Resting State Cortical Electroencephalographic Rhythms and White Matter Vascular Lesions in Subjects with Alzheimer's Disease: An Italian Multicenter Study

Article type: Research Article

Authors: Babiloni, Claudio^{a; b; *} | Lizio, Roberta^c | Carducci, Filippo^d | Vecchio, Fabrizio^e | Redolfi, Alberto^f | Marino, Silvia^g | Tedeschi, Gioacchino^{h; i} | Montella, Patrizia^h | Guizzaro, Antonio^h | Esposito, Fabrizio^j | Bozzao, Alessandro^k | Giubilei, Franco^k | Orzi, Francesco^k | Quattrocchi, Carlo C.^l | Soricelli, Andrea^m | Salvatore, Elenaⁿ | Baglieri, Annalisa^g | Bramanti, Placido^g | Cavedo, Enrica^f | Ferri, Raffaele^o | Cosentino, Filomena^o | Ferrara, Michelangelo^o | Mundi, Ciro^p | Grilli, Gianpaolo^p | Pugliese, Silvia^k | Gerardi, Gianluca^d | Parisi, Laura^e | Vernieri, Fabrizio^q | Triggiani, Antonio I.^a | Pedersen, Jan T.^r | Hårdemark, Hans-Göran^s | Rossini, Paolo M.^{b; t} | Frisoni, Giovanni B.^f

Affiliations: [a] Department of Biomedical Sciences, University of Foggia, Foggia, Italy | [b] Department of Imaging, SAN RAFFAELE Cassino, Italy | [c] IRCCS San Raffaele Pisana, Rome, Italy | [d] Laboratory of Neuroimaging, Department of Physiology and Pharmacology, University of Rome, “Sapienza”, Rome, Italy | [e] A.Fa.R., Department of Neuroscience Ospedale FBF; Isola Tiberina, Rome, Italy | [f] IRCCS “S. Giovanni di Dio-F.B.F.”, Brescia, Italy | [g] IRCCS Centro Neurolesi “Bonino-Pulejo” – Messina, Italy | [h] Department of Neurological Sciences, Second University of Naples, Naples, Italy | [i] Neurological Institute for Diagnosis and Care “Hermitage Capodimonte”, Naples, Italy | [j] Department of Neuroscience, University of Naples “Federico II”, Naples, Italy | [k] Department of Neuroscience, Mental Health and Sensory Organs, University of Rome “La Sapienza”, Roma, Italy | [l] IRCCS “Ospedale Pediatrico Bambino Gesù”, Roma, Italy | [m] Fondazione SDN per la Ricerca e l'Alta Formazione in Diagnostica Nucleare, IRCCS Naples, Italy | [n] Department of Neurological Sciences, University of Naples “Federico II”, Naples, Italy | [o] IRCCS Oasi, Troina (Enna), Italy | [p] Department of Neuroscience, Ospedali Riuniti di Foggia, Foggia, Italy | [q] Neurol. University “Campus Biomedico” Rome, Italy | [r] Section Head, Bioinformatics, H. Lundbeck A/S, Valby, Denmark | [s] AstraZeneca R&D, Clinical Neuroscience, Södertälje, Sweden | [t] Neurology Catholic University “Sacro Cuore” Rome, Italy

Correspondence: [*] Correspondence to: Prof. Claudio Babiloni, PhD, Department of Biomedical Sciences, University of Foggia, Viale Pinto 7, Foggia I-71100, Italy. Tel. and Fax: +39 0881 713276 (1716); E-mail: [email protected].

Abstract: Resting state electroencephalographic (EEG) rhythms do not deteriorate with the increase of white matter vascular lesion in amnesic mild cognitive impairment (MCI) subjects [1], although white matter is impaired along Alzheimer's disease (AD). Here we tested whether this is true even in AD subjects. Closed-eye resting state EEG data were recorded in 40 healthy elderly (Nold), 96 amnesic MCI, and 83 AD subjects. White matter vascular lesions were indexed by magnetic resonance imaging recorded in the MCI and AD subjects (about 42% of cases following ADNI standards). The MCI subjects were divided into two sub-groups based on the median of the white matter lesion, namely MCI+ (people with highest vascular load; n = 48) and MCI− (people with lowest vascular load; n = 48). The same was true for the AD subjects (AD+, n = 42; AD−, n = 41). EEG rhythms of interest were delta (2–4 Hz), theta (4–8 Hz), alpha1 (8–10.5 Hz), alpha2 (10.5–13 Hz), beta1 (13–20 Hz), beta2 (20–30 Hz), and gamma (30–40 Hz). LORETA software estimated cortical EEG sources. When compared to Nold group, MCI and AD groups showed well known abnormalities of delta and alpha sources. Furthermore, amplitude of occipital, temporal, and limbic alpha 1 sources were higher in MCI+ than MCI− group. As a novelty, amplitude of occipital delta sources was lower in AD+ than AD− group. Furthermore, central, parietal, occipital, temporal, and limbic alpha sources were higher in amplitude in AD+ than AD− group. Amplitude of these sources was correlated to global cognitive status (i.e., Mini Mental State Evaluation score). These results suggest that in amnesic MCI and AD subjects, resting state posterior delta and alpha EEG rhythms do not deteriorate with the increase of white-matter vascular lesion. These rhythms might be more sensitive to AD neurodegenerative processes and cognitive status rather than to concomitant lesions to white matter.

Keywords: Alzheimer's disease, Alzheimer's disease neuroimaging initiative, amnesic mild c cognitive impairment, electroencephalographic rhythms, low resolution brain electromagnetic tomography, magnetic resonance imaging, resting state, white matter vascular lesion

DOI: 10.3233/JAD-2011-101710

Journal: Journal of Alzheimer's Disease, vol. 26, no. 2, pp. 331-346, 2011