Abnormal heart rate variability during non-REM sleep and postictal generalized EEG suppression in focal epilepsy. (August 2022)

• Record Type: Journal Article
• Authors: Sakamoto, Mika; Jin, Kazutaka; Kitazawa, Yu; Kakisaka, Yosuke; Nakasato, Nobukazu
• Is Part Of: Clinical neurophysiology. Volume 140(2022)
• Page Start: 40
• Page End: 44
• Publication Date: 2022-08
• Subjects: Focal epilepsy -- Heart rate variability -- Non-REM sleep -- Postictal generalized EEG suppression -- Sudden unexpected death in epilepsy; ECG electrocardiography -- EMG electromyography -- FBTCS focal to bilateral tonic-clonic seizure -- HF high frequency -- HF nu normalized high frequency -- HRV heart rate variability -- LF low frequency -- LF nu normalized low frequency -- PGES postictal generalized EEG suppression -- SUDEP sudden unexpected death in epilepsy -- TCS tonic-clonic seizure -- VEM long-term video EEG monitoring -- VLF very low frequency; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2022.05.011
• Languages: English
• ISSNs: 1388-2457

Abstract

Highlights: Postictal generalized EEG suppression (PGES) + group showed abnormally decreased high frequency and increased low frequency heart rate variability (HRV) during non-REM sleep. Abnormally decreased parasympathetic activities during non-REM sleep are associated with PGES. Interictal HRV analysis during sleep may be useful to predict PGES, a potential biomarker of sudden unexpected death in epilepsy (SUDEP), without ictal recording. Abstract: Objective: To identify any relationship between abnormal interictal heart rate variability (HRV) during sleep and the occurrence of postictal generalized EEG suppression (PGES), a potential biomarker of sudden unexpected death in epilepsy (SUDEP), in patients with focal epilepsy. Methods: We retrospectively reviewed 34 consecutive patients with focal epilepsy, who presented with focal to bilateral tonic-clonic seizures (FBTCSs), 19 with PGES (PGES+) and 15 without PGES (PGES−), and 14 patients without epilepsy as controls. HRV spectrum analysis was performed for periods of 10 minutes during wakefulness, non-REM sleep, and REM sleep. HRV spectra consisted of high frequency (HF) and low frequency (LF) regions. Normalized HF representing parasympathetic activities and normalized LF were compared between the PGES+, PGES−, and control groups for each sleep stage. Results: The PGES+ group showed significantly decreased normalized HF and increased normalized LF during non-REM sleep compared to the PGES− ( P < 0.05) and control ( P < 0.01) groups, but not during wakefulness or REM sleep. Conclusions: Abnormal interictal HRV during non-REM sleep, indicating abnormally decreased parasympathetic activities, was associated with PGES in patients with FBTCS. Significance: This study proposes to further investigate the relation between decreased parasympathetic activities and PGES.