The Impact of Acute Phase Domain-Specific Cognitive Function on Post-stroke Functional Recovery

OBJECTIVE To assess whether the cognitive function in the acute stage evaluated by domain-specific neuropsychological assessments would be an independent predictor of functional outcome after stroke. METHODS Forty patients underwent 4 domain-specific neuropsychological examinations about 3 weeks after the onset of stroke. The tests included the Boston Naming Test (BNT), the construction recall test (CRT), the construction praxis test (CPT), and the verbal fluency test (VFT). The Korean version of Modified Barthel Index (K-MBI) at 3 months and the modified Rankin Scale (mRS) at 6 months were investigated as functional outcome after stroke. Functional improvement was assessed using the change in K-MBI during the first 3 months and subjects were dichotomized into 'good status' and 'poor status' according to mRS at 6 months. The domain-specific cognitive function along with other possible predictors for functional outcome was examined using regression analysis. RESULTS The z-score of CPT (p=0.044) and CRT (p<0.001) were independent predictors for functional improvement measured by the change in K-MBI during the first 3 months after stroke. The z-score of CPT (p=0.049) and CRT (p=0.048) were also independent predictors of functional status at post-stroke 6 months assessed by mRS. CONCLUSION Impairment in visuospatial construction and memory within one month after stroke can be an independent prognostic factor of functional outcome. Domain-specific neuropsychological assessments could be considered in patients with stroke in the acute phase to predict long-term functional outcome.