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Profiles of Normal Cognition in Essential Tremor

Published online by Cambridge University Press:  04 October 2019

Tess E. K. Cersonsky Open the ORCID record for Tess E. K. Cersonsky [Opens in a new window] ,
Sarah Kellner ,
Silvia Chapman ,
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, CT 06520, USA
Sarah Kellner
Affiliation:
Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT 06520, USA
Silvia Chapman
Affiliation:
Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
Edward D. Huey
Affiliation:
Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
Elan D. Louis
Affiliation:
Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT 06520, USA Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT 06520, USA Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT 06520, USA
Stephanie Cosentino*
Affiliation:
Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
*
*Correspondence and reprint requests to: Stephanie Cosentino, Columbia University Medical Center, 630 West 168th Street, P&S Mailbox 16, New York, NY 10032, USA. E-mail: [email protected]
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Abstract

Objectives:

Patients with essential tremor exhibit heterogeneous cognitive functioning. Although the majority of patients fall under the broad classification of cognitively “normal,” essential tremor is associated with increased risk for mild cognitive impairment and dementia. It is possible that patterns of cognitive performance within the wide range of normal functioning have predictive utility for mild cognitive impairment or dementia. These cross-sectional analyses sought to determine whether cognitive patterns, or “clusters,” could be identified among individuals with essential tremor diagnosed as cognitively normal. We also determined whether such clusters, if identified, were associated with demographic or clinical characteristics of patients.

Methods:

Elderly subjects with essential tremor (age >55 years) underwent comprehensive neuropsychological testing. Domain means (memory, executive function, attention, visuospatial abilities, and language) from 148 individuals diagnosed as cognitively normal were partitioned using k-means cluster analysis. Individuals in each cluster were compared according to cognitive functioning (domain means and test scores), demographic factors, and clinical variables.

Results:

There were three clusters. Cluster 1 (n = 64) was characterized by comparatively low memory scores (p < .001), Cluster 2 (n = 39) had relatively low attention and visuospatial scores (p < .001), and Cluster 3 (n = 45) exhibited consistently high performance across all domains. Cluster 1 had lower Montreal Cognitive Assessment scores and reported more prescription medication use and lower balance confidence.

Conclusions:

Three patterns of cognitive functioning within the normal range were evident and tracked with certain clinical features. Future work will examine the extent to which such patterns predict conversion to mild cognitive impairment and/or dementia.

Keywords

Cognitive agingCerebellar diseasesMovement disordersAttentionMemoryPostural balance
Type
Regular Research
Information
Journal of the International Neuropsychological Society , Volume 26 , Issue 2 , February 2020 , pp. 197 - 209
Copyright
Copyright © INS. Published by Cambridge University Press, 2019 

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