Serum leptin levels in children and adolescents with spinal muscular atrophy types 2 and 3

Aim: It has been reported that in patients with spinal muscular atrophy (SMA), lower levels of motor function are associated with hyperleptinemia. Additionally, hyperleptinemia has been found to be more frequent in underweight SMA patients. Therefore, we aimed to analyze serum leptin levels in patients with SMA. Method: This was a cross-sectional study of pediatric patients (2-19 years old) with SMA types 2 and 3. The investigations included anthropometric measurements, assessment of pubertal status, motor function evaluation using the Hammersmith Functional Motor Scale - Expanded (HFMSE), and serum leptin levels. Results: In total, 37 patients (22 with type 2 and 15 with type 3 SMA) were included in the study. The maleto-female ratio was 1:1.3 and 62.2% of patients were prepubertal. No statistically significant correlation was found between the HFMSE score and leptin levels, rs(35) = 0.24, p = 0.15. There was, however, a strong positive relationship between the body mass index (BMI) z-score and leptin levels, rs(35) = 0.87, p < 0.001. Conclusion: Serum leptin levels do not seem to be a useful marker of disease severity in children and adolescents with types 2 and 3 SMA. As in the general pediatric population, leptin levels are strongly correlated with BMI, which is a surrogate measure of body fat.