qEEG spectral peak in Alzheimer's disease: A possible tool for treatment follow-up

• Main Authors: Irina Raicher, Daniel Yasumasa Takahashi, Paulo Afonso Medeiros Kanda, Ricardo Nitrini, Renato Anghinah
• Format: Article
• Language: English
• Published: Associação Neurologia Cognitiva e do Comportamento
• Series: Dementia & Neuropsychologia
• Subjects: quantitative electroencephalography; spectral analysis; dementia; Alzheimer's disease; memory complaint; cognition; qEEG
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1980-57642008000100009&lng=en&tlng=en

Abstract qEEG spectral analysis has been considered highly sensitive to cortical functional changes and agrees strongly with the clinical diagnosis of AD. The sensitivity of spectral analysis has ranged from 71% to 81% in several studies.1-3. Objective: The aim of this study was to retrospectively evaluate whether alpha qEEG spectral peak can supplement clinical examination by constituting an independent tool to monitor treatment and follow-up of dementia progression in Alzheimer's disease (AD). In addition, we examined the demographic data and alpha power spectra distribution of patients and elderly normal controls. Methods: qEEGs were selected from 2 groups of patients: normal controls (n=30), and patients who fulfilled criteria for mild probable AD diagnosis (n=41). The alpha qEEG spectral analysis and MMSE were performed once or twice a year. Results: In our groups, MMSE scores and qEEG alpha spectral peak were unchanged (no statistical differences) after anticholinesterase use where qEEG spectral peak was never lower than 8 Hz in the control group. Conclusion: This study supports two important concepts. First, 8 Hz alpha appears to be the lowest awake spectral peak compatible with normality. And finally, in a clinical context, qEEG is a valuable diagnostic tool that could prove useful for Dementia follow-up.