A new study published in the Journal of the American Medical Association Neurology suggests there is a link between insulin resistance (IR) and memory loss, increasing the risk of Alzheimer’s disease.
Researchers from Iowa State University state that insulin resistance is common in people who are overweight/obese, pre-diabetic or have type 2 diabetes. They examined brain scans from 150 late middle-aged adults. Participants underwent cognitive testing and had their blood drawn. Almost 70% of participants had parental history of Alzheimer’s and about 40% had a specific gene linked to an increased risk of insulin resistance.
Findings revealed that those with increased IR had reduced blood sugars in certain areas of the brain that affected memory function—which is also linked to Alzheimer’s. Therefore late middle-aged adults with IR are at increased risk for developing Alzheimer’s.
“If you don’t have as much fuel, you’re not going to be as adept at remembering something or doing something,” lead author Willette stated. “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.”
Previous studies have demonstrated that older adults with IR, high blood sugars, and type 2 diabetes are more likely to have reduced glucose metabolism and are at increased risk for developing dementia. Post-mortem examinations have confirmed these findings.
Researchers conclude that further research should encompass the understanding of insulin signaling in the brain among at-risk healthy individuals.
Sources for Today’s Article:
“Insulin resistance increases risk for Alzheimer’s disease, study finds,” ScienceDaily web site July 27, 2015; www.sciencedaily.com/releases/2015/07/150727130816.htm.
Willette, A.A., et al., “Association of insulin resistance with cerebral glucose uptake in late middle–aged adults at risk for Alzheimer disease,†JAMA Neurology 2015; DOI:10.1001/jamaneurol.2015.0613.