Abstract TP67: The Contribution of White Matter Pathology to Language Deficits Following Acute Subcortical Left Hemisphere Stroke

Abstract

Background: White matter degeneration, or leukoaraiosis (LA), occurs in aging and increases risk of subcortical stroke. Yet, it remains unclear whether frank lesion and LA are independently predictive of language impairments in patients with left hemisphere (LH) acute subcortical stroke. Methods: Patients with acute LH subcortical stroke (<10 days post-onset) participated (n=75). We manually traced lesions on DWI scans and calculated lesion volume/location with NiiStat. LH and right hemisphere (RH) LA were rated on T2-weighted images using the Fazekas et al. (1987) periventricular (PVH) and deep white matter hyperintensities (DWMH) subscales. We generated language z-scores reflecting auditory comprehension, naming, and repetition skills. We assessed relationships between demographic and stroke factors and LA using t-tests and correlations. We used hierarchical linear regression to determine independent associations between lesion volume and LA and language deficits. Results: For each hemisphere and Fazekas subscale, we found no significant associations between LA severity and lesion volume (r=-.27- -.07, p>.08) or sex (t=.78-1.51, p>.14). Older age was significantly related to more severe LA (r=.40-.49, p<.001). Greater lesion volume was associated with poorer language abilities (t=-2.08, p=.04). When LH and RH PVH ratings were separately added to this model, both multivariate models were significant (F=3.90 p=.03 (LH), F=3.66, p=.03 (RH)), yet neither lesion volume (p=.08 (LH), p=.08 (RH)) nor PVH ratings (p=.06 (LH), p=.10 (RH)) independently predicted language. Models containing lesion volume and DWMH ratings were not significant (p>.11). Discussion: Overall, lesion volume but not LA independently predicts language abilities in patients with acute subcortical LH stroke. Future directions include investigating the individual contributions of frank lesion, LA, and hypoperfusion on aphasia in a larger cohort of patients with acute subcortical stroke.