Sleep and Epilepsy

Network alterations in temporal lobe epilepsy during non-rapid eye movement sleep and wakefulness

OBJECTIVE

Investigate sleep and temporal lobe epilepsy (TLE) effects on brain networks derived from electroencephalography (EEG).

METHODS

High-density EEG was recorded during non-rapid eye movement (NREM) sleep stage 2 (N2) and wakefulness in 23 patients and healthy controls (HC). Epochs without epileptic discharges were source-reconstructed in 72 brain regions and connectivity was estimated. We calculated network integration and segregation at global (global efficiency, GE; average clustering coefficient, avgCC) and hemispheric level. These were compared between groups across frequency bands and correlated with the individual proportion of wakefulness- or sleep-related seizures.

RESULTS

At the global level, patients had higher delta GE, delta avgCC and theta avgCC than controls, irrespective of the vigilance state. During wakefulness, theta GE of patients was higher than controls and, for patients, theta GE during wakefulness was higher than during N2. Wake-to-sleep differences in TLE were notable only in the ipsilateral hemisphere. Only measures from wakefulness recordings correlated with the proportion of wakefulness- or sleep-related seizures.

CONCLUSIONS

TLE network alterations are more prominent during wakefulness and at lower frequencies. Increased integration and segregation suggest a pathological 'small world' configuration with a possible inhibitory role.

SIGNIFICANCE

Network alterations in TLE occur and are easier to detect during wakefulness.

The mediating role of social support in the relationship between psychosocial problems and sleep patterns of adolescents with epilepsy

AIM

This study was conducted to examine the mediating role of social support in the relationship between psychosocial problems of adolescents with epilepsy and their sleep patterns.

METHODS

The data were collected with Adolescent Information Form, Strength and Difficulties Questionnaire, Sleep Disturbance Scale for Children and Multidimensional Scale of Perceived Social Support in this descriptive and correlational study. The mediating role of multidimensional social support that children with epilepsy received with the Process Macro program was examined in the relationship between their psychosocial problems and their sleep status. Process model 4 was used and analysis was made based on the Bootstrap method.

RESULTS

As a result of the analysis, it was found that the participants had been diagnosed with epilepsy for a mean of 6.0 ± 1.61 years and had a mean of 3.1 ± 2.48 seizures per week. It was found that the sleep problems experienced by adolescents with epilepsy affected their psychosocial health and this effect was at the level of 84 % (β = 0.933; p < 0.001). The effect of perceived social support on the dependent variable sleep disturbance in adolescents with epilepsy was found to be statistically significant (β = -0.540; p < 0.001). It was determined that the Psychosocial Health Status score of adolescents diagnosed with epilepsy explained 87 % of the change in sleep disturbance experienced with perceived social support (p < 0.001). The effect of social support perceived by adolescents with epilepsy on sleep disturbance was found to be statistically significant. Perceived social support has no effect on the psychosocial problems they experience.

CONCLUSIONS

It was found that social support was not a mediator in the relationship between psychosocial problems of adolescents with epilepsy and their sleep status.

A polysomnographic study of slow-wave sleep loss in elderly patients with epilepsy

Objective

The primary objective is to explore what causes slow-wave sleep loss in elderly patients with epilepsy. The secondary objective is to identify the PSG characteristics in elderly patients with epilepsy. The clinical demographics, sleep architecture, sleep-related events, and interictal epileptiform discharges are to be evaluated in the objectives.

Methods

The video electroencephalography (VEEG) and polysomnogram (PSG) data from 44 elderly patients with epilepsy and 52 elderly patients with sleep disorders but without definite central nervous system diseases were analysed. This was a case-control study. The differences in the PSG sleep architecture parameters (total sleep time (TST), sleep efficiency, wake after sleep onset, etc.) and sleep-related events (apnea hypopnea index, oxygen desaturation index (ODI), periodic limb movement index, etc.) between the epilepsy and control groups. As Additionally, these parameters were assessed within the elderly patients with epilepsy, comparing the slow-wave sleep existence and slow-wave sleep loss groups, using VEEG and PSG.

