Aphasiology researchers from Johns Hopkins University and the University of South Carolina have analyzed relationships in research data to advance understandings of deficit and recovery patterns in persons with stroke-induced aphasia during the first 6 months after stroke. Specific goals of this work were to relate observed improvements in confrontation naming and spontaneous speech performance to: [1] the size and location of lesions in subjects’ brains; and [2] to use or non-use of antidepressant medications by patients during that first half-year window.
Data were collected at the two institutions under four distinct aphasia research initiatives. Three of the four projects were at Johns Hopkins University, and one was at the University of South Carolina. Two of these data sets used scores from the Boston Naming Test-short form to probe confrontation naming performance, the others used the Naming subtest of the Western Aphasia Battery-Revised (WAB-R). Spontaneous Speech was assessed in 2 of the 4 initiatives – one by counting Correct Content Units from patient descriptions of the WAB’s Cookie Theft Picture, the other through ‘fluency’ ratings on the WAB’s Spontaneous Speech subtest. Altogether, 251 persons with aphasia were enrolled in the 4 initiatives, and these covered a very wide range both of diagnostic categories of aphasia, and of severity levels within categories. All four initiatives volumetrically reported stroke-induced lesion damage to specific cerebral parcels of interest, with lesion volumes captured at the resolution of 1mm3. In two of the initiatives, the patients were medically administered selective serotonin reuptake inhibitors (SSRI) as antidepressants. Lesion volumes in cerebral areas of interest were correlated with changes in impairment-level assessment data, and also with SSRI usage. Given the heterogeneous study designs, the authors used a mixed-methods approach to data analysis, employing both parametric and non-parametric statistics. They first used data from two longitudinal studies to identify variables of interest, and then tested these variables using data from two independent cohorts, using chi-square tests, multivariate logistic regression, and t-tests.
These data analyses indicate that larger lesions in the posterior superior temporal gyrus and the superior longitudinal fasciulus/arcuate fasciculus in the left cerebral hemisphere are associated with poorer outcomes in naming. The use of SSRIs was associated with greater recovery in naming performance, providing they took the medication for three months following their stroke. In those with no damage to the areas of interest, SSRI use was not associated with outcome improvements.
For further reading: A. E. Hillis, Y. Y. Beh, R. Sebastian et al., 2018, Predicting recovery in acute poststroke aphasia. Annals of Neurology, 83(3): 612–622, https://doi.org/10.1002/ana.25184