Undiagnosed Pre-diabetes Highly Prevalent in Early Alzheimer’s Disease
July 17, 2013 – A study by a Georgetown neurologist has found that undiagnosed pre-diabetes is much more common than previously thought in people with mild to moderate Alzheimer’s disease.
Dr. R. Scott Turner of Georgetown University Medical Center (GUMC) began enrolling people with mild to moderate Alzheimer’s disease into a nationwide study last year on resveratrol, a compound found in red grapes and red wine.
Resveratrol is thought to act on proteins in the brain in a way that mimics effects of a low-calorie diet, and Turner’s study researches the potential for the compound to change glucose levels in patients with early Alzheimer’s disease (AD).
Turner says he was “shocked” by how many study participants were found to have pre-diabetes.
“We know from animal studies that caloric restriction prevents diseases of aging such as diabetes and Alzheimer’s,” explains Turner, director of the GUMC’s Memory Disorders Program. “On the flip side of the coin, having diabetes increases one’s risk of developing AD. So perhaps by improving glucose tolerance, we will prevent or delay both diabetes and Alzheimer’s.”
To join the resveratrol study, participants were first given a fasting glucose tolerance test to obtain a baseline level, then retested two hours after eating. A high sugar level after two hours reveals glucose intolerance (pre-diabetes) or diabetes if the level is very high.
“The number of people with glucose intolerance (pre-diabetes) was much higher than expected,” says Turner. “I was surprised by how many people didn’t know they were pre-diabetic, and these are individuals who already get the best medical care.”
Alzheimer’s Association Presentation
Of the 125 study participants who completed the two-hour test, 43 percent had pre-diabetes (38 people or 30 percent) while 16 individuals or 13 percent had results consistent with diabetes.
Turner presented his findings at the Alzheimer’s Association International Congress in Boston on July 14.
The Georgetown doctor is now researching whether glucose intolerance or diabetes leads to Alzheimer’s disease, if the inflammation associated with AD triggers glucose intolerance and if a “vicious cycle” of Alzheimer’s and glucose intolerance exists.
A Simple Test
While Turner’s study isn’t designed to answer these questions, his research might provide important clues.
“This result suggests that perhaps we should test all our patients with early Alzheimer’s for glucose intolerance,” he says. “It’s a simple, inexpensive study that reveals critical health information.”
The resveratrol study is sponsored by the Alzheimer’s Disease Cooperative Study through a grant from the National Institute on Aging.