Real-world respiratory and bulbar comorbidities of SMA type 1 children treated with nusinersen: 2-Year single centre Australian experience.

AIM: To describe the respiratory and nutritional supportive care and hospitalisations required in the real-world scenario in children with SMA type 1 treated with nusinersen. METHODS: Single-centre observational cohort study of children with SMA1 commencing nusinersen from November 2016 to September 2018. Motor, respiratory and nutritional clinical characteristics and management are described from initiation of nusinersen for a minimum of two years. RESULTS: Nine children (5 females, 4 males), median age 10.7 months (range 2.7-181.2) commenced treatment with nusinersen and outcomes were assessed over a total of 270.5 patient months and 209 hospital admissions. Supportive care in newly-diagnosed patients (n = 7) included gastrostomy insertion (n = 4) and commencement of noninvasive ventilation (n = 4) at an average of 8.3 and 4.5 months after diagnosis, respectively. The annualised hospitalisation rate was 9.3/patient/year, average length of stay (LOS) of 3.3 days (SD = 5.6). Children with two SMN2 copies required more gastrostomies (p < 0.05) and had more frequent admissions (p < 0.05). Number of total admissions halved from the first to the second year of treatment in all patients (p < 0.005). INTERPRETATION: Children with treated SMA1 experienced considerable respiratory and bulbar comorbidities, necessitating substantial respiratory and nutritional supportive care. Proactive respiratory and nutritional surveillance and management is essential in SMA1 patients treated with nusinersen.