Natural history of Type 2 and 3 spinal muscular atrophy: 2-year NatHis-SMA study

This study aimed to characterize the natural history of spinal muscular atrophy over 24 months; overall, data from 81 patients aged ≥6 years with Type 2 and 3 disease and varied functional abilities were analyzed. Endpoints of interest included motor function, upper limb strength, continuous movement, MRI muscle assessment, lung function, and survival of motor neuron protein levels. Lung function testing (FVC, PCF) was performed every 6 months using a Vitalograph spirometer, with associated software.