The relationship of body mass index distribution to relatively high blood pressure among children and adolescents in Shandong, China

BACKGROUND: Obesity and hypertension are both common health problems in children and adolescents; several studies have reported that obesity is associated with elevated blood pressure (BP) in both adults and children. However, no studies on the association between body mass index (BMI) distribution and prevalence of relatively high BP among children and adolescents have been reported in China. AIM: The present study examined the relationship of BMI distribution to relatively high BP among children and adolescents in Shandong, China. SUBJECTS AND METHODS: A total of 8568 students (4,333 boys and 4,235 girls) aged 7-18 years participated in this study. Height, weight and BP of all subjects were measured; BMI of adolescents was calculated from their height and weight. Relatively high BP status was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥ 95th percentile for age and gender. Prevalence of relatively high BP within each BMI percentile category was determined. Comparisons of BP among different BMI percentile groups were made. RESULTS: The levels of SBP and DBP increased with age and were positively correlated with BMI in both boys and girls. The overall prevalence of relatively high BP was 24.07% for boys and 22.36% for girls. Prevalence of relatively high BP increased with BMI percentiles, this trend being especially obvious in the upper percentiles of BMI. An increasing trend was observed in SBP and DBP from BMI < 25th, 25th ≤ BMI < 50th, 50th ≤ BMI < 75th to BMI ≥ 75th percentile group. CONCLUSION: There is a high prevalence of relatively high BP among children and adolescents in Shandong, China. The present findings emphasize the importance of prevention of overweight and obesity in order to prevent future related problems such as hypertension in children and adolescents.