Memory problems may be sign of stroke risk

"Finding ways to prevent stroke and identify people at risk for stroke are important public health problems," said study author Abraham J. Letter of the University of Alabama at Birmingham. "This study shows we might get a better idea of who is at high risk of stroke by including a couple simple tests when we are evaluating people who already have some stroke risk."

For the study, researchers gave tests to people age 45 and older who had never had a stroke, then contacted them twice a year by phone for up to 4.5 years to determine whether they had suffered a stroke. The average age of the participants was 67. Strokes were then confirmed by medical records. A total of 14,842 people took a verbal fluency test, measuring the brain's executive functioning skills, and 17,851 people took a word recall memory test.

The study was part of a larger study called the REasons for Geographic and Racial Differences in Stroke (REGARDS) study. During the study, 123 participants who had taken the verbal fluency test and 129 participants who had taken the memory test experienced a stroke.

Those who scored in the bottom 20 percent for verbal fluency were 3.6 times more likely to develop a stroke than those who scored in the top 20 percent. For the memory test, those who scored in the bottom 20 percent were 3.5 times more likely to have a stroke than those in the top 20 percent. The difference in stroke incidence rates between those with the bottom and top 20 percent of scores was 3.3 strokes per thousand person-years. In general, the differences remained after researchers adjusted for age, education, race and where participants lived.

At age 50, those who scored in the bottom 20 percent of the memory test were 9.4 times more likely to later have a stroke than those in the top 20 percent, but the difference was not as large at older ages.

The study was supported by the National Institutes of Health and the National Institute of Neurological Disorders and Stroke.