Domain-specific trends in cognitive impairment after acute ischaemic stroke.

Little is known about the pattern of subacutecognitive domain impairments after ischaemic stroke, northe temporal evolution of such impairments. Our objectivewas to investigate the pattern of cognitive impairment indifferent neuropsychological domains up to a year afterischaemic stroke. We included prospectively collected datafrom an observational database of stroke patients at theNational Hospital for Neurology and Neurosurgery, QueenSquare, London, UK. Patients were categorised into temporalgroups according to the time between the indexstroke and neuropsychological profiling. The prevalence ofimpairment in different cognitive domains was then comparedbetween these categories. The final cohort consistedof 209 patients. Frontal executive function, perceptual andnominal skills all showed a strong trend, with levels ofimpairment of approximately 30 % at\1 month and lessthan half this at[3 months (p\0.05). Speed and attentionwas the most impaired domain, but had the greatest trendfor decreasing impairment, from 72.4 % acutely to 37.9 %after 3 months (p\0.01). By contrast, we found thatimpairment in visual and verbal memory showed no statisticallysignificant change over time. Our results suggest adomain-specific improvement in cognition after ischaemicstroke. Early assessments may overestimate longer termcognitive deficits, particularly in speed and attention andperceptual functions. The domain-specific improvementpatterns may help to inform long-term rehabilitation plans,which should not be based solely on cognitive assessmentsundertaken within the first month after stroke.