Low Muscle Mass is Associated with Walking Function in Patients with Acute Ischemic Stroke

BACKGROUND Muscle mass might be a possible predictor for walking function in patients with stroke; however, evidence is limited. OBJECTIVE To investigate whether skeletal muscle mass is associated with walking function at discharge during the acute phase. METHODS In this observational cohort study, we assessed skeletal muscle mass in patients with acute ischemic stroke using the noninvasive and portable multifrequency bio-impedance device. This device can easily be used in bedridden patients. Appendicular skeletal muscle mass was converted to skeletal muscle index (SMI) standardizing by height squared (kg/m2). The primary outcome was walking function assessed by the modified Rankin Scale score at acute phase hospital discharge. Logistic regression analysis was used to determine the association between skeletal muscle mass and walking function. RESULTS Of the 107 patients enrolled, low SMI (SMI: male <7.0 kg/m2, female <5.7 kg/m2) was identified in 29.9% (19.7% in men, 48.6% in women). Logistic regression analysis showed that low SMI [OR: 4.02, 95% confidence interval (CI): 1.38-11.7, p = 0.001] independently associated with walking function at discharge. Further, patients with mild and moderate severity had significant difficulty in walking when they had low SMI (p = 0.039). CONCLUSIONS Low skeletal muscle mass at the onset of ischemic stroke is an independent predictor of walking function at discharge during the acute phase. Our findings highlight the importance of detecting skeletal muscle mass in patients with acute ischemic stroke.