Background and purpose: The optimal management of post-stroke cognitive impairment (PSCI) remains controversial. These joint European Stroke Organisation (ESO) and European Academy of Neurology (EAN) guidelines provide evidence-based recommendations to assist clinicians in decision making regarding prevention, diagnosis, treatment and prognosis. Methods: Guidelines were developed according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The working group © 2021 European Academy of Neurology and European Stroke OrganisationThe article has been published in the European Stroke Journal and European Journal of Neurology. The articles are identical except for minor stylistic and spelling differences in keeping with each journal's style. To request permission to reuse any part of this article, please go to Wiley's HYPERLINK "https://www.wiley.com/en-gb/right s&permi ssion sportal testing. There was insufficient evidence to make a recommendation for use of cholinesterase inhibitors, memantine nootropics or cognitive rehabilitation. There was limited evidence on the use of prediction tools for post-stroke cognition. The association between PSCI and acute structural brain imaging features was unclear, although the presence of substantial white matter hyperintensities of presumed vascular origin on brain magnetic resonance imaging may help predict cognitive outcomes.Conclusions: These guidelines highlight fundamental areas where robust evidence is lacking. Further definitive RCTs are needed, and we suggest priority areas for future research.

Introduction: The optimal management of post stroke cognitive impairment remains controversial. These joint European Stroke Organisation (ESO) and European Academy of Neurology (EAN) guidelines provide evidence-based recommendations to assist clinicians in decision making around prevention, diagnosis, treatment, and prognosis. Methods: These guidelines were developed according to ESO standard operating procedure and the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and, where possible, meta-analyses of the literature, assessed the quality of the available evidence, and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available to provide recommendations based on the GRADE approach. Results: There was limited randomised controlled trial evidence regarding single or multicomponent interventions to prevent post stroke cognitive decline. Interventions to improve lifestyle and treat vascular risk factors may have many health benefits but a beneficial effect on cognition is not proven. We found no evidence around routine cognitive screening following stroke but recognise the importance of targeted cognitive assessment. We described the accuracy of various cognitive screening tests but found no clearly superior approach to testing. There was insufficient evidence to make a recommendation for use of cholinesterase inhibitors, memantine or cognitive rehabilitation for post stroke dementia. We made a weak recommendation against using the nootropics actovegin and cerebrolysin, but quality of evidence was very low. There was limited evidence on the use of prediction tools for post stroke cognitive syndromes (cognitive impairment, dementia and delirium). The association between post stroke cognitive impairment and most acute structural brain imaging features was unclear. Conclusions: These guidelines have highlighted fundamental areas where robust evidence is lacking. Further randomised controlled trials are needed and we suggest priority areas for future research.

Semantic cognition is supported by two interactive components: semantic representations and mechanisms that regulate retrieval (cf. ‘semantic control’). Neuropsychological studies have revealed a clear dissociation between semantic and episodic memory. This study explores if the same dissociation holds for control processes that act on episodic and semantic memory, or whether both types of long-term memory are supported by the same executive mechanisms. We addressed this question in a case-series of semantic aphasic patients who had difficulty retrieving both verbal and non-verbal conceptual information in an appropriate fashion following infarcts to left inferior frontal gyrus (LIFG). We observed parallel deficits in semantic and episodic memory: (i) the patients' difficulties extended beyond verbal materials to include picture tasks in both domains; (ii) both types of retrieval benefitted from cues designed to reduce the need for internal constraint; (iii) there was little impairment of both semantic and episodic tasks when control demands were minimised; (iv) there were similar effects of distractors across tasks. Episodic retrieval was highly susceptible to false memories elicited by semantically-related distractors, and confidence was inappropriately high in these circumstances. Semantic judgements were also prone to contamination from recent events. These findings demonstrate that patients with deregulated semantic cognition have comparable deficits in episodic retrieval. The results are consistent with a role for LIFG in resolving competition within both episodic and semantic memory, and also in biasing cognition towards task-relevant memory stores when episodic and semantic representations do not promote the same response.

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Background: Identifying whether acute stroke patients are at risk of cognitive decline could improve prognostic discussions and management. Structural computed tomography (CT) neuroimaging is routine in acute stroke, and may, identify those at risk of post-stroke dementia (PSD) or post-stroke cognitive impairment (PSCI). Aim: To systematically review the literature to identify which stroke or pre-stroke features on brain CT scans, performed at the time of stroke, are associated with PSD or PSCI. Summary of review: We searched electronic databases to December 2020. We included studies reporting acute stroke brain CT, and later diagnosis of a cognitive syndrome. We created summary estimates of size of unadjusted association between CT features and cognition. Of 9536 citations, twenty-eight studies (41 papers) were eligible (N=7078, mean age 59.8-78.6 years). Cognitive outcomes were PSD (10 studies), PSCI (17 studies), and one study analysed both. Fifteen studies (N=2952) reported data suitable for meta-analyses. White matter lesions (WML) (6 studies, N=1054, OR=2.46, 95% CI=1.25-4.84), cerebral atrophy (4 studies, N=558, OR=2.80, 95% CI=1.21-6.51), and pre-existing stroke lesions (3 studies, N=352, OR=2.38, 95% CI=1.06-5.32) were associated with PSD. WML (4 studies, N=473, OR=3.46, 95% CI=2.17-5.52) were associated with PSCI. Other CT features were either not associated with cognitive outcome, or there were insufficient data. Conclusions: Cognitive impairment following stroke is of great concern to patients and carers. Features seen on visual assessment of acute stroke CT brain scans are strongly associated with cognitive outcomes. Clinicians should consider when and how this information should be discussed with stroke survivors.