Analysis of the first night effect and sleep parameters in medically refractory epilepsy patients

Abstract

Objectives To assess the first night effect (FNE) and compare sleep stage proportions to normative values in a sample of medically refractory epilepsy patients. Patients and methods Sleep parameters of 53 epilepsy patients, ages (18–56, mean: 34±12, 25 females 28 men), who underwent two consecutive nights of polysomnography (PSG) were compared. Non-rapid eye movement (NREM) stage 3 and NREM stage 4 were combined as slow wave sleep (SWS). Sleep efficiency, sleep latency, rapid eye movement (REM) latency, number of stage shifts, total minutes and proportion of total sleep time for stage 1, stage 2, SWS, and REM sleep were compared between the 2 nights. Results SWS was the only parameter that differed between nights 1 and 2 for both total minutes ( P=0.02) and proportion of total sleep time ( P=0.01), although the means for both nights were within the normative range. Comparing sleep proportions to normative values indicates that our patients had increased NREM stage 1 and decreased REM sleep. Conclusions We observed a minimal FNE in this sample of epilepsy patients manifested by reduced SWS. Multiple PSGs to accommodate the FNE may not be necessary in this population.