Waist circumference percentiles in children and adolescents between 6 and 14 years from Santiago, Chile.

Objective: To describe the percentile distribution of waist circumference (WC) by sex and age in a representative sample of children and adolescents of lower-middle and low socioeconomic status in Santiago, Chile.

Methods: A cross-section of 3022 primary-school students between the ages of 6 and 14 from middle-low and low-class schools of Santiago. Ten schools from the Primary Education Society (SIP) in Santiago, Chile, were selected at random. WC was measured under standardized procedures as instructed by the WHO (midpoint between lower costal margin and iliac crest). The population was categorized between percentiles 10 and 90 and divided by sex and age.

Results: WC tends to increase with age in both males and females, but no significant differences were found in the percentiles by age for boys and girls at any age range (p>0.05). In our sample, comparing Chilean children with other populations (British, Australian, European-American, African-American, Mexican - American and Colombian), Chilean children have shown a significantly greater WC (p<0.05).

Conclusions: We present new WC reference values for Chilean children according to sex and age from a representative sample of Chilean population. These can be considered as a new anthropometric assessment tool for estimating cardiometabolic risk in Chilean children.