Abstract WP198: Assessment of Changes in Muscle Mass, Strength, and Quality and Activities of Daily Living Among Stroke Patients

Abstract

Introduction: After stroke, paralysis reduces muscle strength on the affected side. The lost muscle strength can be partially restored through stroke rehabilitation. However, even if muscle strength is restored, it is not clear whether muscle mass and quality improve. In recent years, it has become possible to measure muscle mass noninvasively using bioelectrical impedance analysis. Additionally, it is known that the phase angle measured by bioelectrical impedance analysis reflects muscle quality. We measured changes in muscle strength, mass, and quality using a hand dynamometer and bioelectrical impedance analysis in patients undergoing rehabilitation after stroke and examined their relationships with activities of daily living (ADLs) improvement. Hypothesis: Post-stroke rehabilitation improves muscle strength, mass, and quality, as well as ADLs. Methods: This retrospective study was performed at two stroke rehabilitation units from January 2017 to March 2019. Muscle mass and quality were assessed using bioelectrical impedance analysis. ADLs were assessed using the functional independence measure (FIM). We measured the grip strength of the non-affected and affected sides as muscle strength. Each measurement was performed at admission and 4 weeks later. We assessed changes in motor FIM items and examined relationships among data. Results and Conclusions: This study included 179 patients (mean age, 75.5±13.0 years; male/female, 89/90; mean duration after stroke, 27.6±8.7 days). Patients received stroke rehabilitation (159.8±21.6 min/day) 7 days a week individually. Muscle strength and quality significantly increased after 4 weeks on both the non-affected and affected sides. Muscle mass decreased, but there was no significant difference. The results were similar when analyzed by sex. Changes in muscle strength and quality were significantly correlated with ADLs improvement (r=0.56 and 0.43, respectively), but muscle mass was not correlated with ADLs improvement. Thus, post-stroke rehabilitation improves muscle strength and quality, as well as ADLs. Muscle mass is not appropriate to measure the effects of stroke rehabilitation, and it is desirable to instead use muscle strength and quality to assess stroke rehabilitation.