Approximately 40 years ago it became increasingly clear that there existed a group of individuals diagnosed with diabetes who did not require insulin at the outset, but possessed pancreatic islet cell autoantibodies. Over time this cohort progressed to insulin dependence.
Because insulin was not initially necessary and presentation was not with diabetic ketoacidosis (DKA) this group of people were usually diagnosed with type 2 diabetes (T2DM). However, the finding of islet cell autoantibodies and the ultimate requirement for insulin were features more consistent with type 1 diabetes (T1DM). The term latent autoimmune disease in adults (LADA) was introduced to describe the profile of these individuals with this slowly progressing form of autoimmune diabetes, displaying a phenotype intermediate between T1DM and T2DM.1 LADA has been described as type 1.5 DM.