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Evaluating Mild Cognitive Impairment in Essential Tremor: How Many and Which Neuropsychological Tests?

Published online by Cambridge University Press:  10 October 2018

Tess E.K. Cersonsky ,
Sarah Morgan ,
Sarah Kellner ,
Daphne Robakis ,
Xinhua Liu ,
Edward D. Huey ,
Elan D. Louis  and
Stephanie Cosentino
Tess E.K. Cersonsky
Affiliation:
Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, Connecticut
Sarah Morgan
Affiliation:
Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, Connecticut
Sarah Kellner
Affiliation:
Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, Connecticut
Daphne Robakis
Affiliation:
Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, Connecticut
Xinhua Liu
Affiliation:
Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, New York
Edward D. Huey
Affiliation:
Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, New York Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, New York Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York
Elan D. Louis
Affiliation:
Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, Connecticut Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, Connecticut Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, Connecticut
Stephanie Cosentino*
Affiliation:
Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, New York Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York
*
Correspondence and reprint requests to: Stephanie Cosentino; Columbia University Medical Center, 630 West 168th Street; P&S Mailbox 16; NY, NY 10032; E-mail: [email protected]
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Abstract

Objectives: Essential tremor (ET) confers an increased risk for developing both amnestic and non-amnestic mild cognitive impairment (MCI). Yet, the optimal measures for detecting mild cognitive changes in individuals with this movement disorder have not been established. We sought to identify the cognitive domains and specific motor-free neuropsychological tests that are most sensitive to mild deficits in cognition as defined by a Clinical Dementia Rating (CDR) of 0.5, which is generally associated with a clinical diagnosis of MCI. Methods: A total of 196 ET subjects enrolled in a prospective, longitudinal, clinical-pathological study underwent an extensive motor-free neuropsychological test battery and were assigned a CDR score. Logistic regression analyses were performed to identify the neuropsychological tests which best identified individuals with CDR of 0.5 (mild deficits in cognition) versus 0 (normal cognition). Results: In regression models, we identified five tests in the domains of Memory and Executive Function which best discriminated subjects with CDR of 0.5 versus 0 (86.9% model classification accuracy). These tests were the California Verbal Learning Test II Total Recall, Logical Memory II, Verbal-Paired Associates I, Category Switching Fluency, and Color-Word Inhibition. Conclusions: Mild cognitive difficulty among ET subjects is best predicted by combined performance on five measures of memory and executive function. These results inform the nature of cognitive dysfunction in ET and the creation of a brief cognitive battery to assess patients with ET for cognitively driven dysfunction in life that could indicate the presence of MCI. (JINS, 2018, 24, 1084–1098)

Keywords

Movement disordersCognitionMental status and dementia testsMemory and learning testsMemoryExecutive function
Type
Regular Research
Information
Journal of the International Neuropsychological Society , Volume 24 , Issue 10 , November 2018 , pp. 1084 - 1098
Copyright
Copyright © The International Neuropsychological Society 2018 

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