rTMS Improves Cognition in Patients With Self‐Limited Epilepsy With Centrotemporal Spikes With Electrical Status Epilepticus in Sleep via Increase of the Sleep Spindle

ABSTRACT Background Patients with self‐limited epilepsy with centrotemporal spikes (SeLECTS) and electrical status epilepticus in sleep (ESES) lead to cognitive impairment. However, therapeutic options are limited. Objectives The s leep spindle is a biomarker of cognitive dysfunction in patients with SeLECTS. This study aimed to explore whether the sleep spindle is linked to the outcome of repetitive transcranial magnetic stimulation (rTMS) in patients with SeLECTS with ESES. Methods Nine patients with SeLECTS with ESES underwent low‐frequency rTMS (≤ 1 Hz) or continuous theta burst stimulation (cTBS) for 10 days. To assess the clinical efficacy and alteration in the sleep spindle, EEG recordings were performed both before and after rTMS. A machine learning algorithm YASA was used to calculate the coupling of the sleep spindle and slow waves. Results 75% of patients remained seizure‐free for 6 months after rTMS. The spike–wave index (SWI) decreased significantly after rTMS compared with the baseline. The sleep spindle significantly increased in all patients at 3 months and 6 months after rTMS ( p = 0.002). Both IQ and MQ improved significantly at 6 months after rTMS. Improvement of IQ and increase of the sleep spindle was significantly positively correlated ( p = 0.035). The mean probability of the sleep spindle coupling in the slow wave “up” state increased from 28% to 55%. Conclusion(s) Increase of the sleep spindle and the mean probability of the sleep spindle coupling in the slow wave “up” state might be a potential mechanism for cognition improvement in patients with SeLECTS with ESES.