Evidence mapPaperPMID 42421783Full record

ArticleBJA open2026

Peak alpha frequency and spectral exponent in postoperative delirium: a high-density EEG cohort study.

Klevest Gjini, David Kunkel, Matthew I Banks, Robert A Pearce, Richard Lennertz, Robert D Sanders

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Article in BJA open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Klevest GjiniDepartment of Neurology, University of Wisconsin-Madison, Madison, WI, USA.
David KunkelDepartment of Anesthesiology, University of Wisconsin-Madison, Madison, WI, USA.
Matthew I BanksDepartment of Anesthesiology, University of Wisconsin-Madison, Madison, WI, USA.
Robert A PearceDepartment of Anesthesiology, University of Wisconsin-Madison, Madison, WI, USA.
Richard LennertzDepartment of Anesthesiology, University of Wisconsin-Madison, Madison, WI, USA.
Robert D SandersDepartment of Anaesthetics & Institute of Academic Surgery, Royal Prince Alfred Hospital, Camperdown, Australia.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background: Present concepts around the neurophysiology of delirium suggest impairments in excitatory/inhibitory balance, leading to EEG slowing, altered synaptic activity and integration of information. We aim to clarify the mechanisms involved, hypothesising that, in postoperative delirium, the EEG peak alpha frequency (PAF; decreased peak frequency indicating slowing in alpha frequency) would slow and the spectral exponent (SE; a higher slope indicating an increased neural inhibitory tone) would be steeper compared with a baseline collected before surgery. The primary aim was to determine the association of PAF and SE with postoperative delirium. The secondary aim was to determine the association of perioperative changes in inflammation and executive function with PAF and SE. Methods: High-density 256-channel EEG data were collected perioperatively (i.e. obtained pre-, post-, after 1-yr post-surgery) in a cohort study of 202 patients aged >65 yr undergoing major surgery conducted from 2015 to 2025 at a major quaternary care hospital. Thirty-three participants experienced postoperative delirium, 169 participants did not, with 113 participants followed up at the 1-yr interval. Linear mixed-effects modelling was conducted for PAF and SE estimates. Further analyses tested associations of PAF and SE with the Delirium Rating Scale, Trail Making Test-B (TMT-B) and plasma cytokine levels. Results: After surgery, mean PAF was significantly slower and mean SE was significantly steeper compared with preoperative and 1-yr postoperative values ( Conclusions: Lower mean PAF and steeper SE are consistent with slower neuronal repolarisation and increased inhibition in delirium. PAF and SE estimates provide new information about delirium pathophysiology and could be further explored as noninvasive EEG biomarkers of detection and monitoring of delirium state.

Indexed as

centre of gravity frequencyEEG topographyhigh-density EEGpeak alpha frequencypostoperative deliriumproinflammatory cytokinesspectral exponenttrail-making cognitive test

Identifiers

PMID42421783
PMCPMC13343001

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.