Objective: To apply an algorithmic approach to interpretation of cognitive data to assess cognitive impairment in RBD participants.
Background: Cognitive changes in emerging neurodegenerative disease can be difficult to detect and quantify, potentially leading to misdiagnosis and/or delayed treatment. Determining the pattern and degree of cognitive change over time in individuals with REM sleep behavior disorder (RBD) may help predict phenoconversion to an overt synucleinopathy. A systematic approach can reduce the variability and uncertainty in clinical diagnosis and decision-making.
Method: As part of the North American Prodromal Synucleinopathy (NAPS) Consortium protocol, 287 participants with RBD completed comprehensive baseline neuropsychological testing utilizing the National Alzheimer Coordinating Center Uniform Data Set version 3 (UDS3). An operationalized impairment rating algorithm was applied to z-scores adjusted for age, education, and sex. Impairment ratings were determined within tasks and within domains to derive a global cognitive impairment rating, where 0=none, 0.5=subtle/questionable, 1=mild, 2=moderate, and 3=severe.
Results: Participants were 81% male, ranging in age from 28-85 (M=64.8, SD=9.81) and education from 6-22 years (M=16.3, SD=2.69). Fifty-seven participants (20%) were impairment-free across all tests administered. Subtle/questionable global impairment was observed in 193 (67%) participants. Twenty-nine (10%) demonstrated mild global impairment, and 7 (<1%) demonstrated moderate global impairment. Subtle impairments were most common in the memory domain (106; 37%), followed by attention/executive (98; 34%). Mild to moderate impairments in attention/executive functioning (25; 9%), language (23; 8%), and memory (19; 7%) were less common. Mild to severe impairments in visuospatial functioning were present in 22 (8%).
Conclusion: An algorithmic approach to assessing cognitive impairment in RBD participants revealed some level of impairment in 80% of participants and subtle impairment in 67%. Future longitudinal assessments will be required to determine the predictive utility of neuropsychological performance for phenoconversion of RBD to an overt synucleinopathy.
This abstract has been presented at the International Lewy Body Dementia Conference in Newcastle, UK, June 16, 2022. It has not been published.
To cite this abstract in AMA style:
G. Schneider, A. Avidan, D. Bliwise, S. Criswell, E. During, J. Elliott, L. Forsberg, J-F. Gagnon, M. Howell, D. Huddleston, A. Keil, J. Lee-Iannotti, M. Lim, J. Mcleland, M. Miglis, E. Mignot, R. Postuma, C. Schenck, D. Shprecher, E. ST. Louis, A. Videnovic, B. Boeve, Y-E. Ju, J. Fields. An Algorithmic Approach to Assessing Cognitive Functioning in Individuals with REM Sleep Behavior Disorder [abstract]. Mov Disord. 2023; 38 (suppl 1). https://www.mdsabstracts.org/abstract/an-algorithmic-approach-to-assessing-cognitive-functioning-in-individuals-with-rem-sleep-behavior-disorder/. Accessed June 15, 2025.« Back to 2023 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/an-algorithmic-approach-to-assessing-cognitive-functioning-in-individuals-with-rem-sleep-behavior-disorder/