Abstract
Duchenne muscular dystrophy (DMD) impairs motor function and health-related quality of life (HRQoL), yet data from low- and middle-income countries are scarce. We assessed upper limb functionality with the Upper Limb Functionality Evaluation Scale (EEFES) and HRQoL with the SF36v2 in Chilean patients with DMD at late ambulatory and nonambulatory stages, comparing them with healthy age-matched controls. This cross-sectional study included 17 patients with genetically or biopsy-confirmed DMD and 12 controls. Median upper limb functionality was 51%; proximal domains were most impaired (0%) while distal domains remained preserved (100%). Compared with controls, patients reported markedly lower physical functioning (15% vs. 100%) and general health (62% vs. 82%), with a reduced physical component summary (40 vs. 58), but higher mental component summary (58 vs. 50). Age correlated negatively with upper limb performance (ρ = - 0.73; p = 0.0013), whereas corticosteroid use correlated positively (ρ = 0.73; p = 0.0163). Physical Function 10 (PF10) and General Health 2 items showed the strongest associations with upper limb performance. In this first Chilean cohort using EEFES and SF36v2, DMD patients demonstrated significant physical but relatively preserved mental health. These findings align with international reports and highlight potential sensitive endpoints for clinical trials in resource-limited settings.