Abdominal muscle strength and the recovery of upper extremity function in stroke patients: a study using propensity score matching

Abstract

Purpose The purpose of this study was to understand the relationship between abdominal muscle strength and recovery of upper limb function, after adjusting for various confounding factors, such as age, gender, and sensory function. Methods We retrospectively analyzed data of 78 sub-acute stroke patients with mild-to-moderate upper limb dysfunction. Participants were divided into two groups, strong and weak, according to the abdominal muscle strength. The improvement of scores on the Simple Test for Evaluating Hand Function was compared between the groups. We employed propensity score matching to adjust for numerous relevant variables, including age, affected side, duration from onset, upper limb function, grip strength, sensory function, visuospatial perception, motivation, and cognitive function at admission. Results The improvement of scores on the Simple Test for Evaluating Hand Function of the strong group was significantly larger than the weak one, both before and after matching. This trend was noted in the subgroup analysis of participants with moderate dysfunction on admission; however; the trend was not clearly noticeable in participants with mild dysfunction. Conclusions Our results suggest that abdominal muscle strength is significantly associated with the recovery of upper limb function in sub-acute stroke patients, especially in those with moderate upper limb dysfunction. Implications for Rehabilitation Abdominal muscle strength is associated with the recovery of upper limb function in subacute stroke patients with moderate upper limb dysfunction. Abdominal muscle strength can be used as a predictive factor for the prognosis of upper limb function in stroke patients.