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Objective and Methods: The study aimed at evaluating, in a large sample of Italian children, the reclassification of blood pressure categories with the new U.S. nomograms, obtained in a population of normal-weight children (American Academy of Pediatrics Clinical Practice Guidelines, AAP-CPG), compared with the Fourth Report/European Society of Hypertension (ESH) nomograms. The performance of the two classifications in identifying the presence of left ventricular hypertrophy was also assessed., Results: In 951 individuals referred to a Pediatric Center for Cardiovascular Risk Prevention, a 12% increase in the prevalence of children with blood pressure at least 90th percentile was observed by using the new nomograms. In the subsample of children aged at least 13 years, the application of the blood pressure fixed cutoff values of 120/<80 mmHg (for 'elevated' blood pressure) and of 130/80 mmHg (for hypertension) led to a change in the blood pressure category (worse or better) in about 30% of cases as compared with the AAP-CPG classification based on percentiles. Regarding the identification of individuals with left ventricular hypertrophy, the AAP-CPG classification led to an increase in the true positive fraction (sensitivity) of 5.5%, and to an increment of the false-positive fraction (1 - specificity) of 5.8%. The logistic regression model, adjusted for possible confounding factors, and the ROC curves obtained from the linear predictor of the model showed an identical performance of the Fourth Report/ESH and the AAP-CPG classifications., Conclusion: In our paediatric population, the AAP-CPG classification slightly increased the prevalence of elevated blood pressure values compared with the Fourth Report/ESH classification. Moreover, the application of more 'physiological' nomograms, based on a population of normal-weight children, did not yield any advantage in identifying individuals with early cardiac organ damage.

Background: Children's excess weight is a common problem due to low-quality diet and poor physical activity and is a risk factor associated with hypertension. Aim of this study was to assess the effect of a nonpharmacological multidisciplinary intervention on blood pressure (BP) and body weight in a population of children with excess weight and/or elevated BP., Methods: Children consecutively referred to a Prevention of Cardiovascular Risk Clinic by the primary care pediatrician from 2009 to 2015 were assessed at baseline and followed up over time., Results: Out of 273 children (median age 11.4 years, 55% male), 61% were excess weight only, 7% had elevated BP only, and 32% showed both conditions. The probability of reaching the clinical target (normal weight and BP values) at 1 year of follow-up was 19% (confidence interval [CI]: 14%; 24%) and increased up to 38% (CI: 28%; 47%) at 3 years. At 1 year of follow-up, in the overall population both body mass index (BMI) and systolic BP z-scores decreased significantly from 1.77 to 1.47 and from 0.99 to 0.52, respectively (P < 0.0001). BP was significantly reduced in both children with elevated BP only (reduction = 0.91, P = 0.0157) and subjects with excess weight and elevated BP (reduction = 0.89, P < 0.0001). Variables significantly related with systolic BP z-score at 1 year of follow-up were baseline systolic BP z-score and BMI z-score reduction during follow-up (P < 0.001 and P = 0.0003, respectively)., Conclusion: Our data demonstrate the efficacy of lifestyles modification on weight and BP in children, both when elevated BP and excess weight were present as distinct clinical problems and in the case of their association.

Background: Hypertension and obesity in childhood are related to early cardiac damage, as left ventricular hypertrophy. Few studies have analyzed the independent effects of hypertension and weight excess on diastolic function and left ventricular geometry., Objective: We studied the effects of weight, waist circumference (as an index of fat distribution) and blood pressure on left ventricular mass index, the risk of left ventricular hypertrophy, diastolic function and left ventricular geometry in 526 children (237 girls, age range 6-15 years)., Methods: Children were divided into normotensive, prehypertensive and hypertensive (US Nomograms) groups, and into normal-weight, overweight, and obese (International Obesity Task Force classification) groups. Left ventricular mass index, diastolic function and left ventricular geometry were assessed., Results: SBP z-scores and blood pressure categories significantly influenced cardiac mass (P < 0.001 and P = 0.02, respectively) and the prevalence of left ventricular hypertrophy (P < 0.001 and P < 0.05, respectively). Obesity, BMI, and waist circumference z-scores were significantly associated with an increment in E/Em ratio (P < 0.001, P < 0.01, and P < 0.01, respectively). Increasing blood pressure values and the presence of prehypertension (P < 0.05) and hypertension (P < 0.003), but not weight excess, were associated with concentric cardiac remodeling. In contrast, concentric hypertrophy was associated with hypertension (P < 0.01), obesity (P < 0.001), and increasing waist circumference (P < 001)., Conclusions: Blood pressure values and hypertension are independently associated with an increase of cardiac mass and the presence of cardiac hypertrophy. Obesity and waist circumference, but not hypertension, are associated with a worsening of diastolic function, whereas only hypertensive children show high prevalence of concentric remodeling. Blood pressure and body weight and fat distribution have an independent and different impact on left ventricular structure and function in children.

