EEG Markers of Dementia with Lewy Bodies: A Multicenter Cohort Study

Article type: Research Article

Authors: Bonanni, Laura^{a; *} | Franciotti, Raffaella^a | Nobili, Flavio^b | Kramberger, Milica G.^c | Taylor, John-Paul^d | Garcia-Ptacek, Sara^e | Falasca, N. Walter^f | Famá, Francesco^b | Cromarty, Ruth^d | Onofrj, Marco^a | Aarsland, Dag^g | on behalf of the E-DLB study group^*

Affiliations: [a] Department of Neuroscience, Imaging and Clinical Science, and Aging Research Centre, G. d’Annunzio University of Chieti-Pescara, Chieti, Italy | [b] Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa and IRCCS AOU San Martino-IST, Genoa, Italy | [c] Department of Neurology, University Medical Centre, Ljubljana, Slovenia | [d] Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK | [e] Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Clinical Geriatrics, Karolinska Institutet, and Memory Clinic Department of Geriatric Medicine, Karolinska University Hospital, Stockholm, Sweden | [f] BIND – Behavioral Imaging and Neural Dynamics Center, G. d’Annunzio University of Chieti-Pescara, Chieti, Italy | [g] King’s College of London, London, UK

Correspondence: [*] Correspondence to: Laura Bonanni, Department of Neuroscience and Imaging, G. d’Annunzio University of Chieti-Pescara, Via dei Vestini, 66100 Chieti, Italy. Tel./Fax: +39 0871 562019; E-mail: l.bonanni@unich.it.

Abstract: Quantitative EEG (QEEG) has demonstrated good discriminative capacity for dementia with Lewy bodies (DLB) diagnosis as compared to Alzheimer’s disease (AD) with a predictive value of 100% in a single cohort study. EEG in DLB was characterized by a dominant frequency (DF) in pre-alpha (5.5–7.5 Hz), theta, or delta bands and DF variability (DFV) >1.2 Hz, frequency prevalence (FP) pre-alpha in >40% and FP alpha in <32% of the epochs. To validate the aforementioned QEEG findings in independent cohorts of clinically diagnosed DLB versus AD patients, we analyzed EEG traces of 79 DLB and 133 AD patients (MMSE >20) collected from four European Centers. EEG traces from 19 scalp derivations were acquired as at least 10 min continuous signals and epoched in off-setting as series of 2-second-long epochs, subsequently processed by Fast Fourier Transform (frequency resolution 0.5 Hz). DLB patients showed EEG specific abnormalities in posterior derivations characterized by DF <8 Hz FP pre-alpha >50%, FP alpha <25%. DFV was >0.5 Hz. AD patients displayed stable alpha DF, DFV <0.5 Hz, FP pre-alpha <30%, and FP alpha >55%. DLB and AD differed for DF (p < 10–6), DFV (p < 0.05), FP pre-alpha (p < 10–12) and FP alpha (p < 10–12). Discriminant analysis detected specific cut-offs for every EEG mathematical descriptor; DF = 8, DFV = 2.2 Hz, FP pre-alpha=33%, FP alpha = 41% for posterior derivations. If at least one of the cut-off values was met, the percentage of DLB and AD patients correctly classified was 90% and 64%, respectively. The findings in this multicenter study support the validity of QEEG analysis as a tool for diagnosis in DLB patients.

Keywords: Dementia with Lewy bodies, quantitative EEG

DOI: 10.3233/JAD-160435

Journal: Journal of Alzheimer's Disease, vol. 54, no. 4, pp. 1649-1657, 2016