UAB Media Relations

Some 18 percent of adults with no documented history of stroke report having had one or more stroke symptoms such as sudden numbness or weakness on one side of the body, according to a study by UAB researchers published in the Oct. 9 issue of Archives of Internal Medicine.

UAB epidemiologist and lead author Virginia J. Howard, M.S.P.H., and colleagues, showed that people with more stroke risk factors (such as high blood pressure, diabetes and smoking), African-Americans, and those with lower income, less education, and poorer health status were more likely to have one or more stroke symptoms. This suggests that many of these reported stroke symptoms might have been small strokes that went undiagnosed.

Data came from a study funded by the National Institute of Neurological Disorders and Stroke, the REasons for Geographic And Racial Differences in Stroke (REGARDS) study, a national sample of the general population with oversampling in the so-called “stroke belt” that includes eight Southeastern U.S. states.

The researchers assessed a random sample of 18,462 adults older than 45 years - average age 65.8 - who had not been diagnosed with stroke. The sample incorporated those considered at risk for stroke, including 7,567 African-Americans (41 percent of the total sample, a higher ratio than in the general population) and 6,534 (35.4 percent of the sample) residents of the stroke belt.”

In telephone interviews conducted from January 2003 to November 2005, participants provided information about demographics, general quality of life and medical history, including whether a physician had ever told them that they had a stroke and whether they had experienced the sudden onset of any of six classic stroke symptoms. Brief physical examinations were conducted three to four weeks later. A stroke risk score was calculated for each individual based on demographics, behaviors and other risk factors, with higher scores indicating a greater risk for stroke.

A total of 3,292, or 17.8 percent, of the participants reported having had one or more stroke symptoms. Of this group, 8.5 percent reported sudden numbness on one side of the body; 5.8 percent reported sudden weakness on one side of the body; 4.6 percent reported sudden vision loss in one or both eyes; 2.7 percent reported sudden loss of the ability to understand what others were saying; and 3.8 percent reported the sudden inability to express themselves in speech or writing.

Because awareness of stroke symptoms is low, Howard, who is on the faculty of the UAB School of Public Health, said it is possible that these individuals did not recognize their symptoms as that of a stroke or that the symptoms did not reach the threshold necessary for a stroke diagnosis.

“Targeted education on the warning signs of stroke and risk factor reduction efforts for individuals who report stroke symptoms may be helpful in improving early recognition and in the prevention of stroke, as these otherwise unrecognized events could have a substantial impact on cognitive functioning or personality and could also be powerful indicators of future major stroke events,” Howard said.