Determination of central body fat by measuring natural waist and umbilical abdominal circumference in Guatemalan schoolchildren.

BACKGROUND: Obesity prevalence is rising in many developing countries, also among children. Waist circumference (WC) is a good measure of central obesity.

OBJECTIVES: Our aim was to compare umbilical waist circumference (UWC) and natural waist circumference (NWC) in children between socio-economic status (SES) and between sex; to describe correlations between body mass index (BMI), UWC and NWC; and to compare waist-to-height ratio (WHtR) between stunted and non-stunted children.

STUDY POPULATION AND METHODS: We measured height, weight and waist circumference at the natural and at the umbilical level in 583 boys and girls aged 8 to 10 years of two different social strata in Quetzaltenango, Guatemala.

RESULTS: Mean UWC and mean NWC (cm) were significantly larger in high SES than in low SES children (66.6 vs. 62.7, p<0.001, and 62.6 vs. 59.8, p<0.001, respectively). Boys had a larger mean NWC than girls (62.8 vs. 60.3, p<0.001). The mean difference between UWC and NWC (UWC-NWC) was larger in high SES and in boys. Overall, Pearson correlation of BMI vs. NWC is high (r=0.902, p<0.001), of BMI vs. UWC is higher (r=0.919, p<0.001) and of NWC vs. UWC is highest (r=0.965, p<0.001). The proportion of WHtR>/=0.500 was significantly higher in non-stunted than in stunted boys (p=0.03) and in high SES as compared with low SES children (p<0.001). Results for mean WHtR were not significant.

CONCLUSIONS: Based on these results, in Quetzaltenango high SES, non-stunted schoolchildren are most likely to have a centralized body fat pattern.