title: Gestational diabetes identifies women at risk for permanent type 1 and type 2 diabetes in fertile age: predictive role of autoantibodies.
abstract: OBJECTIVE
  Our aim was to evaluate the predictive value of gestational diabetes mellitus (GDM), diabetes-associated autoantibodies, and other factors for development of clinical diabetes later in life.
  
  
  METHODS
  In this case-control study the presence of autoantibodies was studied in 435 women with GDM and in healthy matched control subjects. The need for exogenous insulin during GDM was recorded. In the GDM group, the mean follow-up period was 5.7 years and in the control group 6.1 years.
  
  
  RESULTS
  Among the subjects with GDM, 20 (4.6%) developed type 1 diabetes and 23 (5.3%) developed type 2 diabetes, whereas none of the control subjects became diabetic. Two-thirds of those who developed type 1 diabetes tested positive initially for islet cell antibodies (ICAs), whereas 56% of them had autoantibodies to GAD (GADAs) and 38% to the protein tyrosine phosphatase-related IA-2 molecule. Only 2 of the 23 women who presented later with type 2 diabetes tested positive for autoantibodies. According to multivariate analysis, initial age < or =30 years, the need for insulin treatment for GDM, and antibody positivity for ICAs and GADAs were associated with increased risk for clinical type 1 diabetes.
  
  
  CONCLUSIONS
  Pregnancy seems to identify women who are at risk of developing diabetes later in life. About 10% of Finnish women with GDM will develop diabetes over the next 6 years; nearly half of them develop type 1 diabetes and the other half type 2 diabetes. Age < or =30 years, the need for insulin treatment during pregnancy, and positivity for ICAs and GADAs confer a high risk of subsequent progression to type 1 diabetes in women affected by GDM.
authors.affiliation: Department of Obstetrics & Gynecology, Oulu University Hospital, P.O. Box 5000, Oulu 90014, Finland. juha.tapanainen@oulu.fi
authors.forename: Ilkka Y
authors.initials: IY
authors.lastname: Järvelä
authors.forename: Jaana
authors.initials: J
authors.lastname: Juutinen
authors.forename: Pentti
authors.initials: P
authors.lastname: Koskela
authors.forename: Anna-Liisa
authors.initials: AL
authors.lastname: Hartikainen
authors.forename: Petri
authors.initials: P
authors.lastname: Kulmala
authors.forename: Mikael
authors.initials: M
authors.lastname: Knip
authors.forename: Juha S
authors.initials: JS
authors.lastname: Tapanainen
mesh_terms: D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000032:analysis*; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000209:etiology*; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology*; D016640:Diabetes, Gestational / Q000175:diagnosis*; D005260:Female; D005968:Glutamate Decarboxylase / Q000276:immunology; D006801:Humans; D007330:Insulin Antibodies / Q000276:immunology; D007515:Islets of Langerhans / Q000276:immunology; D011237:Predictive Value of Tests; D011247:Pregnancy; D012306:Risk
chemical_list: D001323:Autoantibodies; C096322:ICA512 autoantibody; D007330:Insulin Antibodies; D005968:Glutamate Decarboxylase