Body mass index is important determinant of blood pressure in adolescents

Obesity is an important risk factor for development of hypertension. We investigated the association between body mass index (BMI) and blood pressure in adolescents. The cross-sectional study was performed on 694 adolescents aged 12-18 years from middle and high schools located in 4 districts of Shiraz, Iran. Height, weight, and systolic and diastolic blood pressures were measured according to standard procedures. The prevalence of overweight/obesity and elevated systolic and diastolic blood pressure was 22.0%, 16.8%, and 13.3%, respectively. Compared to girls, boys had higher rates of overweight/obesity and elevated blood pressure. With increasing age, the prevalence of overweight decreased (20.6% in 15-18 years compared to 34.3% in 12-14 years) and that of elevated blood pressure increased (33.2% vs.14.6% for systolic and 22.2% vs. 10.3% for diastolic blood pressure) in boys whereas the prevalence of overweight/obesity and elevated blood pressure did not change among girls. In both sexes, elevated blood pressure had a positive association with BMI categories independent of age and this association was observed even in normal versus low BMI categories. A strong association between BMI and elevated blood pressure advocates using strategies for the control of weight and prevention of obesity in adolescents.