Cognitive impairment after a stroke in young adults: a systematic review and meta-analysis.

BackgroundInformation about cognitive functioning is vital in the management of stroke, but the literature is mostly based on data from individuals older than 50 years of age who make up the majority of the stroke population. As cognitive functioning is subject to change due to ageing, it is unclear whether such cognitive impairment patterns from the general stroke literature apply to the growing population of younger people with a stroke.AimsTo conduct a systematic review and meta-analysis of the proportion and severity of cognitive impairment in young-stroke patients.Summary of reviewMEDLINE, Embase, PsycINFO, and Web of Science were systematically searched up to 11 October 2022. Studies were included if they reported on a population of young-stroke patients, evaluated cognitive functioning as an outcome measure, and reported original data. We estimated the pooled prevalence rates for cognitive impairment and for aphasia. Additionally, we calculated the pooled estimates for the severity of impairment per cognitive domain in the chronic phase (defined as >6 months post-stroke). 635 articles were identified of which 29 were eligible for inclusion. The pooled prevalence of cognitive impairment was 44% (k=10; 95% CI: 34-54%) and of aphasia 22% (k=13; 95% CI: 12-39%). Young-stroke patients in the chronic phase performed worse than stroke-free healthy age-appropriate controls across all cognitive domains examined, with Hedge's g effect sizes from -0.49 to -1.64.ConclusionsAround half of all young-stroke patients present with cognitive impairment and around a quarter with aphasia. Our data suggests that patterns of impairment in young-stroke patients follow those in the general stroke literature.