regression analysis showed that children who were breastfed for less than 40 days had higher systolic blood pressures, explaining 2.2% of its variation. Anthropometry at 8 years of age explained the higher variance in systolic blood pressure (12.6%) with emphasis on waist circumference (9.5%), followed by per capita income (3.2%) and maternal height (2.1%). Birth weight and length had no influence on blood pressure levels in this age group.

CONCLUSIONS

Children's waist circumference, duration of breastfeeding, socioeconomic conditions, and maternal nutritional status influenced blood pressure levels of schoolchildren born full term, rather than low birth weight.

Nocturnal blood pressure non-dipping is prevalent in severely obese, prepubertal and early pubertal children

AIM

To investigate the prevalence of nocturnal blood pressure dipping among obese prepubertal and early pubertal children and to analyse the relationship between dipping and measures of insulin-glucose metabolism or sleep-disordered breathing.

METHODS

We studied 76 obese children (41% girls) under clinical care, with an average age of 10.4 ± 1.7 and a body mass index Z-score (BMI Z-score) of 6.2 ± 1.6. We performed a 24-h ambulatory blood pressure measurement. Non-dipping was defined as a nocturnal blood pressure reduction of <10%. We calculated measures of insulin-glucose metabolism from the performed frequently sampled intravenous glucose-tolerance test and from fasting blood samples. Overnight sleep polygraph recordings were performed to assess sleep-disordered breathing.

RESULTS

Forty-two percent of the children were systolic non-dippers, and 17% were diastolic non-dippers. There were no associations between systolic or diastolic dipping and measures of insulin-glucose metabolism after adjustments for BMI Z-score, gender and pubertal status. There were no associations between dipping and measures of sleep-disordered breathing.

CONCLUSION

Nocturnal non-dipping was two times higher among severely obese, prepubertal and early pubertal children, compared to previous reports among children in general. There were no associations between nocturnal dipping and insulin-glucose metabolism or measures of sleep-disordered breathing in this group.

Metabolic syndrome in youth: chimera or useful concept?

Metabolic syndrome (MetS) is a cluster of cardiometabolic risk factors associated with an increased risk for the development of cardiovascular diseases and type 2 diabetes. The prevalence of the MetS is not particularly high in the overall pediatric population (3 %-4 %) but it is as high as 30 %-50 % among overweight youth. Several definitions of the MetS have been used, thus, generating confusion and difficulties in defining the true prevalence of this syndrome. The recent definition of the International Diabetes Federation has tried to standardize the diagnostic criteria. However, there are still some concerns about use of cut-offs values and dichotomous variables, and some debate as to whether a continuous cardiometabolic risk score could be more appropriate for the pediatric population. Although there are some studies that have shown the association between childhood and adolescent MetS with long-term outcomes, further prospective studies are needed to clarify the true value of diagnosing MetS in youth.

Nocturnal hypertension and organ damage in dippers and nondippers

BACKGROUND

The relationship between high nocturnal blood pressure (BP), organ damage and the dipping/nondipping status is poorly defined. We investigated whether a consistent dipping/nondipping pattern defined on the basis of two 24-h ambulatory BP monitorings (ABPMs) is associated with subclinical organ damage in untreated hypertensive patients with elevated nighttime BP.

METHODS

All subjects underwent the following procedures: cardiac and carotid ultrasonography, 24-h urine collection for microalbuminuria (MA), and ABPM over two 24-h periods within 4 weeks. Nocturnal hypertension was defined according to current guidelines (i.e., nighttime systolic BP (SBP) ≥120 and/or diastolic BP ≥70 mm Hg) and nondipping status as an average reduction in SBP at night <10% compared with day-time values.

RESULTS

Among 343 subjects, 199 were dippers and 144 nondippers. No differences were found in clinical variables, average 48-h BP, left ventricular mass, carotid intima-media (IM) and urinary albumin excretion between the groups. This was also the case for prevalence rates of left ventricular hypertrophy, carotid IM thickening or plaque and MA. Finally, no relationship was found between the markers of organ damage and BP fall at night.

CONCLUSIONS

In the presence of nocturnal hypertension, dippers have a similar subclinical cardiac and extra-cardiac organ damage as their nondipper counterparts. These data suggest that therapeutic strategies only addressing the nondipper pattern may be insufficient to protect hypertensive subjects against the dangerous effects of elevated nocturnal BP.American Journal of Hypertension, (2012); doi:10.1038/ajh.2012.49.

