Researchers and clinicians have found that uncontrolled diabetes may increase the risk of experiencing cognitive problems, such as memory loss. Higher than normal blood glucose (sugar) levels can damage nerve cells, supportive glial cells, and blood vessels in both peripheral nerves of the body and the brain.

Research has shown that having Type 2 diabetes may double the risk of developing a slowly progressive dementia. And while there are many causes of dementia, including Alzheimer’s disease and stroke, it is also possible that diabetes may cause memory loss through silent damage to the capillaries (tiny blood vessels that form the network for glucose and oxygen exchange between blood vessels and tissue cells).

Research has shown that having Type 2 diabetes may double the risk of developing a slowly progressive dementia. And while there are many causes of dementia, including Alzheimer’s disease and stroke, it is also possible that diabetes may cause memory loss through silent damage to the capillaries (tiny blood vessels that form the network for glucose and oxygen exchange between blood vessels and tissue cells).

“While it is relatively easy to measure glucose and insulin in the blood, we hardly ever measure glucose and insulin in the brain. This leaves us with critical questions about how diabetes and pre-diabetes may be affecting the brain,” says Helena Chang Chui, MD, chair and professor of neurology and principal investigator of the USC Healthier Vessels, Healthier Brain Study. Her research examines how glucose and insulin may be affecting the brain, as well as how the health of blood vessels may impact memory.

Dr. Chui’s research examines the causes of memory loss from a new and important research angles. She describes the complexities of researching the relationship between diabetes and memory loss, “While it is relatively easy to measure brain shrinkage (atrophy), Magnetic Resonance Imaging (MRI) scans and CAT scans cannot show plaques and tangles, which are the microscopic hallmarks of Alzheimer’s disease, or damage to capillaries that can result from diabetes.”

The research team at the USC Healthier Vessels, Healthier Brain Study are working to better understand how blood sugar levels and the body’s ability to absorb and use glucose and/or insulin affects capillaries, brain cells, and memory function.

“USC is the home to the Stevens Institute of Neuroimaging and Informatics,” explains Dr. Chui. “We are able to perform state of the art, high resolution MRI images of the brain and blood vessels. We have developed a new method of assessing capillary integrity using contrast MRI. We can also measure hundreds of proteins, including insulin, insulin growth factor, beta-amyloid, tau proteins, omega-3-fatty acids from samples of cerebrospinal fluid (CSF, using an optional lumbar puncture).” This comprehensive study is ground-breaking research in the field of memory and dementia and will follow people over 3 years. People over 60 years of age who are pre-diabetic or diabetic may be eligible to participate. Additionally, to better understand the influence of blood vessels the study includes people with high blood pressure and high cholesterol.

If you are older, speak English or Spanish, and have: pre-diabetes, diabetes, high blood pressure or high cholesterol, you may qualify for the study.

If you are interested in participating in the study or would like more information, please visit http://adrc.usc.edu/Healthier-Brain-Study.

By Tara Rose, PhD