TY - BOOK AU - Park, Jean Y TI - Islet Autoimmunity is Highly Prevalent and Associated With Diminished beta-Cell Function in Patients With Type 2 Diabetes in the Grade Study PY - 2022/// KW - IN PROCESS -- NOT YET INDEXED KW - MedStar Medical Group KW - Journal Article N1 - Available online from MWHC library: 1995 - present (after 3 months), Available in print through MWHC library: 1999 - 2006 N2 - Islet autoimmunity may contribute to beta-cell dysfunction in type 2 diabetes (T2D). Its prevalence and clinical significance have not been rigorously determined. In this ancillary study to the Glycemia Reduction Approaches in Diabetes-A Comparative Effectiveness (GRADE) Study, we investigated the prevalence of cellular and humoral islet autoimmunity in patients with T2D duration 4.0+/-3.0 y, HbA1c 7.5+/-0.5% on metformin alone. We measured T cell autoreactivity against islet proteins, islet autoantibodies against GAD65, IA2, ZnT8, and beta-cell function. Cellular islet autoimmunity was present in 41.3%, humoral islet autoimmunity in 13.5%, and both in 5.3%. beta-cell function calculated as iAUC-CG and DELTAC-peptide(0- 30)/DELTAglucose(0-30) from an oral glucose tolerance test was lower among T cell-positives (T+) than T cell-negatives (T-) using two different adjustments for insulin sensitivity (iAUC-CG: 13.2% [95% CI 0.3, 24.4%] or 11.4% [95% CI 0.4, 21.2%] lower; DELTAC-peptide(0-30)/DELTAglucose(0-30)) 19% [95% CI 3.1, 32.3%] or 17.7% [95% CI 2.6, 30.5%] lower). T+ patients had 17% higher HbA1c (95% CI 0.07, 0.28) and 7.7 mg/dL higher fasting plasma glucose levels (95% CI 0.2,15.3) than T- patients. We conclude that islet autoimmunity is much more prevalent in T2D patients than previously reported. T cell-mediated autoimmunity is associated with diminished beta-cell function and worse glycemic control. Copyright (c) 2022 by the American Diabetes Association UR - https://dx.doi.org/10.2337/db21-0590 ER -