title: Intrahepatic lipid content is linked to insulin resistance in obese subjects.
abstract: CONCLUSIONS
  
  
  
  BACKGROUND
  Abdominal visceral fat (VAT) and intrahepatic lipid (IHL) are associated with insulin resistance in obese subjects, but VAT is usually measured on CT scans at the umbilical level or on MRI images of the partial abdomen. Thus, the association of the total abdominal visceral fat volume (VFV) with insulin resistance is unclear. In this study, we evaluated the correlations of obesity-related factors, including VFV and IHL, with clinical markers of insulin resistance (HOMA-R and the MATSUDA Index), and then assessed the effect of weight loss on these factors and markers.
  
  
  METHODS
  The study population consisted of 30 obese Japanese subjects with a BMI > 25 kg/m(2) (13 men and 17 women) who underwent a 75-g oral glucose tolerance test to calculate HOMA-R and the MATSUDA Index, dual energy X-ray absorptiometry (DEXA) for measurement of body fat (%-Fat), proton magnetic resonance spectroscopy ((1)H MRS) to assess IHL, and whole abdominal CT scanning (from the top of the liver to the floor of the pelvic cavity = about 700 slices) to determine the total abdominal subcutaneous fat volume (SFV) and VFV. Seven subjects from the original population were placed on a diet and exercise program, and these indices were examined again after 5% reduction of body weight.
  
  
  RESULTS
  Abdominal SFV, VFV, and IHL were mutually independent, but BMI and %-Fat were not independent of the other factors. According to multiple regression analysis, IHL (but not SFV or VFV) was significantly correlated with both HOMA-R and the MATSUDA Index in obese patients. Weight reduction by 5% led to improvement of the MATSUDA Index and decreased the number of subjects with metabolic syndrome, and the reduction of IHL was greater than that of SFV or VFV. These results suggest that IHL may be a superior marker of insulin resistance.
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Yukiyoshi
authors: Y
authors: Sada
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan. Electronic address:t2kataba@marianna-u.ac.jp.
authors: Takuyuki
authors: T
authors: Katabami
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Shiko
authors: S
authors: Asai
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Tomoko
authors: T
authors: Sato
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Kentarou
authors: K
authors: Furukawa
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Satoshi
authors: S
authors: Ishii
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Hiroyuki
authors: H
authors: Kato
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Hidetoshi
authors: H
authors: Kobayashi
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Akihiko
authors: A
authors: Kondo
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Akio
authors: A
authors: Ohta
authors: Department of Radiology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Yasuo
authors: Y
authors: Nakajima
authors: Department of Internal Medicine, Division of Metabolism and Endocrinology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
authors: Yasushi
authors: Y
authors: Tanaka