Language assessment in persons with aphasia early after thrombolysis: the utility of multilevel procedures of discourse analysis

Abstract

ABSTRACT Background Clinical guidelines recommend the administration of intravenous recombinant tissue plasminogen activator thrombolytic treatment to persons who suffered ischemic stroke within 4,5 hours since onset. However, the available evidence on the potential improvement of language after thrombolysis is still scanty. Aims This study assessed the effect of thrombolytic treatment in language recovery in persons with stroke aphasia (PWA) comparing the efficacy of traditional language assessments and a multilevel procedure of discourse analysis applied to the Cookie Theft picture descriptions taken from the National Institute of Health Stroke Scale (NIHSS). Methods and procedures Fortyeight individuals participated in the study: sixteen PWA who received thrombolysis; sixteen PWA who did not receive it; sixteen healthy controls. The two groups of PWA were balanced in terms of age, education, gender, lateralization of the lesion, and stroke severity. They were administered the NIHSS and a bedside language assessment battery when entering the neurological clinic (T0) and after approximately 72 hours (T1). Their narrative discourse descriptions were analyzed with a multilevel procedure for discourse analysis. Outcomes and results The two groups of PWA had similar linguistic difficulties at T0 as reflected by comparable Composite Verbal Scores and performance on traditional linguistic bedside assessment (Aphasia PostStroke Acute Assessment test; Furlanis et al., 2018). Discourse analysis highlighted the presence of more omissions of function words and errors of cohesion in the PWA who would receive thrombolysis with respect to healthy controls and allowed for the identification, in both groups, of difficulties that could not be detected through a traditional assessment. At T1 the analyses showed the presence of improvements likely reflecting a generalized spontaneous recovery in both groups of PWA and a more specific recovery triggered by thrombolysis concerning the production of global coherence errors in treated patients only. An inspection of the gravity of the linguistic symptoms at the individual level revealed high interindividual variability in this early phase suggesting that thrombolysis reduced the severity of the impairment also in the production of informative words. Conclusions Thrombolysis reduces the gravity of some linguistic symptoms within a few hours after treatment. Multilevel procedures of discourse analysis can identify these subtle improvements.