Type 1 diabetes incidence and prevalence trends in a cohort of Canadian children and youth.

BACKGROUND AND OBJECTIVE: Incidence rates of type 1 diabetes have long been on the rise across the globe, however, there is emerging evidence that the rate of rise may be slowing. The objective of this study was to describe trends in the incidence and prevalence of type 1 diabetes in a sample of Canadian children and youth.

METHODS: Cases were extracted using linked administrative datasets and a validated diabetes case-finding definition. Incidence and prevalence trends were analyzed using the JoinPoint regression analysis program.

RESULTS: A small increase in the incidence of type 1 diabetes was observed over the 11-year period from 2002-2003 to 2012-2013. Total incident cases per year ranged from 201 (2005-2006) to 250 (2007-2008). Total prevalent cases per year ranged from 1790 (2002-2003) to 2264 (2012-2013). Incidence was highest among children aged 5 to 14 years, and lowest in the youngest (1-4 years) and oldest (15-19 years) age brackets. The most significant increase in incidence was in children aged 10 to 14 years. Age-standardized prevalence increased significantly throughout the study period.

CONCLUSION: These results are similar to data from the United States but differ from European data with respect to the annual percent change for incidence as well as age-specific incidence trends. In keeping with the low mortality rates associated with type 1 diabetes, the prevalence continues to rise.