title: Specific relation between abdominal obesity and early-phase hyperglycemia is modulated by hepatic insulin resistance in healthy older women.
abstract: OBJECTIVE
  To describe the impact of abdominal obesity and hepatic insulin resistance on phase-specific glycemic responses in older women.
  
  
  METHODS
  We studied 23 healthy older women (60-88 years old). Abdominal obesity was defined by an abdominal circumference > or =95 cm. Plasma glucose and insulin were measured in response to a 3-h oral glucose tolerance test. Insulin suppression of hepatic glucose production was determined using in vivo clamp techniques.
  
  
  RESULTS
  Despite identical prevailing insulin concentrations, glucose excursions 30 min postchallenge (but not later) were greater in women with abdominal obesity than in those without (162 +/- 19 vs. 132 +/- 16 mg/dl; P < 0.01). There was a strong correlation between hepatic glucose production suppression under low-dose insulin infusion and early-phase glucose excursions from the oral glucose tolerance test (r = -0.83; P < 0.001) in women with abdominal obesity, but not in women without (r = 0.44; P < 0.11).
  
  
  CONCLUSIONS
  Abdominal obesity relates specifically to early-phase hyperglycemia via hepatic insulin resistance, even in healthy older women.
authors.affiliation: John B. Pierce Laboratory, Yale University School of Medicine, New Haven, Connecticut, USA. esclxd@gwumc.edu
authors.forename: Loretta
authors.initials: L
authors.lastname: DiPietro
authors.forename: James
authors.initials: J
authors.lastname: Dziura
authors.forename: Catherine W
authors.initials: CW
authors.lastname: Yeckel
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D006943:Hyperglycemia / Q000097:blood / Q000175:diagnosis* / Q000209:etiology*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D008875:Middle Aged; D056128:Obesity, Abdominal / Q000097:blood / Q000150:complications*; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D007328:Insulin