Evaluating <scp>WHtR</scp> and <scp>WC</scp> cut‐offs for abdominal obesity among children and adolescents: Insights from three National Surveys in China

AIM: To assess the application of current waist-to-height ratio (WHtR) and waist circumference (WC) evaluation criteria and identify preferred recommendations for public health practise. MATERIALS AND METHODS: Data were from three waves of the Chinese National Survey on Students Constitution and Health (CNSSCH) conducted in 2010, 2014 and 2019; abdominal obesity was classified using four WHtR and WC standards. Age- and sex-specific WHtR and WC percentile curves were generated using the LMS method. Prevalence of central adiposity by WHtR/WC and general obesity by BMI were compared. Predictive performance of the criteria was validated using an independent dataset with cardiometabolic risk factors. RESULTS: WHtR percentile curves showed a relatively flat trend with age in both sexes compared to WC curves. Abdominal obesity prevalence increased significantly from 2010 to 2019 across all criteria: international cut-off (0.46) (21.26%-27.66%), Chinese WC cut-offs (13.77%-19.64%), international WHtR cut-off (0.50) (9.12%-13.01%) and international WC cut-offs (7.95%-11.95%). All abdominal obesity criteria identified substantially more cases than BMI-based general obesity in 2019 (8.14%). The Chinese WC cut-offs showed superior predictive performance compared to the other three standards for cardiometabolic outcomes. CONCLUSIONS: The Chinese WC cut-offs and international cut-off (0.50) are optimal for childhood abdominal obesity screening in China due to their public health applicability. Standardized global criteria are urgently needed to enhance research comparability.