ABC | Volume 114, Nº3, March 2020

Original Article Santos et al. Waist circumference of children in Brazil Arq Bras Cardiol. 2020; 114(3):530-537 The present study circumscribed an area of 12 cities in the São Paulo State. We believe it may be representative of school children of a large area of Brazil, since it included the most significant number of children of private and governmental schools ever reported in Brazil. Moreover, São Paulo state has a high degree of miscegenation, and its countryside has an economic and social development comparable to the South and Southern Regions and even with many closer areas of the Central-West. As emphasized by several reports, the evaluation of cardiometabolic disorders in children is only feasible when specific references to the association between age, gender and ethnic origin and health risks are available. With a sample of 9,713 subjects from 2 to 18 years old, including 3,414 African‑American, 2,746 European-American, and 3,553 Mexican-American (MA), Fernandez et al. 14 have described and provided estimates of the distribution of WC percentiles curves widely used in different countries, the well‑knownNHANES data. On the 75 th and 90 th percentiles, MA girls showed the fastest overall increase among all girls. At any of the percentiles considered, MA persons showed the highest overall WC and the fastest overall rate of WC increase with age. This data supports the high WC percentiles among Brazilian children and the most significant increase among Brazilian girls. Based on the robust data they collected, Fernandez et al. 14 stressed that careful attention should be concentrated to children whose WC values fall in the 75 th and 90 th percentile, since this drop help identify children at risk for various comorbidities and they strongly suggest prevention actions [against these situations]. All percentiles values found in our study were higher than those described by Fernandez et al. 14 Among German children (6-10-year-old boys and girls), the 97 th WC percentile was associated with abdominal obesity. 50 Healthy lifestyle habits, including engaging in a healthy diet and physical activity, may lower the risk of becoming obese and developing related diseases. 51,52 The dietary and physical activity behaviors of children and adolescents are influenced by many societal environments, including families, communities, schools, child care settings, medical care providers, faith-based institutions, government agencies, the media, and the food and beverage industries and entertainment businesses. 53-56 Schools play a particularly critical role in establishing a safe and supportive environment with policies and practices that support healthy behaviors. They also provide opportunities for students to learn about and practice healthy eating and physical activity behaviors. 56 Therefore, the importance of the present study was to provide representative values of WC of our children that may be used as an assessment tool to help meet public health recommendations. Another significant contribution in the development of national epidemiological data is the Study of Cardiovascular Risks in Adolescents - (Portuguese acronym "ERICA" - Estudo de Riscos Cardiovasculares em Adolescentes). 57 It is a large cross-sectional study at the national and school-based levels and a pioneering study that aimed to assess the prevalence of cardiovascular risk factors, including metabolic syndrome components in approximately 85,000 students, aged 12 to 17 years. A recent publication of ERICA described that the prevalence of metabolic syndrome was around 2,6% and that the most common combinations of elements, referring to 3/4 of combinations, were: enlarged waist circumference (WC), low HDL-cholesterol (HDL-c) and high blood pressure; followed by enlarged WC, low HDL-c and high triglycerides; and enlarged WC, low HDL-c, high triglycerides, and blood pressure. Therefore, the results of ERICA reinforce the importance of WC as a potential indication of a more global disarrangement that could determine the metabolic syndrome. The main limitation of the present study is the described percentile curves based on a sample of children from only one state, São Paulo, and not derivated from randomly selected regions across Brazil. This fact may restrict the generalization of our results to children across the entire country. Furthermore, to validate the cut-off points for overweight and obesity, it is necessary to test the respective values in a different coorte of children. Conclusion Age and gender specific reference curves of WC for Brazilian children and cut-off values for obesity risk may be used for national screening and interventional studies to reduce the obesity burden in Brazil. Author contributions Conception and design of the research: Santos JLF, Consolim F; Acquisition of data: Valério VP, Fernandes RN, Duarte L, Assumpção AC, Guerreiro J, Sickler AL, Lemos AAR, Goulart Filho JG; Analysis and interpretation of the data: Hussid MF, Camacho C, Sangaleti C, Consolim F; Statistical analysis: Camacho C; Writing of the manuscript: Camacho C, Sangaleti C, Consolim F; Critical revision of the manuscript for intellectual content: Santos JLF, Valério VP, Fernandes RN, Cesar LAM, Pinto IM, Magalhães C, Sangaleti C, Consolim F. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This study is not associatedwith any thesis or dissertationwork. Ethics approval and consent to participate This article does not contain any studies with human participants or animals performed by any of the authors. 535