Brain changes in sleep-related hypermotor epilepsy observed from wakefulness and N2 sleep: A matched case-control study.

OBJECTIVE

Sleep-related hypermotor epilepsy (SHE) is a relatively uncommon epilepsy syndrome, characterized by seizures closely related to the sleep cycle. This study aims to explore interictal electroencephalographic (EEG) characteristics in SHE.

METHODS

We compared EEG data from 20 patients with SHE, 20 patients with focal epilepsy (FE), and 14 healthy controls, carefully matched for age, sex, education level, epilepsy duration, and drug-resistant epilepsy.

RESULTS

Our findings revealed distinct patterns of power spectral density in SHE patients during wakefulness and N2 sleep compared to other groups, suggesting potential diagnostic value. During wakefulness, SHE patients showed enhanced frontal lobe power across all frequency bands, but decreased frontal lobe power in low-frequency bands during N2 sleep. Additionally, a positive correlation was found between frontal γ band power and epilepsy duration in SHE patients during N2 sleep but not during wakefulness.

CONCLUSIONS

These findings suggest that interictal EEG abnormalities during wakefulness and N2 sleep might be used as potential biomarkers for the diagnosis of SHE.

SIGNIFICANCE: This study is the first to simultaneously characterize EEG during sleep and wakefulness in SHE patients during interictal periods, with potential utility for diagnosis.