Abdominal obesity: prevalence, sociodemographic- and lifestyle-associated factors in adolescents

Objectives: The aim of this study was to determine the prevalence of abdominal obesity and its associated factors among adolescents, independent of confounders. Methods: A sample of 14–17-year-old individuals (n=1.231), who were students from Londrina/PR-Brazil public schools, was studied. A questionnaire about physical activity, sedentary behaviour and socioeconomic conditions was applied. Anthropometry was composed of body weight (kg), height (m), body mass index (BMI=kg/m²) and waist circumference (cm). The association of abdominal obesity and independent variables was assessed using the chi-square test and the magnitude of associations was verified using Binary Logistic Regression in an unadjusted model and adjusted for confounders (gender, age, socioeconomic status, physical activity and sedentary behaviour). The confidence interval and statistical significance were set at 95% and 5%, respectively, using SPSS v15.0. Results: The abdominal obesity prevalence was 17.5% (CI = 15.4%–19.6%), and was higher in boys than in girls. Adolescents with abdominal obesity had higher values of body weight, height, body mass index and sedentary behaviour compared to eutrophic individuals. Being male increased the risk of abdominal obesity by 36% in adolescents. This risk was two times higher in those with high levels of sedentary behaviour. Conclusion: Abdominal obesity was significantly associated with gender and high levels of sedentary behaviour, regardless of confounding factors. Lifestyle habits are important modifiable risk factors that can effectively contribute to the reduction of obesity from an early age

Comparison of resting heart rate measured using a cardiac monitor and an oscilometric device in adolescents: analysis of sensitivity and specificity

Study design: Experimental study Objectives: To assess the consistency and efficiency of an oscillometric device for measuring resting heart rate in adolescents. Methods: Data from adolescents of both sexes aged between 10 and 15 years were analyzed. Weight was measured using a digital scale and height, a stadiometer. Body mass index was calculated by dividing body weight by the height squared. The resting heart rate was measured with a heart rate monitor and an oscillometric device for measuring blood pressure. The mean and standard deviation were used to describe the characteristics of the sample. Pearson’s correlation was used to examine the relationship between the two devices. Reproducibility was assessed by the intraclass correlation coefficient and efficiency by the receiver operating characteristic curve. Results: Moderate/high correlations were found (r=0.80) between the heart rate monitor and oscillometric device. The intraclass correlation coefficient showed values of 0.88 (0.66–0.96) for girls and 0.90 (0.82–0.95) for boys. The sensitivity was 70.0 (34.8–93.3) and 80.4 (28.4– 99.5) and the specificity 86.6 (69.3–96.2) and 90.0 (55.5–99.7) for boys and girls respectivelyDesenho do estudo: Estudo experimental Objetivos: avaliar a consistência e eficiência de um aparelho oscilométrico para medir frequência cardíaca em repouso em adolescentes. Métodos: Os dados de adolescentes de ambos os sexos, com idade entre 10 e 15 anos foram analisados. O peso foi medido utilizando uma balança digital e altura, um estadiômetro. Índice de massa corporal foi calculado dividindo-se o peso corporal pela altura ao quadrado. A frequência cardíaca de repouso foi medida com um monitor de frequência cardíaca e um aparelho oscilométrico para medir a pressão arterial. A média e o desvio padrão foram utilizados para descrever as características da amostra. A correlação de Pearson foi usada para examinar a relação entre os dois dispositivos. A reprodutibilidade foi avaliada pelo coeficiente de correlação intraclasse e eficiência pela curva ROC. Resultados: média / alta correlações foram encontrados (r = 0,80) entre o monitor de frequência cardíaca e aparelho oscilométrico. O coeficiente de correlação intraclasse apresentaram valores de 0,88 (0,66-0,96) para as meninas e 0,90 (0,82-0,95) para os meninos. A sensibilidade foi de 70,0 (34,8- 93,3) e 80,4 (28.4- 99.5) e a especificidade de 86,6 (69,3-96,2) e 90,0 (55,5-99,7) para meninos e meninas, respectivament