Is high waist circumference and body weight associated with high blood pressure in Iranian primary school children?

Abstract

The prevalence of overweight, abdominal obesity and hypertension among children has increased worldwide including Iran over several decades. We carried out a study to provide current estimates of the prevalence and trends of hypertension, overweight and obesity along with the relationship between weight status and hypertension in Iranian school-children. This study was carried out among 1184 fifth-grade students, whose ages ranged from 11 to 14years. Body weight, body mass index(BMI), height and waist circumference (WC), systolic (SBP) and diastolic blood pressure (DBP) were measured. 22.04 and 5.32% of students were overweight and obese, respectively. The prevalence of overweight and obesity was significantly higher among girls than boys (all p=0.02), whereas the prevalence of hypertension was significantly higher in boys than girls (p=0.001). Although 27% of boys and 24.32% of girls had abdominal obesity, no significant associations were reported between abdominal obesity and sex (p=0.12). The prevalence of hypertension in children with normal weight, overweight and obesity, was 3, 9.7 and 17.8%, respectively (p<0.01). We have obtained that the mean values of weight and WC were significantly higher in boys than girls. Based on linear regression, every 1cm increase in abdominal circumference leads to an estimated DBP and SBP increase of 0.173 and 0.164mmHg, respectively (p<0.05). This study showed a high prevalence of hypertension and obesity in a school-based population in Tehran, Iran, in which the prevalence of hypertension was significantly and positively correlated with weight and WC.