Association between blood pressure, body mass index, eating habits, and physical activity in adolescents

Aims: This study sought to analyze blood pressure and its association with eating behavior, physical activity, and body mass index in high school students.Methods: A cross-sectional study was performed with high school students from midwestern Brazil. Blood pressure was measured according to the guidelines outlined by the Brazilian Society of Cardiology. Nutritional status was assessed in accordance with the Brazilian Food and Nutrition Surveillance System (Sistema de Vigilância Alimentar Nutricional, SISVAN), according to the standard reference of the National Health and Nutritional Examination Survey (NHANES II), and the level of physical activity was assessed by the International Physical Activity Questionnaire-Short Form. The chi-square test and the Mann-Whitney U test were used for characterization of the population and comparisons between genders and normotensive and prehypertensive subjects. Bivariate and multivariate regression analyses were performed to verify the relationship between blood pressure, physical activity, and eating behavior. The significance level was set at p<0.05.Results: Prehypertension was detected in 26% of the students and overweight frequency was higher than the national average (38% for girls and 20% for boys). Concerning eating behavior, students’ nutritional habits were "very good" in 7%, "regular" in 68%, and "poor" in 24%. In bivariate analyses, systolic blood pressure and blood pressure percentile were positively associated with body mass index. In multivariate analyses, there were positive associations between eating behavior and body mass index with diastolic blood pressure: when body mass index was high and the eating behavior score was low (unhealthy eating habits), diastolic blood pressure was high. No relationship was observed between blood pressure and physical activity.Conclusions: The adolescents assessed in this study showed a high frequency of prehypertension. Body mass index was positively associated with high blood pressure, indicating that a high body mass index is a risk factor for the development of hypertension among adolescents. Therefore, early intervention to control body mass index may be a valuable strategy to prevent overweight, obesity, and hypertension.