People suffering from diabetes for 10 years or more face triple the risk of stroke, compared to non-diabetics, says a new study. This is the first study to examine whether the length of time a man or woman has type 2 diabetes impacts the risk of ischemic stroke, which is the commonest type of stroke caused by blocked blood flow to the brain.
“The findings emphasize the chronic nature of diabetes and the fact that it damages the blood vessels over time,” said Mitchell S.V. Elkind, senior study author from the Columbia University Medical Center, New York City, the journal Stroke reported.
“Although stroke rates have been declining overall, the increase in diabetes incidence over the same period may lead to a higher overall stroke burden in the future,” said Elkind, also associate chairman of neurology for clinical research and training at Columbia.
As part of the Northern Manhattan Study (NOMAS), researchers followed 3,298 people (average age 69) who had never had a stroke, according to a university statement.
Nearly 22 percent of participants had type 2 diabetes at the start of the study. After an average nine years of follow-up, an additional 10 percent developed diabetes.
After considering other factors such as age, smoking history, physical activity, history of heart disease, blood pressure and cholesterol, researchers said that compared to people without diabetes, the risk of stroke increased 70 percent in people with diabetes for less than five years; 80 percent in people with diabetes for five to 10 years; and three-fold in people with diabetes for 10 years or more.
For people with diabetes, stroke risk may depend as much on how long you’ve had the condition as on the diagnosis itself, Elkind said.
Among the nearly 26 million Americans with diabetes, more than half are younger than 65, according to the American Diabetes Association.