title: Association of serum gamma-glutamyltransferase and alanine aminotransferase activities with risk of type 2 diabetes mellitus independent of fatty liver.
abstract: BACKGROUND
  Although elevated serum concentrations of gamma-glutamyltrans- ferase (GGT) or alanine aminotransferase (ALT) have been associated with type 2 diabetes mellitus, it is unclear whether each is an independent predictor of type 2 diabetes or merely a surrogate marker for fatty liver or hepatic injury.
  
  
  METHODS
  We assessed clinical and laboratory findings in 3556 non-diabetic subjects (2217 men, 1339 women; age, 45.7 +/- 8.1 (range 20-79) years) without fatty liver or clinically significant hepatic dysfunction who underwent voluntary medical check-ups at a 5-year interval.
  
  
  RESULTS
  The odds ratio of developing type 2 diabetes increased significantly with increasing GGT and ALT levels at baseline. In multiple logistic regression models adjusted for age, sex, alcohol consumption, smoking, body mass index (BMI), triglycerides, high-density lipoprotein (HDL)-cholesterol, fasting glucose, and ALT, the highest quartile of GGT remained significantly associated with type 2 diabetes. Compared with the first GGT quartile, the odds ratios of the second, third, and fourth GGT quartiles were 0.64 (95% CI, 0.25-1.65), 1.12 (0.45-2.78), and 3.07 (1.21-7.76), respectively. The adjusted odds ratios for the second, third, and fourth ALT quartiles in the same logistic regression model were 2.40 (0.83-6.94), 2.85 (1.03-7.90), and 4.31 (1.56-11.88), respectively. The risk of type 2 diabetes was additive with respect to GGT and ALT quartiles.
  
  
  CONCLUSIONS
  Increased serum GGT and ALT levels are independent, additive risk factors for the development of type 2 diabetes mellitus in subjects without fatty liver or hepatic dysfunction.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon, Korea.
authors.forename: Chul-Hee
authors.initials: CH
authors.lastname: Kim
authors.forename: Joong-Yeol
authors.initials: JY
authors.lastname: Park
authors.forename: Ki-Up
authors.initials: KU
authors.lastname: Lee
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Kim
authors.forename: Hong-Kyu
authors.initials: HK
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood*; D001219:Aspartate Aminotransferases / Q000097:blood*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000453:epidemiology*; D005234:Fatty Liver / Q000097:blood* / Q000201:enzymology*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012016:Reference Values; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult
chemical_list: D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase