Electrophysiological (EEG) Indices of Mild Cognitive Impairment and Dementia in Parkinson’s Disease: A Systematic Review

Activity: Talk or presentation typesOral presentation

Description

Introduction
Cognitive impairment and dementia are prevalent in Parkinson’s disease (PD) and significantly impact patients’ quality of life. Accurate prognostic indicators of cognitive decline in this population are needed. Electroencephalography (EEG), a non-invasive measure of brain activity, is one such measure. The current study aimed to systematically review which EEG indices are associated with mild cognitive impairment (PD-MCI) and dementia in PD (PDD).

Method
A systematic literature search was conducted in Embase, MEDLINE, PsycINFO and Web of Science in November 2022 to identify studies using EEG to assess cognition in PD-MCI and PDD.

Results
Of the 1716 studies retrieved, 30 were eligible for inclusion. Spectral power in delta, theta, alpha, beta and gamma bands was most frequently investigated (n=13), followed by functional connectivity (n=9) and event related potentials (ERPs; n=6). Slowing of spectral power, characterised by global increases in delta and theta bands with a concomitant decrease in alpha and beta bands, was found in PD-MCI and PDD (n=11). Reduced functional connectivity between anterior and posterior regions was also associated with cognitive impairment in PD (n=2), together with decreased functional connectivity in the alpha band (n=9) in PD-MCI and PDD. However, two studies displayed normal functional connectivity of delta sources in PD-MCI and PDD respectively. ERP studies revealed deficits in attention and semantic processing associated with PD-MCI/PDD.

Conclusions
This review demonstrates that slowing of EEG activity, reduced functional connectivity and aberrant ERPs are associated with PD-MCI and PDD. Study limitations include small sample sizes and discrepancies in the criteria used to define PD-MCI, together with the wide variety of EEG tasks, montages and analysis pipelines used between sites. Overall, this study highlights the potential application of EEG to predict and monitor cognition in PD. Further work should be undertaken to determine the sensitivity, specificity and prognostic value of these EEG indices.
Period20 Apr 2022
Event titleBritish Geriatrics Society 2023 Northern Ireland Spring Meeting
Event typeConference
LocationAntrim, United KingdomShow on map
Degree of RecognitionRegional