RESUMO
OBJECTIVE: The accumulation of abdominal fat is associated with cardiometabolic abnormalities. Waist circumference (WC) measurements allow an indirect evaluation of abdominal adiposity. However, controversy exists over which WC reference values are the most suitable for identifying the pediatric population at risk. The aim of the study was to evaluate the ability of various WC indices to identify abdominal obesity as diagnostic tools for predicting cardiometabolic risk in Mexican children and adolescents. METHODS: Anthropometric measurements were performed and biochemical profiles determined in a crosssectional study that included 366 children and adolescents. Four parameters were used to evaluate abdominal obesity in our study group: (1) WC >90th percentile, according to the Fernández reference in a Mexican-American population measured by the National Center for Health Statistics (NCHS) technique; (2) WC >90th percentile, according to the Klünder reference in a Mexican population (measured by the World Health Organization [WHO] technique); (3) waist-to-height ratio (WHtR) >0.5 according to WHO; and (4) WHtR >0.5 according to NCHS. The ability of each of the indices to discriminate cardiometabolic abnormalities (fasting plasma glucose, dyslipidemia, and hypertension) was assessed. RESULTS: WHtR >0.5 according to WHO or NCHS references showed greater sensitivity to detect metabolic abnormalities compared to percentile reference parameters (74.3 to 100% vs. 59.0 to 88.9%; P<.05). However, the percentiles displayed more specificity to identify these alterations (46.2 to 62.2 vs. 21.3 to 46.9; P<.05). Area under the curve analysis showed that WHtR >0.5 can more readily detect hypertriglyceridemia (0.642), hypoalphalipoproteinemia (0.700), and a combination of two or more metabolic abnormalities (0.661), whereas WC >90th percentile, according to Klünder, better detected hyperglycemia (0.555). CONCLUSION: WHtR >0.5 is a sensitive measure to identify pediatric patients with cardiometabolic alterations, despite its low specificity, and is a useful diagnostic tool to detect populations at risk. Based on the results of this study, we recommend preferential use of the Klünder waist circumference references over the Fernández method in Mexican pediatric populations. ABBREVIATIONS: AUC = area under the curve BMI = body mass index HDL = high-density lipoprotein IDF = International Diabetes Federation LDL = low-density lipoprotein MS = metabolic syndrome NCHS = National Center for Health Statistics ROC = receiver operating characteristic WC = waist circumference WHO = World Health Organization WHtR = waist-to-height ratio.
