Reducing Rates of Severe Hypoglycemia in a Population-Based Cohort of Children and Adolescents With Type 1 Diabetes Over the Decade 2000–2009

OBJECTIVE: To examine rates of severe hypoglycemia (SH) in a large population-based cohort of children with type 1 diabetes and relationships to HbA(1c). RESEARCH DESIGN AND METHODS: Data from 1,683 children (mean [SD] age at diagnosis 10.5 [4.2]; range 1-18 years) from 2000 to 2009 were analyzed from the Western Australian Children's Diabetes Database. Rates of SH were related to HbA(1c) using negative binomial regression. RESULTS: A total of 7,378 patient-years of data and 780 SH events were recorded. The rate of SH per 100 patient-years peaked at 17.3 in 2001 and then declined from 2004 to a nadir of 5.8 in 2006. HbA(1c) <7% was not associated with higher risk of SH (incidence rate ratio 1.2 [95% CI 0.9-1.6], P = 0.29) compared with HbA(1c) of 8-9%. CONCLUSIONS: In a sample of youth with type 1 diabetes, there has been a decrease in rates of SH and a weaker relationship with glycemic control than previously observed.