CUT OFF VALUES FOR WAIST CIRCUMFERENCE TO PREDICT OVERWEIGHT IN BRAZILIAN ADOLESCENTS, ACCORDING TO PUBERTAL STAGING

To establish waist circumference cut off points according to pubertal staging to identify overweight in adolescents.

Longitudinal study approved by the Ethics Research Committee and conducted with 557 adolescents, aged 10 to 15 years old, selected from public schools. Waist, arm, neck and hip circumferences, body fat percentage, body mass index (BMI), height and blood pressure were measured. Pubertal staging was evaluated by Tanner self assessment scale. The Receiver Operating Characteristic Curve (ROC curve) was used to determine predictive power, sensitivity, specificity and waist circumference cut off points to detect overweight.

There was a positive correlation between waist circumference and weight, BMI, upper arm and hip circumferences, waist-to-hip ratio and blood pressure in both sexes. Cut off points for waist circumference according to pubertal stage as related to overweight in adolescents with the best performances in ROC curve were: 71.65 cm for prepubescent girls, 67.90 cm for pubescent girls, 70.25 cm for post pubescent girls, and 66.45 cm for pubescent boys. Age, weight, height, BMI, body fat percentage, arm and hip circumferences were associated to altered waist circumference.

The establishment of cut off points for waist circumference according to pubertal staging was proven a good means to identify overweight. These cut off points can be considered reliable for the Brazilian adolescent population, as the isolated use of chronological age in adolescents may underestimate their nutritional status.