Early adiposity rebound is associated with metabolic risk in 7-year-old children.

BACKGROUND

Early adiposity rebound (AR <5 years) has been consistently associated with increased obesity risk, but its relationship with metabolic markers is less clear; in addition, the biologic mechanisms involved in these associations have not been established.

OBJECTIVE

The objective of this study was to assess the association between timing of AR and metabolic status at age 7 years, evaluating the potential role of adiposity, adipose functionality and skeletal maturation in this association.

DESIGN

We estimated the age of AR from the body mass index (BMI) trajectories from 0 to 7 years in 910 children from the Growth and Obesity Chilean Cohort Study (GOCS). At 7 years, we measured waist circumference (WC) and blood glucose, insulin, triglycerides and high-density lipoprotein-cholesterol levels and constructed a metabolic risk score. We also measured percent fat mass (adiposity), plasma concentrations of leptin and adiponectin (adipose functionality) and bone age using wrist ultrasound (skeletal maturation).

RESULTS

We found that 44% of the children had an AR <5 years. Earlier AR was associated with larger WC (β: 5.10 (95% confidence interval (CI): 4.29-5.91)), higher glucose (β: 1.02 (1.00-1.03)), insulin resistance (β Homeostatic Model Assessment: 1.06 (1.03-1.09)), triglycerides (β: 10.37 (4.01-6.73)) and adverse metabolic score (β: 0.30 (0.02-0.37)). Associations decreased significantly if adiposity was added to the models (i.e. β WC: 0.85 (0.33-1.38)) and, to a lesser extent, when adipokines (i.e. β WC: 0.73 (0.14-1.32)) and skeletal maturation (i.e. β WC: 0.65 (0.10-1.20)) were added.

CONCLUSION

In GOCS children, AR at a younger age predicts higher metabolic risk at 7 years; these associations are mostly explained by increased adiposity, but adipose dysfunction and accelerated skeletal maturation also have a role.