title: Visceral adiposity and risk of type 2 diabetes: a prospective study among Japanese Americans.
abstract: OBJECTIVE
  We conducted a prospective study among Japanese Americans of diabetes incidence in relation to visceral and regional adiposity, fasting insulin and C-peptide, and a measure of insulin secretion, because little prospective data exist on these associations.
  
  
  METHODS
  Baseline variables included plasma glucose, C-peptide, and insulin measured after an overnight fast and 30 and 120 min after a 75-g oral glucose tolerance test; abdominal, thoracic, and thigh fat areas by computed tomography (CT); BMI (kg/m2); and insulin secretion (incremental insulin response [IIR]).
  
  
  RESULTS
  Study subjects included 290 second-generation (nisei) and 230 third-generation (sansei) Japanese Americans without diabetes, of whom 65 and 13, respectively, developed diabetes. Among nisei, significant predictors of diabetes risk for a 1 SD increase in continuous variables included intra-abdominal fat area (IAFA) (odds ratio, 95% CI) (1.6, 1.1-2.3), fasting plasma C-peptide (1.4, 1.1-1.8), and the IIR (0.5, 0.3-0.9) after adjusting for age, sex, impaired glucose tolerance, family diabetes history, and CT-measured fat areas other than intra-abdominal. Intra-abdominal fat area remained a significant predictor of diabetes incidence even after adjustment for BMI, total body fat area, and subcutaneous fat area, although no measure of regional or total adiposity was related to development of diabetes. Among sansei, all adiposity measures were related to diabetes incidence, but, in adjusted models, only IAFA remained significantly associated with higher risk (2.7, 1.4-5.4, BMI-adjusted).
  
  
  CONCLUSIONS
  Greater visceral adiposity precedes the development of type 2 diabetes in Japanese Americans and demonstrates an effect independent of fasting insulin, insulin secretion, glycemia, total and regional adiposity, and family history of diabetes.
authors.affiliation: Epidemiologic Research and Information Center, Veterans Affairs Puget Sound, Seattle, Washington 98108, USA. eboyko@u.washington.edu
authors.forename: E J
authors.initials: EJ
authors.lastname: Boyko
authors.forename: W Y
authors.initials: WY
authors.lastname: Fujimoto
authors.forename: D L
authors.initials: DL
authors.lastname: Leonetti
authors.forename: L
authors.initials: L
authors.lastname: Newell-Morris
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology*; D000328:Adult; D044466:Asian People; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D002096:C-Peptide / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D005951:Glucose Tolerance Test; D006801:Humans; D015994:Incidence; D007328:Insulin / Q000097:blood; D007564:Japan / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D014781:Viscera; D014861:Washington / Q000453:epidemiology
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin