Waist circumference and body fat distribution indexes as screening tools for the overweight and obesity in Thai preschool children.

BACKGROUND

Evidence shows that waist circumference (WC) is one reliable index to predict abdominal obesity in children. This study aims to examine the relationship of WC to other anthropometric indexes and to determine the ability of WC as obesity screening tool.

SUBJECTS

811, 5-6 years old children in Saraburi province, central region of Thailand.

METHODS

Anthropometric measurements were performed in children; 406 boys and 405 girls. WC measurement was performed at the umbilicus level. Subcutaneous skinfold was measured on subscapular, suprailiac and abdominal regions. Total body fat was measured with bioelectrical impedance analyzer. Receiver operating characteristic (ROC) analysis was employed to determine WC cut-offs for predicting obesity in children.

RESULTS

WC highly correlated with weight-for-height Z-score (WHZ) (r = 0.92-0.94, p = 0.01), body mass index (BMI) (r = 0.95-0.96, p = 0.01), trunk skinfold (r = 0.92-0.93, p = 0.01) and total body fat (r = 0.94-0.95, p = 0.01) for both genders. Based on Thai national reference, the optimal WC cut-offs for predicting obesity were 59.6 cm for boys and 60.5 cm for girls. When IOTF-BMI was employed as reference, WC thresholds were 64.4 cm for boys and 63.1 cm for girls. The latter WC cut-offs provided the slightly underestimated obesity prevalence compared with national reference.

CONCLUSION

The strongly positive correlation between WC and weight-height based index and between WC and body fat in Thai preschool children suggests that WC should be the additional index for obesity screening in young children. Further study needs to explore the association between the increased WC and other adverse health outcomes.