People with pre-diabetes may have an increased risk of stroke. However, the link between pre-diabetes and stroke may depend on how pre-diabetes is defined.
"Eat healthy and exercise to prevent diabetes and heart disease."
Type 2 diabetes patients face a higher risk of heart-related problems such as high blood pressure and high cholesterol. Pre-diabetes also increases the risk for these health problems. But researchers are still unclear about the impact of pre-diabetes on stroke risk.
So Bruce Ovbiagele, MD, of the University of California, San Diego, and colleagues set out to study the relationship between pre-diabetes and the risk of stroke.
They found that pre-diabetes can increase the stroke, but only when pre-diabetes is defined a certain way.
In 1997, the American Diabetes Association (ADA) defined pre-diabetes as a fasting blood glucose (blood sugar levels after not eating) as 110 to 125 mg/dL.
When Dr. Ovbiagele and colleagues used this 1997 definition of pre-diabetes, they found that pre-diabetes was associated with a 21 percent increased risk of stroke.
When the researchers defined pre-diabetes using the 2003 ADA definition (100 to 125 mg/dL), they found no increased risk of stroke.
These findings suggest that there may be a point at which fasting blood sugar levels start to boost the future risk of stroke. That is, the risk of stroke for people with pre-diabetes may begin at a fasting blood sugar level of 110 mg/dL.
The authors note that other factors that were not measured in the study may be responsible for these varied results.
Still, the authors write that "people with pre-diabetes should be aware that they are at increased risk of future stroke."
They add that pre-diabetes not only increases the risk of stroke, but also for other cardiovascular problems.
"For people with pre-diabetes, weight loss in conjunction with healthy lifestyle changes is associated with decreased risk of transitioning to frank diabetes and may even reduce future stroke events," they write.
For the study, Dr. Ovbiagele and colleagues examined the results of 15 studies including more than 760,000 participants.
The results are published in the British Medical Journal (BMJ).