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OBJECTIVES: To correlate cardiovascular risk factors (e.g., hypertension, obesity, hypercholesterolemia, hypertriglyceridemia, hyperglycemia, sedentariness) in childhood and adolescence with the occurrence of cardiovascular disease. SOURCES: A systematic review of books and selected articles from PubMed, SciELO and Cochrane from 1992 to 2012. SUMMARY OF FINDINGS: Risk factors for atherosclerosis are present in childhood, although cardiovascular disease arises during adulthood. This article presents the main studies that describe the importance of investigating the risk factors for cardiovascular diseases in childhood and their associations. Significant rates of hypertension, obesity, dyslipidemia, and sedentariness occur in children and adolescents. Blood pressure needs to be measured in childhood. An increase in arterial blood pressure in young people predicts hypertension in adulthood. The death rate from cardiovascular disease is lowest in children with lower cholesterol levels and in individuals who exercise regularly. In addition, there is a high prevalence of sedentariness in children and adolescents. CONCLUSIONS: Studies involving the analysis of cardiovascular risk factors should always report the prevalence of these factors and their correlations during childhood because these factors are indispensable for identifying an at-risk population. The identification of risk factors in asymptomatic children could contribute to a decrease in cardiovascular disease, preventing such diseases as hypertension, obesity, and dyslipidemia from becoming the epidemics of this century.

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BACKGROUND: Down syndrome is known to cause premature aging in several organ systems. However, it remains unclear whether this aging effect also affects the structure and function of the large arterial trunks. In this controlled study, the possibility of changes in the large arteries due to aging was evaluated in patients with Down syndrome. METHODS: Eighty-two subjects of both genders were selected. The Down syndrome group had 41 active subjects consisting of 19 males and 22 females (mean age 21 ± 1, range 13-42 years) without cardiovascular complications and who did not use vasoactive drugs. The control group consisted of 41 healthy individuals without trisomy 21 of the same gender and age as the Down syndrome group and who did not use vasoactive medication. Carotid-femoral pulse wave velocity was obtained as an index of aortic stiffness using an automatic noninvasive method. RESULTS: Individuals with Down syndrome had significantly lower blood pressure than those in the control group. Systolic blood pressure for the Down syndrome group and control group was 106 ± 2 mmHg vs 117 ± 2 mmHg (P < 0.001), respectively; diastolic blood pressure was 66 ± 2 mmHg vs 77 ± 2 mmHg (P < 0.001); and mean arterial pressure was 80 ± 1 mmHg vs 90 ± 1 mmHg (P < 0.001). Only age and systolic blood pressure were shown to correlate significantly with pulse wave velocity, but the slopes of the linear regression curves of these two variables showed no significant difference between the two study groups. Pulse wave velocity, which was initially significantly lower in the Down syndrome group (7.51 ± 0.14 m/s vs 7.84 ± 0.12 m/s; P <0.05), was similar between the groups after systolic blood pressure adjustment (7.62 ± 0.13 m/s vs 7.73 ± 0.13 m/s). CONCLUSION: Despite evidence in the literature that patients with Down syndrome undergo early aging, this process does not seem to affect the large arterial trunks, given that values of carotid-femoral pulse wave velocity were similar in individuals with or without trisomy 21. Considering that Down syndrome presents with chronic hypotension, it is reasonable to propose that the prolonged reduction of arterial distending pressure may contribute to functional preservation of the arteries in patients with Down syndrome.

