Exposure to Gestational Diabetes Mellitus: Impact on the Development of Early-Onset Type 2 Diabetes in Canadian First Nations and Non-First Nations Offspring

Type 2 diabetes is increasing in children worldwide, with Canadian First Nations (FN) children disproportionally affected. The prevalence of gestational diabetes mellitus (GDM) also is increasing. The objective of this study was to evaluate the impact of GDM exposure in utero and FN status on the subsequent risk of type 2 diabetes in offspring in the first 30 years of life. In this population-based historical prospective cohort study, we used administrative databases linked to a clinical database to explore the independent association and interaction between GDM and FN status on the subsequent development of type 2 diabetes in offspring. Among 321,008 births with a median follow-up of 15.1 years, both maternal GDM and FN status were independently associated with subsequent risk of type 2 diabetes in offspring in the first 30 years of life (hazard ratio 3.03 [95% CI 2.44-3.76; P < 0.0001] vs. 4.86 [95% CI 4.08-5.79; P < 0.0001], respectively). No interaction between GDM and FN status on type 2 diabetes risk was observed. FN status had a stronger impact on the development of type 2 diabetes in offspring than GDM. GDM is an important modifiable risk factor for type 2 diabetes, and its prevention may reduce the prevalence of subsequent type 2 diabetes in offspring. This study adds unique and rigorous evidence to the global public health debate about the impact of GDM on the long-term health of offspring.