Patterns in the Incidence (1994–2018) and Prevalence (2004–2018) of Type 1 and Type 2 Diabetes Among Nova Scotian Youth Under 20 Years of Age

OBJECTIVES: Rates of type 1 and type 2 diabetes (T1D and T2D, respectively) in youth may be increasing globally, but findings vary across populations. We aimed to determine changes in incidence and prevalence of T1D and T2D over a 25-year period (1994-2018) in youth <20 years of age in Nova Scotia (NS). METHODS: This population-based descriptive epidemiologic study used the Diabetes Care Program of the NS Registry that prospectively collects population-based records for all cases of diabetes in youth. Incidence (1994-2018) and prevalence (2004-2018) of T1D and T2D were calculated per 100,000 for 5-year periods using national census population estimates (0-19 years) and analyzed by sex, age group, and rural vs urban residence. RESULTS: Incidence (95% confidence interval [CI]) of T1D rose from 26.4 (23.0-29.7) in 1994-1998 to 37.9 (33.3-42.6) in 2014-2018 in 0-14-year-olds. The average annual increase was 0.7 (0.43-0.97) per 100,000. Incidence appeared to plateau after 2008, except in 10-14-year-olds, where it continued to rise. Prevalence (95% CI) of T1D for youth 0-19 years of age increased from 288.4 (278.2-298.6) per 100,000 in 2004-2008 to 333.4 (321.7-345.1) in 2014-2018. Incidence of T2D in 10-19-year-olds rose from 2.9 per 100,000 in 1994-1998 to 13.0 per 100,000 in 2014-2018 and was higher in females and youth living in rural areas. CONCLUSIONS: Incidence of both types of diabetes in NS is high and continuing to rise. Patterns in T1D incidence align with those reported in other high-incidence populations. Incidence and prevalence of T2D in NS youth were similar to or higher than most previous reports despite the lower ethnic diversity in NS compared with other high-incidence populations.