On the edge of awareness: ictal consciousness and psychosis in focal epilepsy
A. Tarrada, S. BaltassisIntroduction
Psychoses of epilepsy (POE) are psychotic disorders arising after epilepsy onset, affecting up to 13% of patients with focal epilepsy. Based on their temporal relationship with seizures, POE is classified as peri-ictal psychosis —with postictal psychosis (PIP) being most common—or interictal psychosis. These subtypes often overlap within the same patients, suggesting shared mechanisms.
Objectives
While interictal risk factors are well documented, ictal correlates remain poorly characterized. This study assessed the association between objective ictal features, ictal consciousness and POE.
Methods
We included 112 patients with drug-resistant focal epilepsy who underwent epilepsy-specific psychiatric assessment and long-term video-EEG or stereo-EEG (S-EEG) monitoring. Seizure semiology and epilepsy features were compared between patients with (n = 15) and without POE (n = 97). Ictal consciousness was assessed using the Consciousness Seizure Scale(CSS). For analysis, CSS scores were categorized into three levels: 0–1 (preserved consciousness), 2–6 (altered), and 7–9 (abolished). Seizure onset zones were examined in S-EEG patients (n = 37).
Results
POE was associated with altered ictal consciousness (p = .04), following a non-linear pattern peaking at intermediate CSS scores (p = .015). POE patients were older (p = .005), had longer epilepsy duration (p= .005), and higher depression (p= .002) and anxiety scores (p =.001). Non-significant trends were found for lateral epilepsy (p = .07) and learning disabilities (p= .06).
Image 1: Long description.