Serum fetuin-A concentrations are elevated in subjects with impaired glucose tolerance and newly diagnosed type 2 diabetes.

OBJECTIVE: Hepatic steatosis is associated with an increased risk of diabetes. Although the levels of serum fetuin-A, a liver-derived glycoprotein that impairs insulin signalling, are positively correlated with hepatic steatosis, the levels of fetuin-A in subjects with impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and newly diagnosed type 2 diabetes (NDD) have not been established. The aim of this study is to investigate the relationship among serum fetuin-A concentrations, IFG, IGT and NDD in Chinese subjects without nonalcoholic fatty liver disease (NAFLD).
DESIGN: A total of 360 age- and sex-matched subjects with normal glucose tolerance (NGT), IFG, IGT and NDD were recruited in this case-control study. MEASUREMENTS: Each subject was assessed by abdominal ultrasound to exclude the presence of NAFLD. Serum fetuin-A concentrations were measured by enzyme-linked immunosorbent assay and compared between NGT, IFG, IGT and NDD groups. The association with clinical and metabolic parameters was also examined.
RESULTS: Serum fetuin-A concentrations were higher in NDD and IGT groups than NGT groups (341 ± 88, 335 ± 90, and 300 ± 75 μg/ml). In multiple linear regression analysis, IGT (P < 0·01) and NDD (P < 0·05) were the positively associated factors of serum fetuin-A concentrations, but age (P < 0·05) was a negatively associated factor after adjusting for age, anthropometric indices, lipid profile, estimated glomerular filtration rate (eGFR), adiponectin, C-reactive protein (CRP) and homeostasis model assessment (HOMA-IR).
CONCLUSIONS: IGT and NDD are positively associated with serum fetuin-A concentrations in subjects without NAFLD independent of cardiometabolic risk factors.