Comparison of Standard and Extended 3-Hour EEG in Elderly with Acute Confusion

Purpose: Several studies have been conducted to ascertain the efficacy of continuous EEG (cEEG) in elderly patients presenting with acute confusion state (ACS). These studies have yielded preliminary evidence suggesting that cEEG may offer superior detection of NCSz and NCSE compared to standard EEG. The objective was to assess whether a 3-hour EEG could yield more data than a 20-minute standard EEG, particularly in terms of identifying epileptiform discharges (ED) and other pathological findings in elderly individuals with acute confusion of unknown origin at the onset of their symptoms in resource – restricted settings.
Method: Prospective observational study of 40 elderly patients presenting with ACS of unknown etiology underwent 20-minute, 30-minute and 3-hour EEG recording.
Results: There were no statistically significant differences in EEG patterns between the 20-minute, 30-minute, and 3-hour EEG groups (p > 0.05). No clinical, laboratory, or neuroimaging markers were identified as prognostic indicators of epileptic EEG patterns.
Conclusion: A prolonged 3-hour EEG does not provide additional benefits for the older patient population with an acute confusional state of unknown etiology. When present, specific EEG changes suggestive of non-convulsive seizures (NCSz) or non-convulsive status epilepticus (NCSE) can be identified within the standard 20-minute EEG recording period.