Prediabetes Linked to Higher Stroke Risk in Study

1. Understanding Stroke Slideshow Pictures
2. Take the Stroke Quiz
3. Atrial Fibrillation Slideshow: Causes, Tests and Treatment

FRIDAY, June 8 (HealthDay News) -- People with higher-than-normal blood sugar levels -- or prediabetes -- may be at greater risk for having a stroke later in life, according to a new review.

Researchers from the University of California warned that this could represent a large-scale health problem, with prediabetes affecting 79 million people in the United States alone.

The study was published online June 7 in the BMJ.

Examining 15 previous studies involving more than 760,000 people, the researchers found that people with prediabetes had a 21 percent higher risk of stroke, according to a journal news release.

Whether a greater risk really exists, however, depended on how prediabetes was measured.

Previously, prediabetes was defined as having a blood sugar (or blood glucose) level of 110 to 125 milligrams per deciliter (mg/dl) following a 12-hour fast.

This definition of prediabetes was set in 1997 by the American Diabetes Association. In 2003, however, the association revised the guidelines to include people with a fasting glucose of 100 to 125mg/dl. Based on this lower limit, the researchers found no increased risk for stroke.

The study authors argued there may be a "threshold effect" and that the risk for stroke may increase at or above a fasting glucose level of 110mg/dl. They noted that the quality of evidence was variable and that other factors also may come into play.

They concluded that people with prediabetes or a fasting glucose level of 110 to 125mg/dl had a "modestly higher risk of future stroke," and that people with this condition should keep their weight under control and adopt a healthier lifestyle to reduce the risk.

In an accompanying journal editorial, Jonathan Treadwell, a senior research analyst with the ECRI Institute, a nonprofit patient-care research organization, said the researchers used a simplified classification of prediabetes, and that it's impossible to know the exact scope of the potential association between prediabetes and stroke.

-- Mary Elizabeth Dallas

Copyright © 2012 HealthDay. All rights reserved.

SOURCE: BMJ, news release, June 6, 2012