Electroencephalogram abnormalities in patients with NREM parasomnias

Electroencephalographic (EEG) changes in patients with NREM parasomnias (NRP) occur in sleep architecture as changes in slow wave sleep or cyclic pattern, which are not considered abnormal. However, abnormalities in EEG in these patients have recently been reported, indicating that EEG patterns in NRPs are not definitive. Moreover, most of the polysomnography (PSG) findings in NRP patients were reported in the adult population requiring data from pediatric population to avoid bias in conclusion.

In sum, 39 patients with a NRP were undergone comprehensive assessments including a PSG with additional EEG montages. EEG recordings were evaluated in patients without a history of epilepsy and further compared between pediatric and adult patients.

Twenty-three (59%) of the patients were pediatric and 77% were male. The mean age was 18.4 (±13.1) years. Of the patients, 19 (49%) had somnambulism, 13 (33%) had confusional arousal and seven (18%) had sleep terrors. Macrostructure of sleep detected by PSG was normal in all patients. After excluding 11 (28%) patients with a positive history of epilepsy, seven (25%) of 28 showed EEG abnormalities within K-complexes in NREM-II stage, six of whom were pediatric patients compared to only one adult (p < 0.05).

This study showed that patients with NRP may display EEG abnormalities in NREM-II stage. These abnormalities were more frequent in pediatric patients compared to adults. In NRP patients, utmost care should be taken in EEG evaluations to prevent false diagnosis of epilepsy.