Proposal of an indicator for overweight and obesity: weight-circumference waist index (WCWI)

Abstract

The objective is to evaluate the WCWI, to propose it as an indicator of overweight and obesity. It is a descriptive, prospective, cross-cutting and correlational study, in a sample of 896 children and adolescents aged 6 and 19; 452 (50.4%) 444 (49.6%) of the female sex. Methods: The variables sex, age, weight, size, BMI, BFP and WCWI were measured; averages, deviation, correlations and ROC curve were determined. Results: weight averages 43.1±14.8 kg; size 146.2±15.8 cm; BMI 19.6±3.6 kg/m2; WC 66.7±9.3 cm; WCWI 0.64±0.2 and BFP 15.5±7.3. Very good correlations between Size-Weight (0.87); Weight-BMI (0.84); WCWI-Weight (0.91); Size-WCWI (0.80) and BMI-WCWI (0.75); percentages resulting from classifying children and adolescents, according to BMI and WCWI values, and the three criteria assumed as references, indicate that: Overweight 10.9% (BMI) and 11.6% (WCWI); Obesity 5.3% (BMI) and 5.8% (WCWI); for the Mean and Deviation criterion, Overweight 4.1% (BMI) and 8.1% (WCWI); Obesity 0.3% (BMI) and 4.2% (WCWI). For the Fundacredesa criterion, Overweight 7.2% (BMI) and 8.0% (WCWI); Obesity 3.3% (BMI) and 3.6% (WCWI). Averages by sex, for non-significant weight, size, BMI, WC and WCWI variables; BFP averages (p<0.000). ROC curve moves away from the diagonal, coupled with the fact that the area under the curve is 0.983, reflects the goodness of the model, complemented by a high sensitivity and specificity, thus guaranteed a discriminating power. Conclusion: WCWI ROC curve, with area under the curve is 0.983, high sensibility and specificity, with discriminating capacity.