Ketoacidosis in young adults is not related to the islet antibodies at thediagnosis of Type 1 diabetes mellitus - a nationwide study

Aims To test the hypothesis that there is lower prevalence of islet antibod ies in subjects with newly diagnosed Type 1 diabetes mellitus in young adul thood than in children is associated with less severe diabetes at time of d iagnosis, Methods This investigation was based on a nationwide study (Diabetes Incide nce Study in Sweden) of 15-34-year-old newly diagnosed diabetic subjects. D uring 1992-1993, all diabetic subjects (excluding secondary and gestational diabetes) were reported on standardized forms, with information about clin ical characteristics at diagnosis. The study examined islet cell antibodies (ICA) by indirect immunofluorescence, and autoantibodies to glutamic acid decarboxylase (GADA), tyrosine phosphatase-like antigen (IA-2A) and insulin (IAA) as well as C-peptide by radioimmunoassay. Results Blood samples were available from 78 patients with diabetic ketoaci dosis (DKA) and 517 non-acidotic patients. The prevalence of ICA (63% vs, 5 7%), GADA (63% vs. 66%), IA-2A (35% vs, 44%) and IAA (20% vs, 15%) were ver y similar in patients with or without DKA. The median levels of the four au toantibodies did not differ between the two groups, High blood glucose (P < 0.001) and low C-peptide levels (P < 0.001) were the only parameters found to be related to DKA. Conclusions The similarities in findings of newly diagnosed diabetic patien ts with or without DKA regarding ICA, GADA, IA-2A and IAA suggest that ther e is no relationship between the expression of antigenicity and the severit y of beta-cell dysfunction, The lower prevalence of the four autoantibodies in 15-34-year-old diabetic subjects compared with previous findings in chi ldren is not explained by misclassification of diabetes type.