Zinc transporter 8 autoantibodies complement glutamic acid decarboxylase and insulinoma‐associated antigen‐2 autoantibodies in the identification and characterization of Japanese type 1 diabetes

Abstract Aims/Introduction This study aimed to investigate the significance of zinc transporter 8 autoantibody (ZnT8A) in identifying and characterizing autoimmune‐mediated type 1 diabetes in Japanese individuals. Methods ZnT8A were determined in 324 patients with type 1 diabetes, 191 phenotypic type 2 diabetes and 288 healthy control individuals using bridging‐type enzyme‐linked immunosorbent assay in addition to autoantibodies to glutamic acid decarboxylase and insulinoma‐associated antigen‐2. Results We set a cut‐off value of 10.0 U/mL, and 25% of the type 1 diabetic patients had ZnT8A levels exceeding this level. The prevalence of ZnT8A was significantly higher in patients with acute‐onset type 1 diabetes than in those with slowly progressive and fulminant type 1 diabetes (P