title: Newly diagnosed latent autoimmune diabetes in adults (LADA) is associated with low level glutamate decarboxylase (GAD65) and IA-2 autoantibodies. Diabetes Incidence Study in Sweden (DISS).
abstract: A quantitative assay with microSepharose was used to determine GAD65Ab and IA-2Ab levels in 771 population-based patients diagnosed with diabetes mellitus at 15 to 34 years of age, and in 828 matched controls. Among the patients, 587 (76%) were classified with type I, 108 (14%) with type II, and 76 (10%) with unclassifiable diabetes. The levels above normal demonstrated a prevalence of GAD65Ab in 66% of type I diabetes, 50% of type II diabetes and 54% of unclassifiable patients and for IA-2Ab in 40%, 17% and 21%, respectively. Among the autoantibody-positive sera, the LADA patients had a lower GAD65Ab index (median 0.19, p < 0.0001) and IA-2Ab index (median 0.28, p < 0.0001) than the type I patients (median 0.37 and 0.66). Patients with unclassifiable diabetes had a GAD65Ab (median 0.43) or IA-2Ab (median 0.63) index which was not different from the type I diabetes patients. Our data demonstrate that young adult new-onset LADA patients have low level GAD65Ab and IA-2Ab. The low-level autoantibodies may signify a less aggressive beta-cell autoimmunity, which may explain why these patients are often classified with type II or non-insulin-dependent diabetes.
authors.affiliation: Department of Medicine, University of Washington, Seattle 98195, USA.
authors.forename: D B
authors.initials: DB
authors.lastname: Schranz
authors.forename: L
authors.initials: L
authors.lastname: Bekris
authors.forename: M
authors.initials: M
authors.lastname: Landin-Olsson
authors.forename: C
authors.initials: C
authors.lastname: Törn
authors.forename: A
authors.initials: A
authors.lastname: Niläng
authors.forename: A
authors.initials: A
authors.lastname: Toll
authors.forename: J
authors.initials: J
authors.lastname: Sjöström
authors.forename: H
authors.initials: H
authors.lastname: Grönlund
authors.forename: A
authors.initials: A
authors.lastname: Lernmark
mesh_terms: D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000097:blood* / Q000302:isolation & purification; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000201:enzymology / Q000276:immunology*; D015415:Biomarkers; D003922:Diabetes Mellitus, Type 1 / Q000201:enzymology / Q000276:immunology*; D003924:Diabetes Mellitus, Type 2 / Q000201:enzymology / Q000276:immunology*; D005260:Female; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006801:Humans; D007515:Islets of Langerhans / Q000276:immunology; D008297:Male; D012685:Sepharose
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D012685:Sepharose; D005968:Glutamate Decarboxylase