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Published on: November 21, 2013
Extrapyramidal signs in the primary progressive aphasias
Sarah A Kremen1, Mario F Mendez, Po-Heng Tsai
1VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA. skremen@ucla.edu
American Journal of Alzheimer'S Disease and Other Dementias
|February 2, 2011
Summary
Extrapyramidal signs (EPS) like bradykinesia and rigidity are more common in progressive nonfluent aphasia (PNFA) and progressive logopenic aphasia (PLA) than semantic dementia (SD). These signs may help differentiate primary progressive aphasia (PPA) subtypes.
Area of Science:
- Neurology
- Neuroscience
- Clinical Medicine
Background:
- Extrapyramidal signs (EPS) present differently across primary progressive aphasia (PPA) subtypes: progressive nonfluent aphasia (PNFA), semantic dementia (SD), and progressive logopenic aphasia (PLA).
- Understanding these variations is crucial for accurate diagnosis and patient management.
Purpose of the Study:
- To determine the prevalence of specific categories of EPS in a clinical PPA cohort.
- To assess the utility of EPS in differentiating PPA subtypes.
Main Methods:
- Retrospective review of initial neurological examinations from 103 patients with PPA (49 PNFA, 26 SD, 28 PLA).
- Categorization and prevalence calculation of specific EPS within each PPA subtype.
Main Results:
- EPS were more frequent in PNFA (38.8%) and PLA (35.7%) compared to SD (3.8%).
- Bradykinesia and rigidity were significantly more prevalent in PNFA (22.4% and 30.6%, respectively) than in SD or PLA.
- Positive likelihood ratios indicated bradykinesia and rigidity strongly associated with PNFA.
Conclusions:
- Initial presentation of specific EPS can aid in distinguishing PPA subtypes, especially when linguistic or neuroimaging data are inconclusive.
- EPS may serve as a clinical marker for underlying tauopathy in PPA, bridging clinical symptoms and neuropathology.
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