title: Quantitative insulin sensitivity check index and the reciprocal index of homeostasis model assessment in normal range weight and moderately obese type 2 diabetic patients.
abstract: OBJECTIVE
  To investigate whether the quantitative insulin sensitivity check index (QUICKI) and the reciprocal index of homeostasis model assessment (1/HOMA-IR) derived from fasting plasma glucose and insulin level are excellent surrogate indices of insulin resistance in both normal range-weight and moderately obese type 2 diabetic and healthy subjects.
  
  
  METHODS
  The association between QUICKI or 1/HOMA-IR and insulin resistance index assessed by euglycemic-hyperinsulinemic clamp (clamp-IR) was investigated in 121 type 2 diabetic and 29 healthy subjects recruited from among 120 (age 55 +/- 11, 48 +/- 15, and 52 +/- 15 years [means +/- SD], respectively). Type 2 diabetic subjects were divided into groups of 76 normal range-weight and 45 moderately obese subjects (BMI 21.4 +/- 2.3 vs. 27.2 +/- 2.2 kg/m(2), P < 0.0001).
  
  
  RESULTS
  QUICKI and 1/HOMA-IR were significantly lower in the moderately obese group than in the normal range-weight type 2 diabetic and healthy groups (n = 120) (QUICKI, 0.338 +/- 0.030, 0.371 +/- 0.037, and 0.389 +/- 0.041, respectively, P < 0.0001; 1/HOMA-IR, 0.50 +/- 0.33, 0.92 +/- 0.55, and 1.24 +/- 0.82, P < 0.0001). QUICKI was strongly correlated with clamp-IR in normal range-weight, moderately obese type 2 diabetic, and healthy subjects (r = 0.641, 0.570, and 0.502, respectively; all subjects, r = 0.608, P < 0.01) and 1/HOMA-IR exhibited correlations comparable to those of QUICKI with clamp-IR (r = 0.637, 0.530, and 0.461, respectively; all subjects, r = 0.589, P < 0.001). In multiple regression models including QUICKI or 1/HOMA-IR as an independent variable, the estimation formula accounted for 55% of the variability of clamp-IR for the group of all type 2 diabetic subjects (R(2) = 0.547 and 0.551, respectively, P <or= 0.0001).
  
  
  CONCLUSIONS
  QUICKI and 1/HOMA-IR were highly correlated with clamp-IR, with comparable coefficients in both normal range-weight and moderately obese type 2 diabetic patients and nondiabetic subjects. The latter can probably be applied clinically in view of its convenience.
authors.affiliation: Osaka City University Graduate School of Medicine, Metabolism, Endocrinology and Molecular Medicine, Osaka, Japan.
authors.forename: Hisayo
authors.initials: H
authors.lastname: Yokoyama
authors.forename: Masanori
authors.initials: M
authors.lastname: Emoto
authors.forename: Shigehiko
authors.initials: S
authors.lastname: Fujiwara
authors.forename: Koka
authors.initials: K
authors.lastname: Motoyama
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Morioka
authors.forename: Miyoko
authors.initials: M
authors.lastname: Komatsu
authors.forename: Hideki
authors.initials: H
authors.lastname: Tahara
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Shoji
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Okuno
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Nishizawa
mesh_terms: D000328:Adult; D000368:Aged; D001835:Body Weight; D003920:Diabetes Mellitus / Q000175:diagnosis* / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis* / Q000503:physiopathology*; D005260:Female; D015309:Glucose Clamp Technique; D006706:Homeostasis; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009765:Obesity; D011237:Predictive Value of Tests; D012044:Regression Analysis