title: Total and high molecular weight adiponectin have similar utility for the identification of insulin resistance.
abstract: BACKGROUND
  Insulin resistance (IR) and related metabolic disturbances are characterized by low levels of adiponectin. High molecular weight adiponectin (HMWA) is considered the active form of adiponectin and a better marker of IR than total adiponectin. The objective of this study is to compare the utility of total adiponectin, HMWA and the HMWA/total adiponectin index (SA index) for the identification of IR and related metabolic conditions.
  
  
  METHODS
  A cross-sectional analysis was performed in a group of ambulatory subjects, aged 20 to 70 years, in Mexico City. Areas under the receiver operator characteristic (ROC) curve for total, HMWA and the SA index were plotted for the identification of metabolic disturbances. Sensitivity and specificity, positive and negative predictive values, and accuracy for the identification of IR were calculated.
  
  
  RESULTS
  The study included 101 men and 168 women. The areas under the ROC curve for total and HMWA for the identification of IR (0.664 vs. 0.669, P = 0.74), obesity (0.592 vs. 0.610, P = 0.32), hypertriglyceridemia (0.661 vs. 0.671, P = 0.50) and hypoalphalipoproteinemia (0.624 vs. 0.633, P = 0.58) were similar. A total adiponectin level of 8.03 mug/ml was associated with a sensitivity of 57.6%, a specificity of 65.9%, a positive predictive value of 50.0%, a negative predictive value of 72.4%, and an accuracy of 62.7% for the diagnosis of IR. The corresponding figures for a HMWA value of 4.25 mug/dl were 59.6%, 67.1%, 51.8%, 73.7% and 64.2%.The area under the ROC curve of the SA index for the identification of IR was 0.622 [95% CI 0.554-0.691], obesity 0.613 [95% CI 0.536-0.689], hypertriglyceridemia 0.616 [95% CI 0.549-0.683], and hypoalphalipoproteinemia 0.606 [95% CI 0.535-0.677].
  
  
  CONCLUSIONS
  Total adiponectin, HMWA and the SA index had similar utility for the identification of IR and metabolic disturbances.
authors.affiliation: Departamento de Endocrinología y Metabolismo Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán 14000 México DF, México.
authors.forename: Paloma
authors.initials: P
authors.lastname: Almeda-Valdes
authors.forename: Daniel
authors.initials: D
authors.lastname: Cuevas-Ramos
authors.forename: Roopa
authors.initials: R
authors.lastname: Mehta
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Gomez-Perez
authors.forename: Ivette
authors.initials: I
authors.lastname: Cruz-Bautista
authors.forename: Olimpia
authors.initials: O
authors.lastname: Arellano-Campos
authors.forename: Mariana
authors.initials: M
authors.lastname: Navarrete-Lopez
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Aguilar-Salinas
mesh_terms: D052242:Adiponectin / Q000097:blood; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015228:Hypertriglyceridemia / Q000097:blood* / Q000503:physiopathology; D052456:Hypoalphalipoproteinemias / Q000097:blood* / Q000503:physiopathology; D007333:Insulin Resistance; D008297:Male; D008800:Mexico; D008875:Middle Aged; D008970:Molecular Weight; D009765:Obesity / Q000097:blood* / Q000503:physiopathology; D011237:Predictive Value of Tests; D012372:ROC Curve; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: C499918:ADIPOQ protein, human; D052242:Adiponectin; D015415:Biomarkers