Multi-day rhythms modulate seizure risk in epilepsy

Abstract

Epilepsy is defined by the seemingly random occurrence of spontaneous seizures. The ability to anticipate seizures would enable preventative treatment strategies. A central but unresolved question concerns the relationship of seizure timing to fluctuating rates of interictal epileptiform discharges (here termed interictal epileptiform activity, IEA), a marker of brain irritability observed between seizures by electroencephalography (EEG). Here, in 37 subjects with an implanted brain stimulation device that detects IEA and seizures over years, we find that IEA oscillates with circadian and subject-specific multidien (multi-day) periods. Multidien periodicities, most commonly 20–30 days in duration, are robust and relatively stable for up to 10 years in men and women. We show that seizures occur preferentially during the rising phase of multidien IEA rhythms. Combining phase information from circadian and multidien IEA rhythms provides a novel biomarker for determining relative seizure risk with a large effect size in most subjects.

Ultra‐long‐term subcutaneous home monitoring of epilepsy—490 days of EEG from nine patients

“…This is well in line with the findings published by Baud et al 17 Qualitatively, the objective seizure count provided information on participants' response to changes in AEDs that would not have been revealed from the seizure diaries. We have shown that home monitoring for approximately 3 months is feasible ID Onset zone Semiology a without major adverse events or significant impact on activities of daily living.…”

“…Several other seizure-detection devices have appeared within the last decade, some employing EEG 2,10,17,21,22 and some employing other technologies, such as EMG/accelerometry, 23,24 heart rate variability, 25 electrodermal activity, or a combination of these. Several other seizure-detection devices have appeared within the last decade, some employing EEG 2,10,17,21,22 and some employing other technologies, such as EMG/accelerometry, 23,24 heart rate variability, 25 electrodermal activity, or a combination of these.…”

Layer‐ and Cell‐Specific Recruitment Dynamics during Epileptic Seizures In Vivo

“…First, EEG and ECoG recordings show that many partial and generalized seizures initiate with a single or recurrent spikes . Second, long‐term recordings reveal the frequency of interictal spikes tend to gradually increase prior to seizures . Third, single cell intracellular voltage recordings show that paroxysmal depolarization shifts underlie both spikes and onset of seizures .…”

Ensembling crowdsourced seizure prediction algorithms using long‐term human intracranial EEG

“…Moreover, algorithms that directly account for known seizure triggers, such as sleep‐wake rhythms, as well as novel measurement approaches may offer alternative routes to performance gains . In addition, recent work looking at long‐term rhythms holds significant promise for seizure forecasting, could be applied in the machine learning context, and suggests that the performance limits seen here may not be tied to potential limits imposed by the physiologic processes underlying seizure occurrence.…”