title: Do men develop type 2 diabetes at lower body mass indices than women?
abstract: OBJECTIVE
  To describe the associations between age, sex and BMI at diagnosis of type 2 diabetes, and test the hypothesis that men are diagnosed with diabetes at lower average BMI than women of similar age.
  
  
  METHODS
  Linear regression was used to estimate and compare the relationship between age and BMI at diagnosis among 51,920 men and 43,137 women included in a population-based diabetes register in Scotland for whom an index BMI measurement was taken within 1 year of diabetes diagnosis. We also examined HbA(1c) values by sex within the same timescale.
  
  
  RESULTS
  Mean BMI closest to date of diagnosis of type 2 diabetes mellitus was 31.83 kg/m(2) (SD 5.13) in men and 33.69 kg/m(2) (SD 6.43) in women. The inverse relationship between age and BMI at diagnosis of type 2 diabetes mellitus was significantly steeper in women than in men (slope estimate in men -0.12 kg/m(2) per year [95% CI -0.13, -0.12] women -0.18 kg/m(2) per year [95% CI -0.18, -0.17], p < 0.0001 for formal test of interaction). Mean BMI difference was most marked at younger ages and narrowed with advancing age. However, HbA(1c) levels within 1 year of diagnoses were broadly similar in men and women.
  
  
  CONCLUSIONS
  Men are diagnosed with type 2 diabetes at lower BMI than women across the age range. This observation may help explain why type 2 diabetes is more common among middle-aged men in populations of European extraction. Whether the same pattern is also observed in other ethnic groups requires confirmation.
authors.affiliation: BHF Glasgow Cardiovascular Research Centre, Faculty of Medicine, University of Glasgow, Glasgow, G12 8TA, Scotland, UK.
authors.forename: J
authors.initials: J
authors.lastname: Logue
authors.forename: J J
authors.initials: JJ
authors.lastname: Walker
authors.forename: H M
authors.initials: HM
authors.lastname: Colhoun
authors.forename: G P
authors.initials: GP
authors.lastname: Leese
authors.forename: R S
authors.initials: RS
authors.lastname: Lindsay
authors.forename: J A
authors.initials: JA
authors.lastname: McKnight
authors.forename: A D
authors.initials: AD
authors.lastname: Morris
authors.forename: D W
authors.initials: DW
authors.lastname: Pearson
authors.forename: J R
authors.initials: JR
authors.lastname: Petrie
authors.forename: S
authors.initials: S
authors.lastname: Philip
authors.forename: S H
authors.initials: SH
authors.lastname: Wild
authors.forename: N
authors.initials: N
authors.lastname: Sattar
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D012306:Risk; D012606:Scotland / Q000453:epidemiology; D012737:Sex Factors
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human