title: Characteristics of childhood and adult-onset type 1 diabetes in a multi-ethnic population.
abstract: OBJECTIVE
  To compare patients with classic type 1 diabetes (T1D) diagnosed in childhood and adulthood regarding clinical presentation, GADA and HLA DR B1*03/04 prevalence in a multi-ethnic population.
  
  
  METHODS
  We studied 83 Brazilian patients with classic T1D divided in 2 groups: (1) diagnosed before 20 years old (n=42); (2) diagnosed at age 20 and up (n=41). All were interviewed and blood was sampled for GADA measurement and HLA DR B1 typing.
  
  
  RESULTS
  The study population comprised 52 women and 31 men, 52 white and 31 non-white individuals with mean age of 29.94 (+/-10.95) years and mean disease duration of 10.37 (+/-7.37) years. The mean age at onset in groups 1 and 2 were, respectively, 11.48 and 27.2 years old. There were no significant differences between groups regarding diabetic ketoacidosis at presentation. A longer symptomatic period preceding the diagnosis was observed in group 2 (p=0.039). The prevalence of GADA and HLA DR B1*03/04 was similar between groups. HLA DR B1*13 was significantly more common in the group 1 (p=0.024). GADA was more prevalent among patients with HLA DR B1*03 (p=0.02).
  
  
  CONCLUSIONS
  In this study, T1D diagnosed in adulthood was associated with longer symptomatic period preceding diagnosis and lower prevalence of HLA DR B1*13, but there were no differences regarding ketoacidosis as a form of disease presentation, GADA (+) or HLA DR B1* 03/04.
authors.affiliation: Diabetes and Immunology Sections, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. melanie.rodacki@joslin.harvard.edu
authors.forename: Melanie
authors.initials: M
authors.lastname: Rodacki
authors.forename: Lenita
authors.initials: L
authors.lastname: Zajdenverg
authors.forename: Rosangela Prendin
authors.initials: RP
authors.lastname: Tortora
authors.forename: Fabiola Aarao
authors.initials: FA
authors.lastname: Reis
authors.forename: Martha S
authors.initials: MS
authors.lastname: Albernaz
authors.forename: Maria Rocio Bencke
authors.initials: MR
authors.lastname: Goncalves
authors.forename: Adolpho
authors.initials: A
authors.lastname: Milech
authors.forename: Jose Egidio Paulo
authors.initials: JE
authors.lastname: de Oliveira
mesh_terms: D000328:Adult; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics / Q000276:immunology / Q000503:physiopathology*; D005006:Ethnicity; D005190:Family; D005260:Female; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D006801:Humans; D007330:Insulin Antibodies / Q000097:blood; D008297:Male
chemical_list: D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; D007330:Insulin Antibodies