title: Glutamate decarboxylase antibody levels predict rate of beta-cell decline in adult-onset diabetes.
abstract: Glutamate decarboxylase autoantibodies (GAD65Ab) and beta-cell function were evaluated at and 3 years after diabetes onset in consecutive subjects over 15 years of age. At onset, 21/32 (66%) insulin-treated patients (mean age 43, range 16-79 years) had GAD65Ab; all GAD65Ab persisted 3 years later. At onset, 20/82 (24%) non-insulin-treated patients (mean age 56, range 20-79 years) had GAD65Ab. Of those with persistent GAD65Ab, 8 non-insulin-treated and 11 insulin-treated patients consented to follow-up glucose and glucagon stimulation tests. For non-insulin-treated patients, quantitative GAD65Ab index at onset correlated inversely with 1 + 3 min C-peptide response to glucose (r = -0.68, P < 0.05) and to glucagon (r = -0.79, P < 0.05) 3 years later. Those with high (> 0.50) initial GAD65Ab index had lower C-peptide (fasting, 1 + 3 min after glucose and after glucagon) 3 years later, versus those with low (< 0.50) initial GAD65Ab index (P < 0.05). In conclusion, not only did GAD65Ab presence predict future insulin dependence, but higher GAD65Ab levels may mark more rapid decline in beta-cell function in apparent non-insulin-dependent diabetes.
authors.affiliation: Department of Medicine, University of Lund, Malmö General Hospital, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Gottsäter
authors.forename: M
authors.initials: M
authors.lastname: Landin-Olsson
authors.forename: A
authors.initials: A
authors.lastname: Lernmark
authors.forename: P
authors.initials: P
authors.lastname: Fernlund
authors.forename: G
authors.initials: G
authors.lastname: Sundkvist
authors.forename: W A
authors.initials: WA
authors.lastname: Hagopian
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000276:immunology / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000276:immunology / Q000503:physiopathology*; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007515:Islets of Langerhans / Q000473:pathology / Q000503:physiopathology*; D008875:Middle Aged; D011237:Predictive Value of Tests; D011994:Recombinant Proteins / Q000276:immunology; D018709:Statistics, Nonparametric
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D005968:Glutamate Decarboxylase; D006442:Glycated Hemoglobin; D011994:Recombinant Proteins