Insulin-dependent diabetes linked to sharply higher dementia risk

Individuals with diabetes are at an increased risk of developing dementia but those with insulin-requiring type 2 diabetes and type 1 diabetes have the greatest risk, according to research presented at the 28th European Congress of Endocrinology in Prague. Specifically, these higher-risk individuals were over twice as likely to develop the neurological disease. The findings suggest that dementia risk is not the same for all types of diabetes and future prevention strategies, such as continuous glucose monitoring, should be implemented in routine diabetes management.

In this study, researchers from Kyung Hee University Hospital at Gangdong and Samsung Medical Center examined over 1.3 million adults in South Korea, aged 40 and older, without dementia, and grouped them according to their diabetes status: no diabetes, type 2 diabetes using oral anti-diabetic medications, type 2 diabetes using insulin and type 1 diabetes. They followed the individuals from 2013 to 2024, or until a diagnosis of dementia, and found that those with diabetes had a higher risk of developing dementia compared to those without diabetes.

In particular, those with type 2 diabetes taking oral anti-diabetic medications were almost 1.3 times more likely to develop dementia, while the rate of dementia onset was 2.1 times as great among those with type 2 diabetes taking insulin and 2.4 times more in those with type 1 diabetes. Similar trends were observed for Alzheimer's disease and vascular dementia.

"This is surprising because it suggests that not all types of diabetes carries the same risk, and that people with more intensive or insulin-dependent treatment may be particularly vulnerable to cognitive decline," said lead author, Professor Ji Eun Jun from Kyung Hee University Hospital at Gangdong. Professor Jun added: "Recognising diabetes as a potential risk factor for brain health and not just a metabolic condition could help identify a group of patients who may benefit from earlier monitoring for cognitive decline. Improving long-term glucose control and reducing large fluctuations in glucose levels could play a role in lowering dementia risk."