Abstracts

Rationale: Epilepsy can have a direct impact on sleep: nocturnal seizures may interrupt sleep and may thus impair sleep architecture and conversely, sleep can influence epileptic seizures. On the one hand, sleep disorders (daytime sleepiness, insomnia, obstructive sleep apnea, etc.) are frequent in epilepsy and are one of the factors that can also influence the quality of life of patients with epilepsy. Furthermore, all antiepileptic drugs (AEDs) may have effects on the sleep architecture and daytime sleepiness. On the other hand, an important reduction of REM sleep linked to cognitive functions has been described in certain types of epilepsy.The objective of the study is to describe the characteristics of sleep (quality of sleep, daytime sleepiness) in patients with epilepsy and to see the impact that these have on the patients' quality of life and the possible relationship with the presence of cognitive impairment. Methods: Observational, retrospective, cross-sectional, multicenter study conducted in 15 Spanish centers. The study was approved by IRB and written consent was obtained for each patient. Population: patients of any gender, aged 12 or older diagnosed with focal or generalized epilepsy, in treatment with at least one antiepileptic drug and without any diagnosed sleep disorders. The sleep characteristics will be measured by the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS); patients' Quality of life will be measured by the QOLIE-10 Questionnaire and cognitive impairment by the Montreal Cognitive assessment Test (MoCa Test).  Results: Currently a total of 52 patients have been recruited (34.7% of the theoretical sample). Of these, 53.8% are women with a mean age of 44.6 years (SD=16.01). Among these patients, 25% have a family history of epilepsy, 76.9% have focal type epilepsy (44.2% have structural epilepsy with hippocampal sclerosis as the main cause in 39% of the cases) and 38.5% have unknown epilepsy type. The mean seizure frequency in the 30 patients that reported seizures during the year previous to the assessment was 1.13 (SD=0.43) per patient. The types of epileptic seizures were 76.5% focal and 17.6% generalized. The AEDs most currently actively used were levetiracetam (38.5%), eslicarbazepine acetate (25%) and lacosamide (19.2%).The impact of sleep quality on the patients' QoL (figure 1a) showed a significant correlation of 38.7% (p-value = 0,011); the correlation had a greater magnitude (66.2%, p-value=0,000) if we focused on the patients' daytime dysfunction. However, sleep quality did not show a significant impact (p-value=0.432) on cognitive impairment.Regarding the impact of daytime sleepiness on the patients' QoL (figure 1b) is significant both at the total score (p-value 0.021) as well as on the questionnaire domains role functioning (p-value 0.031) and the patients' mental health (p-value 0.029). However, this was not the case with regards to cognitive impairment (p-value 0.866). Conclusions: Sleep quality and daytime sleepiness have a significant relationship with the QoL of patients with epilepsy. However, they do not show any relationship with patients' cognitive impairment in this preliminary analysis.  Funding: Study support was provided by ESTEVE Pharmaceutical SA and EISAI Ltd.