Results

The epileptic group exhibited significantly lower TST (343.477 ± 96.3046min vs 389.115 ± 61.5727min, p < 0.05), rapid eye movement (%) (13.011 ± 7.5384 vs 16.992 ± 6.7025, p < 0.05), non-rapid eye movement stage 3 (%) (1.35[0,7.225] vs 3.65[0.425,13.75], p < 0.05), and sleep efficiency (%) (69.482 ± 14.1771% vs 77.242 ± 10.6171%, p < 0.05). Conversely, the ODI (25.6[9.825,51.775] events/hour vs 16.85[5.3,30.425] events/hour, p < 0.05) and spontaneous arousal index (4.0455[2.1805,6.9609] events/hour vs 2.9709[1.4747,5.0554] events/hour, p < 0.05) were significantly higher in elderly patients with epilepsy. The prevalence of obstructive sleep apnea-hypopnea syndrome (OSAHS) was significantly higher in the slow-wave sleep loss group than in the slow-wave sleep existence group (100% vs 77.8%, p < 0.05). The incidence of slow-wave sleep loss was lower in patients with epilepsy aged between 75 and 85 years compared to those aged between 65 and 75 years.

Conclusion

Elderly patients with epilepsy exhibit higher levels of ODI and spontaneous arousal index. Our findings indicate that OSAHS could be a contributing factor to slow-wave sleep loss in this population. The incidence of slow-wave sleep loss was lower in patients aged above 75 years among elderly patients with epilepsy.

The impact of epilepsy and antiseizure medications on sleep: Findings from a large European survey in adults with epilepsy and matched controls

OBJECTIVE

To assess the impact of epilepsy and antiseizure medications (ASMs) on sleep quality in people with epilepsy (PWE).

METHODS

An online survey was conducted in France, Germany, Italy, Spain and the UK among PWE taking >1 ASM and matched controls. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). Associations between sleep quality (global PSQI) and overall quality of life (QoL; assessed using the 12-Item Short Form Survey [SF-12]) and sleep quality and depressive symptoms (assessed using the Neurological Disorders Depression Inventory for Epilepsy [NDDI-E]) were also evaluated.

RESULTS

Overall, 500 PWE and 500 matched controls were included. PWE had significantly greater mean global PSQI scores than controls (9.32 vs 7.56; p < 0.0001), with 80% reporting a score >5 versus 66% of controls (p < 0.001). PWE experienced significantly more problems with most PSQI components than controls. Mean global PSQI scores in PWE receiving 2 versus ≥3 ASMs were 9.03 and 10.18, respectively (p < 0.004); global PSQI scores >5 were reported in 76% versus 90%, respectively (p = 0.001). Regimens containing lamotrigine or phenobarbital were associated with poorer sleep quality than those without these ASMs. In PWE, negative correlations were identified between global PSQI scores and both the SF-12 physical and mental components (Pearson's correlation coefficient [PCC], -0.61 and -0.40, respectively); NDDI-E and global PSQI scores were positively correlated (PCC, 0.6).

CONCLUSIONS

PWE experience significantly worse sleep quality than people without epilepsy, with some ASMs contributing to poorer sleep. QoL and physical and mental health were all affected by sleep quality in PWE.

Analogous cortical reorganization accompanies entry into states of reduced consciousness during anesthesia and sleep

Theories of consciousness suggest that brain mechanisms underlying transitions into and out of unconsciousness are conserved no matter the context or precipitating conditions. We compared signatures of these mechanisms using intracranial electroencephalography in neurosurgical patients during propofol anesthesia and overnight sleep and found strikingly similar reorganization of human cortical networks. We computed the "effective dimensionality" of the normalized resting state functional connectivity matrix to quantify network complexity. Effective dimensionality decreased during stages of reduced consciousness (anesthesia unresponsiveness, N2 and N3 sleep). These changes were not region-specific, suggesting global network reorganization. When connectivity data were embedded into a low-dimensional space in which proximity represents functional similarity, we observed greater distances between brain regions during stages of reduced consciousness, and individual recording sites became closer to their nearest neighbors. These changes corresponded to decreased differentiation and functional integration and correlated with decreases in effective dimensionality. This network reorganization constitutes a neural signature of states of reduced consciousness that is common to anesthesia and sleep. These results establish a framework for understanding the neural correlates of consciousness and for practical evaluation of loss and recovery of consciousness.

