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

Raicher, Irina; Takahashi, Daniel Yasumasa; Kanda, Paulo Afonso Medeiros; Nitrini, Ricardo; Anghinah, Renato

doi:10.1590/S1980-57642009DN20100003

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.

Key words:
quantitative electroencephalography; spectral analysis; dementia; Alzheimer's disease; memory complaint; cognition; qEEG

Resumo

A análise espectral do EEG tem sido considerada muito sensível para mudanças da função cortical e compatível com o diagnóstico clínico da Doença de Alzheimer (DA). A sensibilidade da análise espectral varia de 71% a 81% em alguns estudos.^1-3 Objetivo: A proposta deste estudo foi uma avaliação retrospectiva sobre a possibilidade do pico espectral do alfa no EEG quantitativo (EEGq) complementar o exame clínico fornecendo uma ferramenta independente para monitorizar o tratamento e para seguimento da progressão da demência na DA. Além disso, foram examinados dados demográficos e a distribuição do espectro da potência alfa de pacientes e controles da mesma idade. Métodos: EEGq foram selecionados de dois grupos de pacientes: os controles sem alterações e queixas de memória (n=30) e os pacientes com critérios preenchidos para DA provável (n=41). A análise do pico espectral do alfa no EEGq e o Mini-Exame do Estado Mental foram realizados uma ou duas vezes no ano. Resultados: Neste grupo estudado, o Mini-Exame do Estado Mental e o pico espectral do alfa no EEGq não foram estatisticamente diferentes depois do uso de anticolinesterásicos e o pico espectral do EEGq não foi menor do que 8 Hz em todos indivíduos do grupo controle. Conclusão: Este estudo sustenta dois conceitos importantes. Primeiro, 8 Hz de pico espectral de alfa, em vigília, aparenta ser o menor valor compatível com normalidade. E finalmente, em contexto clínico, EEGq é uma ferramenta que pode ser útil no seguimento da de Demência.

Palavras-chave:
eletroencefalografia quantitative; análise espectral; demência; doença de Alzheimer; queixa de memória; cognição; EEGq

Texto completo disponível apenas em PDF.

Full text available only in PDF format.

References

¹
Loeches MM, Gil P, Jimenez F, et al. Topographic maps of brain electrical activity in primary degenerative dementia of Alzheimer type and multiinfarct dementia. Biol Psych 1991;29:211-223.
²
Dierks T, Perisic I, Frölich L, Ihl R, Maurer K. Topography of the qEEG in dementia of Alzheimer type: relation to severity of dementia. Psych Research 1991;40:181-194.
³
Leuchter AF, Cook IA, Newton TF, et al. Regional differences in brain electrical activity in dementia: use of spectral power and spectral ratio measures. Electroencephalogr clin Neurophysiol 1993;87:385-393.
⁴
McKhann G, Drachman D, Folstein M, Katzman R, Price D, Stadlan EM. Clinical diagnosis of AD: report of the NINCDS-ADRDA work group under the auspices of Department oh health and human services task force on AD. Neurology 1984;34:939-944.
⁵
Diagnostic and Statistical Manual (DSMIII R). 3rd ed. American Psychiatric Association, 1987.
⁶
Folstein MF, Folstein SE, McHugh PR. Mini-Mental State: a practical method for grading the cognitive state of patients for the clinician. J Psych Research 1975;12:189-198.
⁷
Brucki S, Nitrini R, Caramelli P, Bertolucci PHF, Okamoto IH. Suggestions for utilization of the Mini-Mental State Examination in Brazil. Arq Neuropsiquiatr 2003;61:777-781.
⁸
Jasper HH. The ten-twenty electrode system of the International Federation. Electroencephalogr. clin Neurophysiol 1958;10:371-373.
⁹
Hall KS, Gao S, Unverzagt FW, Hendrie HC. Low education and childhood rural residence - Risk for Alzheimer's disease in African Americans. Neurology 2000; 54:95-99.
¹⁰
Roe CM, Xiong C, J. Miller P, Morris JC. Education and Alzheimer disease without dementia. Support for the cognitive reserve hypothesis. Neurology 2007;68:223-228.
¹¹
Babiloni C, Binetti G, Cassetta E, et al. Sources of cortical rhythms change as a function of cognitive impairment in pathological aging: a multicenter study. Clin Neurophysiol 2006;117:252-268.
¹²
Rossini PM, Del Percio C, Pasqualetti P, et al. Conversion from mild cognitive impairment to Alzheimer's disease is predicted by sources and coherence of brain electroencephalography rhythms. Neuroscience 2006;143:793-803.
¹³
Henderson G, Ifeachor E, Hudson N, et al. Development and assessment of methods for detecting dementia using the human electroencephalogram. IEEE Trans Biomed Eng 2006;53:1557-1568.
¹⁴
Yoshimura M, Isotani T, Yagyu T, Irisawa S. Global approach to multichannel electroencephalogram analysis for diagnosis and clinical evaluation in mild Alzheimer´s disease. Neuropsychobiology 2004;49:163-166.
¹⁵
Nobili F, Copello F, Vitali P, et al. Timing of disease progression by quantitative EEG in Alzheimer's patients. J Clin Neurophysiol 1999;16:566-573.
¹⁶
Sneddon R, Shankle WR, Hara J, Rodriquez A, Hoffman D, Saha U. QEEG monitoring of Alzheimer's disease treatment: A preliminary report of three case studies. Clin EEG Neurosci. 2006;37:54-59.
¹⁷
Kogan EA, Korczyn AD, Virchovsky RG, Klimovizky SS, Treves TA, Neufeld MY. EEG changes during long-term treatment with donepezil in Alzheimer's disease patients. M.Y. J Neural Transm 2001;108:1167-1173.
¹⁸
Reeves RR, Struve FA, Patrick G. The effects of donepezil on quantitative EEG in patients with Alzheimer's disease. Clin Electroencephalogr. 2002;33:93-96.

