Dr. Gesine Hermann (Kiel / DE), Friederike Baumgarte (Kiel / DE), Julius Welzel (Kiel / DE), Dr. rer. hum. biol. Peter Nydahl (Kiel / DE), Prof. Dr. Gregor Kuhlenbäumer (Kiel / DE), PD Dr. Dipl.-Psych. Nils Gerd Margraf (Kiel / DE)
Abstract-Text (inkl. Referenzen und Bildunterschriften)
Background: About 10 percent of patients suffering from an acute stroke get diagnosed with delirium during the associated hospital stay, with older age increasing the risk (Dahl et al. 2010). It is well known that generalized slowing in the electroencephalogram (EEG) supports the diagnosis of delirium (Jacobson & Jerrier, 2000). In this context, we examine the potential of a single-channel EEG as an easy-to-use device on stroke units. Comparison of bihemispheric EEG recordings with a right fronto-parietal EEG channel (DeltaScan®) will be analyzed in context with the clinically established delirium diagnosis.
Methods: Within the first five days after stroke onset, in 9 of 63 patients (25-90 years) a delirium was diagnosed according to DSM-V criteria. All patients received DeltaScan® and a 21 channel EEG recording (200 Hz, avg. reference, impedances ≤ 10 kΩ). Based on 2-minute eyes-closed resting state segments we analyzed power spectral density (PSD) in predefined frequency bands (delta 1-4 Hz, theta 4-8 Hz, alpha 8-12 Hz, beta 15-30 Hz). Analyses were conducted in MNE (v1.3.1), Python (3.10) and RStudio (v4.2.1).
Results: We found patients with right hemispheric stroke having a higher probability to be false positive in DeltaScan® (p=0.01, OR=5.90). EEG based power analysis revealed frontal delta (sensitivity 0.82, CI=0.57-0.97) and left hemispheric frontal theta power (sensitivity 0.86, CI=0.67-0.98) as the best predictors of diagnosed delirium.
Conclusion: When EEG is used in clinical practice to support a delirium diagnosis, bihemispheric recordings should be preferred over unilateral recordings in stroke patients. Slowing in the delta- or theta-frequency spectrum over the site of stroke can lead to false-positive results in single channel EEG based delirium scoring. Emphasis should be given to frontal electrodes of both sides.
Dahl et al. 2010. doi: 10.1111/j.1600-0404.2010.01374.x. PMID: 20586734.
Jacobson & Jerrier, 2000. doi: 10.153/SCNP00500086. PMID: 10837097.