Lung function decline is steeper in children with spinal muscular atrophy (SMA) type 2 between ages 5 and 12, while in SMA type 3 the decline is steepest after age 8.
Why this matters
Respiratory function decline is the most common non-neurologic symptom in SMA and a known cause of mortality. Despite this, most studies have focused on treatments to improve motor function and life expectancy. This is the largest observational study on respiratory functions in pediatric SMA and provides novel information on which to base future treatments and clinical trials on.