P136. Relation of EEG frequency and apathy in patients with Parkinson's disease (PD). Issue 8 (August 2015)

• Record Type: Journal Article
• Authors: Meyer, A.; Bousleiman, H.; Chaturvedi, M.; Hatz, F.; Nowak, K.; Zimmermann, R.; Fuhr, P.; Gschwandtner, U.
• Is Part Of: Clinical neurophysiology. Volume 126:Issue 8(2015:Aug.)
• Page Start: e155
• Page End: 254
• Publication Date: 2015-08
• Subjects: Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2015.04.259
• Languages: English
• ISSNs: 1388-2457

Abstract

<abstract xml:lang="en" abstract-type="author" id="ab005"> <title> <x xml:space="preserve">Abstract</x> </title> <sec> <title id="st005">Objective</title> <p id="sp005">To examine the hypothesis that apathy in patients with PD is related to frontal and temporal changes in EEG frequencies. We expected apathy to correlate with slowing of general EEG background activity, with decrease of alpha power and with increase of theta power in frontal and temporal regions of the brain.</p> </sec> <sec> <title id="st010">Methods</title> <p id="sp010">37 non-demented patients with idiopathic PD were recruited from the Movement Disorder Outpatient Clinic Basel (age: <italic>Median</italic> 69 y; from 50 y to 84 y; 14 females). The Apathy Evaluation Scale (AES) (<xref id="c0005" rid="b0005">Marin, 1991</xref>) in informant version (AES-I) were completed by relatives of the patients.256-channel EEGs with quantitative semi-automatic analyses were used to detect alpha total-frequencies alpha 1-, alpha 2- and theta-in frontal and temporal regions. In addition, slowing of EEG was measured with Median Peak frequency. For statistics, a general linear model with backward elimination procedure was conducted. We controlled for confounding factors: age, gender, education, severity of motor symptoms, levodopa equivalent dose, depression and cognition.</p> </sec> <sec> <title id="st015">Results</title> <p id="sp015">In this sample, the patients were only slightly affected by apathy (<italic>Median</italic> = 24; from 18 to 39; cut off value: 38). The resulting model was significant (<inline-formula><alternatives><inline-graphic xlink:href="ark:/27927/pgj1f28fx2n" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math altimg="si1.gif" overflow="scroll" id="d13e143" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:mi>R</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msup><mml:mo>=</mml:mo><mml:mn>0.39</mml:mn></mml:mrow></mml:math></alternatives></inline-formula>; <italic>p</italic> < 0.01). Backward procedure eliminated the variables for age, education, severity of motor symptoms, levodopa equivalent dose, depression, and cognition. Only gender showed a trend as a confounder in the model (<italic>b</italic> = −3.74; <italic>p</italic> = 0.08). Relevant variables in the resulting model were alpha total, temporal right (<italic>b</italic> = 76.493; <italic>p</italic> < 0.01), alpha 1, frontal left (<italic>b</italic> = −58.37; <italic>p</italic> < 0.05) and Median Peak frequency (<italic>b</italic> = −13.07; <italic>p</italic> < 0.01). The analyses of gender revealed a stronger interaction in male of apathy and alpha total decline in this sample (<italic>r</italic> = −0.40), whereas in females there was no correlation between alpha total and the number of apathy symptoms (<italic>r</italic> = 0.04).</p> </sec> <sec> <title id="st020">Conclusions</title> <p id="sp020">Slowing of EEG is correlated with apathy in patients with PD. This correlation is significant even in PD patients with little or no depression. This fact helps to separate the two neuropsychiatric entities. In accordance with our hypothesis, beginning apathy in PD might be related to an alpha 1 decrease the frontal left part of the brain. In contrast, alpha total of the right hemisphere positively correlates with apathy. In addition, however, the results in male gender are consistent with our expectation, but have to be replicated in a larger sample of PD patients with more severe apathy.</p> </sec> </abstract>