Sleep structure in patients with psychogenic nonepileptic seizures.

Psychogenic nonepileptic seizures (PNES) are a significant public health problem, occurring in perhaps 25% of patients admitted to epilepsy monitoring units. Additional distinguishing characteristics for these patients would be helpful from both a clinical and a scientific standpoint. This study examines sleep structure by polysomnography in patients with PNES compared with patients with epileptic seizures (ES). ES and PNES were verified by video-EEG monitoring. All patients with PNES were evaluated by a psychiatrist. Eight female patients with PNES were compared with 10 female ES patients in the same age group. Percentage REM sleep was significantly greater for women with PNES (23+/-1%) than for those with ES (18+/-1%). There were no differences in other sleep stages, total sleep time, or sleep efficiency. REM latency was less in PNES patients although not significantly. The study suggests that patients with PNES have a sleep architecture similar to that found in major depression, known to be associated with increased REM sleep.