Biological rhythms and epilepsy treatment

Approximately one-third of patients with epilepsy are drug-refractory, necessitating novel treatment approaches. Chronopharmacology, which adjusts pharmacological treatment to physiological variations in seizure susceptibility and drug responsiveness, offers a promising strategy to enhance efficacy and tolerance. This narrative review provides an overview of the biological foundations for rhythms in seizure activity, clinical implications of seizure patterns through case reports, and the potential of chronopharmacological strategies to improve treatment. Biological rhythms, including circadian and infradian rhythms, play an important role in epilepsy. Understanding seizure patterns may help individualize treatment decisions and optimize therapeutic outcomes. Altering drug concentrations based on seizure risk periods, adjusting administration times, and exploring hormone therapy are potential strategies. Large-scale randomized controlled trials are needed to evaluate the efficacy and safety of differential and intermittent treatment approaches. By tailoring treatment to individual seizure patterns and pharmacological properties, chronopharmacology offers a personalized approach to improve outcomes in patients with epilepsy.

Effect of Epilepsy on Sleep Quality During Pregnancy and Postpartum

BACKGROUND AND OBJECTIVES

This study seeks to understand how sleep is affected in pregnant women with epilepsy (WWE) relative to healthy pregnant women during pregnancy and postpartum and to nonpregnant WWE during comparative periods. Sleep affects maternal health and mood during pregnancy. Maternal sleep disturbances are related to poor fetal growth and increased fetal deaths. Epilepsy is the most common neurologic condition in pregnancy. Sleep disruption can worsen epileptic seizures. The interplay between epilepsy, pregnancy, and sleep is poorly understood.

METHODS

The Maternal Outcomes and Neurodevelopmental Effects of Antiepileptic Drugs (MONEAD) study is an NIH-funded, prospective, observational, multicenter study, enrolling women from December 2012 through January 2016. Sleep quality was assessed using the average Pittsburgh Sleep Quality Index collected during pregnancy, postpartum, or analogous periods. Sleep scores range from 0 to 21 with higher scores indicating worse sleep quality; scores >5 are associated with poor sleep quality.

RESULTS

Of 351 pregnant WWE, 105 healthy pregnant women, and 109 nonpregnant WWE enrolled in the MONEAD study, data from 241 pregnant WWE, 74 healthy pregnant women, and 84 nonpregnant WWE were analyzed. Pregnant WWE had worse sleep (a higher mean sleep score) during pregnancy compared with healthy pregnant women in unadjusted analysis (p = 0.006), but no longer significant in adjusted analysis (p = 0.062); pregnant WWE (least square mean sleep score [95% CI] = 5.8 [5.5-6.1]) vs healthy pregnant women (5.1 [4.6-5.7]). During postpartum period, WWE (5.6 [5.4-5.9]) had similarly impaired sleep compared with healthy women (5.7 [5.2-6.2]; adjusted p = 0.838). Sleep was significantly worse in pregnant WWE vs nonpregnant WWE (for comparable period) in pregnancy and postpartum in unadjusted and adjusted analyses; adjusted scores for pregnant WWE in pregnancy (5.7 [5.4-6.0]) and those in postpartum (5.7 [5.4-6.0]) compared with those for nonpregnant WWE (4.7 [4.2-5.3]; p = 0.002) and (4.1 [3.6-4.7]; p < 0.001), respectively. Sleep quality between pregnancy and postpartum varied only in healthy pregnant women (change in mean score = 0.8 [0.2-1.3]; p = 0.01), whose sleep was worse in postpartum.

