A recent study conducted by a team of researchers, led by Sook-Lei Liew, PhD, from USC’s Mark and Mary Stevens Neuroimaging and Informatics Institute (Stevens INI), has revealed that areas of age-related damage in the brain are connected to motor outcomes after a stroke. The findings from this study, published in Neurology®, suggest that damage to the corticospinal tract (CST) is not the only factor influencing stroke recovery, indicating that white matter hyperintensities (WMHs) may play a role in motor impairment post-stroke. WMHs are areas of age-related damage in the brain’s white matter, typically associated with vascular dysfunction and cognitive issues. The ENIGMA Stroke Recovery working group, funded by the National Institute of Neurological Disorders and Stroke (NINDS), aims to investigate how brain changes post-stroke impact recovery and functional outcomes. This research collaboration includes data from over 2,100 stroke patients across 65 research studies and 10 countries, making it the most extensive multisite retrospective stroke data collaboration to date.
The study examined data from 223 stroke patients in four countries and found that larger WMH volumes were linked to more severe motor impairment after a stroke, regardless of CST damage. WMHs are known to be associated with conditions such as hypertension, diabetes, high cholesterol, and smoking, and have primarily been studied in relation to cognitive impairment rather than motor impairment post-stroke. Interestingly, the relationship between CST damage and motor impairment varied based on the severity of WMHs, with patients exhibiting mild WMHs showing a typical relationship between CST damage and motor impairment, while those with moderate to severe WMHs did not show this relationship. Instead, motor impairment was correlated with WMH volume rather than CST damage. These findings suggest that WMHs could provide additional context for predicting stroke recovery, potentially improving predictive models for post-stroke rehabilitation.
The study’s lead author, Jennifer K. Ferris, PhD, from Simon Fraser University and the BC Centre for Disease Control, highlights the importance of assessing age-related brain health factors, such as WMH volume, in predicting stroke recovery. By incorporating assessments of overall brain health and cardiovascular factors, researchers may be able to better predict an individual’s potential for recovery post-stroke, leading to personalized rehabilitation strategies that could enhance outcomes. The research team plans to conduct longitudinal studies to validate their findings, paving the way for the development of more accurate markers for recovery that could revolutionize post-stroke care and rehabilitation.
Arthur W. Toga, PhD, Director of Stevens INI, emphasizes the significance of Dr. Liew and her team’s work in advancing stroke research through innovative imaging technologies. Stroke remains a leading cause of long-term disability, with significant public health implications. Studies such as this one aim to usher in a new era of precision rehabilitation by utilizing data-driven decision-making based on brain imaging and other noninvasive measures to tailor personalized rehabilitation strategies. The ultimate goal is to improve outcomes for stroke survivors by identifying specific factors, such as WMH volume, that can enhance predictive models for stroke recovery and rehabilitation, offering hope for a more targeted and effective approach to post-stroke care.
