Correlations between Dysphagia Severity Scale Scores and Clinical Indices in Individuals with Multiple System Atrophy

Dysphagia significantly impacts prognosis in individuals with multiple system atrophy (MSA). While video-based assessments are practical, their limited availability highlights the need for a simple tool such as the Dysphagia Severity Scale (DSS) in clinical practice.

To evaluate the utility of the DSS in assessing dysphagia in MSA patients and its correlations with clinical indices.

We examined 43 MSA patients using the DSS and other clinical measures, including the Unified MSA Rating Scale (UMSARS) and cerebrospinal fluid 5-hydroxyindoleacetic acid levels. As a follow-up, 11 of 43 patients underwent a secondary DSS evaluation. Spearman's correlation and linear mixed models were used to analyze cross-sectional and longitudinal relationships.

DSS scores were significantly correlated with UMSARS Parts 1, 2, and 4, as well as disease duration and blood pressure changes. This indicates that the DSS is sensitive to MSA-related motor and autonomic dysfunctions, and that the DSS could provide a more detailed assessment of swallowing function compared with the UMSARS Part 1 swallowing subscore. Additionally, DSS score was correlated with cerebrospinal fluid 5-hydroxyindoleacetic acid levels. Our longitudinal analysis further supported the role of DSS score as a reliable marker of dysphagia progression over time.

The DSS is a sensitive and practical tool for evaluating dysphagia. Thus, combining the DSS and UMSARS could improve dysphagia monitoring in individuals with MSA. Our data support the use of the DSS as a valuable clinical and research tool in MSA management.