Rapid eye movement sleep reduction in patients with epilepsy: A systematic review and meta-analysis

Background: Compared to healthy controls, adults with epilepsy have a disrupted sleep architecture. Changes in sleep macrostructure may be associated with the refractoriness of epilepsy. However, there is no consensus regarding the changes in sleep architecture in patients with epilepsy. This meta-analysis aimed to elucidate the differences in sleep architecture between patients with epilepsy and healthy controls. Methods: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The PubMed, Embase, and Cochrane Central databases were searched (until May 2021) for studies comparing polysomnographic sleep macrostructures between patients with epilepsy and healthy controls. A meta-analysis was performed using a random-effects model. The percentage of rapid eye movement (REM) sleep, slow-wave sleep (SWS), and sleep efficiency (SE) were compared between patients with epilepsy and healthy controls. Results: Overall, 24 studies involving 789 patients with epilepsy and 599 healthy controls fulfilled the eligibility criteria. Compared to healthy controls, patients with focal epilepsy had decreased REM sleep and SE. Patients with generalised epilepsy had increased SWS and decreased SE. Subgroup analyses focussed on the potential effect of seizure control on sleep architecture. The results revealed that both antiseizure medication (ASM)-untreated and treated patients had decreased SE. ASM treatment may restore REM sleep in patients with generalised epilepsy but not in patients with focal epilepsy. Conclusions: This meta-analysis revealed statistically significant differences in the sleep macrostructure between patients with epilepsy and healthy controls. There were significant differences in the sleep macrostructure between ASM-untreated patients and healthy controls, which may be an intrinsic change attributable to epilepsy.