What is the link between diabetes and AD? by Connie b. Dellobuono
Answer by Connie b. Dellobuono:
The fact that obesity increases the risk of cardiovascular disease and some cancers is well known. But a new Iowa State University study adds to the growing evidence that memory loss should also be a top concern.
The study, published in the Journal of the American Medical Association Neurology, found a strong association between insulin resistance and memory function decline, increasing the risk for Alzheimer's disease. Auriel Willette, a research scientist in the Department of Food Science and Human Nutrition at Iowa State, says insulin resistance is common in people who are obese, pre-diabetic or have Type 2 diabetes.
Willette and co-author Barbara Bendlin, with the Wisconsin Alzheimer's Institute, examined brain scans in 150 late middle-aged adults, who were at risk for Alzheimer's disease, but showed no sign of memory loss. The scans detected if people with higher levels of insulin resistance used less blood sugar in areas of the brain most susceptible to Alzheimer's. When that happens, the brain has less energy to relay information and function, Willette said.
"If you don't have as much fuel, you're not going to be as adept at remembering something or doing something," he said. "This is important with Alzheimer's disease, because over the course of the disease there is a progressive decrease in the amount of blood sugar used in certain brain regions. Those regions end up using less and less."
Willette's work focused on the medial temporal lobe, specifically the hippocampus – a critical region of the brain for learning new things and sending information to long-term memory. It is also one of the areas of the brain that first show massive atrophy or shrinkage due to Alzheimer's disease, Willette said.