Aim: One of the parameters that is measurable using bioelectrical impedance is the phase angle (PhA), which is an indicator of skeletal muscle quality. The PhA reflects cellular health and nutritional status and is an important parameter for monitoring recovery after stroke. However, the factors affecting skeletal muscle quality remain unclear. Therefore, this study aimed to identify the factors associated with skeletal muscle quality in patients with acute stroke.
Methods: A total of 505 consecutively hospitalized patients with acute stroke were included in this study. The primary outcome was the PhA measured by bioelectrical impedance analysis, which evaluates muscle quality. Multiple regression analysis was performed to identify the factors affecting PhA.
Results: The mean age of the participants was 75.1 years, and 44% were female. The median National Institutes of Health Stroke Scale (NIHSS) score upon admission was 4, and the mean length of stay was 18 days. The mean PhA for skeletal muscle quality was 4.9° in males and 3.9° in females. Multiple regression analysis showed that age, sex, pre-stroke modified Rankin Scale (pre-mRS), Geriatric Nutritional Risk Index, type 2 diabetes mellitus, atrial fibrillation, and chronic kidney disease had independent effects on PhA (R2 = 0.575; P = 0.001). Age, pre-mRS, NIHSS, dementia, and PhA independently associated with functional independence measure at discharge (R2 = 0.657; P = 0.001).
Conclusions: This study identified determinants contributing to the deterioration of muscle quality upon admission in acute stroke patients. Further investigation is needed to ascertain whether modulation of these factors improves muscle quality. Geriatr Gerontol Int 2025; ••: ••-••.
Keywords: comorbidities; nutrition; phase angle; skeletal muscle quality; stroke.
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