190PSarcopenia severity in dystrophinopathy patients in Puerto Rico

Dystrophinopathies are genetic disorders characterized by muscle degeneration and weakness due to mutations in the dystrophin protein. Sarcopenia is defined as age/disease-related loss of muscle mass, strength, and function, and is a key component in the progression of dystrophinopathies. Quantification of muscle mass and its correlation with functional deterioration is essential for assessing disease progression and evaluating therapeutic interventions. This study aims to quantify body composition in patients with dystrophinopathies and understand the relationship between lean muscle mass, strength, and functional outcomes to assess sarcopenia severity. This cross-sectional study included 31 male patients with dystrophinopathies, aged 4-27. Body composition, including lean tissue mass, was assessed using a whole-body Dual-Energy X-ray Absorptiometry (DEXA) scan. Isometric strength of handgrip, elbow flexors, and knee extensors were measured using dynamometers. Functional assessments, including the North Star Ambulatory Assessment (NSAA), 10-meter walk test (10MWT), revised upper limb module (RULM), and the Brooke/Vignos scale were performed. These variables were correlated with lean tissue mass using regression analysis. Preliminary findings show that lean tissue mass decreases with age. Moderate positive correlation was found between lean tissue mass and isometric strength in elbow flexors and knee extensors. Strong positive correlation was found between lean tissue mass and functional tests, including the NSAA, 10MWT, Brooke, and Vignos scale. Final results will be available at the date of presentation. The positive correlations between lean tissue mass and strength, as well as functional outcomes, highlight the role of muscle mass in disease progression. These results suggest that the evaluation of lean tissue mass may serve as a biomarker for monitoring therapeutic interventions aimed at preserving muscle mass and function.