Diabetes and Brain Health

 

Diabetes Can Impact Cognitive Health

Type 2 diabetes (T2DM) has reached epidemic levels, posing a significant challenge to both society and healthcare systems. Advances in diabetes care and treatment mean that more people are being diagnosed with T2DM and living longer. However, as the population with T2DM ages, cognitive impairment is becoming an increasingly prevalent issue. Managing diabetes effectively requires complex cognitive skills, making cognitive decline a serious obstacle to self-care and treatment adherence. Adding to this concern, T2DM itself is a known risk factor for cognitive impairment and Alzheimer's disease (AD).

Why Diabetes Raises Dementia Risk

A 2022 review and meta-analysis confirmed that people with type 2 diabetes carry a significantly higher risk of developing Alzheimer's disease than those without it (Athanasaki et al., 2022). The connection isn't fully explained by cerebrovascular disease alone — insulin resistance, chronic inflammation, and impaired glucose metabolism in the brain itself all appear to contribute, compounding the vascular damage diabetes does elsewhere in the body. People with T2DM represent an at-risk group for dementia, making them an important focus for both primary and secondary prevention efforts.

The Awareness Gap Is Real — We've Measured It

It's one thing to say that people underestimate diabetes's effect on the brain; we set out to measure it. In a cross-sectional study of people with diabetes and the general public in Ireland, we found a clear gap between how well people understood diabetes's impact on the eyes, heart and kidneys, and how little they understood about its impact on the brain — despite the risk being just as real (Dolan et al., 2018). In a related review, we argued that closing this gap means building brain health into everyday diabetes care rather than treating it as a separate concern: cognitive screening as part of standard diabetes review, closer attention to glycaemic control in older patients, and clearer conversations with patients about why the brain, not just the eyes, kidneys and heart, belongs on the list of things diabetes affects (Dolan, McHugh & Lawlor, 2016).

What You Can Do

The good news is that diabetes is one of the 14 major modifiable risk factors for dementia — meaning the same steps that manage diabetes well also protect the brain. Keeping blood sugar, blood pressure, and cholesterol within target range, staying physically active, and attending regular reviews all reduce cognitive risk alongside the more familiar benefits to heart and kidney health. Brain Health Chronicles seeks to bridge the awareness gap our own research identified, empowering individuals with T2DM to better understand and proactively address their modifiable brain health risks.

References

Athanasaki, A., Melanis, K., Tsantzali, I., et al. (2022). Type 2 Diabetes Mellitus as a Risk Factor for Alzheimer's Disease: Review and Meta-Analysis. Biomedicines, 10(4), 778. https://doi.org/10.3390/biomedicines10040778

Dolan, C., Glynn, R., Griffin, S., Conroy, C., Loftus, C., Wiehe, P. C., Healy, M. L., & Lawlor, B. (2018). Brain complications of diabetes mellitus: a cross-sectional study of awareness among individuals with diabetes and the general population in Ireland. Diabetic Medicine, 35(7), 871–879.

Dolan, C., McHugh, J. E., & Lawlor, B. A. (2016). Diabetes and brain health: implications for practice. Irish Journal of Psychological Medicine, 33(3), 179–191.