Patterns in the incidence (1994-2018) and prevalence (2004-2018) of type 1 and type 2 diabetes among Nova Scotian youth under 20 years.

Abstract

Aims: Rates of type 1(T1D) and type 2(T2D) diabetes in youth may be increasing globally; however, 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 under age 20 in Nova Scotia(NS).

Methods: This population-based descriptive epidemiologic study used the Diabetes Care Program of 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(0-19yr) and analysed by sex, age group and rural vs urban residence.

Results: Incidence (95% 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 ages 0-19 years increased from 288.4(278.2-298.6) per 100,000 in 2004-2008 to 333.4(321.7-345.1) in 2014-18. 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 was similar to, or higher than, most previous reports despite the lower ethnic diversity in NS compared to other high incidence populations.