Electroencephalography Is a Good Complement to Currently Established Dementia Biomarkers

Abstract

Background/Aims: Dementia biomarkers that are accessible and easily applicable in nonspecialized clinical settings are urgently needed. Quantitative electroencephalography (qEEG) is a good candidate, and the statistical pattern recognition (SPR) method has recently provided promising results. We tested the diagnostic value of qEEG-SPR in comparison to cognition, structural imaging, and cerebrospinal fluid (CSF) biomarkers. Methods: A total of 511 individuals were recruited from the multicenter NORD EEG study [141 healthy controls, 64 subjective cognitive decline, 124 mild cognitive impairment, 135 Alzheimer's disease (AD), 15 dementia with Lewy bodies/Parkinson's disease with dementia (DLB/PDD), 32 other dementias]. The EEG data were recorded in a standardized way. Structural imaging data were visually rated using scales of atrophy in the medial temporal, frontal, and posterior cortex. Results: qEEG-SPR outperformed structural imaging, cognition, and CSF biomarkers in DLB/PDD diagnosis, outperformed structural imaging in AD diagnosis, and improved the differential diagnosis of AD. In addition, qEEG-SPR allowed differentiation of two clinically different AD subtypes. Conclusion: Adding qEEG to the diagnostic workup substantially increases the detection of AD pathology even in pre-dementia stages and improves differential diagnosis. EEG could serve as a good complement to currently established dementia biomarkers since it is cheap, noninvasive, and extensively applied outside academic centers.

Distinct subtypes of Alzheimer’s disease based on patterns of brain atrophy: longitudinal trajectories and clinical applications

“…However, a method to enable their investigation in the clinical routine has been lacking so far. In the current study, visual rating scales were used as subtyping method because they are the primary method for assessing brain structural changes in clinical settings18192021. Although grouped data is reported, the visual rating scales can be applied at the individual level for clinical diagnosis.…”

“…Visual rating scales are quick and easy to use, and are the primary method for assessing brain structural changes in clinical settings18192021. However, visual rating scales are often used individually.…”

Practical use of visual medial temporal lobe atrophy cut-off scores in Alzheimer’s disease: Validation in a large memory clinic population

“…The average of right and left MTA score is suggested as the best marker [12] and recommendations were made for the use of 1.5 under 75 years and 2 or more for those over 75 years as cut-off scores [11]. Only recently has the approach been taken to compute decade-specific MTA cut-off scores optimize sensitivity and specificity [13], and these cut-off scores were used in a recent study on quantitative electroencephalography in addition to dementia biomarkers [27]. We adopted this strategy and tested the results in a memory clinic setting and found comparable results for the middle-age ranges, despite methodological differences including different AD source population (single-centre memory clinic vs. academic centres and private practice), different reference population (patients with SCI versus normal controls), different rating procedure (consensus rating vs. one single rater) and different imaging tool (CT vs. MRI).…”

Complexity Measures for Quantifying Changes in Electroencephalogram in Alzheimer’s Disease

“…The fundamental utility of EEG to detect brain signal changes even in the preclinical stage of the disease has been demonstrated [33,37,38]. Thus, EEG biomarkers may be used as a first-line decision-support tool in AD diagnosis [11,35] and could complement other AD biomarkers [26].…”