Fetuin-A and its relation to metabolic syndrome and fatty liver disease in obese children before and after weight loss.

CONTEXT: There are very limited data available concerning the relationships between fetuin-A, weight status, nonalcoholic fatty liver disease (NAFLD), and features of the metabolic syndrome (MetS) in obese humans, and especially in children.

OBJECTIVE

Our objective was to study the longitudinal relationships between fetuin-A, NAFLD, and MetS in obese children.

DESIGN

This was a 1-yr longitudinal follow-up study.

SETTING

This study was performed in primary care.

PATIENTS: A total of 36 obese and 14 lean children was included in the study.

INTERVENTION: An outpatient 1-yr intervention program based on exercise, behavior, and nutrition therapy was performed.

MAIN OUTCOME MEASURES: Changes of weight status (sd score-body mass index), waist circumference, fetuin-A, blood pressure, lipids, transaminases, insulin resistance index homeostasis model assessment (HOMA), and prevalence of NAFLD (defined by liver ultrasound) were calculated.

RESULTS

The 12 obese children with NAFLD had significantly higher fetuin-A levels (0.35+/-0.07 g/liter) than the 24 obese children without NAFLD (0.29+/-0.06 g/liter) and the 14 normal weight children (0.29+/-0.05 g/liter). Fetuin-A levels were independent of age, pubertal stage, and gender. Fetuin-A correlated significantly to systolic (r=0.50) and diastolic blood pressure (r=0.41), insulin resistance index HOMA (r=0.28), and high-density lipoprotein-cholesterol (r=-0.31). Changes of fetuin-A correlated significantly to changes of insulin resistance index HOMA (r=0.34), systolic (r=0.31) and diastolic blood pressure (r=0.37), and waist circumferences (r=0.36). Substantial weight loss in 21 children led to a significant decrease of fetuin-A and the prevalence of NAFLD in contrast to the 15 children without substantial weight loss.

CONCLUSIONS

Fetuin-A levels were higher in children with NAFLD, and were related to insulin resistance and to features of the MetS in both cross-sectional and longitudinal analyses. Therefore, fetuin-A might be a new promising link between obesity and its comorbidities.