DISCUSSION

Pregnant WWE had worse sleep during pregnancy and postpartum period than nonpregnant WWE during comparable periods in the adjusted analysis.

TRIAL REGISTRATION INFORMATION

The study is registered at ClinicalTrials.gov as NCT01730170.

Drug-Induced Insomnia and Excessive Sleepiness

Undesirable side effects of insomnia and/or sleepiness may occur with many prescribed drugs, psychotropics as well as non-psychotropics. These central nervous system effects can be explained by the interactions of the drug with any of the numerous neurotransmitters and receptors that are involved in sleep and wakefulness. Also a close - sometimes bidirectional - relationship between disease and (disturbed) sleep/wakefulness is often present e.g. in chronic pain; drug effects may lead this vicious circle in both ways. Besides the importance for health and quality of life, effects on sleep or waking function can be a potential source of non-compliance.

Changes in Pre- and Postsurgery for Drug Resistant Epilepsy: Cognition and Sleep

BACKGROUND

Most patients with drug-resistant epilepsy (DRE) have cognitive impairment and sleep disturbance. There was a significant correlation between sleep disorders and cognitive dysfunction. This study performed surgical treatment on patients with DRE and observed seizures, sleep, and cognition in patients with DRE in 6th month after operation to clarify the correlation between sleep and cognition in DRE patients.

METHODS

21 individuals with DRE were recruited to enroll in this trial. Each participant completed epileptic focus resection. Seizure frequency was the principle index; the mean seizure frequency was 1 month before surgery and six months after surgery. Cognitive function was assessed by MMSE, and sleep status was assessed by PSQI and ActiGraph; assessments were performed before and 6 months after surgery.

RESULTS

There were significant differences between conditions on all outcome measures; after 6 months of surgery, compared with before treatment, the monthly average seizure frequency of DRE decreased, which was statistically significant (P < 0.001) compared with that before treatment. The MMSE score of DRE patients was significantly higher than before (P < 0.01), especially the ability of attention, calculation, and recall in MMSE score, which was significantly higher than before operation (respectively, P < 0.001 and P < 0.01). The subjective sleep evaluation index PSQI and objective measurement of sleep latency, total sleep time, and sleep efficiency of patients with DRE by ActiGraph were statistically significant (respectively, P < 0.01) compared with that before treatment. There was a correlation between seizure frequency and MMSE (r = -0.8887, P < 0.0001), PSQI (0.5515, P < 0.01), sleep latency (0.5353, P < 0.05), total sleep time (-0.7814, P < 0.0001), and sleep efficiency (-0.4380, P < 0.05).

CONCLUSIONS

Surgery can effectively reduce the epileptic seizures frequency in patients with DRE and indirectly improve the computational power, attention, recall ability, and sleep status of patients. However, this result did not show a correlation between improved cognitive function and sleep, so the patient's cognitive function may be caused by surgery to improve the frequency of seizures. So, whether the improvement of patients' sleep conditions can also significantly improve the frequency of attacks and cognitive function in patients with DRE needs further exploration.

Delivering epilepsy care in low-resource settings: the role of technology

INTRODUCTION

The implementation of technology in the field of epileptology has traditionally focused on its use for diagnosis and treatment and has, unsurprisingly, been capital-intensive, making it therefore mainly implementable in advanced high-income countries. Because of technological innovations over the past 20 years there has been almost a paradigm shift, particularly in access to and the potential for implementing relevant technology in lesser developed environments. Nearly 80% of people living with epilepsy live in low and middle-income countries.

AREAS COVERED

The challenge and the purpose of this paper is to discuss how technology can be implemented into lesser-resourced contexts not only cost-effectively but in a cost-saving way while also building capacity and thus sustainability.

EXPERT OPINION

The rate of technological advancement presents the risk of progressive widening of the technology and care gaps between advanced and lesser developed regions. Implementing technology is both about finding relevant appropriate technologies for the individual contexts of a diverse range of countries but also about repurposing low-tech technologies for application in epilepsy care in these areas. Finally exciting advances such as autonomous driving, digital twinning and robotic surgery will likely transform epilepsy care in several lower-resourced settings in the next 5-10 years.