Pediatric ambulatory blood pressure monitoring: indications and interpretations

The prevalence of hypertension in children and adolescents is increasing, especially in obese and ethnic children. The adverse long-term effects of hypertension beginning in youth are known; therefore, it is important to identify young patients who need intervention. Unfortunately, measuring blood pressure (BP) is difficult due to the variety of techniques available and innate biologic variation in BP levels. Ambulatory BP monitoring may overcome some of the challenges clinicians face when attempting to categorize a young patient's BP levels. In this article, the authors review the use of ambulatory BP monitoring in pediatrics, discuss interpretation of ambulatory BP monitoring, and discuss gaps in knowledge in usage of this technique in the management of pediatric hypertension.

Implications for kidney disease in obese children and adolescents

Increasing attention has been focused on the implications of obesity in adults on the development of kidney disease, but data on the obese pediatric population are lacking. The aim of this study was to investigate whether changes in various renal function indexes/markers, as expressed by the glomerular filtration rate [GFR, as estimated by the Schwartz formula (eGFR)], serum cystatin C (CysC) level, albumin excretion rate (AER), and modifications in nitric oxide (NO; an important modulator of renal function and morphology), urinary isoprostanes (markers of oxidative stress), and blood pressure (BP), can be detected in obese children and adolescents when compared to normal weight controls. Blood and urinary samples were collected to evaluate markers of renal function, serum and urinary NO, and urinary isoprostanes in 107 obese Caucasian subjects and 50 controls. Ambulatory BP monitoring (ABPM) was performed in all cases. Obesity was expressed by the body mass index standard deviation score (SDS-BMI), and insulin resistance by the homeostasis model assessment of insulin resistance (HOMA-IR). CysC and eGFR did not significantly differ between the two groups; AER was increased in obese children. CysC and GFR were related to HOMA-IR, and AER was related to HOMA-IR and SDS-BMI. Obese subjects had reduced NO levels and increased urinary isoprostanes and BP measurements; all three parameters were related to SDS-BMI and insulin resistance. ABPM showed an increased incidence of hypertension and non-dipping in the obese group. Based on our comparison of obese and nonobese children, we conclude that renal involvement is not an early clinically evident manifestation of adiposity in childhood, since no overt changes in eGFR and only a mild albuminuria were detected. A longer exposure to obesity is probably needed before renal function impairment appears.

Long-term follow-up of cardiovascular risk factors after exercise training in obese children

OBJECTIVE

We previously demonstrated beneficial effects of physical activity on cardiovascular disease (CVD) risk factors, body mass index (BMI) and fat mass in pre-pubescent obese children. The aim of this study was to determine whether these changes were maintained 2 years later.

METHODS

Two years after the Randomised Controlled Trial, we performed a follow-up study with 20 of 38 subjects (11.4 ± 1.8 years). Outcomes included blood pressure (BP) by ambulatory monitoring; arterial function and structure using high-resolution ultrasound, BMI, body composition by dual-energy x-ray absorptiometry (DXA), physical activity using accelerometer, and biological markers.

RESULTS

During the 2-year follow-up period, mean 24-hour diastolic BP z-score significantly decreased (1.4 ± 1.2 vs. 0.3 ± 1.4, p = 0.04), while systolic BP z-score was slightly reduced (2.4 ± 1.5 vs. 1.4 ± 1.7, p = 0.067). Blood pressure changes were greater in children who diminished their BMI z-score compared with the ones who did not. Systolic hypertension rates dropped from 50 to 28% and diastolic hypertension from 42 to 6%. In addition, arterial intima-media thickness (0.51 ± 0.03 vs. 0.51 ± 0.06, p = 0.79), BMI z-score (2.9 ± 0.8 vs. 2.9 ± 1.1 kg.cm(-2), p = 0.27), body fat (41.9 ± 6.9 vs. 42.8 ± 6.7%; p = 0.39) and physical activity count (703 ± 209 vs. 574 ± 244 cpm, p = 0.30) were stable.

CONCLUSION

To our knowledge, this is the first study reporting that beneficial effects on adiposity and CVD risk factors of a physical activity centred intervention are sustained 2 years after the cessation of training in obese children. Subjects stabilized BMI z-score and maintained physical activity with further improvement of BP and stabilization of arterial wall remodelling. We conclude that it is important to encourage physical activity in this population. Effects of Aerobic Exercise Training on Arterial Function and Insulin Resistance Syndrome in Obese Children: A Randomised Controlled Trial: NCT00801645.