Objectives: Hyperuricemia has been shown to be a strong correlate of hypertension in children. However, the complex interaction between serum uric acid (UA), systemic blood pressure (BP), and possibly confounding factors has been elucidated only in part., Methods: We evaluated office BP as well as clinical and biohumoral parameters in a cross-sectional cohort of 501 children (280 boys and 221 girls) aged between 6 and 18 years (mean = 10.8 years) consecutively referred for cardiovascular risk assessment., Results: Overall, 156 (31.1%) were normotensive, 122 (24.4%) showed transient hypertension, 87 (17.4%) had prehypertension, and 136 (27.1%) had hypertension. Altogether 33.3% and 40.5% of the study group were overweight or obese, respectively. There was a trend toward greater weight and waist circumference and higher BMI, Homeostasis Model Assessment index, and UA levels as the BP categories rose. Moreover, the prevalence of pubertal children, obesity, and waist-to-height ratio above 0.50 progressively increased from lower to upper BP categories. After adjusting for puberty, gender, BMI (z-score), Homeostasis Model Assessment index, and renal function, UA was found to be directly related to systolic and diastolic BP values (P = .03). Using normotensive children for comparison, the risk of showing prehypertension or hypertension increased by at least 50% for each 1 mg/dL UA increase (P < .01), whereas it doubled for children in the top gender-specific UA quartile (P < .03)., Conclusions: Increased UA levels showed an independent predictive power for the presence of higher BP levels among a cohort of children at relatively high cardiovascular risk.

Objective: Aim of the study was to assess the role of family history, physical activity and parental smoking in the prediction of BMI, SBP and hypertension risk in children., Participants and Methods: In a paediatric primary care setting, a sample of 1310 children aged 5-14 years was systematically selected by 48 family paediatricians in northern Italy. BMI, waist circumference-to-height ratio (WtHr), SBP and DBP were measured and the information on the presence of small birth weight for gestational age (SGA) and early adiposity rebound (EAR) was collected. Data concerning exercise, video time, family history for cardiovascular diseases and parental smoking were derived from parental interview. Data were collected using an 'ad hoc designed' electronic sheet available online., Results: Multiple linear regression showed that the presence of EAR, low exercise (<2 h/week), high video time (>2  h/day TV/videogames/computer) and parental smoking were associated to higher BMI (z-score; P < 0.005). Age, BMI (z-score), WtHr, presence of SGA, low exercise, high video time and family history of cardiovascular diseases were associated to SBP values (P < 0.03). Logistic regression analysis showed that factors related to risk of hypertension and prehypertension were BMI (z-score; odds ratio, OR 2.63; 95% confidence interval, CI 2.12-3.28), WtHr (OR 1.13; 95% CI 1.10-3.28) and low exercise (OR 1.58; 95% CI 1.12-2.24; P <0.01)., Conclusion: Our study demonstrates that a simple tool like a cardiovascular multi-item sheet can provide useful information to paediatricians for child health. Physical exercise plays a pivotal role in obesity prevention and protection from hypertension risk.

