Muscle Weakness is More Strongly Associated with Functional Outcomes in Patients with Stroke Than Sarcopenia or Muscle Wasting: an Observational Study

Background Stroke-related sarcopenia is an important prognosis factor and an intervention target for improving outcomes in patients with stroke. Aim This study aimed to identify the association between sarcopenia, possible sarcopenia, muscle weakness, muscle mass and calf circumference, and the functional outcomes 3 months after stroke. Methods In this single-centre prospective observational study, muscle strength, muscle mass, and calf circumference were measured in patients with acute stroke at hospital discharge. Diagnosis of sarcopenia, possible sarcopenia, muscle weakness, low muscle mass, and low calf circumference were defined according to the 2019 Asian Working Group for Sarcopenia criteria. The primary outcome measure was the modified Rankin Scale (mRS) score at 3 months, with an mRS score of 3 or higher indicating a poor outcome. Logistic regression analysis was conducted to examine independent associations between each assessment and functional outcomes. Results A total of 247 patients (median age: 73 years) were included in this study. The prevalence of sarcopenia was 28% ( n = 70), and in the adjusted model, sarcopenia (aOR = 2.60, 95% CI 1.07–6.31, p = 0.034), muscle weakness (aOR = 3.40, 95% CI 1.36–8.52, p = 0.009), and low muscle mass (aOR = 2.61, 95% CI 1.04–6.52) were significantly associated with poor functional outcome. Nevertheless, other evaluations did not demonstrate an independent association with the outcome. Conclusion Sarcopenia, muscle weakness, and low muscle mass were found to be independently associated with functional outcomes 3 months after stroke, and muscle weakness exhibited the strongest association with outcomes among them.