new studies suggest diabetes increases the risk of Alzheimer’s disease. According to Grady this is a daunting prospect:Denise Grady of The New York Times reports
The connection raises an ominous prospect: that increases in diabetes, a major concern in the United States and worldwide, may worsen the rising toll from Alzheimer’s. The findings also add dementia to the cloud of threats that already hang over people with diabetes, including heart disease, strokes, kidney failure, blindness and amputations.Grady explains there are a number of ways diabetes detrimentally affects brain function:
Not everyone with diabetes gets Alzheimer’s, and not all Alzheimer’s patients are diabetic. But in the past decade, several large studies have found that compared with healthy people of the same age and sex, those with Type 2 diabetes are twice as likely to develop Alzheimer’s. The reason is not known, but researchers initially suspected that cardiovascular problems caused by diabetes might contribute to dementia by blocking blood flow to the brain or causing strokes.Dr. Rachel A. Whitmer of the Division of Research at Kaiser Permanente in Oakland, California believes this link does not bode well for our future:
More recently, though, scientists have begun to think that the diseases are connected in other ways as well. In both, destructive deposits of amyloid, a type of protein, build up: in the brain in Alzheimer’s, in the pancreas in Type 2 diabetes.
People with Type 2 often have a condition called insulin resistance, in which their cells cannot properly use insulin, the hormone needed to help glucose leave the blood and enter cells that need it. To compensate, the pancreas makes extra insulin, which can reach high levels in the blood. Too much insulin may lead to inflammation, which can contribute to damage in the brain.
In addition, abnormalities in glucose metabolism and insulin levels in the brain itself may be harmful. Some research has found that too much insulin in the brain can contribute to amyloid buildup. Researchers have even suggested that Alzheimer’s disease may actually be “Type 3 diabetes,” a form of the disease affecting the nervous system.
“With the whole diabetes epidemic we’re seeing much more Type 2, so are we going to see even more Alzheimer’s than we thought we would see? If we continue in this direction, it’s a little bit frightening.”