Post-stroke executive function impairments in relation to white matter damage due to stroke lesions versus leukoaraiosis

ImportanceExecutive function impairments are highly prevalent post-stroke and are a feature of vascular dementia. Computed tomography (CT) neuroimaging is routinely acquired in clinical settings. Therefore, determining the prognostic utility of CT-derived markers for post-stroke cognitive outcomes is of key clinical and academic interest. ObjectiveTo determine whether post-stroke executive function is associated with stroke-related white matter damage and/or white matter hypoattenuations of presumed vascular origin (WMHs) on routine CT brain scans. DesignRetrospective cross-sectional analysis of data collected within the Oxford Cognitive Screening (OCS) programme (2016-2020). SettingPatients were recruited at Oxford University Hospitals acute stroke unit. Follow-up cognitive assessment was conducted six-months post-stroke at patients homes. ParticipantsOCS programme recruited a consecutive patient sample with a confirmed diagnosis of stroke, who were minimum 18 years old, able to remain alert for 20 minutes, and able to provide informed consent. This study included all patients who completed six-month follow-up assessment with the Oxford Cognitive Screen-Plus (OCS-Plus) and had a usable acute CT scan with a visible stroke lesion. Main Outcome and MeasuresAssociation between post-stroke executive function and both stroke-specific white matter damage and WMHs on routine CT. Executive function was evaluated using the OCS-Plus Rule Finding task. Stroke lesions were manually delineated on CT, and stroke-related white matter damage was quantified then dichotomised using the HCP-842 atlas. WMHs were visually rated using the Age-Related White Matter Changes scale and dichotomised as present or absent. ResultsAmong 87 stroke patients (mean/SD age = 73.60/11.75; 41 female; 61 ischaemic stroke), multivariable linear regression analyses demonstrated that poorer executive function six-months post-stroke was associated with both stroke damage to the medial lemniscus (B= - 8.86, p< .001, 95% CI [-13.29 -4.43]) and the presence of WMHs (B= -5.42, p= .005, 95% CI [-9.12 -1.72]), after adjusting for covariates including age and education. Conclusions and RelevancePoorer post-stroke executive functioning was associated with both localised patterns of stroke-specific white matter damage and white matter degeneration. Our results confirm the necessary role of white matter integrity for executive functioning post-stroke and highlight the prognostic utility of CT-derived neuroimaging markers for long-term post-stroke cognitive outcomes.