Session Information
Date: Wednesday, June 7, 2017
Session Title: Ataxia
Session Time: 1:15pm-2:45pm
Location: Exhibit Hall C
Objective: To study the prevalence and influence of movement disorder signs in SCAs.
Background: Movement disorders are common features in spinocerebellar ataxias (SCAs) but their associations with ataxia progression are not well understood.
Methods: We studied 336 participants with SCA 1, 2, 3 and 6 from the Clinical Research Consortium for Spinocerebellar Ataxias (CRC-SCA) and assessed their movement disorder signs (dystonia, postural tremor, rest tremor, rigidity, and chorea) at baseline. We repeatedly measured ataxia progression by the Scale for Assessment and Rating of Ataxia (SARA) every 6 months for 2 years. We employed regression models to study the effects of movement disorder signs on ataxia progression after adjusting for age, sex and pathological CAG repeats.
Results: Dystonia is most common in SCA3 (25%), whereas postural tremor, rest tremor, and chorea are most common in SCA2 (29%, 13%, and 14%, respectively). Rigidity is more prevalent in SCA2 and SCA3 (20% and 17%, respectively). SCA1, 2, 6 patients with movement disorder signs and those without movement disorder signs do not differ in their pathological CAG repeat length except that SCA1 patients with rigidity have a shorter CAG repeat length than SCA1 patients without rigidity. SCA3 patients with dystonia or postural tremor have a longer CAG repeat length, whereas SCA3 patients with rest tremor have a shorter CAG repeat length. In SCA1, postural tremor is associated with slower ataxia progression, whereas chorea is associated with faster progression. Postural tremor and rigidity predict faster deterioration in SCA2 and SCA3, respectively. Although movement disorders are relatively rare in SCA6, the presence of movement disorder signs (dystonia, postural tremor, rest tremor, or rigidity) is associated with slower ataxia progression.
Conclusions: Movement disorder signs are common in SCAs and are associated with different rates of clinical progression. Thus, SCAs with distinct movement disorder signs might represent subtypes of diseases preferentially involved with diverse neural circuitry within and outside the cerebellum.
To cite this abstract in AMA style:
P.-H. Kuo, J. Wang, K. Figueroa, S. Pulst, S. Perlman, G. Wilmot, C. Gomez, J. Schmahmann, H. Paulson, V. Shakkottai, S. Ying, T. Zesiewicz, K. Bushara, M. Geschwind, G. Xia, S. Subramony, T. Ashizawa, S.-H. Kuo. Movement Disorders and Clinical Progression in Spinocerebellar Ataxias [abstract]. Mov Disord. 2017; 32 (suppl 2). https://www.mdsabstracts.org/abstract/movement-disorders-and-clinical-progression-in-spinocerebellar-ataxias/. Accessed May 15, 2025.« Back to 2017 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/movement-disorders-and-clinical-progression-in-spinocerebellar-ataxias/