title: Preferential fat deposition in subcutaneous versus visceral depots is associated with insulin sensitivity.
abstract: BACKGROUND
  Studies on the relationship between regional fat and insulin resistance yield mixed results. Our objective was to determine whether regional fat distribution, independent of obesity, is associated with insulin resistance.
  
  
  METHODS
  Subjects included 115 healthy, overweight/moderately obese adults with body mass index (BMI) 25-36.9 kg/m(2) who met predetermined criteria for being insulin resistant (IR) or insulin sensitive (IS) based on the modified insulin suppression test. Computerized tomography was used to quantify visceral adipose tissue (VAT), sc adipose tissue (SAT), and thigh adipose tissue. Fat mass in each depot was compared according to IR/IS group, adjusting for BMI and sex.
  
  
  RESULTS
  Despite nearly identical mean BMI in the IR vs. IS groups, VAT and %VAT were significantly higher in the IR group, whereas SAT, %SAT, and thigh sc fat were significantly lower. In logistic regression analysis, each sd increase in VAT increased the odds of being IR by 80%, whereas each increase in SAT decreased the odds by 48%; each increase in thigh fat decreased the odds by 59% and retained significance after adjusting for other depots. When grouped by VAT tertile, IS vs. IR individuals had significantly more SAT. There was no statistically significant interaction between sex and these relationships.
  
  
  CONCLUSIONS
  These data demonstrate that after adjustment for BMI and VAT mass, sc abdominal and thigh fat are protective for insulin resistance, whereas VAT, after adjustment for SAT and BMI, has the opposite effect. Whether causal in nature or a marker of underlying pathology, these results clarify that regional distribution of fat-favoring sc depots is associated with lower risk for insulin resistance.
authors.affiliation: Division of Endocrinology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305-5103, USA. tmclaugh@stanford.edu
authors.forename: Tracey
authors.initials: T
authors.lastname: McLaughlin
authors.forename: Cindy
authors.initials: C
authors.lastname: Lamendola
authors.forename: Alice
authors.initials: A
authors.lastname: Liu
authors.forename: Fahim
authors.initials: F
authors.lastname: Abbasi
mesh_terms: D050154:Adiposity / Q000502:physiology*; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D050152:Intra-Abdominal Fat / Q000000981:diagnostic imaging / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000000981:diagnostic imaging / Q000378:metabolism*; D011859:Radiography; D012737:Sex Factors; D050151:Subcutaneous Fat / Q000000981:diagnostic imaging / Q000378:metabolism*