OBJECTIVES: Overweight in children is most commonly described by using BMI. Because BMI does not adequately describe regional (central) adiposity, other indices of body fatness are being explored. Neck circumference (NC) is positively associated with obstructive sleep apnea, diabetes, and hypertension in adults. NC also has positive correlation with BMI in adults. The possible role of NC in screening for high BMI in children is not well characterized. The aims of this investigation were to examine the correlation between BMI and NC in children and to determine the best NC cutoff that identifies children with high BMI.
METHODS: Children who were aged 6 to 18 years and undergoing elective noncardiac surgeries were the subjects of this study. Trained research assistants collected clinical and anthropometric data from all patients. We calculated Pearson correlation coefficients between NC and other indices of obesity. We then determined by receiver operating characteristic analyses the optimal NC cutoff for identifying children with high BMI.
RESULTS: Among 1102 children, 52% were male. NC was significantly correlated with age, BMI, and waist circumference in both boys and girls, although the correlation was stronger in older children. Optimal NC cutoff indicative of high BMI in boys ranged from 28.5 to 39.0 cm. Corresponding values in girls ranged from 27.0 to 34.6 cm.
CONCLUSIONS: NC is significantly correlated with indices of adiposity and can reliably identify children with high BMI. NC is a simple technique that has good interrater reliability and could be used to screen for overweight and obesity in children.