title: Use of the estimated glucose disposal rate as a measure of insulin resistance in an urban multiethnic population with type 1 diabetes.
abstract: OBJECTIVE
  Insulin resistance has been described in type 1 diabetes mellitus, is related to risk of vascular complications, and may be more common in certain ethnic groups. Estimated glucose disposal rate (eGDR) is a validated clinical tool for estimating insulin sensitivity in type 1 diabetes. Because previous reports of eGDR in adults with type 1 diabetes have included few ethnic minorities, this study explored interethnic differences in eGDR and the relationship of eGDR with diabetic vascular complications.
  
  
  METHODS
  We conducted a cross-sectional study using a sample that included 207 white, black, or Hispanic adults with prior clinical diagnosis of type 1 diabetes who were receiving care at an urban academic medical center. eGDR (milligrams per kilogram per minute) was calculated using HbA1c, waist circumference, and hypertensive status. Race/ethnicity was self-reported. Multivariable logistic regression models were used to estimate odds ratios (ORs) and 95% CIs of association of eGDR with diabetes complications (cardiovascular disease, retinopathy, albuminuria, and chronic kidney disease above stage 3).
  
  
  RESULTS
  Forty-two percent of the participants were women, and mean age was 45 ± 15 years; 34% were white, 32% were Hispanic, and 34% were black. Ethnicity was significantly associated with eGDR; blacks had significantly lower eGDR (5.66 ± 2.34) than Hispanics (6.70 ± 2.29) and whites (7.20 ± 2.03) (P < 0.001). Patients with the lowest eGDR compared with the highest had a significantly greater risk of any diabetes complication (OR 3.1 [95% CI 1.2-8.1]) compared with the least insulin-resistant patients.
  
  
  CONCLUSIONS
  In an urban clinic population of patients with type 1 diabetes, blacks were significantly less insulin sensitive than whites or Hispanics, and lower eGDR was associated with diabetes complications. Further study is needed to determine whether using eGDR to target interventions can improve outcomes.
authors.affiliation: Division of Endocrinology, Montefiore Medical Center, Bronx, New York, USA. eepstein@montefiore.org
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Epstein
authors.forename: Jamie L
authors.initials: JL
authors.lastname: Osman
authors.forename: Hillel W
authors.initials: HW
authors.lastname: Cohen
authors.forename: Swapnil N
authors.initials: SN
authors.lastname: Rajpathak
authors.forename: Oksana
authors.initials: O
authors.lastname: Lewis
authors.forename: Jill P
authors.initials: JP
authors.lastname: Crandall
mesh_terms: D000328:Adult; D044383:Black People / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D048909:Diabetes Complications / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology / Q000503:physiopathology*; D005006:Ethnicity; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006442:Glycated Hemoglobin / Q000032:analysis; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000208:ethnology; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D009519:New York City / Q000453:epidemiology; D055105:Waist Circumference / Q000208:ethnology; D044465:White People / Q000706:statistics & numerical data; D001741:Black or African American
chemical_list: D005947:Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human