Utility of anthropometric indicators to screen for clustered cardiometabolic risk factors in children and adolescents.

Background Anthropometric indicators are associated with cardiometabolic risk factors (CMRF), but there is no consensus as to which indicator is the most suitable to screen for clustered CMRF. This study aimed to evaluate the utility of five anthropometric indicators to screen for clustered CMRF in children and adolescents. Methods A cross-sectional study was conducted in 1139 schoolchildren aged 6-17 years from Northeastern Brazil. Body weight, height, waist circumference (WC) and subscapular (SSF) and triceps skinfold thickness (TSF) were measured. Body mass index (BMI) and waist-to-height ratio (WHtR) were calculated. The following CMRF were evaluated: elevated total cholesterol, low high-density lipoprotein-cholesterol (HDL-C), elevated low-density lipoprotein-cholesterol (LDL-C), high triglyceride concentration, hyperglycemia and high blood pressure. The participants were categorized into no CMRF, 1 CMRF, 2 CMRF and ≥3 CMRF. Receiver operating characteristic (ROC) curves were constructed to assess the accuracy of the anthropometric indicators in predicting CMRF for age group and sex. Results Poor associations were observed between the anthropometric indicators and 1 CMRF (accuracy of 0.49-0.64). The indicators showed moderate associations with 2 CMRF (accuracy of 0.57-0.75) and ≥3 CMRF (accuracy of 0.59-0.79). In general, TSF exhibited the worst performance in predicting CMRF, followed by WHtR. The highest accuracies were observed for BMI, WC and SSF, with no significant difference between these indicators. Conclusions The routine use of BMI, WC and SSF as epidemiological screening tools for clustered CMRF in childhood and adolescence should be encouraged.

Number of Daily Steps to Discriminate Abdominal Obesity in a Sample of Brazilian Children and Adolescents.

PURPOSE: Weight status-referenced pedometer step-count guidelines for young people have been developed for populations from high-income countries and may not be applicable to middle- and low-income countries. The objectives of this study were 1) to develop cut-off points for pedometer-determined step count in young Brazilians using waist circumference (WC) as a reference criterion, and 2) to analyze the capacity of previous recommendations to discriminate abdominal obesity in the sample studied. METHODS: A cross-sectional study was conducted on 1,044 schoolchildren (456 boys) aged 6-17 years from Northeastern Brazil. WC was measured and daily step counts were determined with a pedometer. RESULTS: The area under the curve (AUC) of step count was significant for boys (AUC = 0.55; 95%CI: 0.50-0.59) and girls (AUC = 0.57; 95%CI: 0.53-0.61). Our cut-off points (14,414 and 11,355 steps for boys and girls, respectively) were more balanced in terms of sensitivity and specificity compared with previous recommendations. The use of previous guidelines to classify step count in the sample provided very low sensitivity or specificity and wide variation in the prevalence of insufficient physical activity (39.3-77.0%). CONCLUSIONS: A universal step-count recommendation for young people may not be adequate and specific guidelines seem to be necessary for different countries or regions.

[Knowledge of pediatricians regarding physical activity in childhood and adolescence]. / Conhecimento de pediatras sobre a atividade física na infância e adolescência.

OBJECTIVE: To investigate the knowledge and guidance given by pediatricians regarding physical activity in childhood and adolescence. METHODS: A cross-sectional study involving a convenience sample of pediatricians (n=210) who participated in a national pediatrics congress in 2013. Sociodemographic and professional data and data regarding habitual physical activity and pediatricians' knowledge and instructions for young people regarding physical activity were collected using a questionnaire. Absolute and relative frequencies and means and standard deviations were calculated. RESULTS: Most pediatricians were females, had graduated from medical school more than 15 years ago, and had residency in pediatrics. More than 70% of the participants reported to include physical activity guidance in their prescriptions. On the other hand, approximately two-thirds of the pediatricians incorrectly reported that children should not work out and less than 15% answered the question about physical activity barriers correctly. With respect to the two questions about physical activity to tackle obesity, incorrect answers were marked by more than 50% of the pediatricians. Most participants incorrectly reported that 30 minutes should be the minimum daily time of physical activity in young people. Less than 40% of the pediatricians correctly indicated the maximum time young people should spend in front of a screen. CONCLUSIONS: In general, the pediatricians reported that they recommend physical activity to their young patients, but specific knowledge of this topic was limited. Programs providing adequate information are needed.