Hypnopompic seizures

Abstract

The relationship between epilepsy and sleep is complex and bidirectional. Ictal awakening is probably a common and well-described phenomenon. In this small observational study we describe arousal from sleep as the only, or at least main, manifestation of some epileptic seizures. We coin the term "hypnopompic seizures" to describe this entity. Five patients with intractable epilepsy were monitored by continuous video-electroencephalogram. Four of them had left temporal lobe epilepsy and one patient had generalised epilepsy. Hypnopompic seizures accounted for 30-100% of their seizure types captured during monitoring. All the seizures occurred during stage II sleep and were brief. Hypnopompic seizures are extremely subtle and may be underdiagnosed and underreported. Future larger studies are needed to shed some light on this unique entity and its neuropathophysiology. Epileptologists should be aware of this type of seizure and careful review of electroencephalograms during the transition from sleep to arousal is imperative to capture these seizures. Physicians, patients and families also need to be aware of such a subtle manifestation of seizures. Improved awareness of hypnopompic seizures and subtle seizures, in general, help guide accurate and early diagnosis, thorough monitoring and appropriate management.