J Clin Neurol.  2009 Jun;5(2):81-84. 10.3988/jcn.2009.5.2.81.

Cognitive Impairment in Essential Tremor without Dementia

• Kim JS
• Song IU
• Shim YS
• Park JW
• Yoo JY
• Kim YI
• Lee KS

• KMID: 2287658
• DOI: http://doi.org/10.3988/jcn.2009.5.2.81

Abstract

BACKGROUND AND PURPOSE: Several clinical studies have demonstrated that patients with essential tremor (ET) may have cognitive deficits; however, there are no published data regarding detailed neuropsychological assessments of ET without dementia. We therefore conducted a case-control study of cognitive function in patients with ET.
METHODS
The cohort for this study comprised 34 consecutive patients with ET without dementia and 33 age-matched controls, all of who completed a dementia-screening questionnaire and underwent a detailed neuropsychological investigation.
RESULTS
Severe impairments were observed in most domains for the ET group compared to the controls, including attention, part of language function, verbal memory, and frontal executive functions.
CONCLUSIONS
Our results support the finding that the subclinical cognitive deficits characterized by attention, verbal memory impairments, and executive dysfunction are a clinical feature of ET. In addition, our results also support the finding that age at examination and educational status are the most important risk factors associated with cognitive deficits in patients with ET.

Keyword

essential tremor; cognition; age; education

MeSH Terms

Case-Control Studies
Cognition
Cohort Studies
Dementia
Educational Status
Essential Tremor
Executive Function
Humans
Memory
Risk Factors
Surveys and Questionnaires

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