Waist-to-height ratio as an index for cardiometabolic risk in adolescents: Results from the 1998−2008 KNHANES

Purpose: To describe the relationship between the waist-to-height ratio (WHtR) and cardiometabolic risk factors (CMRFs) and to evaluate the validity of WHtR in identifying adolescents with metabolic syndrome. Materials and Methods: We analyzed data from a pooled population of 4068 adolescents aged 10–19 years from the Korean National Health and Nutrition Examination Surveys conducted between 1998 and 2008. Overweight individuals were defined by body mass index (BMI) ≥85th percentile. Those with at least 2 CMRFs among hypertension, hyperglycemia, hypertriglyceridemia, and decreased high-density lipoprotein cholesterol (HDL-C) were classified as having multiple CMRFs. Results: WHtR was significantly related to systolic blood pressure, HDL-C, and triglycerides in both non-overweight and overweight adolescents (all p<0.01). Among overweight adolescents, the area under the curve (AUC) for WHtR in identifying multiple CMRFs was significantly greater than that for BMI (p=0.014). Metabolic syndrome was more common in overweight adolescents with a WHtR of ≥0.5 than in those with a WHtR of <0.5 (p<0.001). In non-overweight adolescents, the prevalences of multiple CMRFs (p=0.001) and metabolic syndrome (p<0.001) were higher in those with a WHtR of ≥0.5 than in those with a WHtR of <0.5. Among those without central obesity, the prevalence of multiple CMRFs was higher in those with a WHtR of ≥0.5 than in those with a WHtR of <0.5 (p=0.021). Conclusion: WHtR is a simple and valid index for identifying adolescents with increased cardiometabolic risk and is related to CMRFs even in non-overweight adolescents. In adolescents already screened via BMI and waist circumference (WC), WHtR seems to be of additional help in discriminating those at higher cardiometabolic risk.