Influência do índice de massa corporal e da circunferência abdominal na pressão arterial sistêmica de crianças

OBJETIVO: Avaliar os níveis pressóricos em crianças e relacioná-los ao índice de massa corporal e à circunferência abdominal. MÉTODOS: Por meio de estudo prospectivo e transversal, avaliaram-se 1.408 escolares com idade entre cinco anos e dez anos e 11 meses, matriculados em escolas públicas do Município de Santo André. Foram coletados: peso ao nascer; peso e estatura, expressos como escore Z do índice de massa corporal (ZIMC) e estatura para idade (ZEI). A pressão arterial (medida única) foi aferida pelo mesmo examinador. Considerou-se: desnutrição quando ZIMC<-2, obesidade ZIMC>+2, baixa estatura se ZEI<-2; circunferência abdominal aumentada (ponto de corte >P90 para sexo e idade) e pressão arterial elevada quando superior ao percentil 90 para sexo, idade e estatura. A análise estatística incluiu o teste do qui-quadrado e o cálculo da Odds Ratio, adotando-se como significante o valor de p<0,05. RESULTADOS: A mediana de idade foi de sete anos, sendo 51% do sexo feminino. Níveis elevados foram encontrados em 19 e 12% dos escolares para a pressão arterial sistólica e diastólica, respectivamente. Verificaram-se: baixa estatura, desnutrição, obesidade e aumento da circunferência abdominal em 2,6%, 3,1%, 7,3% e 13,4% da amostra, respectivamente. A presença de obesidade foi o fator mais fortemente associado ao aumento de pressão arterial sistólica (OR 2,1; IC95% 1,3-3,3; p<0,001) e diastólica (OR 2,6; IC95% 1,6-4,3; p<0,001). A circunferência abdominal também se associou com pressão arterial sistólica elevada (OR 1,6; IC95% 1,0-2,5; p=0,027). CONCLUSÕES: A pressão arterial sistêmica elevada em crianças associa-se à obesidade e ao aumento da circunferência abdominal.

Elevated ambulatory blood pressure in a multi-ethnic population of obese children and adolescents

OBJECTIVES

To evaluate the relationship among ambulatory blood pressure (ABP), body mass index (BMI), and homeostasis model assessment (HOMA) in a multi-ethnic population of obese children with clinic blood pressure in the reference range.

STUDY DESIGN

A total of 43 obese normotensive children (7-17 years old) were recruited. ABP monitoring, oral glucose tolerance test, lipid levels, and urine microalbumin levels were obtained.

RESULTS

Fourteen percent of the subjects had elevated 24-hour systolic blood pressure (SBP), 9.3% had elevated daytime SBP, and 32.6 % elevated nighttime SBP. For diastolic blood pressure, 4.7% of the sample had an elevated mean nighttime value. Children with more severe obesity (BMI SD score >2.5) had higher 24-hour and nighttime SBP than children with less severe obesity (BMI SD score < or =2.5). Children with HOMA values in the highest quartile had larger waist circumference and higher clinic blood pressure than children with HOMA values in the lowest quartile, and no difference in the mean ABP values was found in the 2 groups . Multiple linear regression analysis showed that 24-hour and nighttime SBP were significantly correlated with BMI SD score.

CONCLUSION

Obese children with normal clinic blood pressure often exhibit elevated ABP. The risk for ambulatory hypertension appears to be correlated with the degree of obesity.

The possible role of liver steatosis in defining metabolic syndrome in prepubertal children

Insulin resistance is a key component of the metabolic syndrome (MS) and is strongly associated with liver steatosis. Our aim was to evaluate whether MS should be diagnosed already in obese prepubertal children and whether its prevalence is influenced by the inclusion of hepatic steatosis as a diagnostic criterion. Eighty-nine obese children (43 boys; age median [range], 8.5 [6-10] years) were enrolled. Metabolic syndrome was diagnosed according to a classic definition: presence of 3 or more of the following criteria-body mass index greater than 2 standard deviation score, triglycerides greater than the 95th percentile, high-density lipoprotein cholesterol less than the fifth percentile, blood pressure greater than the 95th percentile, and impaired glucose tolerance. Afterward, liver steatosis was included as an additional criterion to this definition. Metabolic syndrome was diagnosed in 12 children (13.5%) according to the first definition and in 18 children (20.2%) when liver steatosis was included. The prevalence of MS increased across homeostasis model assessment of insulin resistance tertiles (P for trend = .01). The prevalence of the single components of the MS was as follows: obesity, 100%; hypertriglyceridemia, 27%; low high-density lipoprotein cholesterol, 2.2%; hypertension, 34.8%; impaired glucose tolerance, 4.5%; and nonalcoholic fatty liver disease, 21.3%. In conclusion, MS is common already among prepubertal obese children, particularly when liver steatosis is included among the diagnostic criteria. Therefore, screening for the MS should be performed in this age group; and hepatic steatosis should be considered as an additional diagnostic criterion.

