Type 2 diabetes in dementia and Alzheimer’s disease: Intertwined global health issues brewing on the horizon

Type 2 diabetes continues to grow in prevalence globally due to contemporary dietary patterns and physical inactivity. Among its multiple complications, neurological injury is a long-known consequence of diabetes, especially in the peripheral nerve as diabetic peripheral neuropathy. However, the adverse effects of diabetes on brain health are also increasingly appreciated, raising patients’ risk of developing cognitive impairment and eventual dementia along with brain structural changes. Thus, despite the highly heritable nature of Alzheimer’s disease, addressing modifiable risk factors, including type 2 diabetes, may help curb dementia development. This review covers epidemiological evidence for the link between diabetes and dementia as well as mechanistic evidence on similar underlying pathophysiological pathways, describing potential links between the two diseases. Given excess dementia risk from diabetes, this review also covers how optimal diabetes control and, ideally, diabetes prevention, may mitigate future dementia burden, concluding with some practical interventions.