Abstract P71: Global Blood-Brain Barrier Disruption After Acute Stroke

Background: Acute ischemia is known to cause local disruption of the blood-brain barrier (BBB), but studies have also shown that BBB disruption can be detected remote from the acute lesion. We sought to test a whole brain measurement of BBB disruption. Methods: This is a retrospective analysis of a deidentified dataset of stroke patients who did not undergo thrombolysis or thrombectomy and had an MRI performed with perfusion weighted imaging (PWI) 4-24 hours after symptom onset. We used PWI source images to identify voxels that demonstrated gadolinium leakage during the acquisition. BBB disruption was defined as a >1% change in signal due to leakage compared with normal tissue. Voxels that did not demonstrate adequate bolus tracking where excluded as noise. This yielded a whole brain average of voxels demonstrating BBB disruption that was not due to noise (wbBBB). We examined age, sex, NIHSS, Fazekas score, and time from onset as predictors of wbBBB using linear regression (continuous variables) and logistic regression (binary variables). Results: The 432 patients included in the analysis had a median age of 72 and 50% were women (mean NIHSS=6). wbBBB was highly correlated with age (p<0.001); figure 1A shows the 95% confidence intervals for the linear fit between age and wbBBB. There was no significant association with sex (p=0.143), NIHSS (p=0.097), or time from onset (p=0.149). wbBBB was associated with Fazekas score of the deep white matter (p<0.001) and the periventricular white matter (p<0.001). In multivariable analysis, age (p=0.011) and deep WMH (p=0.027), but not periventricular WMH (p=0.725), were independently associated with wbBBB. Figure 1B shows a boxplot of how wbBBB increases with increasing Fazekas score in the deep white matter. Conclusions: Global BBB disruption measured in stroke patients increased with increasing age and cerebral small vessel disease. It remains to be determined if these findings represent an acute exacerbation of a chronic process.