BackgroundObesity has been identified as an important risk factor in the development of cardiovascular diseases; however, other factors, combined or not with obesity, can influence cardiovascular risk and should be considered in cardiovascular risk stratification in pediatrics. ObjectiveTo analyze the association between anthropometry measures and cardiovascular risk factors, to investigate the determinants to changes in blood pressure (BP), and to propose a prediction equation to waist circumference (WC) in children and adolescents. MethodsWe evaluated 1,950 children and adolescents, aged 7 to 18 years. Visceral fat was assessed by WC and waist hip relationship, BP and body mass index (BMI). In a randomly selected subsample of these volunteers (n = 578), total cholesterol, glucose and triglycerides levels were evaluated. ResultsWC was positively correlated with BMI (r = 0.85; p < 0.001) and BP (SBP r = 0.45 and DBP = 0.37; p < 0.001). Glycaemia and triglycerides showed a weak correlation with WC (r = 0.110; p = 0.008 e r = 0.201; p < 0.001, respectively). Total cholesterol did not correlate with any of the variables. Age, BMI and WC were significant predictors on the regression models for BP (p < 0.001). We propose a WC prediction equation for children and adolescents: boys: y = 17.243 + 0.316 (height in cm); girls: y = 25.197 + 0.256 (height in cm). ConclusionWC is associated with cardiovascular risk factors and presents itself as a risk factor predictor of hypertension in children and adolescents. The WC prediction equation proposed by us should be tested in future studies.

Background: During childhood and adolescence, physical inactivity, excess weight, and poor nutrition are risk factors for chronic diseases, especially obesity, hypertension, and diabetes mellitus. Early intervention can prevent the development of these complications.

CONTEXT AND OBJECTIVE: Studies have demonstrated that metabolic complications from child obesity, although silent, increase the risk of development of cardiovascular diseases in adulthood. The present paper sought to describe the prevalence of overweight/obesity and analyze the possible relationship between obesity and other cardiovascular risk factors among children and adolescents. DESIGN AND SETTING: Cross-sectional study, conducted in a university. METHODS:The study included 564 children and adolescents, aged 8 to 17 years. Body mass index and waist circumference were used to evaluate obesity. Other cardiovascular risk factors were evaluated, like systolic and diastolic blood pressure, glycemia, triglycerides and total cholesterol. Descriptive analysis was used for sample characterization, the chi-square test for categorical variables and Pearson's linear correlation for evaluating the relationship between obesity indicators and other cardiovascular risk factors. RESULTS: High prevalence of overweight/obesity was found among the schoolchildren (25.3% among the boys and 25.6% among the girls), along with abdominal obesity (19.0%). The overweight/obese schoolchildren presented higher percentages for the pressure and biochemical indicators, compared with underweight and normal-weight schoolchildren. Body mass index and waist circumference showed a weak correlation with the variables of age and systolic and diastolic blood pressure (P < 0.001), but there was no correlation between these obesity indices and biochemical variables. CONCLUSION: The high prevalence of overweight/obesity and its relationship with other cardiovascular risk factors demonstrate that it is necessary to develop intervention and prevention strategies from childhood onwards, in order to avoid development of chronic-degenerative diseases in adulthood.RESUMO CONTEXTO E OBJETIVO: Estudos demonstram que as complicações metabólicas da obesidade infantil, mesmo silenciosas, aumentam o risco de desenvolvimento de doenças cardiovasculares na fase adulta. O presente estudo buscou descrever a prevalência de sobrepeso/obesidade, analisando possível relação entre obesidade e demais fatores de risco cardiovascular em crianças e adolescentes. TIPO DE ESTUDO E LOCAL: Estudo transversal, realizado em universidade. MÉTODOS: Foram incluídas 564 crianças e adolescentes de 8 a 17 anos. Foi utilizado o índice de massa corporal e a circunferência da cintura para avaliar obesidade. Outros fatores de risco cardiovasculares foram avaliados, como pressão arterial sistólica e diastólica, glicemia, triglicerídeos e colesterol total. Foi utilizada a análise descritiva para caracterização da amostra, teste de qui-quadrado para variáveis categóricas e correlação linear de Pearson para avaliar a relação entre os indicadores de obesidade e demais fatores de risco cardiovasculares. RESULTADOS: Foi encontrada alta prevalência de sobrepeso/obesidade entre os escolares (25,3% entre os meninos e 25,6% entre as meninas), assim como obesidade abdominal (19,0%). Escolares c...

Background The presence of dyslipidemia and behavioral aspects are determinants of cardiovascular risk, especially in childhood and adolescence. Objective To verify possible relationships between dyslipidemia, cultural factors, and cardiorespiratory fitness (CRF) in schoolchildren. Methods This cross-sectional study evaluated a sample of 1,254 children and adolescents between the ages of 7 and 17 from the South of Brazil, 686 of whom were female. Dyslipidemia was defined as increased levels of at least one of the following lipid profile parameters: triglycerides (TG), total cholesterol (TC) and fractions of high (HDL-c) and low-density lipoprotein (LDL-c). Cultural aspects were evaluated by a self-reported questionnaire. Data were analyzed by logistic regression, considering the odds ratios (OR) and confidence intervals (CI) at 95%. Results The results revealed a high prevalence of dyslipidemia (41.9%), which was associated with female sex (OR: 1.56; IC: 1.24-1.96) and overweight/obese status (OR: 1.55; IC: 1.20-2.00). When lipid profile parameters were evaluated separately, high levels of LDL-c were observed to be associated with sedentary school transport (OR: 1.59; IC: 1.20-2.09). Schoolchildren who were overweight/obese had higher chances of elevated levels of TC (OR: 1.40; IC: 1.07-1.84) and TG (OR: 3.21; IC: 1.96-5.26). HDL-c was shown to be related to high television time (OR: 1.59; IC: 1.00-2.54). Conclusion Alterations in lipid parameters are associated with cultural factors, especially those related to sedentary lifestyle and low levels of CRF.