Publication Dates

Publication in this collection
Jan-Mar 2008

History

Received
13 Jan 2008
Reviewed
09 Feb 2008
Accepted
27 Feb 2008

This is an open-access article distributed under the terms of the Creative Commons Attribution License

[1] ¹
Loeches MM, Gil P, Jimenez F, et al. Topographic maps of brain electrical activity in primary degenerative dementia of Alzheimer type and multiinfarct dementia. Biol Psych 1991;29:211-223.

[2] ²
Dierks T, Perisic I, Frölich L, Ihl R, Maurer K. Topography of the qEEG in dementia of Alzheimer type: relation to severity of dementia. Psych Research 1991;40:181-194.

[3] ³
Leuchter AF, Cook IA, Newton TF, et al. Regional differences in brain electrical activity in dementia: use of spectral power and spectral ratio measures. Electroencephalogr clin Neurophysiol 1993;87:385-393.

[4] ⁴
McKhann G, Drachman D, Folstein M, Katzman R, Price D, Stadlan EM. Clinical diagnosis of AD: report of the NINCDS-ADRDA work group under the auspices of Department oh health and human services task force on AD. Neurology 1984;34:939-944.

[5] ⁵
Diagnostic and Statistical Manual (DSMIII R). 3rd ed. American Psychiatric Association, 1987.

[6] ⁶
Folstein MF, Folstein SE, McHugh PR. Mini-Mental State: a practical method for grading the cognitive state of patients for the clinician. J Psych Research 1975;12:189-198.

[7] ⁷
Brucki S, Nitrini R, Caramelli P, Bertolucci PHF, Okamoto IH. Suggestions for utilization of the Mini-Mental State Examination in Brazil. Arq Neuropsiquiatr 2003;61:777-781.

[8] ⁸
Jasper HH. The ten-twenty electrode system of the International Federation. Electroencephalogr. clin Neurophysiol 1958;10:371-373.

[9] ⁹
Hall KS, Gao S, Unverzagt FW, Hendrie HC. Low education and childhood rural residence - Risk for Alzheimer's disease in African Americans. Neurology 2000; 54:95-99.

[10] ¹⁰
Roe CM, Xiong C, J. Miller P, Morris JC. Education and Alzheimer disease without dementia. Support for the cognitive reserve hypothesis. Neurology 2007;68:223-228.

[11] ¹¹
Babiloni C, Binetti G, Cassetta E, et al. Sources of cortical rhythms change as a function of cognitive impairment in pathological aging: a multicenter study. Clin Neurophysiol 2006;117:252-268.

[12] ¹²
Rossini PM, Del Percio C, Pasqualetti P, et al. Conversion from mild cognitive impairment to Alzheimer's disease is predicted by sources and coherence of brain electroencephalography rhythms. Neuroscience 2006;143:793-803.

[13] ¹³
Henderson G, Ifeachor E, Hudson N, et al. Development and assessment of methods for detecting dementia using the human electroencephalogram. IEEE Trans Biomed Eng 2006;53:1557-1568.

[14] ¹⁴
Yoshimura M, Isotani T, Yagyu T, Irisawa S. Global approach to multichannel electroencephalogram analysis for diagnosis and clinical evaluation in mild Alzheimer´s disease. Neuropsychobiology 2004;49:163-166.

[15] ¹⁵
Nobili F, Copello F, Vitali P, et al. Timing of disease progression by quantitative EEG in Alzheimer's patients. J Clin Neurophysiol 1999;16:566-573.

[16] ¹⁶
Sneddon R, Shankle WR, Hara J, Rodriquez A, Hoffman D, Saha U. QEEG monitoring of Alzheimer's disease treatment: A preliminary report of three case studies. Clin EEG Neurosci. 2006;37:54-59.

[17] ¹⁷
Kogan EA, Korczyn AD, Virchovsky RG, Klimovizky SS, Treves TA, Neufeld MY. EEG changes during long-term treatment with donepezil in Alzheimer's disease patients. M.Y. J Neural Transm 2001;108:1167-1173.

[18] ¹⁸
Reeves RR, Struve FA, Patrick G. The effects of donepezil on quantitative EEG in patients with Alzheimer's disease. Clin Electroencephalogr. 2002;33:93-96.

Brasil