Body composition and muscle strength of patients with amyotrophic lateral sclerosis

Introduction Amyotrophic lateral sclerosis (ALS) is a debilitating condition that affects motor neurons, resulting in muscle weakness, atrophy, and eventual paralysis. Understanding the relationship between muscle strength and body composition is crucial for developing effective therapeutic strategies. Methods This prospective clinical study evaluated the body compositions of patients with ALS and healthy subjects. Patients with ALS were divided into early- and late-phase groups. Body composition was assessed using the InBody S10 bioelectrical impedance scale, whereas muscle mass, fat mass, and muscle quality were assessed using the phase angle. The clinical symptoms were evaluated using the Medical Research Council (MRC) and ALS Functional Rating Scale-Revised (ALSFRS-R) questionnaires. Results Twenty-five sporadic patients with ALS (mean age: 70.1 years; mean disease duration: 22.4 months) and 15 healthy individuals were enrolled. Muscle and fat masses were significantly different between patients with ALS and healthy subjects. Differences in muscle mass and phase angles were observed between patients with early- and late-stage ALS. Differences were observed in extracellular water/total body water and fat mass between patients with ALS and healthy individuals; however, no significant differences were observed between the early and late stages. Strong correlations were observed between muscle mass, age, and disease duration, as well as body composition, MRC, and ALSFRS-R. Discussion This study clarified the differences in body composition between patients with ALS and healthy individuals and between early- and late-stage ALS. Research on body composition matched with BMI may be useful for future treatment and care.