Insulin resistance is a risk factor for high blood pressure regardless of body size and fat distribution in obese children

BACKGROUND AND AIM

The prevalence of children with hypertension is increasing, especially in obese children. This study was to assess the relationship between blood pressure, indexes of adiposity, body fat distribution and insulin resistance.

SAMPLE

1044 children (M/F: 484/560; aged 6-11 years). Anthropometry and blood pressure were measured and fasting blood samples were tested for triacylglycerol, total cholesterol, HDL cholesterol, glucose, insulin and ALT. The prevalence of high blood pressure in overweight males and females was 14.3 and 6.4%, respectively (chi(2)=16.73, p<0.001) and in obese it was 40.4 and 32.8%, respectively (chi(2)=5.56, p<0.001). High blood pressure increased progressively with BMI z-score categories (chi(2)=67.99, p<0.001) as well as with waist/height ratio (W/Hr) categories (chi(2)=23.51, p<0.001). Hypertensive subject had significantly higher insulin (15.6+/-9.8 vs 11.9+/-7.2, p<0.001 and 20.63+/-14.7 vs 15.26+/-9.8, p<0.001 in males and females respectively) and HOMA(IR) (3.23+/-2.1 vs 2.42+/-1.49, p<0.001 and 4.12+/-2.87 vs 3.07+/-1.98, p<0.001 in males and in females, respectively) than non-hypertensive ones. Among metabolic and cardiovascular risk factors, HOMA(IR) was the only variable able to predict high blood pressure in obese boys and girls, in addition to BMI or body fat distribution (waist, W/Hr). The highest HOMA(IR) category was the most important predicting factor of high blood pressure in overweight and obese children in addition to body size or body fat distribution.

CONCLUSIONS

Blood pressure is associated with the degree of overweight and the indices of body fat distribution. Insulin resistance is an independent additional risk factor for hypertension.

Altered cardiovascular rhythmicity in children with white coat and ambulatory hypertension

Adults with ambulatory hypertension or white coat hypertension (WCH) display abnormal cardiovascular rhythms. We studied cardiovascular rhythms by Fourier analysis of 24-h ambulatory blood pressure (BP) measurement profiles in 129 hypertensive children, 54 children with WCH, and 146 age-, height-, and gender-matched healthy subjects. The day/night mean arterial pressure ratio was lower in hypertensive and patients with WCH compared with controls (1.13 versus 1.16 versus 1.21, respectively; p < 0.0001). Eighty-five percent of controls were dippers compared with 74% of WCH (n.s.) and 64% of patients with ambulatory hypertension (p < 0.0001). The prevalence of 24-h rhythms was similar among the groups, but prevalence of 12-h BP rhythms was increased in hypertensive (67%) and WCH (72%) compared with controls (51%, p < 0.0001). The amplitudes of the 24-, 8-, and 6-h BP rhythms were reduced in hypertensive and WCH compared with controls (p < 0.05). Hypertensive and patients with WCH displayed delayed 24-, 12-, 8-, 6-h acrophases in comparison with controls (p < 0.05). In conclusion, hypertensive children exhibit abnormal cardiovascular rhythmicity compared with controls, especially a higher prevalence of nondipping compared with normotensive children. Abnormalities in patients with WCH are intermediate between healthy children and patients with ambulatory hypertension.

Insulin sensitivity in prepubertal Caucasian normal weight children

BACKGROUND

Determining whether or not a child is insulin resistant is becoming a matter of fundamental interest even in childhood, as the incidence of metabolic complications of insulin resistance is rising. Thus reference values are needed.

AIM

To set percentiles for HOMA-IR and WBISI in Caucasian normal weight prepubertal children.

POPULATION

238 normal weight prepubertal Caucasian children (126 males/112 females).

METHODS

After physical examination including anthropometric measurements all children underwent an oral glucose tolerance test from which HOMA-IR and WBISI were calculated.

RESULTS

HOMA-IR values above the 95th percentile (2.03) and WBISI values below the 5th percentile (5.67) represent the cut-off values for the determination of insulin resistance.

CONCLUSION

These reference values are useful to easily detect insulin resistance within the prepubertal Caucasian population representing a helpful tool for clinicians to target such children in order to improve insulin sensitivity.

