ESPE Abstracts

Background: We previously reported that children with an earlier adiposity rebound (AR), which is defined as the time at which the BMI starts to rise after infancy, have a higher BMI and a greater atherogenic metabolic status at age 12. In addition, it has been reported that higher levels of leptin at age 3 is associated with greater weight gain and adiposity by age 7. This finding suggests that leptin resistance may begin in early childhood, even before age 3.

Objective and hypotheses: To investigate if early onset AR is related to the acquisition of leptin resistance at age 12.

Method: A total of 296 children (157 boys and 139 girls) in one Japanese community were enrolled in the study. 271 children were able to define the age of AR and were divided into six groups according to AR age: ≤age 2, 3, 4, 5, 6, and ≥7. Leptin levels were measured at age 12. The association between age at AR and leptin levels were examined.

Results: Geometric mean leptin levels in 12-year-old children were 3.3±1.6 and 5.2±1.5 ng/ml (boys and girls respectively) in non-obese children, 6.5±1.5 and 6.8±1.2 ng/ml in light obese subjects, 8.5±1.6 and 13.2±1.6 ng/ml in moderately obese subjects, and 20.1±1.3 and 20.9±1.3 ng/ml in severely obese subjects. An earlier AR was associated with higher level of leptin at age 12.

Conclusion: An earlier AR was associated with higher leptin levels at age 12, regardless of gender, suggesting that the timing of AR is an important factor that can predict leptin resistance in the future. Therefore, we propose that age of AR should be considered in early childhood to identify children at high risk for leptin resistance.