title: Identification of novel clinical factors associated with hepatic fat accumulation in extreme obesity.
abstract: OBJECTIVE
  The accumulation of lipids stored as excess triglycerides in the liver (steatosis) is highly prevalent in obesity and has been associated with several clinical characteristics, but most studies have been based on relatively small sample sizes using a limited set of variables. We sought to identify clinical factors associated with liver fat accumulation in a large cohort of patients with extreme obesity.
  
  
  METHODS
  We analyzed 2929 patients undergoing intraoperative liver biopsy during a primary bariatric surgery. Univariate and multivariate regression modeling was used to identify associations with over 200 clinical variables with the presence of any fat in the liver and with moderate to severe versus mild fat accumulation.
  
  
  RESULTS
  A total of 19 data elements were associated with the presence of liver fat and 11 with severity of liver fat including ALT and AST, plasma lipid, glucose, and iron metabolism variables, several medications and laboratory measures, and sleep apnea. The accuracy of a multiple logistic regression model for presence of liver fat was 81% and for severity of liver fat accumulation was 77%.
  
  
  CONCLUSIONS
  A limited set of clinical factors can be used to model hepatic fat accumulation with moderate accuracy and may provide potential mechanistic insights in the setting of extreme obesity.
authors.affiliation: Department of Medical Genetics and Molecular Biochemistry, Temple University School of Medicine, 3500 N. Broad Street, Philadelphia, PA 19140, USA.
authors.forename: Glenn S
authors.initials: GS
authors.lastname: Gerhard
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Benotti
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: G Craig
authors.identifier: 0000-0002-6015-9692
authors.initials: GC
authors.lastname: Wood
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Chu
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: George
authors.identifier: 0000-0002-3675-2138
authors.initials: G
authors.lastname: Argyropoulos
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: Anthony
authors.identifier: 0000-0002-5072-9161
authors.initials: A
authors.lastname: Petrick
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: William E
authors.initials: WE
authors.lastname: Strodel
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: Jon D
authors.initials: JD
authors.lastname: Gabrielsen
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Ibele
authors.affiliation: Geisinger Obesity Research Institute, Danville, PA 17822, USA.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Still
authors.affiliation: Translational Genomics Institute, Phoenix, AZ 85004, USA.
authors.forename: Christopher
authors.identifier: 0000-0002-7158-4563
authors.initials: C
authors.lastname: Kingsley
authors.affiliation: Translational Genomics Institute, Phoenix, AZ 85004, USA.
authors.forename: Johanna
authors.identifier: 0000-0002-3286-0270
authors.initials: J
authors.lastname: DiStefano
mesh_terms: D050110:Bariatric Surgery; D015415:Biomarkers / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D005234:Fatty Liver / Q000209:etiology / Q000378:metabolism*; D005260:Female; D006801:Humans; D007501:Iron / Q000378:metabolism; D008055:Lipids / Q000097:blood; D008099:Liver / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000150:complications* / Q000378:metabolism / Q000601:surgery; D012720:Severity of Illness Index; D012891:Sleep Apnea Syndromes / Q000150:complications; D014280:Triglycerides / Q000378:metabolism
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D008055:Lipids; D014280:Triglycerides; D007501:Iron