Polysomnography findings in children with spinal muscular atrophy after onasemnogene-abeparvovec.

BACKGROUND

Sleep disordered breathing (SDB) is common in patients with neuromuscular diseases, including spinal muscular atrophy (SMA). While polysomnography (PSG) findings have been described in natural history studies of patients with SMA, reports regarding PSG in treated children are limited to nusinersen. We aim to describe the sleep characteristics in a cohort of children treated with Onasemnogene-abeparvovec.

METHODS

We conducted a cross-sectional cohort study of children with SMA followed at the University of Florida Center for neuromuscular and rare diseases and had a diagnostic or split night PSG after SMA treatment.

RESULTS

Eight children were included in the cohort (four female), aged 5-250 days at diagnosis. Five children had two survival motor neuron 2 (SMN2) copies, two had three SMN2 copies and one subject had four SMN2 copies. Median age at the time of treatment was 46.5 days (range 20-257). All children received onasemnogene-abeparvovec (OA) before their PSG; in addition to OA, one received nusinersen and one received risdiplam. Apnea hypopnea index (AHI) ranged from 3.6 to 24.1/h. REM AHI was higher than NREM AHI. Median Children's Hospital of Philadelphia Infant test of neuromuscular disorders (CHOP-Intend) score at the time of PSG was 55 (range 33-64). There was no correlation between age at treatment, CHOP-Intend score and AHI.

CONCLUSION

SDB is common in treated children with SMA, regardless of age at diagnosis, treatment and neuromotor scores. While AHI may not be the only indicator of SDB in this population, indications, timing of PSG in this cohort remain unknown.