title: Risk Factors for Insulin Resistance, Metabolic Syndrome, and Diabetes in 248 HFE C282Y Homozygotes Identified by Population Screening in the HEIRS Study.
abstract: BACKGROUND
  We sought to identify risk factors for insulin resistance, metabolic syndrome (MetS), and diabetes mellitus in 248 non-Hispanic white HFE C282Y homozygotes identified by population screening.
  
  
  METHODS
  We analyzed observations obtained prospectively in a postscreening examination: age; sex; body mass index (BMI); systolic/diastolic blood pressure; metacarpophalangeal (MP) joint hypertrophy; hepatomegaly; complete blood counts; alanine/aspartate aminotransferase levels; elevated C-reactive protein (>0.5 mg/dL); transferrin saturation; serum ferritin; homeostasis model assessment-insulin resistance (HOMA-IR); and MetS.
  
  
  RESULTS
  Twenty-six participants (10.5%) had diabetes diagnoses. A significant trend across HOMA-IR quartiles was observed only for blood neutrophils. Logistic regression on HOMA-IR fourth quartile revealed positive associations: age (P = 0.0002); male sex (P = 0.0022); and BMI (P < 0.0001). HOMA-IR fourth quartile predicted MetS (P < 0.0001). Logistic regression on diabetes revealed positive associations: age (P = 0.0012); male sex (P = 0.0068); MP joint hypertrophy (P = 0.0167); neutrophils (P = 0.0342); and MetS (P = 0.0298). Serum ferritin did not predict HOMA-IR fourth quartile, MetS, or diabetes.
  
  
  CONCLUSIONS
  In screening C282Y homozygotes, age, male sex, and BMI predicted HOMA-IR fourth quartile. HOMA-IR fourth quartile alone predicted MetS. Diabetes was associated with greater age, male sex, MP joint hypertrophy, greater blood neutrophil counts, and MetS.
authors.affiliation: 1 Southern Iron Disorders Center , Birmingham, Alabama.|2 Department of Medicine, University of Alabama at Birmingham , Birmingham, Alabama.
authors.forename: James C
authors.initials: JC
authors.lastname: Barton
authors.affiliation: 1 Southern Iron Disorders Center , Birmingham, Alabama.
authors.forename: J Clayborn
authors.initials: JC
authors.lastname: Barton
authors.affiliation: 3 Department of Medicine, University of Western Ontario , London, Ontario, Canada .
authors.forename: Paul C
authors.initials: PC
authors.lastname: Adams
authors.affiliation: 1 Southern Iron Disorders Center , Birmingham, Alabama.|4 Department of Microbiology, University of Alabama at Birmingham , Alabama.
authors.forename: Ronald T
authors.initials: RT
authors.lastname: Acton
mesh_terms: D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D002170:Canada / Q000453:epidemiology; D016009:Chi-Square Distribution; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D056726:Genetic Association Studies; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D005820:Genetic Testing; D006432:Hemochromatosis / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D000071020:Hemochromatosis Protein / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics*; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D024821:Metabolic Syndrome / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D008875:Middle Aged; D016017:Odds Ratio; D010641:Phenotype; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D014481:United States / Q000453:epidemiology; D044465:White People / Q000235:genetics
chemical_list: D005819:Genetic Markers; C103673:HFE protein, human; D000071020:Hemochromatosis Protein