Distribution curve of waist-to-height ratio and its association with blood pressure among children and adolescents: study in a large population in an eastern coastal province, China

Abstract

Several studies have suggested that waist-to-height ratio (WHtR) is an accurate and easier index for evaluating abdominal obesity in both children and adults. The present study examined the distribution of WHtR and its association with blood pressure (BP) levels among children and adolescents in a large population in Shandong, China. A total of 38,810 students (19,453 boys and 19,357 girls) aged 7-17 years participated in this study. Height, waist circumference (WC), and BP of all subjects were measured, and WHtR was calculated. Abdominal obesity was defined as WHtR ≥0.5; high BP status was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥95th percentile for age and gender. Overall, 16.45% (95%CI: 15.93-16.97) and 7.80% (95%CI: 7.42-8.17) of boys and girls had a WHtR ≥0.5. WHtR was positively correlated with SBP and DBP in both boys and girls. The mean values of SBP and DBP for both boys and girls were all significantly higher in the WHtR ≥0.5 group than in the WHtR<0.5 group. Z-scores of BP and the prevalence of high BP increased with WHtR. The prevalence of high BP increased from 10.61 (boys) and 9.64% (girls) in the WHtR <0.34 group to 55.11 (boys) and 51.97% (girls) in the WHtR ≥0.58 group, an increase of 4.2- and 4.4-times. We conclude that children and adolescents with high WHtR might have an increased risk of elevated BP. These findings highlight the importance of the prevention of abdominal obesity in order to prevent future-related problems such as hypertension in children and adolescents.