PREVALENCE OF DIABETES-SPECIFIC AUTOANTIBODIES IN PATIENTS AT RISK FOR ADULT-ONSET DIABETES-MELLITUS

To evaluate the potential of autoimmune markers in identifying patient s with slowly progressive IDDM in the prediabetic state, we screened a population of 151 patients aged 37-70 years with impaired glucose tol erance (IGT) for the presence of islet cell antibodies (ICA), insulin autoantibodies (IAA), antibodies to glutamic acid decarboxylase (GADA) , and antibodies to tyrosine phosphatase IA-2 (IA-2A). Autoantibodies were found in 5 (3.3%) patients with IGT suggesting the presence of an autoimmune-mediated Beta cell destruction. All of them were positive for high level ICA (>20 JDF-U) and 1 ICA positive subject had addition al GADA (100 GADA-U). In contrast, none of the subjects had IA-2A or I AA. We here demonstrate a low prevalence of autoimmune diabetes among middle-aged subjects with IGT. ICA and GADA but not IA-2A or IAA may r epresent autoimmune markers for slowly progressive IDDM before the man ifestation of the disease.