Objective: to analyse the anterior-posterior scalp distribution of dominant frequencies with an intra-subject evaluation in a dementia with Lewy bodies patient group.

Background: EEG slowing with pre-alpha dominant frequency in posterior derivations is a supportive biomarker for Dementia with Lewy Bodies diagnosis, with high predictive value for the differential diagnosis with Alzheimer’s Disease.  The appearance of a pre-alpha rhythm is considered to be linked to a dysfunctional thalamo-cortical connection. We hypothesize that the intra-subject evaluation would give information on possible different involvement of anterior and posterior cortical areas in Dementia with Lewy Bodies.

Method: We quantitatively analyzed EEGs of 122 patients from 5 Centers of the European dementia with Lewy bodies Consortium.  EEG spectra values, divided into delta, theta, pre-alpha, alpha frequency bands were described by dominant frequency, dominant frequency variability, frequency prevalence.

Results: Dominant frequency in anterior derivations was lower than in posterior derivations (p=2·10-4).   Dominant frequency variability, frequency prevalence in delta and theta was higher in anterior derivations (3·10-7; 1·10-16; 1·10-5). As a consequence, frequency prevalence in pre-alpha and alpha was lower in anterior than posterior derivations (4·10-3; 1·10-7), due to the prevalence of delta/theta in anterior derivations. In 11% of patients, pre-alpha was dominant in anterior leads while alpha rhythm was still dominant in posterior derivations.

Conclusion: EEG slowing was more severe in anterior derivations. A future longitudinal study should address the possibility that the anterior EEG abnormalities appear earlier in the disease course.

« Back to 2019 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/anterior-eeg-slowing-in-dementia-with-lewy-bodies-a-multicenter-european-cohort-study/