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OBJECTIVE: Maximum oxygen uptake is emerging as the measure of preference for expressing cardiorespiratory fitness for the purposes of surveys of physical activity, due to its greater objectivity and lower propensity to errors. Studies indicate that this measure is better correlated with cardiovascular diseases. This paper proposes to relate cardiovascular risk factors in adolescents with their level of cardiorespiratory fitness. METHODS: The study enrolled 380 schoolchildren, 177 boys and 203 girls (10 to 14 years old), who were divided into two groups according to their cardiorespiratory fitness. Anthropometric assessment was carried out, hemodynamic measurements (arterial pressure and heart rate) were taken, cardiopulmonary exercise testing was performed and biochemical tests were run (triglycerides, total and partial cholesterol). RESULTS: Among the boys, significant differences were observed between boys defined as "weak" and those classed as "not weak" in terms of baseline heart rate, maximum oxygen uptake, body mass index and triglycerides. Among the girls, significant differences were detected between baseline heart rates, maximum oxygen uptake and body mass indices. In both sexes, the group classified as "weak" exhibited a significantly greater number of overweight individuals that the "not weak" group (chi2 = 25.242; p = 0.000; chi2 = 12.683; p = 0.000, for boys and girls, respectively). A significant association between cardiorespiratory fitness and triglycerides (chi2 = 3.944; p = 0.047) was observed among the boys only. CONCLUSIONS: A low level of cardiorespiratory fitness appears to have a negative influence on cardiovascular risk factors among adolescents, especially with relation to overweight in both sexes and to biochemical profile in the male sex, providing evidence of the need for early preventative interventions.

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OBJETIVO: O consumo máximo de oxigênio tem sido sugerido como medida preferível em relação a questionários de atividade física para expressar a aptidão cardiorrespiratória, por sua maior objetividade e menor possibilidade de erros. Estudos indicam que essa medida se correlaciona melhor com as doenças cardiovasculares. Este trabalho propõe-se a associar fatores de risco cardiovasculares em adolescentes ao nível de aptidão cardiorrespiratória. MÉTODOS: Foram selecionados 380 escolares, 177 meninos e 203 meninas (10 a 14 anos), que foram divididos em dois grupos de acordo com a aptidão cardiorrespiratória. Realizou-se avaliação antropométrica, medidas hemodinâmicas (pressão arterial e freqüência cardíaca), teste cardiopulmonar e perfil bioquímico (triglicerídeos, colesterol total e frações). RESULTADOS: Nos meninos, observou-se diferença significativa entre grupo "fraco" e "não fraco" para as médias de freqüência cardíaca basal, consumo máximo de oxigênio, índice de massa corporal e triglicerídeos. Nas meninas, as diferenças significativas foram nas médias de freqüência cardíaca basal, consumo máximo de oxigênio e índice de massa corporal. Em ambos os sexos, o grupo classificado como "fraco" apresentou maior número significativo de indivíduos com excesso de peso em relação ao grupo "não fraco" (x² = 25,242; p = 0,000; x² = 12,683; p = 0,000, para meninos e meninas, respectivamente). Associação significativa entre aptidão cardiorrespiratória e triglicerídeos (x² = 3,944; p = 0,047) observou-se apenas para o sexo masculino. CONCLUSÕES: A aptidão cardiorrespiratória mais baixa parece ter influência negativa sobre os fatores de risco cardiovasculares em adolescentes, especialmente em relação ao excesso de peso em ambos os gêneros e ao perfil bioquímico no sexo masculino, evidenciando para a necessidade de intervenções preventivas precoces.

OBJECTIVE: Maximum oxygen uptake is emerging as the measure of preference for expressing cardiorespiratory fitness for the purposes of surveys of physical activity, due to its greater objectivity and lower propensity to errors. Studies indicate that this measure is better correlated with cardiovascular diseases. This paper proposes to relate cardiovascular risk factors in adolescents with their level of cardiorespiratory fitness. METHODS: The study enrolled 380 schoolchildren, 177 boys and 203 girls (10 to 14 years old), who were divided into two groups according to their cardiorespiratory fitness. Anthropometric assessment was carried out, hemodynamic measurements (arterial pressure and heart rate) were taken, cardiopulmonary exercise testing was performed and biochemical tests were run (triglycerides, total and partial cholesterol). RESULTS: Among the boys, significant differences were observed between boys defined as "weak" and those classed as "not weak" in terms of baseline heart rate, maximum oxygen uptake, body mass index and triglycerides. Among the girls, significant differences were detected between baseline heart rates, maximum oxygen uptake and body mass indices. In both sexes, the group classified as "weak" exhibited a significantly greater number of overweight individuals that the "not weak" group (x² = 25.242; p = 0.000; x² = 12.683; p = 0.000, for boys and girls, respectively). A significant association between cardiorespiratory fitness and triglycerides (x² = 3.944; p = 0.047) was observed among the boys only. CONCLUSIONS: A low level of cardiorespiratory fitness appears to have a negative influence on cardiovascular risk factors among adolescents, especially with relation to overweight in both sexes and to biochemical profile in the male sex, providing evidence of the need for early preventative interventions.

