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Informant-Reported Cognitive Decline is Associated with Objective Cognitive Performance in Parkinson’s Disease

Published online by Cambridge University Press:  09 December 2020

Marina Z. Nakhla Open the ORCID record for Marina Z. Nakhla [Opens in a new window] ,
Kelsey A. Holiday ,
J. Vincent Filoteo ,
Zvinka Z. Zlatar ,
Vanessa L. Malcarne ,
Stephanie Lessig ,
Irene Litvan  and
Dawn M. Schiehser
Marina Z. Nakhla
Affiliation:
Research Service, VA San Diego Healthcare System, La Jolla, California, 3350 La Jolla Village Dr, San Diego, CA92161, USA SDSU/UC San Diego Joint Doctoral Program in Clinical Psychology, 6363 Alvarado Ct, San Diego, CA, USA
Kelsey A. Holiday
Affiliation:
Research Service, VA San Diego Healthcare System, La Jolla, California, 3350 La Jolla Village Dr, San Diego, CA92161, USA SDSU/UC San Diego Joint Doctoral Program in Clinical Psychology, 6363 Alvarado Ct, San Diego, CA, USA
J. Vincent Filoteo
Affiliation:
Research Service, VA San Diego Healthcare System, La Jolla, California, 3350 La Jolla Village Dr, San Diego, CA92161, USA Department of Psychiatry, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA92093, USA Department of Neurosciences, Movement Disorder Center, University of California, San Diego, CA, USA
Zvinka Z. Zlatar
Affiliation:
Department of Psychiatry, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA92093, USA
Vanessa L. Malcarne
Affiliation:
SDSU/UC San Diego Joint Doctoral Program in Clinical Psychology, 6363 Alvarado Ct, San Diego, CA, USA Department of Psychiatry, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA92093, USA Department of Psychology, San Diego State University, 5500 Campanile Dr, San Diego, CA92182, USA
Stephanie Lessig
Affiliation:
Research Service, VA San Diego Healthcare System, La Jolla, California, 3350 La Jolla Village Dr, San Diego, CA92161, USA Department of Neurosciences, Movement Disorder Center, University of California, San Diego, CA, USA
Irene Litvan
Affiliation:
Research Service, VA San Diego Healthcare System, La Jolla, California, 3350 La Jolla Village Dr, San Diego, CA92161, USA Department of Neurosciences, Movement Disorder Center, University of California, San Diego, CA, USA
Dawn M. Schiehser*
Affiliation:
Research Service, VA San Diego Healthcare System, La Jolla, California, 3350 La Jolla Village Dr, San Diego, CA92161, USA Department of Psychiatry, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA92093, USA
*
*Correspondence and reprint requests to: Dawn Schiehser, Ph.D., Research Service, VA San Diego Healthcare System, MC 151-B, La Jolla, CA 92161, USA. Tel.: +1 858 552 8585 ext. 2664; Fax: 858-404-8389. Email: dschiehser@ucsd.edu
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Abstract

Objective:

The utility of informant-based measures of cognitive decline to accurately describe objective cognitive performance in Parkinson’s disease (PD) without dementia is uncertain. Due to the clinical relevance of this information, the purpose of this study was to examine the relationship between informant-based reports of patient cognitive decline via the Informant Questionnaire of Cognitive Decline in the Elderly (IQCODE) and objective cognition in non-demented PD controlling for cognitive status (i.e., mild cognitive impairment; PD-MCI and normal cognition; PD-NC).

Method:

One-hundred and thirty-nine non-demented PD participants (PD-MCI n = 38; PD-NC n = 101) were administered measures of language, executive function, attention, learning, delayed recall, visuospatial function, mood, and motor function. Each participant identified an informant to complete the IQCODE and a mood questionnaire.

Results:

Greater levels of informant-based responses of patient cognitive decline on the IQCODE were significantly associated with worse objective performance on measures of global cognition, attention, learning, delayed recall, and executive function in the overall sample, above and beyond covariates and cognitive status. However, the IQCODE was not significantly associated with language or visuospatial function.

Conclusions:

Results indicate that informant responses, as measured by the IQCODE, may provide adequate information on a wide range of cognitive abilities in non-demented PD, including those with MCI and normal cognition. Findings have important clinical implications for the utility of the IQCODE in the identification of PD patients in need of further evaluation, monitoring, and treatment.

Keywords

Subjective cognitive declineParkinson’s diseaseNeuropsychologySubjective and objective cognitionInformant reportsCognition
Type
Regular Research
Information
Journal of the International Neuropsychological Society , Volume 27 , Issue 5 , May 2021 , pp. 439 - 449
Copyright
Copyright © INS. Published by Cambridge University Press, 2020

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