title: Association of serum alanine aminotransferase and γ-glutamyltransferase levels within the reference range with metabolic syndrome and nonalcoholic fatty liver disease.
abstract: OBJECTIVE
  Nonalcoholic fatty liver disease (NAFLD) has recently been found to be a novel component of metabolic syndrome (MS), which is one of the leading causes of chronic liver disease. The serum alanine aminotransferase (ALT) and ⟨-glutamyltransferase (GGT) levels are suggested to affect liver fat accumulation and insulin resistance. We assessed the associations of serum ALT and GGT concentrations within the reference ranges with MS and NAFLD.
  
  
  METHODS
  In total, 1,069 subjects enrolled at the health promotion center of Wonkwang University Hospital were divided into 4 groups according to serum ALT and GGT concentrations levels within the reference ranges. We performed biochemical tests, including liver function tests and lipid profiles, and diagnosed fatty liver by ultrasonography. Associations of ALT and GGT concentrationgrading within the reference range with fatty liver and/or MS were investigated.
  
  
  RESULTS
  The presence of MS, its components, and the number of metabolic abnormalities [except for high-density lipoprotein-cholesterol (HDL-C) and fasting blood glucose] increased with the ALT level, while the presence of MS, its components, and the number of metabolic abnormalities (except for HDL-C) increased with the GGT level. The odds ratios for fatty liver and MS increased with the ALT level (P⟨0.001 and P=0.049, respectively) and the GGT level (P=0.044 and P=0.039, respectively).
  
  
  CONCLUSIONS
  Serum ALT and GGT concentrations within the reference ranges correlated with the incidence of NAFLD and MS in a dose-dependent manner. There associations need to be confirmed in large, prospective studies.
authors.affiliation: Department of Internal Medicine, Sanbon Medical Center, Wonkwang University College of Medicine, Gunpo, Korea.
authors.forename: Hyo Jeong
authors.initials: HJ
authors.lastname: Oh
authors.forename: Tae Hyeon
authors.initials: TH
authors.lastname: Kim
authors.forename: Young Woo
authors.initials: YW
authors.lastname: Sohn
authors.forename: Yong Sung
authors.initials: YS
authors.lastname: Kim
authors.forename: Yong Reol
authors.initials: YR
authors.lastname: Oh
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Cho
authors.forename: So Yeon
authors.initials: SY
authors.lastname: Shim
authors.forename: Sae Ron
authors.initials: SR
authors.lastname: Shin
authors.forename: A Lum
authors.initials: AL
authors.lastname: Han
authors.forename: Seok Jin
authors.initials: SJ
authors.lastname: Yoon
authors.forename: Haak Cheoul
authors.initials: HC
authors.lastname: Kim
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood*; D008076:Cholesterol, HDL / Q000097:blood; D005234:Fatty Liver / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000201:enzymology; D005260:Female; D006801:Humans; D008111:Liver Function Tests; D008297:Male; D024821:Metabolic Syndrome / Q000175:diagnosis* / Q000201:enzymology; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease; D016017:Odds Ratio; D012016:Reference Values; D012189:Retrospective Studies; D014463:Ultrasonography; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D008076:Cholesterol, HDL; D005723:gamma-Glutamyltransferase; D000410:Alanine Transaminase