Associations between Upper Extremity Motor Function and Aphasia after Stroke: A Multicenter Cross-Sectional Study

Abstract

Background and Purpose. Poststroke aphasia (PSA) often coexists with upper extremity (UE) motor dysfunction. However, whether the presence of PSA affects UE motor performance, and if language function associates with UE motor performance, are unclear. This study is aimed at (1) comparing the motor status of UE between patients with PSA and without PSA and (2) investigating the association between language function and UE motor status in patients with PSA. Methods. Patients with stroke were compared and correlated from overall and three periods (1-3 months, 4-6 months, and >6 months). Fugl-Meyer assessment for the upper extremity (FMA-UE) and action research and arm test (ARAT) were used to compare the UE motor status between patients with PSA and without PSA through a cross-sectional study among 435 patients. Then, the correlations between the evaluation scale scores of UE motor status and language function of patients with PSA were analyzed in various dimensions, and the language subfunction most closely related to UE motor function was analyzed by multiple linear regression analysis. Results. We found that the scores of FMA-UE and ARAT in patients with PSA were 14 points ((CI) 10 to 18, $p<0.001$ ) and 11 points lower ((CI) 8 to 13, $p<0.001$ ), respectively, than those without PSA. Their FMA-UE ( $r=0.70$ , $p<0.001$ ) and ARAT ( $r=0.62$ , $p<0.001$ ) scores were positively correlated with language function. Regression analysis demonstrated that spontaneous speech ability may account for UE motor function ( $R^2=0.51$ , $p<0.001$ ; $R^2=0.42$ , $p<0.001$ ). Consistent results were also obtained from the analyses within the three time subgroups. Conclusion. Stroke patients with PSA have worse UE motor performance. UE motor status and language function showed positive correlations, in which spontaneous speech ability significantly accounts for the associations.