title: Glycated Hemoglobin, Fasting Insulin and the Metabolic Syndrome in Males. Cross-Sectional Analyses of the Aragon Workers' Health Study Baseline.
abstract: OBJECTIVE
  Glycated hemoglobin (HbA1c) is currently used to diagnose diabetes mellitus, while insulin has been relegated to research. Both, however, may help understanding the metabolic syndrome and profiling patients. We examined the association of HbA1c and fasting insulin with clustering of metabolic syndrome criteria and insulin resistance as two essential characteristics of the metabolic syndrome.
  
  
  METHODS
  We used baseline data from 3200 non-diabetic male participants in the Aragon Workers' Health Study. We conducted analysis to estimate age-adjusted odds ratios (ORs) across tertiles of HbA1c and insulin. Fasting glucose and Homeostatic model assessment - Insulin Resistance were used as reference. Here we report the uppermost-to-lowest tertile ORs (95%CI).
  
  
  RESULTS
  Mean age (SD) was 48.5 (8.8) years and 23% of participants had metabolic syndrome. The ORs for metabolic syndrome criteria tended to be higher across HbA1c than across glucose, except for high blood pressure. Insulin was associated with the criteria more strongly than HbA1c and similarly to Homeostatic model assessment - Insulin Resistance (HOMA-IR). For metabolic syndrome, the OR of HbA1c was 2.68, of insulin, 11.36, of glucose, 7.03, and of HOMA-IR, 14.40. For the clustering of 2 or more non-glycemic criteria, the OR of HbA1c was 2.10, of insulin, 8.94, of glucose, 1.73, and of HOMA-IR, 7.83. All ORs were statistically significant. The areas under the receiver operating characteristics curves for metabolic syndrome were 0.670 (across HbA1c values) and 0.770 (across insulin values), and, for insulin resistance, 0.647 (HbA1c) and 0.995 (insulin). Among non-metabolic syndrome patients, a small insulin elevation identified risk factor clustering.
  
  
  CONCLUSIONS
  HbA1c and specially insulin levels were associated with metabolic syndrome criteria, their clustering, and insulin resistance. Insulin could provide early information in subjects prone to develop metabolic syndrome.
authors.affiliation: Department of Epidemiogy, Atherothrombosis and Imaging, Spanish National Center for Cardiovascular Research (CNIC), Madrid, Spain.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Saravia
authors.affiliation: Instituto Aragonés de Ciencias de la Salud (I+CS), Zaragoza, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Civeira
authors.affiliation: Department of Epidemiogy, Atherothrombosis and Imaging, Spanish National Center for Cardiovascular Research (CNIC), Madrid, Spain; Boca Raton Clinical Research Global Peru, Lima, Peru.
authors.forename: Yamilee
authors.initials: Y
authors.lastname: Hurtado-Roca
authors.affiliation: Instituto de Investigación 12 de Octubre. CIBER-Epidemiología y Salud Pública, Madrid, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Andres
authors.affiliation: Instituto Aragonés de Ciencias de la Salud (I+CS), Zaragoza, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Leon
authors.affiliation: Instituto Aragonés de Ciencias de la Salud (I+CS), Zaragoza, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Pocovi
authors.affiliation: Department of Epidemiogy, Atherothrombosis and Imaging, Spanish National Center for Cardiovascular Research (CNIC), Madrid, Spain.
authors.forename: Jose
authors.initials: J
authors.lastname: Ordovas
authors.affiliation: Departments of Epidemiology and Medicine, and Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America.
authors.forename: Eliseo
authors.initials: E
authors.lastname: Guallar
authors.affiliation: Department of Epidemiogy, Atherothrombosis and Imaging, Spanish National Center for Cardiovascular Research (CNIC), Madrid, Spain; Hospital Clínico San Carlos, Universidad Complutense, Madrid, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Fernandez-Ortiz
authors.affiliation: Instituto Aragonés de Ciencias de la Salud (I+CS), Zaragoza, Spain.
authors.forename: Jose Antonio
authors.initials: JA
authors.lastname: Casasnovas
authors.affiliation: Department of Epidemiogy, Atherothrombosis and Imaging, Spanish National Center for Cardiovascular Research (CNIC), Madrid, Spain; Department of Preventive Medicine and Public Health, School of Medicine, Universidad Autonoma de Madrid, Madrid, Spain; Department of Epidemiology, St. Louis University, St Louis, Missouri, United States of America.
authors.forename: Martin
authors.initials: M
authors.lastname: Laclaustra
mesh_terms: D000328:Adult; D000959:Antihypertensive Agents / Q000627:therapeutic use; D015331:Cohort Studies; D015897:Comorbidity; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology; D005215:Fasting / Q000097:blood; D006442:Glycated Hemoglobin / Q000032:analysis*; D006706:Homeostasis; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000453:epidemiology; D008875:Middle Aged; D008954:Models, Biological; D016272:Occupational Health; D016017:Odds Ratio; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D014280:Triglycerides / Q000097:blood; D055105:Waist Circumference
chemical_list: D000959:Antihypertensive Agents; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; D014280:Triglycerides