Feasibility and potential of a bedside mini-EEG for diagnosing delirium superimposed on dementia. (October 2022)

• Record Type: Journal Article
• Authors: Wijnen, Viona J.M.; Oudewortel, Letty; van Luijtelaar, Gilles; Witlox, Joost; Slooter, Arjen J.C.; van Gool, Willem.A.
• Is Part Of: Clinical neurophysiology. Volume 142(2022)
• Page Start: 181
• Page End: 189
• Publication Date: 2022-10
• Subjects: Delirium superimposed on dementia -- Delirium -- Dementia -- Neurocognitive disorders -- EEG -- Encephalopathy; CAM-ICU confusion assessment method for the intensive care unit -- DSD delirium superimposed on dementia -- DS-DAT discomfort scale-dementia of Alzheimer type -- DSM-5 5th version of the diagnostic and statistical manual of mental disorders -- EEG electroencephalography -- FFT fast fourier transformation -- GDS global deterioration scale for assessment of primary degenerative dementia -- OSLA observational scale of level of arousal -- PAF peak alpha frequency -- ROC receiver operating curve; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2022.08.002
• Languages: English
• ISSNs: 1388-2457

Abstract

Highlights: A brief point-of-care EEG is of promising diagnostic accuracy for recognizing delirium where superimposed on dementia (DSD). The EEG of patients with DSD is characterized by increased slower activity compared to dementia patients without delirium. Results indicate that EEG characteristics are associated with recovery or deterioration of delirium in DSD. Abstract: Objective: Delirium superimposed on dementia (DSD) is difficult to diagnose because symptoms of delirium might be interpreted as symptoms of dementia. To improve diagnostic accuracy, we investigated the potential of a brief point-of-care EEG measurement. Methods: Thirty older patients were included, all with Major Neurocognitive Disorder (i.e. dementia) according to DSM-5 criteria. EEG was registered at right prefrontal and right temporal site, with eyes either open or closed for three minutes, simultaneously with the Discomfort Scale for Dementia of Alzheimer Type. The Confusion Assessment Method for the Intensive Care Unit was administered to determine the presence of symptoms of a delirium at the time of EEG administration. Video registrations were reviewed independently by two delirium experts. Results: Higher activities of delta and theta1, and lower activities of theta2, alpha, and beta activity, were found in DSD when compared to dementia only. The ratio of delta and theta power during eyes-open conditions had the highest accuracy (AUC = 0.80 [0.63–0.94]; p <.001) to distinguish DSD from dementia alone. All subjects were on benzodiazepines and half on clozapine, thus the effects of psychotropics on EEG cannot be fully excluded. Conclusions: A brief point-of-care EEG at two sites of the head has the potential to aid in the detection of DSD. Significance: The diagnostic accuracy of EEG in recognizing or excluding delirium in patients who already have dementia is of large potential given the lack of proper diagnostic tools.