Study. Diabetes Care

Why Holstein et al. (1) report intheir current study considerablylower incidences of severe hypo-glycemic events in patients with type 1 and type 2 diabetes is not clear. The au-thors purport that their study is popula-tion based. There is, however, substantial doubt that ascertainment of diabetic patients with severe hypoglycemia was really complete in the region under inves-tigation with 200,000 inhabitants in North-Rhine Westphalia, Germany. In the article, incidence of severe hypoglyce-mia in patients with type 1 diabetes was 11.5 in the first period and 23.4 episodes/ 100,000 person-years in the second pe-riod. In patients with type 2 diabetes 18.5 and 32.6 episodes/100,000 person-years were observed in both periods. As-suming for type 1 diabetes a population prevalence in Germany of 0.3%, which is a rather conservative estimate, and for type 2 diabetes a prevalence of 9 % in this region of Germany (2), incidence of se-vere hypoglycemic episodes is calculated for type 1 diabetes to be 3.8 in the first period and 7.8 episodes/100 patient-years in the later period and for type 2 diabetes 0.2 and 0.4 episodes/100 patient-years in both periods. These fig-ures are considerably lower than those reported in population-based studies. I