Electroencephalographic Response to Pharmacologic Treatments in DEE-SWAS: A Retrospective Cohort Study Using Sleep-Wake Spike Index Analysis
Abstract number :
2.177
Submission category :
3. Neurophysiology / 3C. Other Clinical EEG
Year :
2025
Submission ID :
602
Source :
www.aesnet.org
Presentation date :
12/7/2025 12:00:00 AM
Published date :
Authors :
Presenting Author: Khaled Al-Robaidi, MD – Division of Neurology - Dayton Children's Hospital
Xiaoming Zhang, PhD – Pediatric Epilepsy Section, Epilepsy Center at the Cleveland Clinic Neurological Institute, Cleveland, OH, USA
Maksim Parfyonov, MD – Pediatric Epilepsy Section, Epilepsy Center at the Cleveland Clinic Neurological Institute, Cleveland, OH, USA
Ajay Gupta, MD – Cleveland Clinic
Deepak Lachhwani, MD – Cleveland Clinic
Kotagal Prakash, MD – Neurological Institute - Cleveland Clinic
Elia Pestana Knight, MD – Cleveland Clinic
Rationale: Developmental/Epileptic Encephalopathy with Spike Wave Activation in Sleep (DEE-SWAS) is characterized by cognitive and behavioral regression accompanied by potentiation of epileptiform discharges during non-rapid eye movement (NREM) sleep. Although multiple treatment strategies exist, comparative evidence on their electroencephalographic (EEG) impact remains limited.
Methods: We retrospectively analyzed pediatric patients diagnosed with Electrical Status Epilepticus in Sleep (ESES) at Cleveland Clinic between 2012 and 2022. Spike wave counts were manually quantified in 100-second epochs during wakefulness, N2, and N3/4 sleep stages from paired pre- and post-treatment EEGs. A novel Spike Wave Index (SWI) was computed by subtracting the awake spike count from sleep-stage spike counts to better capture sleep activation, which can be masked by widespread interictal abnormalities, particularly in developmental and epileptic encephalopathies. Treatments were categorized into anti-seizure medication (ASM)-based, steroid-based, and high-dose diazepam groups. Paired comparisons were assessed using Wilcoxon signed-rank tests, and group differences were evaluated with Kruskal-Wallis tests.
Results: Forty patients were included (mean age at epilepsy onset: 3.1 ± 2.7 years; ESES diagnosis: 7.0 ± 2.4 years). Following treatment, median SWI significantly decreased in both N2 (from 57.5% to 37.0%; p = 0.022) and N3/4 sleep (from 61.0% to 40.5%; p = 0.041). When stratified by etiology, patients with self-limited focal epilepsies (SeLFE) showed greater reductions in N2 SWI (median reduction = 19%, p = 0.047) compared to those with other etiologies (median reduction = 1.5%, p = 0.26). Sensitivity analysis including only patients with follow-up EEGs ≤90 days (n = 15) showed similar trends but did not reach statistical significance. Among treatment groups, diazepam-only therapy yielded the largest reductions in both N2 (median reduction = 47%) and N3/4 indices (median reduction = 45%), but between-group differences were not statistically significant (N2: p = 0.45; N3/4: p = 0.25), likely due to small sample sizes and response variability.
Conclusions: Pharmacologic treatment of DEE-SWAS was associated with a significant reduction in sleep-activated spike burden, particularly in patients with SeLFE. A sleep-wake index approach improved differentiation of sleep-potentiated discharges, especially in cases with diffuse interictal activity. While no single treatment emerged as statistically superior, diazepam showed the most promising EEG improvements. These findings support the need for individualized treatment planning and larger prospective studies to determine optimal strategies.
Funding: N/A
Neurophysiology