Objective: The present study aimed to determine the utility of supportive motor and nonmotor features in differentiating multiple system atrophy (MSA) with predomainat cerebellar ataxia (MSA-C) from other disorders presenting with cerebellar ataxia.
Background: The latest diagnostic criteria for MSA require the presence of motor and/or nonmotor supportive features for clinical diagnosis. The utility of supportive features has been primarily evaluated in differentiating MSA with predominant parkinsonism (MSA-P) from Parkinson’s disease and other atypical parkinsonian disorders. However, their diagnostic value in distinguishing MSA-C from other disorders presenting with cerebellar ataxia has not been sufficiently investigated.
Method: This single-center, prospective observational study included patients aged ≥18 years with predominantly progressive cerebellar symptoms. Analyses included the systematic evaluation of the Scale for the Assessment and Rating of Ataxia (SARA) score, postvoid residual volume, orthostatic hypotension, and supportive motor and nonmotor features.
Results: Of the 50 enrolled patients, 17 met the diagnostic criteria for MSA-C, which was clinically established and clinically probable in 14 and 3 patients, respectively. The median disease duration was significantly shorter in patients with MSA-C than in those without MSA-C (1.3 years vs. 4.7 years, p < 0.001); however, the SARA scores was comparable between the two groups. Among the supportive motor features, “rapid progression within 3 years of motor onset,” “moderate to severe postural instability within 3 years of motor onset,” and “jerky myoclonic postural or kinetic tremor” were significantly more frequent in patients with MSA-C than in those without MSA-C (p < 0.001 for all). Among the supportive nonmotor features, “inspiratory sighs” were significantly more frequent in patients with MSA-C than in those without MSA-C (p = 0.010). Among the supportive features evaluated, “rapid progression within 3 years of motor onset” demonstrated the highest diagnostic accuracy (84.0%) for distinguishing the patients with MSA-C from those without MSA-C, with a sensitivity of 58.8% and a specificity of 97.0%.
Conclusion: Some of the supportive features included in the latest diagnostic criteria for MSA were useful in differentiating MSA-C from other disorders presenting with cerebellar ataxia.
To cite this abstract in AMA style:
A. Sugiyama, Y. Nakagawa, M. Namiki, S. Hirano, Y. Nakano, T. Yamamoto, Y. Yamanaka, M. Mori. A prospective single-center study investigating the utility of supportive features in the diagnosis of multiple system atrophy with predominant cerebellar ataxia [abstract]. Mov Disord. 2026; 41 (suppl 1). https://www.mdsabstracts.org/abstract/a-prospective-single-center-study-investigating-the-utility-of-supportive-features-in-the-diagnosis-of-multiple-system-atrophy-with-predominant-cerebellar-ataxia/. Accessed October 1, 2026.« Back to 2026 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/a-prospective-single-center-study-investigating-the-utility-of-supportive-features-in-the-diagnosis-of-multiple-system-atrophy-with-predominant-cerebellar-ataxia/