Percentiles of waist-hip ratio and the relationship with blood pressure among children and adolescents in Shandong, China.

BACKGROUND: Anthropometric indices such as waist circumference (WC), waist-to-height ratio (WHtR) and waist-hip ratio (WHR) have been recognized as useful alternatives to visceral fat measurement in epidemiological studies. WHR has been used extensively in adults. However, there are very few published data for WHR among children and adolescents.

AIM: The present study examined the distribution of WHR and the relationship with blood pressure (BP) among children and adolescents in Shandong, PR China.

SUBJECTS AND METHODS: Data for this study were obtained from a large cross-sectional survey of schoolchildren carried out in 2010. A total of 38,822 students (19,456 boys and 19,366 girls) aged 7-17 years participated in this study. WC, Hip circumference (HC), systolic blood pressure (SBP) and diastolic blood pressure (DBP) of all subjects were measured; WHR was calculated as WC divided by HC. Abdominal obesity was defined by previously published WHR references based on Chinese children and adolescents living in Beijing. All subjects were divided into two groups (group 1 with WHR <85th; group 2 with WHR ≥85th) according to the percentiles of WHR and comparisons of the SBP and DBP between the two groups were made.

RESULTS: The WHR levels in Shandong boys and girls were lower than those from German and Pakistani. The overall prevalence of abdominal obesity was 9.53% (95% CI = 9.12-9.95%) for boys and 9.82% (95% CI = 9.40-10.24%) for girls, no statistical differences between the two genders were observed (p > 0.05). In both boys and girls, the Z-scores of SBP and DBP were all significantly lower in group 1 than in group 2 (p < 0.01), indicating that children and adolescents with high WHR tended to have higher BP values.

CONCLUSION: WHR is useful in identifying children and adolescents at risk of developing high BP. These findings, together with the known tracking of BP from adolescence into adulthood, highlight the importance of preventing overweight and obesity among children and adolescents in order to prevent the development of hypertension in adults.