Objective: The aim of the present study was to evaluate whether insulin resistance [as measured by Homeostasis Model Assessment (HOMA) index] has an effect on prehypertension and hypertension risk in children after acknowledging the role of BMI and waist-to-height ratio., Methods: We studied a sample of 377 children 10.5 ± 2.3 years old who had a first diagnosis of hypertension or family history of cardiovascular disease. In this sample all weight classes were represented. The HOMA index was standardized by a linear regression model including BMI, waist-to-height ratio and pubertal status., Results: The role of BMI and waist-to-height ratio on the risk of prehypertension and hypertension was confirmed by univariate logistic regression models, odds ratio of 1.59 [95% confidence interval (CI) = 1.27-2.00] for BMI, and 1.56 (95% CI = 1.06-2.31) for waist-to-height ratio (>50 vs. ≤50%). When standardized HOMA index was added to BMI or waist-to-height ratio in a multivariate model, it gave a significant independent contribution to explain the risk of prehypertension and hypertension. Odds ratio was 1.23 (95% CI = 1.01-1.51) in the model with BMI, and 1.23 (95% CI = 1.01-1.50) in the model with waist-to-height ratio. The role of HOMA index was confirmed when continuous values of systolic and diastolic blood pressure (standardized by age, sex and height) were analysed, instead of hypertension category., Conclusions: These results strongly support the hypothesis that in children, insulin resistance plays a role on hypertension independently from obesity, fat distribution and puberty across weight classes.

Background: To assess the prevalence of hypertension (H), prehypertension (PH), and transient elevated blood pressure (TH) and their relationship with weight class and waist circumference (WC) in an unselected population of Northern Italian children., Methods: A cross-sectional study was conducted in 5,131 children (5-11 years). Weight class was defined according to the International Obesity Task Force references, H and PH according to the National High Blood Pressure Education Program. A child was classified as having PH or H when systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) at first screening were > or =90th percentile and the mean of three subsequent measures was between the 90th and 95th or > or =95th percentile, respectively. When BP values at the first screening were > or =90th percentile but the mean of three subsequent measures was <90th percentile the child was classified as having TH., Results: A proportion of 3.4% presented H, 2.7% PH, and 10.4% TH, 20% overweight, and 6% obesity. Weight class and WC were significantly associated to an increased risk of falling into any of the hypertensive categories. In children with TH BP z-scores of the mean of the three subsequent measurements following the first screening were significantly higher than BP z-scores observed in normotensive children (P value <0.001)., Conclusions: Weight class and WC are associated with BP. This is observed not only for H but also for PH, and for nonsustained forms of H. Prospective studies are needed to assess whether children with PH and TH will develop sustained H.

Background: Pulse wave velocity (PWV) assessment represents a simple method to estimate arterial distensibility. At present, carotid-femoral PWV (cf-PWV) is considered the gold standard method in the non-invasive evaluation of the elastic properties of the aorta. On the other hand, the mechanical properties of muscular arteries can be evaluated on the axillo-brachial-radia axis by estimating the carotid-radial PWV (cr-PWV). While a number of studies have addressed these issues in adults, limited information is available on the respective features of cf-PWV and cr-PWV and on their modulating factors in children and adolescents at increased cardiovascular risk. Methods: The mechanical properties of the predominantly elastic (aorta) and muscular (axillo−brachial−radial axis) arteries were evaluated in a pediatric population characterized by either elevated blood pressure (BP) or excess body weight, and the main factors affecting cf-PWV and cr-PWV values in these individuals were investigated. Results: 443 children and adolescents (median age 11.5 years, 43.3% females) were enrolled; 25% had BP values >90th percentile and 81% were excess weight. The cf-PWV values were significantly lower than the cr-PWV values: median (Q1–Q3) = 4.8 m/s (4.3–5.5) and 5.8 m/s (5.0–6.5), respectively (p < 0.001). The pubertal development (p < 0.03), systolic BP and diastolic BP z-scores (p = 0.002), heart rate (p < 0.001), and waist-to-height ratio (p < 0.005) were significantly associated with cf-PWV values. No significant association was found between BMI z-score and cf-PWV. Predictors of high cf-PWV (>95th percentile) were the heart rate (OR 1.07, 95%CI 1.04–1.10, p < 0.001) and waist-to-height ratio (OR 1.06, 95%CI 1.0–1.13, p = 0.04). The variables significantly related with cr-PWV values were diastolic BP z-score (p = 0.001), heart rate (p < 0.01), and HOMA index (p < 0.02). No significant association was found between the cr-PWV and BMI z-score or waist-to-height ratio. Conclusions: Systolic and diastolic BP values and central obesity are associated with aortic stiffness in a population of children and adolescents at increased cardiovascular risk. In contrast, diastolic BP, heart rate, and levels of insulin resistance appear to be related to distensibility of the upper limb vascular district. [ABSTRACT FROM AUTHOR]

