285th ENMC international workshop: SMN-associated neurodevelopmental disorder: type 1 spinal muscular atrophy and the brain, 31st January - 2nd February 2025, Hoofddorp, The Netherlands.

Recent advances in spinal muscular atrophy (SMA) early diagnosis and treatment have significantly improved survival and motor outcomes, particularly for those with severe phenotypes. However, clinicians have observed unexpected cognitive, social, communication, and behavioural differences in a proportion of children. The 285th ENMC workshop convened 28 experts from 13 countries to address these neurodevelopmental concerns. Key outcomes included confirming the presence of challenges in neurodevelopment in a substantial proportion of treated SMA type 1 children, identifying higher-risk subgroups, and emphasizing the need for early identification, timely referrals, and family support. Participants agreed on a core screening strategy and highlighted the importance of international collaboration to develop specific diagnostic and intervention guidelines. Future steps involve launching an online survey to assess the prevalence of neurodevelopmental disorders and study their characteristics and trajectories, developing care guidelines, and promoting research working groups to further understand brain development in SMA and improve patient care.