A Possible Link between Diabetes and Dementia
At the BCAT Research Center, we have been focusing a lot on co-morbid medical conditions in patients with dementia. Part of our effort is in creating positive preventive strategies that could lower or mitigate dementia risk. We believe that a number of metabolic conditions are key to the development of some dementia syndromes. One possible link is Type 2 diabetes and dementia. Three facts to keep in mind: (1) Type 2 diabetes is far more prevalent than Type 1 diabetes (juvenile diabetes); (2) in a general sense, Type 2, which typically develops in adulthood, can be the result of poor life habits, significantly associated with obesity, poor diet, lack of exercise, etc.; (3) persons with Type 2 are seven times more likely to develop some form of dementia than persons without diabetes.
For at least 3 decades, researchers shave explored possible negative health outcomes caused by, or associated with diabetes. In Type 2, persons typically have what is described as “insulin resistant” conditions. They tend to mass produce insulin as a response to the body not sufficiently using available insulin to break down sugars. At the same time, the body produces an enzyme to break insulin down. That is, where there is insulin, there is a substance called insulin degrading enzyme (IDE).
Here’s where it gets interesting. IDE not only regulates insulin levels, but also appears to break down beta amyloid, one of the proteins associated with Alzheimer’s disease (AD). It may be the case that IDE is an important regulator of beta amyloid. However, it appear that IDE preferentially regulates insulin over beta amyloid. So, if the body is producing more insulin, then IDE may be concentrated in degrading insulin at the expense of beta amyloid regulation. This may result in an accumulation of beta amyloid, especially in the hippocampus, which presumably is a trigger for AD.
In some people, brain insulin resistance is a whole-body disease (like in Type 2 diabetes). However, it may be the case that for other people, it is limited to the brain. For the latter group, they can be said to have Type 3 diabetes. Both forms have real-life risk consequences for patients, increasing the likelihood of developing dementia. This is why it is important to practice healthy life habits. This is a natural way to lower dementia risk and promote positive health.
It really is the case that when people take responsibility for their health, they lower their risk for disease. We continue to advocate for brain-healthy habits like cognitive stimulation, physical exercise, sufficient sleep, proper diet, and healthy weight control as preventative measures all of us can practice.