Electrophysiological Evaluation in Identifying Unique Sleep Features Among Anti-LGI1 Encephalitis Patients During Active and Recovery Phase

Xiaoyun Liu,1,* Liling Yang,1,* Yuxiang Han,1 Jingjing Xu,2 Zaiying Pang,1 Yifeng Du,1 Yabo Feng,1,* Youting Lin1,* 1Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan City, Shandong Province, 250021, People’s Republic of China; 2Department of Geriatrics, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan City, Shandong Province, 250021, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yabo Feng; Youting LinDepartment of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, No. 324, Jingwu Road, Huaiyin Zone, Jinan City, Shandong Province, 250021, People’s Republic of ChinaTel/Fax +86-531‐68776354Email fyb-sd@hotmail.com; youtinglin2019@126.comObjective: The purpose of this study was to illustrate the electrophysiological features of sleep disturbances in patients with anti-leucine-rich glioma-inactivated protein 1 (anti-LGI1) encephalitis in both active and recovery stages.Methods: Retrospectively filed video electroencephalogram (VEEG) and polysomnography (PSG) data in 24 patients with anti-LGI1 encephalitis were analyzed in comparison with that in 20 individuals without sleep disorders as control group.Results: Sleep efficiency (SE) and total sleep time involving REM and NREM sleep were significantly decreased in patients with anti-LGI1 encephalitis during the active stage compared to that during the recovery stage and in the control group. Imbalanced sleep structure was found, demonstrated by elevated N1, decreased N3 and REM components, as well as abnormal N2 structure characterized with significantly lower spindle duration and density during the active stage. These findings were independent of the presence of nocturnal episodic events or sleep hyperkinetic movements (HMs). HMs were present in 11/23 patients throughout NREM and REM sleep (nonspecific in sleep stages)