Disease Burden in Children With Spinal Muscular Atrophy: Results From a Large Cross-Sectional Study

Background:To facilitate advances in spinal muscular atrophy therapeutic research, it is important to determine the impact and prevalence of symptoms experienced by children with spinal muscular atrophy. Methods: We conducted qualitative interviews with caregivers of children with spinal muscular atrophy. From these interviews, we generated a survey inquiring about 260 symptoms of importance grouped into 17 symptomatic themes. Results: Sixteen caregivers of children with spinal muscular atrophy aged from 4 months to 12 years participated in initial interviews, and 77 caregivers completed the survey. Higher symptom prevalence was associated with spinal muscular atrophy type, SMN2 copy number, and functional status. Hip, thigh, or knee weakness had the greatest reported impact on the lives of children with spinal muscular atrophy. Conclusions: This research provides one of the largest data sets regarding disease burden in children with spinal muscular atrophy. The most prevalent symptoms are not identical to those with the greatest impact. This unique insight into the most impactful symptoms will help focus therapeutic development in spinal muscular atrophy.