Serum cardiovascular risk biomarkers in pre-pubertal obese children

BACKGROUND: Childhood obesity is associated with premature cardiovascular complications. However, little is known about the effect of a family-based behavioral intervention on the relationship between arterial function, blood pressure and biomarkers in pre-pubertal children with obesity. DESIGN: This was a single center randomized controlled trial (RCT) including 74 children randomized to a 6-month behavioral intervention to treat obesity. In 48 children (13 controls and 35 interventions), we assessed: serum level of cytokine (CCL2), adiponectin, and neutrophil product (MMP-8), as well as carotid intima-media thickness, flow-mediated dilation (FMD), nitroglycerin-mediated dilation; arterial stiffness (incremental elastic modulus, Einc), pulse wave velocity (PWV), resting and 24-hour blood pressure (BP). RESULTS: At baseline, resting systolic BP was positively associated with MMP-8 levels which was significantly higher in children with hypertension (p=0.033). Biochemical markers were not related to endothelial function at baseline, but they globally increased after 6 months in the intervention group. The significant increase of CCL2 levels in the intervention group was associated with a decrease in diastolic BP. Furthermore, adiponectin change was positively related to a change in FMD and negatively to change in Einc and PWV. CONCLUSIONS: The usefulness of serum biomarkers for the detection of cardiovascular diseases is not well established in children. In our population, MMP-8 concentration was higher in hypertensive children. Furthermore, behavioral interventions resulted in a paradoxical increase in some biomarkers in children, with potentially beneficial effects detected with CCL2 changes. Caution should be taken when using non-specific serum biomarkers for the clinical monitoring of children with obesity.