Association between serum copper concentration and body composition in children with spinal muscular atrophy: a cross-sectional study

Background and Objectives: The role of serum copper in modulating body composition in patients with spinal muscular atrophy (SMA) remains uncertain. This study aimed to illustrate the correlation between serum copper concentration and body composition in children with SMA. Methods and Study Design: This study was conducted at a pediatric medical center in China from July 2019 to August 2022. The study included anthropometric measurements, serum analysis for copper, magnesium, zinc, and iron, as well as comprehensive body composition assessments. Multivariate analysis was utilized to assess the connection between serum copper concentration and body composition metrics. Results: This cross-sectional analysis included 87 patients [median (IQR) age: 7 years (5-10), 57.5% male] diagnosed with SMA receiving comprehensive multidisciplinary management. The results revealed a positive association between serum copper concentration and both fat mass percentage ((3 = 0.50, 95% confidence interval (CI): 0.07 to 0.92, p = 0.025) and fat-muscle ratio ((3 = 0.02, 95% CI: 0.01 to 0.03, p = 0.009). Conversely, a negative correlation was found between serum copper concentration and muscle mass percentage ((3 = -0.70, 95% CI: -1.11 to -0.29, p = 0.001). Conclusions: These findings suggest a correlation between copper concentration and body composition in SMA, offering valuable insights for addressing metabolic dysregulation in these patients.