Universität zu Köln

Lillig, Robert (2024). Development of a new CERAD Total Score in Individuals with Parkinson’s Disease: Evidence from the LANDSCAPE Study. PhD thesis, Universität zu Köln.

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Abstract

Introduction. The Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) is a renowned cognitive test battery for the assessment of cognitive functioning across various neurological conditions, including Parkinson’s Disease (PD). Its German extension, the CERAD-Plus, with additional subscales assessing executive functions and processing speed might offer additional diagnostic value as these two cognitive domains rank among the most vulnerable in individuals with PD. The most established CERAD total score (TS) proposed by Chandler and colleagues is based on arbitrarily selected raw values of the restricted CERAD test battery. Objective. The aim of the thesis project was the development of a new CERAD-TS in individuals with PD based on all available subtests of the extended CERAD-Plus test battery using age-, gender-, and education-corrected z-scores to ultimately test and compare its diagnostic utility with the established Chandler CERAD TS and common PD-screening tools. Methods. The present thesis project analyzed baseline data of 679 individuals with PD of varying cognitive abilities (67.6% male, n = 277 with normal cognition (PD-N), n = 307 with impaired cognition (PD-MCI), n = 95 with dementia (PD-D)) from the multicenter, prospective DEMPREAK/LANDSCAPE cohort. For the comparisons of four different TS based either on the original CERAD or the CERAD-Plus battery with varying weighting of subtests (e.g., rawscores, z-scores or factor-scores) receiver operating characteristics (ROC-) analyses were conducted. Comparisons of the areas under the curve (AUC) were run to identify the most parsimonious TS amongst the four tested TS. Results. The newly designed CERAD-Plus TS based on equally-weighted z-scores proved to be the most accurate and parsimonious TS when discriminating between individuals with PD of varying cognitive impairment (0.78 < AUC < 0.98). Not only was this TS superior to the Chandler CERAD-TS, but the new CERAD-Plus TS also outperformed cognitive screening instruments, such as the Mini Mental Status Examination (MMSE) or the PD-specific Parkinson Neuropsychometric Dementia Assessment (PANDA). Conclusion. Results of this thesis project highlight the importance of non-amnestic CERADPlus subscales (e.g., executive functions and processing speed) in the assessment of cognitive capacities in PD populations with different cognitive functioning, especially at an early stage of disease. An accurate and early diagnosis of PD is the prerequisite for early disease management and subsequent monitoring of disease progression. The new CERAD-Plus TS needs further validation and could prove to be of diagnostic value in non-PD populations as well.

Item Type:	Thesis (PhD thesis)
Translated title:	Title Language Entwicklung eines neuen CERAD Gesamtscores in einer Parkinson Population: Belege aus der LANDSCAPE Studie German
Creators:	Creators Email ORCID ORCID Put Code Lillig, Robert robert.lillig@gmail.com UNSPECIFIED UNSPECIFIED
URN:	urn:nbn:de:hbz:38-753687
Date:	21 January 2024
Language:	English
Faculty:	Faculty of Medicine
Divisions:	Faculty of Medicine > Medizinische Psychologie > Abteilung für Medizinische Psychologie
Subjects:	Psychology Medical sciences Medicine
Uncontrolled Keywords:	Keywords Language Cognitive Impairment English Kognitive Beeinträchtigung German CERAD English Parkinson's disease English Parkinson German Neuropsychological assessment English Neuropsychologische Testung UNSPECIFIED
Date of oral exam:	1 August 2024
Referee:	Name Academic Title Kalbe, Elke Prof. Dr. rer. nat. Kessler, Josef Prof. Dr. soc. Schnitzler, Alfons Prof. Dr. med.
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/75368