Abstracts

Rationale: Epilepsy is a chronic noncommunicable disease of the brain that affects people all ages. Around 50 million people worldwide have epilepsy making it one of the most neurological diseases globally. Post-traumatic epilepsy (PTE) is the archetype of acquired epilepsies, wherein a brain insult initiates an epileptogenic process culminating in an unprovoked seizure after weeks, months or years. PTE develops in as many as one-third of severe traumatic brain injury (TBI) patients. Identifying biomarkers on electroencephalography (EEG) of such a process is a prerequisite for developing and implementing targeted therapies aimed at preventing the development of epilepsy. Our objective was to find out biomarkers on the EEG of the upcoming or possible development of epilepsy in a patient after a TBI.

Methods: We selected patients who had once received a traumatic brain injury and divided them into two groups. The first group consists of patients with post-traumatic epilepsy and the second without epilepsy. All these patients treated at the Neurosurgery and Neurology departments of the Osh city clinical hospital from 2015 through 2022. All patients underwent continuous EEG for two to three hours. After several years, patients without PTE were re-examined. A board-certified neurophysiologist described EEG features using standardized descriptions. We extracted differences on EEG between two groups, and described them with qualitative statistics.

Results: We identified 189 patients: 93 with PTE and 96 without epilepsy. Patients with PTE: EEG findings of background alpha activity was high combined with sharp waves - 42 patients; PTE cohort had higher spectral power in the delta frequencies, more power variance in the delta and theta frequencies combined with spikes - 51. Patients without epilepsy on EEG had high-frequency alpha activity in the posterior regions - 37 (38,54%) patients; low-amplitude alpha activity and the prevalence of theta and delta activity - 36 (37,50%); low-amplitude alpha activity and the prevalence of theta and delta activity combined with spikes and peaks - 23 (23,95%). When re-examining patients without epilepsy several years after the first examination; of these 23 patients with low-amplitude alpha activity and the prevalence of theta and delta activity combined with spikes and peaks, 19 (82,60%) developed PTE.

Conclusions: Our studies show that 19,79% of patients with brain injury developed PTE and 82,60% of patients with brain injury with changes in the EEG like low-amplitude alpha activity and the prevalence of theta and delta activity combined with spikes and peaks developed PTE in the clinic. The group with these EEG changes has the highest risk to develop PTE. Our results highlight the potential benefit of early EEG assessments in TBI patients.

Funding: None.