Cognitive impairment in REM-sleep behaviour disorder and individuals at risk of Parkinson's disease

Parkinsonism Relat Disord. 2023 Apr:109:105312. doi: 10.1016/j.parkreldis.2023.105312. Epub 2023 Feb 2.

Abstract

Background: Mild cognitive impairment (MCI) is commonly present at the time of Parkinson's Disease (PD) diagnosis, but its prevalence amongst individuals at increased risk of PD is unclear.

Methods: Cognition was assessed using the Montreal Cognitive Assessment (MoCA) in 208 participants in the PREDICT-PD study, and 25 participants with REM-sleep behaviour disorder (RBD). Prevalence of MCI level I was determined in all participants, and level II MCI in the RBD sub-group.

Results: Total MoCA scores were worse in the higher risk than the lower risk group defined as those below the 15th percentile of risk (p = 0.009), and in the RBD group compared to all healthy participants (p < 0.001). The prevalence of MCI level I was 12.8% in the lower-risk, 21.9% in the higher-risk (within the highest 15th percentile) and 64% in RBD participants; 66% of RBD participants had MCI level II with multi-domain MCI, but particularly attention and memory deficits.

Conclusions: Cognitive impairment is increased in different groups at higher risk of PD, particularly in the subgroup formally diagnosed with RBD.

Keywords: Cognition; Epidemiology; Parkinson's disease; Prodrome; REM-Sleep behaviour disorder; Risk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cognition
  • Cognitive Dysfunction* / epidemiology
  • Cognitive Dysfunction* / etiology
  • Cognitive Dysfunction* / psychology
  • Humans
  • Parkinson Disease* / complications
  • Parkinson Disease* / diagnosis
  • Parkinson Disease* / epidemiology
  • REM Sleep Behavior Disorder* / diagnosis
  • REM Sleep Behavior Disorder* / epidemiology
  • REM Sleep Behavior Disorder* / etiology
  • Sleep