Objective: This study aimed to determine the optimal cutoff point of Waist-to-height (WHtR) for the diagnosis of metabolic syndrome (MS) in children and adolescents in six areas of China.
Methods: Ninety thousand two hundred and eighty four children aged 6 to 15 years old from 6 areas, including Beijing, Tianjin, Zhejiang, Shanghai, Chongqing and Nanning in China, were surveyed in a random cluster sample. Receiver operating characteristic (ROC) curve analysis was employed to determine the optimal cutoff values of WHtR for detecting the children and adolescents with two or more risk factors of MS.
Results: The optimal WHtR cutoff values derived from the ROC analysis was 85(th) and 80(th) percentiles in males and females, with 6-15 years of age, respectively. The sensitivity and specificity under these cutoff values were 35.78% and 85.41% in males and 49.21% and 79.87% in females, for 6-9 years of age, while the sensitivity and specificity were 49.60% and 85.90% in males and 47.01% and 80.07% in females for 10-15 years of age. The areas under the ROC curves (AUCs) for WHtR 85(th) percentile were 0.61 and 0.64 in males and females for 6-9 years of age, and 0.68 and 0.63 in males and females for 10-15 years of age. The AUCs for WHtR 85(th) percentile in both genders were significantly larger than that for WHtR 90(th) percentile for 10-15 years of age.
Conclusion: Our findings indicated that the 85(th) percentile of WHtR (0.48 in both genders for 6-9 years of age, 0.48 in males and 0.46 in females for 10-15 years of age) might be an appropriate cutoff to predict the children and adolescents with two or more risk factors.