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OBJETIVO: A identificação de valores populacionais do consumo máximo de oxigênio (VO2 máx) auxilia nos estudos que se propõem a relacionar a aptidão física ao risco cardiovascular, bem como na prescrição do exercício e na análise do efeito do treinamento. Em amostras de adolescentes da população brasileira, ainda não existem informações para classificação desse parâmetro. Portanto, a proposta inédita deste estudo foi de determinar os valores médios de VO2 máx de uma amostra da população brasileira. MÉTODOS: Foi selecionada aleatoriamente uma amostra de 380 escolares (177 meninos e 203 meninas) da rede pública de Vitória (ES), com idade de 10 a 14 anos. Após avaliação antropométrica, foram submetidos a teste cardiopulmonar para medida direta do VO2 máx, cujos valores foram classificados de acordo com o quintil calculado a partir da amostra estudada. RESULTADOS: Os valores médios de VO2 máx encontrados para os meninos foram de 42,95 a 49,55 mL.kg-1.min-1 e, nas meninas, entre 36,76 e 38,29 mL.kg-1.min-1. CONCLUSÕES: O presente trabalho propõe faixas de valores médios de VO2 máx como parâmetro para classificação de aptidão cardiorrespiratória, além de contribuir para a definição dos valores de normalidade da população brasileira. Essa classificação auxilia também no estabelecimento de pontos de corte para estudos posteriores.

OBJECTIVE: The identification of populational levels of maximum oxygen uptake (VO2max) is an aid to studies that propose to relate physical fitness to cardiovascular risk, and also for prescribing exercise and analyzing the effects of training. To date, there is no information with which this parameter can be classified in samples of adolescents from the Brazilian population. This study is, therefore, the first to propose the determination of mean VO2max levels in a sample of the Brazilian population. METHODS: A sample of 380 schoolchildren (177 boys and 203 girls, aged 10 to 14 years) was selected at random from public schools in Vitória, ES. After anthropometric assessment they underwent cardiopulmonary exercise testing, VO2max was measured directly and results were classified according to quintiles calculated from the study sample. RESULTS: The mean VO2max values observed ranged from 42.95 to 49.55 mL.kg-1.min-1 for boys and from 36.76 to 38.29 mL.kg-1.min-1 for girls. CONCLUSIONS: This paper proposes mean VO2max ranges as a classification parameter for cardiorespiratory fitness, in addition to contributing to a definition of normal values for the Brazilian population. This classification will also be of use for establishing cutoff points in future studies.

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OBJECTIVE: The identification of populational levels of maximum oxygen uptake (VO(2max)) is an aid to studies that propose to relate physical fitness to cardiovascular risk, and also for prescribing exercise and analyzing the effects of training. To date, there is no information with which this parameter can be classified in samples of adolescents from the Brazilian population. This study is, therefore, the first to propose the determination of mean VO(2max) levels in a sample of the Brazilian population. METHODS: A sample of 380 schoolchildren (177 boys and 203 girls, aged 10 to 14 years) was selected at random from public schools in Vitória, ES. After anthropometric assessment they underwent cardiopulmonary exercise testing, VO(2max) was measured directly and results were classified according to quintiles calculated from the study sample. RESULTS: The mean VO(2max) values observed ranged from 42.95 to 49.55 mL x kg(-1) x min(-1) for boys and from 36.76 to 38.29 mL x kg(-1) x min(-1) for girls. CONCLUSION: This paper proposes mean VO(2max) ranges as a classification parameter for cardiorespiratory fitness, in addition to contributing to a definition of normal values for the Brazilian population. This classification will also be of use for establishing cutoff points in future studies.

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