title: Hyperinsulinemia predicts hepatic fat content in healthy individuals with normal transaminase concentrations.
abstract: Although the prevalence of insulin resistance (IR) and compensatory hyperinsulinemia (CH) is increased in patients with nonalcoholic fatty liver disease, the role of IR/CH in regulation of hepatic fat content in healthy volunteers with normal concentrations of alanine transaminase (ALT) has not been defined. To address this issue, hepatic fat content was quantified by ultrasound in 69 (30 men, 39 women) healthy individuals, without known risk factors for liver disease and with plasma ALT concentrations of less than 30 U/L. Experimental variables quantified included body mass index, waist circumference, systolic and diastolic blood pressures, and fasting plasma glucose, fasting plasma insulin (FPI), and lipid concentrations. Subjects were classified as having no (55%), mild (27%), or moderate to severe (18%) hepatic steatosis on the basis of the ultrasound results. Statistically significant (P < .05-.001) correlations (Spearman rho values) existed between liver fat content and ALT (0.26), body mass index (0.52), waist circumference (0.50), systolic blood pressure (0.28), diastolic blood pressure (0.27), fasting plasma glucose (0.47), FPI (0.56), triglycerides (0.30), and high-density lipoprotein cholesterol (-0.35). Multivariate general discriminant analysis and multiple linear regression analysis indicated that FPI was the only independent predictor (P < .001) of both liver fat content and ALT concentrations. Fasting plasma insulin (a surrogate estimate of IR/CH) predicts hepatic fat content and ALT in healthy volunteers with normal transaminase concentrations, independently of the other anthropometric and metabolic variables measured.
authors.affiliation: Department of Internal Medicine and Biomedical Sciences, University of Parma, Parma 43100, Italy; Falk Cardiovascular Research Center, School of Medicine, Stanford University, Stanford, CA 94305, USA.
authors.forename: Diego
authors.initials: D
authors.lastname: Ardigò
authors.forename: Filippo
authors.initials: F
authors.lastname: Numeroso
authors.forename: Silvia
authors.initials: S
authors.lastname: Valtueña
authors.forename: Laura
authors.initials: L
authors.lastname: Franzini
authors.forename: Pier Marco
authors.initials: PM
authors.lastname: Piatti
authors.forename: Lucilla
authors.initials: L
authors.lastname: Monti
authors.forename: Roberto
authors.initials: R
authors.lastname: Delsignore
authors.forename: Gerald M
authors.initials: GM
authors.lastname: Reaven
authors.forename: Ivana
authors.initials: I
authors.lastname: Zavaroni
mesh_terms: D000368:Aged; D000410:Alanine Transaminase / Q000097:blood*; D005234:Fatty Liver / Q000209:etiology*; D005260:Female; D006801:Humans; D006946:Hyperinsulinism / Q000150:complications*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008099:Liver / Q000378:metabolism; D008297:Male; D008875:Middle Aged
chemical_list: D007328:Insulin; D000410:Alanine Transaminase