Blood-Brain Barrier Disruption in People With White Matter Hyperintensities Who Have Had a Stroke

Objective: To follow a cohort of stroke patients with white matter hyperintensities (WMH), using MRI, and thereby track the natural history of changes in blood-brain barrier (BBB) disruption. By establishing a better understanding of the relationship between the presence of BBB disruption and WMH progression, we hope to identify BBB permeability on MRI as a biomarker for disease pathogenesis, disease activity, and disease progression. Study Population: Stroke patients will be eligible for this study if their MRI shows evidence of confluent WMH on FLAIR imaging (Fazekas score 2 or greater), obtain a six-item screener score greater than 3, and have no other diagnosis to explain the finding (e.g. multiple sclerosis). The NIH stroke service currently evaluates 600 patients a year with MRI. Approximately 20% have confluent WMH on their FLAIR MRI and would meet the inclusion criteria for this study. Thus, the cohort for this study will be recruited from the population evaluated by the NIH stroke service. Design: Patients with a clinical or radiographic history of stroke will be eligible for enrollment. Enrolled subjects who meet the inclusion/exclusion criteria will be followed serially with MRI. Research procedures will consist of an MRI, interval history and cognitive/clinical scaling. Research procedures will occur every 3 months for the first year, every 6 months for the second year, and then yearly thereafter for a total of 6 years or untill the study has ended. Outcome measures: Using a previously described and independently validated method, BBB permeability will be assessed at each research time point as will WMH burden. The presence of BBB will be compared with progression of WMH into normal appearing white matter (NAWM). The primary outcome is the relationship between BBB disruption and WMH progression. It is postulated that BBB disruption in the NAWM will be associated with progression of the WMH. Secondary outcomes will examine the spatial relationship between BBB disruption and WMH progression and changes in cognitive scaling. Additionally, other exploratory MRI biomarkers for disease progression will be examined (e.g. susceptibility weighted imaging with 7T MRI to examine regions of known BBB disruption).