“There has been considerable research on stroke in older people, but there is still much to be learned about stroke in younger people and how it affects people of different races and ethnicities,” says Woo, professor in the Department of Neurology and Rehabilitation Medicine at UC and a UC Health physician. “Our study found that even when factors that affect outcomes are accounted for, such as how big the stroke is, race and ethnicity were still independent predictors of how well people would recover.”
This research aligns with UC's strategic direction, Next Lives Here, emphasizing discovery by investigating problems and innovating solutions.
The study involved 418 people with an average age of 43 who all had a bleeding stroke. Of the group, 173 (41%) were black people, 197 (47%) were Latino people and 48 (12%) were white people.
Researchers reviewed brain scans at 42 sites within 19 centers between 2010 and 2015. The scans showed the size of the brain bleed in each person, and researchers evaluated each person’s level of disability three months after stroke. Each person was assigned a score ranging from zero to six based on their level of disability.
Participants were divided into two groups. People in the first group had a score of zero to three, where zero meant no symptoms and three meant they had moderate disability but were able to walk without assistance. People in the second group, the poor outcome group, had a score of four to six, where four meant they had more severe disability and were unable to walk without assistance and six meant they had died.
A total of 52% of the white people were in the poor outcome group, compared to only 35%of the black people and 31% of the Latino people.
When compared to white people, black people had a 58% lower risk of poor outcome and Latino people had a 66% lower risk. The results remained significant after adjusting for age, sex, blood pressure as well as the location and volume of the stroke.
“We examined both the initial size and the expansion of the bleeding in the brain for each participant when they were hospitalized but were not able to find significant evidence that these factors contributed to how well they were doing three months later,” says Woo. “Therefore, these findings may indicate that the differences in outcome between black people, Latino people and white people may be driven more by biological, social and treatment factors related to the risk of bleeding stroke, rather than by differences in early management after admission to the hospital. For example, among our study participants, 8% of white people, or four people, had taken blood thinners prior to their stroke, compared to 4% of black people, or six people, and 1% of Latino people, or two people. Blood thinners are a known risk factor for bleeding stroke. However, these numbers are so small that more research is needed.”
Woo adds that a limitation of the study was that the researchers used broad categories of race and ethnicity, which may not have fully captured the differences among the racial/ethnic subgroups, and that future studies with more detailed information on race/ethnicity subgroups are needed to confirm the findings.
The study was supported by the National Institute of Neurological Disorders and Stroke. Woo cites no conflicts of interest.
Featured photo courtesy of Unsplash.