Home and office blood pressure in children and adolescents: the role of obesity. The Arsakeion School Study

Obesity is related to office blood pressure (OBP). Important discrepancies exist between OBP and home blood pressure (HBP), providing complementary information for the management of hypertension. The association between obesity and HBP has not been investigated in children. The evidence on the role of obesity in the predominance of systolic blood pressure (SBP) over diastolic (DBP) in paediatric hypertension is limited. A total of 778 healthy subjects aged 6-18 years were recruited in this study. OBP and HBP were measured using electronic devices validated in children. Anthropometric measurements were measured and expressed as z-scores for height or age. Among all indices of obesity (z-scores), body mass index (BMI) showed the best association with BP. The effect of obesity (BMI) was more pronounced on: (i) SBP than DBP and (ii) H-SBP than O-SBP (O-SBP: r2=0.09, O-DBP: r2=0.05, H-SBP: r2=0.12, H-DBP: r2=0.06). The prevalence of systolic hypertension was higher than that of diastolic hypertension. This difference was significant only in office readings and independent from obesity (normal weight: 6.3% systolic hypertension versus 1.2% diastolic; obese: 37.9% versus 6.9%, P<0.05 for both). These data imply that in children and adolescents the z-score of BMI is the most appropriate index of the association between BP and obesity. It also suggests that obesity is probably more closely associated with home than office BP. Finally, although obesity appears to affect SBP more than DBP, these results suggest that the predominance of systolic hypertension in children and adolescents might not be only related to obesity but also to the measurement setting (office).

Insulin resistance and obesity in childhood

Childhood obesity is a significant health problem that has reached epidemic proportions around the world and is associated with several metabolic and cardiovascular complications. Insulin resistance is a common feature of childhood obesity and is considered to be an important link between adiposity and the associated risk of type 2 diabetes and cardiovascular disease. Insulin resistance is also a key component of the metabolic syndrome, and its prevalence in the paediatric population is increasing, particularly among obese children and adolescents. Several factors are implicated in the pathogenesis of obesity-related insulin resistance, such as increased free fatty acids and many hormones and cytokines released by adipose tissue. Valid and reliable methods are essential to assess the presence and the extent of insulin resistance, the associated risk factors and the effect of pharmacological and lifestyle interventions. The two most common tests to assess insulin resistance are the hyperinsulinemic euglycemic clamp and the frequently sampled i.v. glucose tolerance test utilizing the minimal model. However, both these tests are not easily accomplished, are time consuming, expensive and invasive. Simpler methods to assess insulin resistance based on surrogate markers derived from an oral glucose tolerance test or from fasting insulin and glucose levels have been validated in children and adolescents and widely used. Given the strong association between obesity, insulin resistance and the development of metabolic syndrome and cardiovascular disease, prevention and treatment of childhood obesity appear to be essential to prevent the development of insulin resistance and the associated complications.

Impaired endothelial and smooth muscle functions and arterial stiffness appear before puberty in obese children and are associated with elevated ambulatory blood pressure

AIMS

To determine whether impaired brachial endothelial (flow-mediated dilation, FMD) and smooth muscle function (nitroglycerin-mediated dilation, NTGMD), and remodelling of the common carotid artery (CCA) develop before puberty in obese children.

METHODS AND RESULTS

Arterial intima-media thickness (IMT), FMD and NTGMD were measured by high-resolution ultrasound in 48 obese and 23 lean pre-pubertal children (8.8 +/- 1.5 years old). We assessed central pulse pressure, incremental elastic modulus (Einc), casual and ambulatory systolic (SBP) and diastolic blood pressure (DBP), and body fatness by DXA. Obese children had significantly lower FMD (4.5 +/- 4.0 vs. 8.3 +/- 1.7%), NTGMD (19.0 +/- 9.0 vs. 25.8 +/- 6.1%), and increased Einc (13.9 +/- 5.2 vs. 10.4 +/- 5.2 mmHg/10(2)), ambulatory SBP (121.3 +/- 12.6 vs. 106.6 +/- 7.1, mmHg), and DBP (69.1 +/- 5.7 vs. 63.7 +/- 4.5) than lean subjects, whereas IMT was not augmented. Ambulatory systolic hypertension was present in 47% of obese subjects. FMD, NTGMD, and Einc were correlated with body fatness, body mass index, and blood pressure (BP).

CONCLUSION

Impaired endothelial and smooth muscle functions and altered wall material develop before puberty in obese children, however remodelling of the CCA is not yet present. Arterial dysfunction may be considered as the first marker of atherosclerosis and is associated with elevated BP. Ambulatory blood pressure monitoring may be a potential tool to improve risk stratification in obese children.