A contemporary analysis of the Australian clinical and genetic landscape of spinal muscular atrophy: a registry based study.

BACKGROUND

New paradigms of diagnosis and treatment have changed the neurodegenerative trajectory for individuals with spinal muscular atrophy (SMA). Registries are a critical tool to provide real-world data on treatment patterns, their effects and health care provision within this evolving paradigm of care. This study aimed to evaluate the phenotypic and genotypic landscape, treatment patterns and health impact of SMA in Australia through the national registry.

METHODS

This cross-sectional study investigated demographic, clinical and genetic information, sequelae of weakness, treatment patterns and patient-reported outcomes amongst individuals with SMA enrolled in the Australian Neuromuscular Disease Registry (ANMDR) from 1st January 2020 to 30th April 2023. Descriptive statistics were used for analysis and Chi-Squared or Fisher's exact tests for associations.

FINDINGS: 195 individuals with SMA enrolled into the ANMDR. 5/195 (2.6%) were deceased by censor date. Of (n = 190) individuals living with SMA, 104/190 (54.7%) were children. Minimum Australian prevalence was 0.73/100,000. SMN2 copies were inversely associated with phenotype in those with homozygous SMN1 deletions (p < 0.0001)). Treatment was utilised in 154/190 (81%) of the population, with 65/137 (47.6%) of individuals perceiving improvements with therapeutic intervention on Patient/Parent Global Impression of Improvement scale (p < 0.0001). Engagement with multidisciplinary care practitioners was significantly higher among children with SMA than adults (93% versus 12%, p < 0.0001).

INTERPRETATION: Despite diagnostic and therapeutic advances, mortality and the multi-systemic health impact of SMA continue to be experienced within the Australian population. Healthcare provision must align with patient-centred outcomes, adapting to meeting their changing but ongoing care requirements. The study identified the considerable unmet need for multidisciplinary care, not only for adults with SMA but also for the emerging cohort of treated children, emphasising the imperative for comprehensive healthcare provision to address their evolving needs.

FUNDING: No funding was received for this study.