Original Research Article The Association Between Cardiovascular Risk Factors and High Blood Pressure in Adolescents: A School-Based Study DIEGO G.D. CHRISTOFARO, 1 R ^ OMULO A. FERNANDES, 1 ARLI R. OLIVEIRA, 2 ISMAEL FORTE FREITAS J  UNIOR, 1 MAURO V.G. BARROS, 3 AND RAPHAEL M. RITTI-DIAS 3 * 1 Laboratory of Investigation in Exercise – LIVE, Department of Physical Education, Universidade Estadual Paulista (UNESP), Presidente Prudente, Brazil 2 Department of Physical Education, Universidade Estadual de Londrina (UEL), Londrina, Brazil 3 Associate Graduate Program in Physical Education, Universidade de Pernambuco (UPE), Recife-PE, Brazil ABSTRACT: Objective: Although previous studies have analyzed the association between cardiovascular risk fac- tors and blood pressure in adolescents, few studies conducted in developing countries analyzed whether the aggrega- tion of risk factors contributes to an increased risk of high blood pressure in adolescents. The objective of this study was to assess the association between cardiovascular risk factors (including general overweight, abdominal obesity, high consumption of foods rich in fats, and insufficient physical activity levels) and high blood pressure in adolescents. Methods: This study was carried out from 2007 to 2008 with 1021 adolescents (528 girls) from primary schools located in the city of Londrina- Brazil. Blood pressure was assessed using an oscillometric device. General overweight was obtained through body mass index, abdominal obesity was assessed using waist circumference, and the consump- tion of foods rich in fat and physical activity were assessed using a questionnaire. The sum of these risk factors was determined. Results: Adolescents with three or four aggregated risk factors were more likely to have higher values of systolic and diastolic blood pressure when compared with adolescents who did not have any cardiovascular risk factors (P 5 0.001 for both). Logistic regression indicated that groups of adolescents with 2 (OR5 2.46 [1.11–5.42]; P 5 0.026), 3 (OR5 4.97 [2.07–11.92]; P 5 0.001) or 4 risk factors (OR5 6.79 [2.24–19.9]; P 5 0.001) presented an increased likelihood of high blood pressure. Conclusions: The number of cardiovascular risk factors was found to be related to high blood pressure in adoles- cents. Am. J. Hum. Biol. 00:000–000, 2014. V C 2014 Wiley Periodicals, Inc. Chronic diseases account for 60% of the annual deaths worldwide (Guilbert, 2003; Kannel, 1990) and hyperten- sion is an important risk factor, with a high prevalence in the adult population (Fernandes and Zanesco, 2010; Yang et al., 2010). Hypertension also affects pediatric popula- tions (Chiolero et al., 2007; Falkner et al., 2010), which is of major concern as its development begins in childhood or adolescence and is known to persist into adulthood (Chen et al., 2005). Therefore, the identification of risk factors related to hypertension in early life is important for the prevention of this chronic disease condition. General and abdominal obesity, a sedentary lifestyle, and inadequate food intake have been considered the main risk factors for hypertension among pediatric popu- lations (Christofaro et al., 2009b; Sorof et al., 2004). Stud- ies have pointed out that a high-fat and usually high- sodium diet is associated with high blood pressure even in young populations (Vitolo et al., 2013; Yang et al., 2012). A sedentary lifestyle with a low level of physical activity may also contribute to the chances of young people having high blood pressure (Gaya et al., 2011; Kollias et al., 2009). However, few studies have aimed at investigating whether the aggregation of these risk factors could con- tribute to an increased risk of high blood pressure in ado- lescents, with the majority of these studies being conducted in developed countries (Alamian and Paradis, 2009; Andersen et al., 2010; Berenson et al., 1998). Thus, the objective of this study was to assess the associ- ation between the sum of cardiovascular (CV) risk factors and high blood pressure in adolescents. We hypothesized that the risk of high blood pressure would be greater in subjects with a higher number of risk factors. METHODS Sample This study was carried out from 2007 to 2008 with ado- lescents from primary schools in Londrina— Brazil. Lon- drina is the third largest city in southern Brazil (510,000 inhabitants) and has approximately 70,000 students enrolled in elementary schools. For the purposes of establishing the sample, the city of Londrina was divided into five regions: the east, west, south, north, and central area. The number of students in both public and private schools in each region was taken into considera- tion for calculating the ratio of students to be selected for the sample, in order to maintain the proportionality of adolescents from both school systems in each region of the city. Two schools were randomly selected from each region, one public and one private. From drawings of these two schools, rooms were selected at random for eval- uation and, subsequently, the whole class was evaluated. A minimum sample size of 879 subjects was estimated considering; a prevalence of 10% for high blood pressure (Moura et al., 2004), an error of 3%, confidence interval of 95% (z 5 1.96), and power of 80%. After the fieldwork and exclusions due to refusal to participate, adolescents *Correspondence to: Raphael Mendes Ritti Dias, School of Physical Edu- cation, Pernambuco University, Rua Arn obio Marques, 310, Recife, PE 50100-130, Brazil. E-mail: raphaelritti@gmail.com Received 3 November 2013; Revision received 1 April 2014; Accepted 12 April 2014 DOI: 10.1002/ajhb.22555 Published online 00 Month 2014 in Wiley Online Library (wileyonlinelibrary.com). V C 2014 Wiley Periodicals, Inc. AMERICAN JOURNAL OF HUMAN BIOLOGY 00:00–00 (2014)