Prevalence of Type 1 Diabetes Correlates with Daily Insulin Dose, Adverse Outcomes and with Autoimmune Process Against Glutamic Acid Decarboxylase in Adults

The territorial differences in the prevalence of type 1 diabetes mellitus (T1D) around the world were previously reported (Amos et al., 1997; Green & Patterson, 2001; Lévy-Marchal, 2001), but the data were based on the study of juvenile T1D epidemiology, i.e., in patients diagnosed with T1D before the age of 15 years. These data became the basis for the epidemiological evaluation of the whole T1D patient population. With the relatively limited number of children with T1D within the current territory, less effort is required for data gathering. Besides, as the age increases, it becomes more difficult to relate a diabetic condition to a certain diabetes type (Keen, 1998), thus, making it impossible to directly use the diabetes-type data obtained from Primary Care. In modern epidemiological studies, the key data concern the age at the time of the diagnosis—patients who were diagnosed before the age of 30 years and are insulin-treated, are considered to suffer from T1D.