Purpose: The purpose of this study was to examine whether differences in motor speech features are related to presentations of dysphagia in progressive supranuclear palsy (PSP) given the sparsity of data examining this relationship.
Method: Motor speech disorder (MSD) type and severity along with specific swallowing variables were analysed to obtain insights among these relationships in 73 participants with PSP.
Result: Results revealed that most participants (93%) had dysarthria, with 19% having co-occurring apraxia of speech (AOS). Greater MSD severity was related to more severe pharyngeal phase impairments (95% CI [-0.917, -0.146], p = 0.008). While certain motor speech and swallowing scores varied minimally across participants, incremental changes in these functions were more likely to occur when specific MSD features were present. A trend for participants with spastic dysarthria and/or AOS to exhibit more severe dysphagia was observed.
Conclusion: This study points to the need for thorough neurological evaluation, with inclusion of speech-language pathology consultation, in the standard of care for PSP. Comprehensive assessment of both motor speech and swallowing functions can inform differential diagnosis and assist patients/families facing decisions regarding modalities for communication and nutrition in the setting of neurodegenerative disease. Additional research may yield greater insights about relevant assessment and intervention considerations in PSP.
Keywords: Progressive supranuclear palsy; apraxia of speech; dysarthria; dysphagia; motor speech disorders; neurodegenerative disease.