Non-rapid eye movement sleep characteristics in idiopathic REM sleep behavior disorder

This study investigated slow waves (SW; > 75 μV and < 4 Hz) characteristics in patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD). Thirty patients with iRBD and 30 age- and sex-matched healthy subjects underwent one polysomnographic (PSG) nocturnal sleep recording. SW automatic detection was performed on F3, C3, P3, and O1 leads and SW characteristics were derived (SW density, amplitude, frequency, slope, and duration of negative and positive phases). We also compared iRBD patients and control subjects on PSG variables and delta (0.25-4.0 Hz) spectral power. No between-group differences were found on PSG variables, delta spectral power, or SW characteristics. Results show no SW abnormalities in iRBD patients compared to healthy participants, which suggests similar level of synchronization of thalamo-cortical neurons during N-REM sleep.