Nature and Science of Sleep (Oct 2018)
Sleep-related hypermotor epilepsy: prevalence, impact and management strategies
Abstract
Veronica Menghi,1 Francesca Bisulli,2 Paolo Tinuper,2 Lino Nobili3,4 1Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy; 2IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; 3“Claudio Munari” Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy; 4Department of Neuroscience (DINOGMI), IRCCS, Giannina Gaslini Institute, University of Genoa, Genoa, Italy Abstract: Sleep-related hypermotor epilepsy (SHE), previously called nocturnal frontal lobe epilepsy (NFLE), is a focal epilepsy characterized by asymmetric tonic/dystonic posturing and/or complex hyperkinetic seizures occurring mostly during sleep. SHE fulfills the definition of rare disease with an estimated minimum prevalence of 1.8/100,000 individuals, and it represents about 10% of drug-resistant surgical cases. Although SHE and autosomal-dominant SHE (ADSHE) have been considered benign epileptic conditions for a long time, emerging data have shed light on the severity of this disorder and some peculiar features can impact negatively on the quality of life of SHE patients. In fact, seizure frequency can be very high, resulting in nocturnal sleep fragmentation with possible diurnal consequences such as excessive sleepiness and fatigue. Moreover, recent studies, adopting a systematic neuropsychological assessment, have shown deficits in memory, executive functions and visuo-spatial abilities in almost half of SHE patients. Intellectual disabilities and psychiatric disorders have also been reported in some genetic forms. SHE may also exert a negative effect on health-related quality of life, especially in domains pertaining to a patient’s role in the family, social context and patient’s illness experience. Despite a good response to pharmacological treatment, especially with carbamazepine, 30% of SHE patients suffer from drug-resistant seizures. Finally, recent studies suggest a poor prognosis in a high percentage of SHE patients with a 20.4% cumulative probability of achieving terminal remission at 10 years from onset. For selected drug-resistant SHE patients, epilepsy surgery is the only treatment offering high probability of recovery, both for seizures and for epilepsy-related sleep alterations. Keywords: epilepsy, parasomnias, sleep-related hypermotor epilepsy, nocturnal frontal lobe epilepsy, epidemiology
