Expressive language and social communication abilities in children with spinal muscular atrophy type 1.

Aim: To investigate parent-reported expressive language and social communication abilities in children with spinal muscular atrophy type 1 (SMA1) treated with disease-modifying therapies.

Method: This was a cross-sectional feasibility study performed at the Dubowitz Neuromuscular Centre, London (UK), and the Centro Clinico Nemo Pediatrico, Rome (Italy), testing the use of the MacArthur-Bates Communicative Development Inventories (MB-CDIs, 8 months+) to explore vocabulary production, and the Social Communication Questionnaire (SCQ, 4 years+) to investigate social communication.

Results: Fifteen participants completed the MB-CDIs (age range 2 years 2 months-6 years 9 months). Thirteen out of the 15 acquired verbal skills, although with scores below normal ranges. Thirty-seven completed the SCQ (age range 4 years 0 months-9 years 0 months). Four out of the 37 scored 11 or more, suggesting the need for further assessment for autism spectrum disorder. Three out of four had completed the MB-CDIs and were among the children able to say the lowest number of words. Other areas of concern included routines/ritualized patterns of behaviour (14 out of 37) and hyperreactivity to sensory input (5 out of 37).

Interpretation: Treated children with SMA1 can acquire verbal skills, although this can be delayed. A percentage of them also present with social communication difficulties, especially when expressive language is more severely affected. Further assessments for language and social communication are, therefore, recommended and large prospective studies warranted to better characterize the spectrum of these abilities in treated children with or at risk of SMA1.