Seizure triggers identified postictally using a smart watch reporting system.

Persons with epilepsy (PWE) often report that seizure triggers can influence the occurrence and timing of seizures. Some previous studies of seizure triggers have relied on retrospective daily seizure diaries or surveys pertaining to all past seizures, recent and/or remote, in respondents. To assess the characteristics of seizure triggers at the granularity of individual seizures, we used a seizure-tracking app, called EpiWatch, on a smart watch system (Apple Watch and iPhone) in a national study of PWE. Participants tracked seizures during a 16-month study period using the EpiWatch app. Seizure tracking was initiated during a pre-ictal state or as the seizure was occurring and included collection of biosensor data, responsiveness testing, and completion of an immediate post-seizure survey. The survey evaluated seizure types, auras or warning symptoms, loss of awareness, use of rescue medication, and seizure triggers for each tracked seizure. Two hundred and thirty four participants tracked 2493 seizures. Ninety six participants reported triggers in 650 seizures: stress (65.8%), lack of sleep (30.5%), menstrual cycle (19.7%), and overexertion (18%) were the most common. Participants often reported having multiple combined triggers, frequent stress with lack of sleep, overexertion, or menses. Participants who reported triggers were more likely to be taking 3 or more anti-seizure medications compared to participants who did not report triggers. Participants were able to interact with the app and use mobile technology in this national study to record seizures and report common seizure triggers. These findings demonstrate the promise of longitudinal, self-reported data to improve our understanding of epilepsy and its related comorbidities.

Postictal stertor: Associations with focal and bilateral seizure types.

OBJECTIVE: The objective of the present study was to determine the association between respiratory stertor and focal and bilateral seizure types. METHODS: We characterized ictal and postictal behaviors during symmetric bilateral tonic-clonic (TC) and asymmetric TC seizures in the Johns Hopkins University (JHU) epilepsy monitoring unit, comparing these to focal unaware seizures. We measured the presence and duration of postictal stertorous respirations, postictal generalized electroencephalographic suppression (PGES), immobility/motor dysfunction, and encephalopathy and determined their associations and relationship to seizure types. RESULTS: In initial seizures recorded in 80 consecutive patients, bilateral symmetric TC seizures (N = 35) were strongly associated with PGES (97%, p < 0.001) and postictal stertorous respirations (89%, p < 0.001). Only 10% of the 20 patients with asymmetric TC seizures had brief PGES; focal unaware seizures (N = 25) were not associated with PGES or stertorous breathing. Some patients (24%) with asymmetric or bilateral symmetric TC seizures had severe postictal encephalopathy with stertor that was separate or extended beyond periods of PGES. CONCLUSION: Bilateral symmetric TC seizures, but not focal unaware seizures, have postictal stertor during PGES. Severe postictal encephalopathy, however, is also associated with motor dysfunction and stertor. Stertor appears to be a compensatory postictal respiratory pattern for ictal/postictal hypoxemia and occurs with PGES or postictal encephalopathy.

Strategies for non-EEG seizure detection and timing for alerting and interventions with tonic-clonic seizures.

Sudden unexpected death in epilepsy (SUDEP) is a common cause of death in epilepsy and frequently occurs following generalized tonic-clonic seizures (GTCS). Non-electroencephalography (EEG) seizure detection systems using mobile sensor devices permit caregivers to assist patients during seizures and may reduce risks for complications of seizures such as injuries and SUDEP. We review changes in accelerometry, electrodermal activity, and heart rate associated with tonic-clonic seizures and their use in detection systems, including multimodal detectors. We reviewed current and past publications reporting data on linkage between GTCS, post-ictal generalized EEG suppression (PGES), and ventilatory dysfunction. The timing and duration of postictal immobility and respiratory dysfunction associated with convulsions help identify which patients might benefit the most from seizure monitoring and from benchmarks for the timing of seizure detection, caregiver alerting, and interventions.