title: Relationship of vitamin D with insulin resistance and disease severity in non-alcoholic steatohepatitis.
abstract: OBJECTIVE
  The role of plasma vitamin D deficiency in the development of non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) remains poorly understood. Previous studies have suggested a role for vitamin D deficiency in the pathogenesis of NAFLD/NASH, but they have been rather small, and/or NAFLD was diagnosed using only aminotransferases or liver ultrasound. This study aimed to assess the role of vitamin D deficiency in relationship to liver fat accumulation and severity of NASH.
  
  
  METHODS
  A total of 239 patients were recruited and state-of-the-art techniques were used to measure insulin resistance (euglycemic insulin clamp with 3-(3)H-glucose), liver fat accumulation (magnetic resonance spectroscopy or (1)H-MRS), total body fat (dual energy X-ray absorptiometry), and severity of liver disease (liver biopsy).
  
  
  RESULTS
  Patients were divided into 3 groups according to plasma 25-hydroxyvitamin D levels (normal: >30 ng/ml; insufficiency: 20-30 ng/ml; deficiency: <20 ng/ml). When well-matched for clinical parameters (BMI, total adiposity, or prevalence of prediabetes/type 2 diabetes), no significant differences were observed among groups in terms of skeletal muscle, hepatic, or adipose tissue insulin sensitivity, the amount of liver fat by (1)H-MRS, or the severity of histological inflammation, ballooning, or fibrosis. Patients were then divided according to liver histology into those with definite NASH and those without NASH. Although patients with NASH had higher insulin resistance, plasma vitamin D concentrations were similar between both groups.
  
  
  CONCLUSIONS
  Our results suggest that plasma vitamin D levels are not associated with insulin resistance, the amount of liver fat accumulation, or the severity of NASH.
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA; Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA.
authors.forename: Fernando
authors.initials: F
authors.lastname: Bril
authors.affiliation: Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA; Division of Pediatric Gastroenterology, Hepatology and Nutrition, University of Florida, Gainesville, FL, USA.
authors.forename: Maryann
authors.initials: M
authors.lastname: Maximos
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA; Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA.
authors.forename: Paola
authors.initials: P
authors.lastname: Portillo-Sanchez
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA; Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA.
authors.forename: Diane
authors.initials: D
authors.lastname: Biernacki
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA; Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA.
authors.forename: Romina
authors.initials: R
authors.lastname: Lomonaco
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA; Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA.
authors.forename: Sreevidya
authors.initials: S
authors.lastname: Subbarayan
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Correa
authors.affiliation: Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA; Division of Internal Medicine, University of Florida, Gainesville, FL, USA.
authors.forename: Margaret
authors.initials: M
authors.lastname: Lo
authors.affiliation: Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA.
authors.forename: Amitabh
authors.initials: A
authors.lastname: Suman
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA; Malcom Randall Veterans Administration Medical Center (VAMC), Gainesville, FL, USA; Division of Diabetes, University of Texas Health Science Center at San Antonio (UTHSCSA), USA; Audie L. Murphy Veterans Administration Medical Center (VAMC), San Antonio, TX, USA. Electronic address: Kenneth.Cusi@medicine.ufl.edu.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Cusi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D001786:Blood Glucose / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007333:Insulin Resistance; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism*; D011379:Prognosis; D012720:Severity of Illness Index; D014807:Vitamin D / Q000378:metabolism*; D014808:Vitamin D Deficiency / Q000150:complications / Q000175:diagnosis / Q000378:metabolism*; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D014807:Vitamin D
keywords: Diabetes; Fatty liver; Hepatic steatosis; Hydroxyvitamin D; NAFLD; NASH; Obesity