Determination of the BMI threshold that predicts cardiovascular risk and insulin resistance in late childhood.

Abstract

AIMS: Body mass index (BMI, kg/m(2)) thresholds of children predicting cardiovascular risk, reported in previous studies were inconsistent and that predicting increased insulin resistance is lacking. We determined the BMI threshold that predicts increased cardiovascular risk and insulin resistance in children.

METHODS: The entire 4th grade students (187 boys and 218 girls) from 5 schools were included. Cardiovascular risk was defined as the presence of three or more of cardiovascular risk factors. Increased insulin resistance was estimated using homeostasis model assessment of insulin resistance and fasting insulin level.

RESULTS: The BMI percentile predicting cardiovascular risk was the 71.3th percentile for boys and the 77.1th percentile for girls. The BMI value was 21.4 kg/m(2) for boys and 20.6 kg/m(2) for girls. 34% of boys and 42% of girls with a BMI above the cut-off values had cardiovascular risk. The BMI percentile predicting increased insulin resistance was the 66.3th percentile for boys and the 67.9th percentile for girls. The children with cardiovascular risk had significantly greater (P<0.01) insulin resistance than those without risk.

CONCLUSION: This study demonstrated that the BMI thresholds at which cardiovascular risk and insulin resistance begin to increase in Korean children were lower than current definition of childhood obesity, proposed by the international obesity task force.