Diabetes May Be a Risk Factor for Alzheimer’sAngie Godinez
The Wall Street Journal recently reported that two recent studies show blood-sugar levels can affect the brain—-adding new evidence that diabetes might be a significant risk factor for developing Alzheimer’s disease and other forms of dementia.
Researchers at Washington University in St. Louis found in a study of mice that raising blood sugar to abnormally high levels corresponded with increased production in the brain of amyloid beta, a protein thought to be an important factor in Alzheimer’s disease. In a separate study of middle-aged people, conducted at the University of Pittsburgh, those with Type 1 diabetes had significantly more brain lesions, and slower cognitive function, than people without the disease.
Neither study is definitive and more research is needed. Still, doctors say the results underscore the need for people with diabetes to closely control their blood sugar and keep it within healthy ranges.
For people with Type 2 diabetes, exercise represents a promising way to reduce the risk of Alzheimer’s, says Suzanne Craft, professor of gerontology and geriatric medicine at Wake Forest Baptist Medical Center. Exercise directs the body to more efficiently metabolize insulin. Insulin also is thought to help protect the brain against amyloid and improve connectivity between neurons and memory formation, she says.
Diabetes, a condition where the body is unable to effectively break down blood sugar, affects some 29 million people in the U.S. and can cause heart disease, blindness and death. Type 2 diabetes, the most common form, occurs when the body becomes desensitized to insulin, a naturally occurring hormone that metabolizes sugar. Type 1 diabetes, which typically surfaces during childhood, occurs in people whose bodies don’t produce enough insulin to begin with.
Alzheimer’s disease is still poorly understood and there are multiple risk factors that contribute to dementia, including genetics and age. Most people with diabetes won’t go on to develop Alzheimer’s disease and are able to live healthy, fully functional lives.
“If we prematurely equate diabetes with a condition as severe as dementia or Alzheimer’s, we’d be doing a great disservice to the 29 million people in this country who hold complex positions and fulfill complex job requirements,” says Samuel Dagogo-Jack, a diabetes specialist and professor of medicine at the University of Tennessee Health Science Center.
The University of Pittsburgh study, of roughly 180 middle-aged people, found that Type 1 diabetics had significantly more brain lesions called white matter hyperintensities than people without diabetes, and performed more poorly on cognitive function tests. Caterina Rosano, a lead researcher in the study, said she was surprised by the findings because the study participants were so young: The diabetic group had an average age of 50 and the nondiabetic group had an average of 48, suggesting uncontrolled blood sugar is having a negative impact on the brain years or even decades before symptoms of dementia start to appear.