Washington: A new study conducted in Japan has found that those with diabetes are twice as likely to develop Alzheimer`s and other types of dementia later in life, compared to those having normal blood sugar levels.
Lead researcher Yutaka Kiyohara, MD, PhD, of Kyushu University in Fukuoka, Japan, and his team monitored more than 1,000 men and women over age 60.
The study participants were given a glucose tolerance test after an overnight fast to discover whether they had diabetes.
The participants were then monitored for an average of 11 years and then tested for dementia. The researchers found that 232 participants developed dementia.
They found that 27 percent of the people with diabetes developed dementia, compared with 21 percent of people without diabetes.
That means, people with diabetes were twice as likely to develop dementia, including vascular dementia, which occurs when blood vessels are damaged and eventually deprive the brain of oxygen.
The results remained the same after the researchers accounted for factors such as high blood pressure, high cholesterol and smoking.
The risk of dementia was also higher in people who did not have diabetes, but had impaired glucose tolerance, or were “pre-diabetes.”
In addition, the study found the risk of developing dementia significantly increased when blood sugar was still high two hours after a meal.
“Our findings emphasize the need to consider diabetes as a potential risk factor for dementia,” said Kiyohara.
“Diabetes is a common disorder, and the number of people with it has been growing in recent years all over the world. Controlling diabetes is now more important than ever,” he added.
The study is published in the September 20, 2011, print issue of Neurology.