Coordination and timing deficits in speech and swallowing in autosomal recessive spastic ataxia of Charlevoix–Saguenay (ARSACS)

Abstract

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a rare early onset neurodegenerative disease that typically results in ataxia, upper motor neuron dysfunction and sensorimotor peripheral neuropathy. Dysarthria and dysphagia are anecdotally described as key features of ARSACS but the nature, severity and impact of these deficits in ARSACS are not known. A comprehensive quantitative and qualitative characterization of speech and swallowing function will support diagnostics, provide insights into the underlying pathology, and guide day-to-day clinical management. 11 consecutive non-Quebec ARSACS patients were recruited, and compared to healthy participants from several published and unpublished cohorts. A comprehensive behavioural assessment including objective acoustic analysis and expert perceptual ratings of motor speech, the Clinical Assessment of Dysphagia in Neurodegeneration (CADN), videofluoroscopy and standardized tests of dysarthria and swallowing related quality of life was conducted. Speech in this ARSACS cohort is characterized by pitch breaks, prosodic deficits including reduced rate and prolonged intervals, and articulatory deficits. The swallowing profile was characterized by delayed initiation of the swallowing reflex and late epiglottic closure. Four out of ten patients were observed aspirating thin liquids on videofluoroscopy. Patients report that they regularly cough or choke on thin liquids and solids during mealtimes. Swallowing and speech-related quality of life was worse than healthy controls on all domains except sleep. The dysphagia and dysarthria profile of this ARSACS cohort reflects impaired coordination and timing. Dysphagia contributes to a significant impairment in functional quality of life in ARSACS, and appears to manifest distinctly from other ARSACS dysfunctions such as ataxia or spasticity.