title: Incremental Predictive Value of Serum AST-to-ALT Ratio for Incident Metabolic Syndrome: The ARIRANG Study.
abstract: OBJECTIVE
  The ratio of aspartate aminotransferase (AST) to alanine aminotransferase (ALT) is of great interest as a possible novel marker of metabolic syndrome. However, longitudinal studies emphasizing the incremental predictive value of the AST-to-ALT ratio in diagnosing individuals at higher risk of developing metabolic syndrome are very scarce. Therefore, our study aimed to evaluate the AST-to-ALT ratio as an incremental predictor of new onset metabolic syndrome in a population-based cohort study.
  
  
  METHODS
  The population-based cohort study included 2276 adults (903 men and 1373 women) aged 40-70 years, who participated from 2005-2008 (baseline) without metabolic syndrome and were followed up from 2008-2011. Metabolic syndrome was defined according to the harmonized definition of metabolic syndrome. Serum concentrations of AST and ALT were determined by enzymatic methods.
  
  
  RESULTS
  During an average follow-up period of 2.6-years, 395 individuals (17.4%) developed metabolic syndrome. In a multivariable adjusted model, the odds ratio (95% confidence interval) for new onset of metabolic syndrome, comparing the fourth quartile to the first quartile of the AST-to-ALT ratio, was 0.598 (0.422-0.853). The AST-to-ALT ratio also improved the area under the receiver operating characteristic curve (AUC) for predicting new cases of metabolic syndrome (0.715 vs. 0.732, P = 0.004). The net reclassification improvement of prediction models including the AST-to-ALT ratio was 0.23 (95% CI: 0.124-0.337, P<0.001), and the integrated discrimination improvement was 0.0094 (95% CI: 0.0046-0.0143, P<0.001).
  
  
  CONCLUSIONS
  The AST-to-ALT ratio independently predicted the future development of metabolic syndrome and had incremental predictive value for incident metabolic syndrome.
authors: Department of Preventive Medicine, Yonsei University, Wonju College of Medicine, Wonju, Korea.
authors: Dhananjay
authors: D
authors: Yadav
authors: Institute of Lifestyle Medicine, Yonsei University, Wonju College of Medicine, Wonju, Korea.
authors: Eunhee
authors: http://orcid.org/0000-0002-3449-0672
authors: E
authors: Choi
authors: Department of Preventive Medicine, Yonsei University, Wonju College of Medicine, Wonju, Korea.|Institute of Genomic Cohort, Yonsei University, Wonju College of Medicine, Wonju, Korea.
authors: Song Vogue
authors: SV
authors: Ahn
authors: Department of Internal Medicine, Yonsei University, Wonju College of Medicine, Wonju, Korea.
authors: Soon Koo
authors: SK
authors: Baik
authors: Department of Internal Medicine, Yonsei University, Wonju College of Medicine, Wonju, Korea.
authors: Youn Zoo
authors: YZ
authors: Cho
authors: Department of Preventive Medicine, Yonsei University, Wonju College of Medicine, Wonju, Korea.
authors: Sang Baek
authors: SB
authors: Koh
authors: Department of Internal Medicine, Yonsei University, Wonju College of Medicine, Wonju, Korea.
authors: Ji Hye
authors: JH
authors: Huh
authors: Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, Korea.
authors: Yoosoo
authors: Y
authors: Chang
authors: Division of Cardiology, Department of Medicine, Kangbuk Samsumg Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors: Ki-Chul
authors: KC
authors: Sung
authors: Institute of Genomic Cohort, Yonsei University, Wonju College of Medicine, Wonju, Korea.|Department of Cardiology, Yonsei University, Wonju College of Medicine, Wonju, Korea.
authors: Jang Young
authors: JY
authors: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood*; D019540:Area Under Curve; D001219:Aspartate Aminotransferases / Q000097:blood*; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood*; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D056910:Republic of Korea; D012306:Risk
chemical_list: D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase