Comment on: Cryer. Severe Hypoglycemia Predicts Mortality in Diabetes. Diabetes Care 2012;35:1814–1816

In a commentary by Cryer (1), we came across his statement that “it is sobering to think that as many as 1 in 25—or even 1 in 10—patients with type 1 diabetes will die of iatrogenic hypoglycemia.” We have seen several thousands of patients with type 1 diabetes, but we can remember only very few patients who have died of hypoglycemia. We looked at the references cited in the article as proof for this high number of hypoglycemic deaths. In these articles, the incidences of death due to hypoglycemia were 1 (2), 15 (3), 15 (4), and 21/100,000 patient-years (5). Assuming a mean incidence of 13/100,000 patient-years and a mean diabetes duration until death of 50 years, the lifetime incidence of death due to hypoglycemia is 0.65/100 patients. The high relative proportion of deaths related to hypoglycemia in these studies, as calculated by Cryer (1), is certainly mainly due to the young age at diabetes onset and the relatively short follow-up periods. The longest follow-up period was 24.2 years in the article by Skrivarhaug et al. (5), in which children who were diagnosed at <15 years of age have been investigated. At later ages, long-term diabetes complications are much more frequently related to mortality, which will even give rise to a lower relative fraction of deaths related to hypoglycemia. We admit that 0.65 deaths due to hypoglycemia/100 patients is still too high and everything must be done in our young patients to further reduce it, but it is at least by the factor 10 lower than stated in the article by Cryer (1).