Brain health imaging markers, post-stroke aphasia and Cognition: A scoping review

• Type of Material: Article
• Authors: Jade Hannan, University of South Carolina; Janina Wilmskoetter, Medical University of South Carolina; Jullius Fridriksson, University of South Carolina; Argye E. Hillis, Johns Hopkins School of Medicine; Leonardo Bonilha, Emory University; Natalie Busby, University of South Carolina
• Language: English
• Date: 2023-01-01
• Publisher: Elsevier
• Publication Version: Final Published Version
• Copyright Statement: © 2023 The Authors
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.nicl.2023.103480
• Title of Journal or Parent Work: NeuroImage: Clinical
• Volume: 39
• Start Page: 103480
• End Page: 103480
• Grant/Funding Information: This work was supported by a grant from the National Institute on Deafness and Other Communication Disorders (P50 DC014664) awarded to author JF and a Science Undergraduate Research Fellowship grant from the South Carolina Honors College awarded to author JH.
• Keywords: Cognition; Aphasia; Humans; Brain health; Magnetic Resonance Imaging; White matter hyperintensities; Cerebral Small Vessel Diseases; Stroke; Brain
• Research Categories: Health Sciences, Radiology; Psychology, Cognitive; Biology, Neuroscience

Abstract

For the past decade, brain health has been an emerging line of scientific inquiry assessing the impact of age-related neurostructural changes on cognitive decline and recovery from brain injury. Typically, compromised brain health is attributed to the presence of small vessel disease (SVD) and brain tissue atrophy, which are represented by various neuroimaging features. However, to date, the relationship between brain health markers and chronic aphasia severity remains unclear. Thus, the goal of this scoping review was to assess the current body of evidence regarding the relationship between SVD-related brain health biomarkers and post-stroke aphasia and cognition. In all, 187 articles were identified from 3 databases, of which 16 articles met the criteria for inclusion. Among these studies, 11 focused on cognition rather than aphasia, while 2 investigated both. Of the 10 studies that used white matter hyperintensities (WMHs) as an indicator of SVD severity, 8 studies (80%) demonstrated a relationship between WMH load and worse cognition in stroke patients. Interestingly, among the studies that specifically investigated aphasia, all 5 studies (100%) demonstrated a relationship between SVD and worse language performance. They also indicated that factors other than brain health (e.g., lesion, age, time post onset) played an important role in determining aphasia severity at a single timepoint. These findings suggest that brain health is likely a crucial factor in the context of aphasia recovery, possibly indicating the necessity of cognitive reserve thresholds for the multimodal cognitive demands associated with language recovery. While SVD and structural brain health are not commonly considered as predictors of aphasia severity, more comprehensive models incorporating brain health have the potential to improve prognosis of post-stroke cognitive and language deficits. Given the variability in the existing literature, a uniform grading system for overall SVD would be beneficial for future research on the mechanisms related to brain networks and neuroplasticity, and their translational impact.