Acute post-stroke cognitive test performance predicts one-year functional independence

Structured AbstractO_ST_ABSObjectiveC_ST_ABSGeneral cognitive ability (g), a latent variable derived from cognitive data, can predict life outcomes (e.g., educational attainment and occupational success) among neurologically healthy individuals. The value of g for predicting post-stroke functional outcomes is unknown. We addressed this gap here. MethodWe derived g using exploratory structural equation modeling of 15 neuropsychological tests administered to 112 patients with stroke, 69 of whom also had functional outcome data (42 men; mean age = 53.23 years (SD = 10.54)). We used logistic regressions to compare g and individual tests in terms of their ability to predict the Functional Assessment Measure (FAM) and the Functional Independence Measure (FIM; motor and cognitive subscales) at 12 months post-stroke. Resultsg was a statistically significant predictor of FAM (X2 = 6.86, p = 0.013) and the cognitive (X2 = 11.48, p = 0.002) but not motor FIM subscale (X2 = 0.93, p = 0.154). Individual tests varied widely in terms of predictive utility (X2 range: 0.07-21.03), with the most robust predictors being measures of visuospatial functions. ConclusionsAcute measures of cognition, including g, can predict functional independence 12 months after stroke. g and visuospatial ability measures were the most robust predictors. Statement of Research SignificanceO_ST_ABSResearch QuestionC_ST_ABSGeneral cognitive ability (or, g) is composite score based on scores on performance-based tests of cognition. In neurologically healthy people, g can predict long-term life outcomes. The value of g measured acutely after stroke for predicting functional outcomes one year later is unknown. We evaluated the utility of g for predicting post-stroke functional outcomes. Main FindingsA g factor based on neuropsychological test data collected from acute stroke patients was a statistically significant predictor of cognitive and psychosocial functional outcomes one year later. Lower g after stroke was linked to higher chance of needing functional assistance. Study ContributionsWhen neuropsychological test data are collected in the acute post-stroke period, it may be possible to derive a g factor score based on those data. Our findings suggest that this g factor score could help clinicians tailor treatment strategies to a patients expected long-term functional outcomes.