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

Abstract

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. Copyright © 2008 by The Endocrine Society.