Medication Adjustment in Juvenile Absence Epilepsy (JAE) Shows Interictal Discharges Burst During Sleep Suggesting Coupling to a Sleep-phase Generator
Abstract number :
1.172
Submission category :
3. Neurophysiology / 3C. Other Clinical EEG
Year :
2022
Submission ID :
2204891
Source :
www.aesnet.org
Presentation date :
12/3/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:26 AM
Authors :
Peter Hingston, – St Vincent's Hospital Melbourne; Anita Dharan, B. Sc (Psychology & Psychophysiology), B. Sc (Hons) – Melbourne School of Psychological Sciences – The University of Melbourne; Ewan Nurse, PhD – Seer Medical; Udaya Seneviratne, MBBS, MD, PhD – St Vincent's Hospital, The University of Melbourne; Wendyl D'Souza, MBBS, MD, MPH, PhD – St Vincent's Hospital, The University of Melbourne
Rationale: Idiopathic generalised epilepsy (IGE) is not a benign condition with increasing evidence of enduring cognitive deficits beyond seizures. Emerging evidence also suggests a relationship between interictal discharge (IED) burden and seizure frequency. A closer understanding of this relationship can inform future therapeutic targets for cognitive outcomes and seizure control. We aimed to describe the temporal distribution, duration, and relationship to sleep using serial outpatient ambulatory 24-hour EEG recordings (aEEG) in juvenile absence epilepsy (JAE) and the relationship with antiepileptic drug (AED) adjustment._x000D_
Methods: We retrospectively identified 15 patients with JAE undergoing treatment adjustment with at least three aEEGs between 2012-2020. AED therapy was recorded at each serial aEEG. JAE was classified with onset of first or predominant absence seizures after age 9 years. We used a published automated detection algorithm to assist aEEG review and recorded the timing and length of IEDs. Following training, PH/AD independently marked IEDs with any uncertain or discordant IEDs resolved by WD. For each individual recording, the timing and length of the discharges was plotted against 24-hour clock._x000D_
Results: A total of 15 patients (onset age 9 to 16 years, median age at initial aEEG 21) were identified. In addition to absence, 13 (87%) had generalised tonic clonic seizures and 2 (13%) had myoclonic seizures. Across 45 aEEGs there was a total of 14701 IEDs (median 104; IQR 11 - 403). A total of 9917 (67.5%) IEDs occurred between 22:00 and 07:00 (individual aEEG median 63%; IQR 49.8% - 92.3%). IEDs show an overall pattern of clustered discharges during sleep compared to a more sporadic frequency in wakefulness. In addition, during sleep IEDs oscillate between high frequency peaks and quiescent periods throughout the night. There was a reduction in the proportion of patients with IEDs >3 seconds after AED adjustment from 9 (67%) to 4 (27%). After adjustment, all patients were treated with sodium valproate with 12 (80%) on combination therapy (40% at initial aEEG), most commonly lamotrigine (67%). Mean cumulative IED burden at final aEEG was 217.24 seconds (277.15 seconds at initial)._x000D_
Conclusions: JAE demonstrates a cyclical pattern in the distribution of IEDs with two-thirds occurring during sleep. Preliminary data suggests these may be modulated by AED adjustment. The oscillating pattern of IEDs during sleep has not been previously reported in humans and suggests coupling to a sleep phase generator, a critical time for memory encoding._x000D_
Funding: None
Neurophysiology