By Robert Preidt
University of Michigan researchers analyzed national data from more than 4,900 black and white Americans aged 65 and older who underwent tests of memory and thinking speed between 1998 and 2012.
Test results among those who suffered a stroke fell as much as if they had suddenly aged 7.9 years, according to the study in the July issue of the journal Stroke.
Stroke had a similar effect on brain function in both blacks and whites in the study. But previous research has found that rates of memory and thinking problems in older blacks are generally twice that of whites.
These new findings show that stroke doesn't account for that racial disparity as people age, and also highlight the importance of stroke prevention, the researchers said.
"As we search for the key drivers of the known disparities in cognitive [mental] decline between blacks and whites, we focus here on the role of 'health shocks' such as stroke," study author Dr. Deborah Levine, an assistant professor in the University of Michigan medical school, said in a university news release.
"Although we found that stroke does not explain the difference, these results show the amount of cognitive aging that stroke brings on, and therefore the importance of stroke prevention to reduce the risk of cognitive decline," she added.