Excess weight and high waist circumference (WC) are associated with increased blood pressure (BP), starting from the pediatric age. Insulin resistance is associated with elevated BP in childhood. The aim of the study was to assess the role of insulin resistance in mediating the relationship between body mass index (BMI), WC, and BP values in a pediatric population referred to a cardio-pediatric center for the presence of one or more cardiovascular risk factors. In 419 children (mean age 10.7 [standard deviation, SD 2.5] years), the following parameters were collected both in basal conditions and after 18.6 (SD 9.3) months of follow-up during which a treatment based on lifestyle and dietary modifications was given: systolic and diastolic BP (SBP and DBP), WC, plasma glucose, and insulin values. The HOMA (Homeostasis Model Assessment)-index was considered as an expression of insulin resistance. At baseline there was a significant correlation between HOMA-index and SBP z-score (β = 0.081, p = 0.003), and insulin resistance was a mediator of the relationship between BMI and SBP z-score (p = 0.015), and between waist circumference to height (WtHr) and SBP z-score (p = 0.008). The effect of BMI z-score modifications on SBP z-score changes from baseline to follow-up was totally mediated by HOMA-index changes (p = 0.008), while HOMA-index only partially mediated the effect of WtHr modifications on SBP z-score changes (p = 0.060). Our study strongly suggests that, in a pediatric population at cardiovascular risk, the HOMA-index is an important mediator of the relationship between BMI, WC and SBP. [ABSTRACT FROM AUTHOR]

In 2007 the International Diabetes Federation (IDF) proposed single blood pressure (BP) cutpoints (systolic: ≥130 mm Hg and diastolic: ≥85 mm Hg) for the diagnosis of high blood pressure (HBP) in adolescents. Before this proposal, HBP had been defined as BP at or above the 95th percentile for age, sex, and height percentile (reference standard). In this study, we evaluated the risk for misclassification when using the IDF single-cutpoints criteria. We first applied the IDF criteria to a reconstructed population with the same age, sex, and height distribution as the population used to develop the reference standard. The proposed single cutpoints corresponded to percentiles from the 81.6th to 99.9th for systolic BP and from the 92.9th to 98.9th for diastolic BP in the reconstructed population. Using IDF criteria, there were high false-negative fractions for both systolic and diastolic BP (from 54% to 93%) in 10- to 12-year-olds and a false-positive fraction up to 35% in older subjects. We then applied the IDF criteria to 1,162 overweight/obese adolescents recruited during 1998-2000 from pediatric clinical centers in Milano, Varese, and Modena in Italy and in Zaragoza, Spain. Overall false-negative and false-positive fractions were 22% and 2%, respectively; negative predictive values were especially low for 10- to 12-year-old subjects. The use of IDF's single cutpoints carries a high risk of misclassification, mostly due to false negatives in younger subjects. The effort to simplify diagnosis could be overcome by the risk of undiagnosed HBP. [ABSTRACT FROM AUTHOR]

