Time to insulin initiation cannot be used in defining latent autoimmune diabetes in adults

OBJECTIVE - Latent autoimmune diabetes in adults is type I diabetes presenting as noninsulin dependent diabetes. One feature of the selection criteria is Lime independent of insulin treatment. We examine the validity of this criterion. RESEARCH DESIGN AND METHODS - Patients were recruited in nine European centers, and clinicians reported on criteria for initiating insulin. All patients were tested for GAD antibodies (GADAs) in a central laboratory. We examined time to insulin treatment for GADA-positive patients in six participating centers. RESULTS - There was intercenter variation in the criteria used to initiate insulin. Median time to insulin was 16.15 months (interqartile range 6.7-25.5) in centers with GADA testing compared with 45.6 months (29.5-61.8) in centers without routine GADA testing (P < 0.002). CONCLUSION - Time to insulin should not be used to define patients with LADA because it is dependent on local clinical judgment and the use of laboratory tests for GADA.