Tract-based disconnection induced by WMH in patients with minor stroke is related to long-term post-stroke cognition

Abstract

AbstractBackgroundOver a third of minor stroke patients will suffer from post-stroke cognitive impairment (PSCI) but there are no validated tools to clearly identify at-risk patients in the early phase. We aimed to investigate the short and long-term cognitive decline using disconnection features from infarct and white matter hyperintensities (WMH) in first-ever minor ischemic stroke patients.MethodsFirst-ever minor ischemic stroke patients (NIHSS≤7) were prospectively followed-up at 72-hour, 6- and 36-month post-stroke with cognitive tests and conventional brain MRI. Infarct and WMH volumes were semi-automatically evaluated on DWI and FLAIR sequences respectively. Bayesian models using tract-based structural disconnection were used to estimate the remote pathological effects of cerebral infarct and/or WMH. The disconnection approach was compared to features extracted from cerebral infarct and WMH volumes and locations. All lesion-based features were compared between patients with and without cognitive impairment at 6- and 36-month post-stroke. The potential association between the features and cognitive domains alterations was assessed by canonical correlation analyses. All statistical analyses were corrected for age, education and multiple comparisons.Results105 patients (female, 31%) with a mean (± SD) age of 63 ± 12 years were enrolled. Infarct volume was 10.28 ± 17.10 cm3 and involved the middle cerebral artery territory in 83% of patients. The burden of WMH was higher within frontal periventricular white matter. Infarct-based features showed no significant relationship with 6 and 36-month PSCI. However, a WMH disconnection factor involving the commissural and frontal tracts was associated with 6- and 36-month PSCI, particularly in executive/attention, language and visuospatial domains. Memory domain alterations were associated with higher WMH burden in right temporal regions.ConclusionsWMH-induced disconnectivity may predict short and long-term PSCI in minor ischemic stroke. These neuroimaging features extracted from routine MR sequences could help identifying at-risk patients to test future rehabilitation interventions.