Primary hypertension is a growing concern in children because of the obesity epidemic largely attributable to western lifestyles. Serum uric acid is known to be influenced by dietary habits, correlates with obesity, and could represent a risk factor for hypertension. Preliminary studies in children highlighted uric acid as a potentially modifiable risk factor for the prevention and treatment of hypertension. The effect of lifestyle changes (increase of physical activity and dietary modifications) on blood pressure values, weight status, and serum uric acid levels in a cohort of 248 children referred for cardiovascular risk assessment were evaluated over a mean 1.5-year follow-up. At baseline, 48% of children were obese and 50% showed blood pressure values >90th percentile. At follow-up, a significant improvement in weight class (24% obese;P<0.0001) and blood pressure category (22% >90th percentile;P<0.0001) was found. Systolic blood pressure z-score (P<0.0001), uric acid value (P=0.0056), and puberty at baseline (P=0.0048) were independently associated with higher systolic blood pressure z-score at follow-up, whereas a negative association was observed with body mass index z-score decrease during follow-up (P=0.0033). The risk of hypertension at follow-up was associated with body mass index (P=0.0025) and systolic blood pressure (P<0.0001) z-score at baseline and inversely related to delta body mass index (P=0.0002), whereas the risk of showing hypertension ≥99th percentile was more than doubled for each baseline 1 mg/dL increase of serum uric acid (P=0.0130). Uric acid is a powerful determinant of blood pressure over time, independent of lifestyle modifications. [ABSTRACT FROM AUTHOR]

BACKGROUND Adiponectin (AD) reduces the risk of hypertension because of its anti-inflammatory, antiatherogenic, and insulin-sensitizing properties. The study described here was done to evaluate the interrelationships of AD, blood pressure (BP), obesity, body-fat distribution, puberty, and insulin resistance in a selected group of children. METHODS The study was a cross-sectional, observational study of 186 children ranging in age from 5–18 years and grouped according to weight class (obese (OB), n = 100; normal weight (NW), n = 86) and BP category (hypertensive (HT) n = 79; normotensive (NT); n = 107). The children were also classified on the basis of fat distribution (waist circumference/height ratio). Their blood glucose, insulin, and AD concentrations were assayed, and their homeostatic model assessment (HOMA) index was calculated as an estimate of insulin resistance. RESULTS Serum AD was lower in OB–HT (7,111±4,163ng/ml) than in NW–NT (12,622±6,276ng/ml) children (P < 0.0001). Intermediate values of AD were found in OB–NT (9,099±3,988ng/ml) and NW–HT (9,808±4,211ng/ml) children. Weight and waist circumference-to-height ratio, BP category, and pubertal stage were all independently and inversely associated with serum levels of AD (P < 0.02). In a logistic regression model, after adjustment for body mass index (BMI) and waist circumference/height ratio, serum levels of AD maintained an independent association with hypertension (P < 0.05), as did also the HOMA index (P < 0.05). A reduction of 10 times (i.e., one unit on the log10 scale) in AD serum levels was associated with a 50% increased probability of having hypertension. CONCLUSIONS In childhood, serum levels of AD are inversely related to hypertension. This relationship is partly independent of obesity, fat distribution, and insulin resistance. Low values of AD in both OB and NW children are associated with a higher probability of hypertension. [ABSTRACT FROM PUBLISHER]

Background: High blood pressure (BP) and excess weight can lead to early cardiovascular organ damage already in children. Carotid-femoral pulse wave velocity (cf-PWV) is the non-invasive gold standard method for assessing aortic stiffness, while carotid-radial PWV (cr-PWV) provides information on the distensibility of the upper limb arteries. The aim of this study was to evaluate the relationship of BP and BMI z-scores with arterial stiffness and left ventricular mass index (LVMI) in a pediatric population. Methods: In 343 children (57.7% males; age ± SD 11.7 ± 2.9 years), systolic (SBP) and diastolic (DBP) BP, BMI, cf-PWV, cr-PWV and LVMI were measured. A multiple linear regression model was used to assess the impact of BMI and SBP (or DBP) z-scores on cf-PWV, cr-PWV and LVMI. Results: About 21% of children were normal weight, 34% were overweight and 45% obese. Adjusted for possible confounders, SBP and DBP z-scores were significantly associated with cf-PWV (p < 0.001), while only DBP z-scores were related to cr-PWV (p < 0.01). BMI was neither associated with cf-PWV nor with cr-PWV values but was a strong predictor of LVMI (<0.001), whereas cardiac mass and BP z-scores were not related. Conclusions: Our study suggests that, in children, elevated BP values and excess weight may have different effects on the heart and the vessels in causing early cardiovascular alterations. [ABSTRACT FROM AUTHOR]