As of 2014, approximately 9.3% of the population (29.1 million people) have either Type 1 or Type 2 diabetes in the United States (1). With the growing epidemic of diabetes and the increase in the number of people that live to old age, it is essential to determine the long-term effects of how diabetes impacts physiological structure and function. It has long been understood that diabetes can cause damage to the eyes, kidneys, and heart. Less often talked about is the effect of diabetes on the brain.

A Brief History

Diabetes has been known to have an effect on the brain for over 100 years. In the early 1900’s, researchers and clinicians found that diabetic patients often complained of poor memory and attention span (2). In 1950, the term diabetic encephalopathy was introduced to describe central nervous system-related complications of diabetes, and more recently, the term diabetes-associated
cognitive decline (DACD) has been used to describe diabetes-related reductions in cognitive function (2).

Several studies have shown that cognitive decline is associated with both type 1 and type 2 diabetes. As type 1 diabetes is typically diagnosed during childhood, there are concerns that the “peaks and valleys” of blood sugar can have detrimental effects during the period of rapid development and growth in the central nervous system (3]). In type 2 diabetes, declines in cognitive function have been associated with the length of time with the disease as well as poor control over blood sugars levels (4).

Current Research

A new study published in Neurology describes that the reason diabetes can result in cognitive decline and altered ability to perform daily activities may be related to changes in blood vessel activity in
the brain (5). A group of adults aged 65 or older were followed for a 2 year period; the diabetic patients had generally lower scores on cognitive tests when compared to those without diabetes. 

According to this study, the flexibility of blood vessels declined in diabetic patients while it remained the same for healthy individuals. In healthy patients, flexible vessels slightly swell thereby increasing blood flow and oxygen to areas that are more active.  However, diabetes can cause vessels to become less pliable and responsive in the brain. These changes occurred even in patients that were taking diabetes medication and had their blood sugars under control.

What Does this Mean?

New medications may be needed to improve blood vessel flexibility in diabetics in order to delay or prevent cognitive decline. As rates of diabetes continue to increase, further research is needed to determine what sort of therapies are required to combat the possibility of detrimental effects of diabetes on the brain. Additionally, because the brain is less often indicated as an organ at risk in diabetes, increased awareness to clinicians and patients will also increase the understanding and treatment of the disease. Understanding the risks of diabetes is important for anyone who lives with this condition as nutritional management is an essential component of care. Remember to always
speak with a dietitian and endocrinologist about managing your wellness plan.

Happy Eating!

Samantha Mogil, Nutrition Intern