Background Studies in adults have shown a relationship between high blood pressure and hyperuricemia, but few studies have investigated this association in children and adolescents. The aim of the present study was to associate urate concentration with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in schoolchildren. Methods This cross-sectional study used a sample of 2335 schoolchildren in basic education between 7 and 17 years old. Blood pressure was classified by percentile according to Brazilian parameters for sex and age, reclassified into two categories: normal and borderline/hypertension. Blood collection to obtain serum for urate concentration analysis was performed after a 12-h fast. Values above 5.5 mg/dL were considered hyperuricemia. Descriptive data were presented in frequency and percentage. Linear regression and Poisson regression (prevalence ratio [PR]) was used to test the association between urate concentration and blood pressure. Results Urate concentration was weakly associated with SBP (β: 0.05; 95% CI: 0.02–0.08) and DBP (β: 0.03; 95% CI: 0.01–0.05) z-scores. Schoolchildren with hyperuricemia had a higher prevalence of high SBP (PR: 1.12; p<0.001) and DBP (PR: 1.08; p<0.001). Conclusions Elevated urate concentration is associated with altered blood pressure in schoolchildren.

This longitudinal study evaluated the association between the incidence of youth overweight/obesity (Ow/Ob) and low levels of cardiorespiratory fitness (CRF) over 4 years and youths' and their parents' demographic and nutritional characteristics. The randomized sample comprised 398 youth, aged 7-17 years at baseline, from a city in southern Brazil. Subjects were classified as being Ow/Ob according to international body mass index (BMI) parameters. Parental weight and height were determined by direct questioning. Youth CRF was measured by a 9-minute walk-and-run test. The cumulative incidences of Ow/Ob and of low CRF levels were 25.1% and 20.5%, respectively. Relative to other youth, youth who were classified as "unhealthy" at baseline (with respect to CRF) and by the fourth year were more likely to be classified as Ow/Ob (relative risks: 1.12 and 1.10, respectively). Youth whose mothers were categorized as Ow/Ob were at higher risk of being classified as Ow/Ob than youth whose mothers had normal BMIs (relative risks: 1.19 at baseline and 1.20 in the fourth year). The incidence of Ow/Ob among the former youth was associated with low CRF levels and with maternal Ob.

The essential hypertension has been associated with membrane cell damage. The aim of the present study is investigate the relationship between erythrocyte Na+,K+-ATPase and lipoperoxidation in prehypertensive patients compared to normotensive status. The present study involved the prehypertensive patients (systolic: 136 ± 7 mmHg; diastolic: 86.8 ± 6.3 mmHg; n = 8) and healthy men with normal blood pressure (systolic: 110 ± 6.4 mmHg; diastolic: 76.1 ± 4.2 mmHg; n = 8) who were matched for age (35 ± 4 years old). The venous blood samples of antecubital vein (5 mL) were collected into a tube containing sodium heparin as anticoagulant (1000 UI), and erythrocyte ghosts were prepared for quantifying Na+,K+-ATPase activity. The extent of the thiobarbituric acid reactive substances (TBARS) was determined in plasma. The statistical analysis was carried out by Student's t-test and Pearson's correlation coefficient. A P < 0.05 was considered significant. The Na+,K+-ATPase activity was lower in prehypertensive patients compared with normotensive subjects (4.9 versus 8.0 nmol Pi/mg protein/min; P < 0.05). The Na+,K+-ATPase activity correlated negatively with TBARS content (r = −0.6; P < 0.05) and diastolic blood pressure (r = −0.84; P < 0.05). The present study suggests that Na+,K+-ATPase activity reduction and elevation of the TBARS content may underlie the pathophysiological aspects linked to the prehypertensive status.

Introdução: O sobrepeso e a obesidade são considerados problemas de saúde pública e têm sido ligados a baixos níveis de atividade física, tornando-se fatores de risco à saúde e contribuindo para o aparecimento de doenças crônicas. Bons níveis de aptidão física também são fatores que reduzem doenças crônicas. Objetivo: Avaliar a associação entre obesidade e aptidão física relacionada à saúde em escolares de 10 a 13 anos de idade. Casuística e métodos: Estudo transversal composto por 785 escolares, de ambos os sexos, entre 10 e 13 anos de idade, pertencentes a escolas municipais e estaduais de Santa Cruz do Sul, RS – Brasil. Foram avaliados o Índice de Massa Corporal (IMC) de acordo com os parâmetros da Organização Mundial da Saúde, e as características de aptidão física de flexibilidade, resistência muscular e aptidão cardiorrespiratória (APCR) segundo os protocolos do Projeto Esporte Brasil. Resultados: Em ambos os sexos, os valores médios de Índice de Massa Corporal são superiores entre os adolescentes classificados na faixa de risco à saúde para resistência abdominal e aptidão cardiorrespiratória, em relação aos adolescentes na faixa saudável (p<0,05). Além disso, adolescentes com sobrepeso/obesidade apresentam maior prevalência de baixos níveis de resistência abdominal (10% para meninos e 20% para meninas) e de aptidão cardiorrespiratória (21% para meninos e 22% para meninas). Conclusão: A presença de sobrepeso e obesidade está associada com baixos níveis de resistência abdominal e de aptidão cardiorrespiratória, em escolares com 10 a 13 anos de idade.