TY - JOUR
T1 - Cortical excitation/inhibition ratios in patients with major depression treated with electroconvulsive therapy
T2 - an EEG analysis
AU - Stuiver, Sven
AU - Pottkämper, Julia C. M.
AU - Verdijk, Joey P. A. J.
AU - ten Doesschate, Freek
AU - Aalbregt, Eva
AU - van Putten, Michel J. A. M.
AU - Hofmeijer, Jeannette
AU - van Waarde, Jeroen A.
N1 - Funding Information: This work was supported by the Dutch National Epilepsy Fund [EpilepsieNL; Grant number WAR 19-02]. Publisher Copyright: © 2023, The Author(s).
PY - 2023
Y1 - 2023
N2 - Electroconvulsive therapy (ECT) is an effective treatment for major depression, but its working mechanisms are poorly understood. Modulation of excitation/inhibition (E/I) ratios may be a driving factor. Here, we estimate cortical E/I ratios in depressed patients and study whether these ratios change over the course of ECT in relation to clinical effectiveness. Five-minute resting-state electroencephalography (EEG) recordings of 28 depressed patients were recorded before and after their ECT course. Using a novel method based on critical dynamics, functional E/I (fE/I) ratios in the frequency range of 0.5–30 Hz were estimated in frequency bins of 1 Hz for the whole brain and for pre-defined brain regions. Change in Hamilton Depression Rating Scale (HDRS) score was used to estimate clinical effectiveness. To account for test–retest variability, repeated EEG recordings from an independent sample of 31 healthy controls (HC) were included. At baseline, no differences in whole brain and regional fE/I ratios were found between patients and HC. At group level, whole brain and regional fE/I ratios did not change over the ECT course. However, in responders, frontal fE/I ratios in the frequencies 12–28 Hz increased significantly (p FDR < 0.05 [FDR = false discovery rate]) over the ECT course. In non-responders and HC, no changes occurred over time. In this sample, frontal fE/I ratios increased over the ECT course in relation to treatment response. Modulation of frontal fE/I ratios may be an important mechanism of action of ECT.
AB - Electroconvulsive therapy (ECT) is an effective treatment for major depression, but its working mechanisms are poorly understood. Modulation of excitation/inhibition (E/I) ratios may be a driving factor. Here, we estimate cortical E/I ratios in depressed patients and study whether these ratios change over the course of ECT in relation to clinical effectiveness. Five-minute resting-state electroencephalography (EEG) recordings of 28 depressed patients were recorded before and after their ECT course. Using a novel method based on critical dynamics, functional E/I (fE/I) ratios in the frequency range of 0.5–30 Hz were estimated in frequency bins of 1 Hz for the whole brain and for pre-defined brain regions. Change in Hamilton Depression Rating Scale (HDRS) score was used to estimate clinical effectiveness. To account for test–retest variability, repeated EEG recordings from an independent sample of 31 healthy controls (HC) were included. At baseline, no differences in whole brain and regional fE/I ratios were found between patients and HC. At group level, whole brain and regional fE/I ratios did not change over the ECT course. However, in responders, frontal fE/I ratios in the frequencies 12–28 Hz increased significantly (p FDR < 0.05 [FDR = false discovery rate]) over the ECT course. In non-responders and HC, no changes occurred over time. In this sample, frontal fE/I ratios increased over the ECT course in relation to treatment response. Modulation of frontal fE/I ratios may be an important mechanism of action of ECT.
KW - Electroconvulsive therapy
KW - Electroencephalography
KW - Excitation/inhibition ratio
KW - Major depression
UR - http://www.scopus.com/inward/record.url?scp=85176544050&partnerID=8YFLogxK
U2 - https://doi.org/10.1007/s00406-023-01708-5
DO - https://doi.org/10.1007/s00406-023-01708-5
M3 - Article
C2 - 37947826
SN - 0940-1334
JO - European archives of psychiatry and clinical neuroscience
JF - European archives of psychiatry and clinical neuroscience
ER -