Electroencephalographic assessment of infant spinal anesthesia: A pilot prospective observational study

INTRODUCTION

Spinal anesthesia is utilized as an alternative to general anesthesia in infants for some surgeries. After spinal anesthesia, infants often become less conscious without administration of sedative medications. The aim of this study was to assess electroencephalographic (EEG) correlates after spinal anesthesia in a cohort of infants.

PATIENTS AND METHODS

This pilot study included 12 infants who underwent spinal anesthesia. Unprocessed electroencephalography was recorded. The electroencephalogram was interpreted by four neurologists. Processed analyses compared electroencephalogram changes 30 min after spinal anesthesia to baseline.

RESULTS

Following spinal anesthesia, all 12 infants became sedated. Electroencephalography in all 12 demonstrated Stage 2 sleep with the appearance of sleep spindles (12-14 Hz) in the frontal and central leads in 8/12 (67%) of subjects. The median time to onset of sleep spindles was 24.7 interquartile range (21.2, 29.9) min. The duration of sleep spindles was 25.1 interquartile range (5.8, 99.8) min. Voltage attenuation and background slowing were the most common initial changes. Compared to baseline, the electroencephalogram 30 min after spinal anesthesia showed significantly increased absolute delta power (p = 0.02) and gamma power (p < 0.0001); decreases in beta (p = 0.0006) and higher beta (p < 0.0001) were also observed. The Fast Fourier Transform power ratio difference for delta/beta was increased (p = 0.03). Increased coherence was noted in the delta (p = 0.02) and theta (p = 0.04) bandwidths.

DISCUSSION

Spinal anesthesia in infants is associated with increased electroencephalographic slow wave activity and decreased beta activity compared to the awake state, with appearance of sleep spindles suggestive of normal sleep. The etiology and significance of the observed voltage attenuation and background slowing remains unclear.

CONCLUSIONS

The EEG signature of infant spinal anesthesia is distinct from that seen with general anesthesia and is consistent with normal sleep. Further investigation is required to better understand the etiology of these findings. Our preliminary findings contribute to the understanding of the brain effects of spinal anesthesia in early development.

Characterization of Seizure Induction Methods in Drosophila

Epilepsy is one of the most common neurologic disorders. Around one third of patients do not respond to current medications. This lack of treatment indicates a need for better understanding of the underlying mechanisms and, importantly, the identification of novel targets for drug manipulation. The fruit fly Drosophila melanogaster has a fast reproduction time, powerful genetics, and facilitates large sample sizes, making it a strong model of seizure mechanisms. To better understand behavioral and physiological phenotypes across major fly seizure genotypes we systematically measured seizure severity and secondary behavioral phenotypes at both the larval and adult stage. Comparison of several seizure-induction methods; specifically electrical, mechanical and heat induction, show that larval electroshock is the most effective at inducing seizures across a wide range of seizure-prone mutants tested. Locomotion in adults and larvae was found to be non-predictive of seizure susceptibility. Recording activity in identified larval motor neurons revealed variations in action potential (AP) patterns, across different genotypes, but these patterns did not correlate with seizure susceptibility. To conclude, while there is wide variation in mechanical induction, heat induction, and secondary phenotypes, electroshock is the most consistent method of seizure induction across known major seizure genotypes in Drosophila.

Quantitative evaluation of the microstructure of rapid eye movement sleep in refractory epilepsy: a preliminary study using electroencephalography and heart rate variability analysis

INTRODUCTION

Patients with epilepsy have a disturbed sleep architecture. Polysomnographic studies have shown that patients with refractory epilepsy have decreased rapid eye movement (REM) sleep and longer REM latency than those with medically controlled epilepsy. However, little is known about the differences in the REM sleep microstructure between these patient groups.

METHODS

We conducted a retrospective case-control study of 20 patients with refractory epilepsy (refractory group) and 28 patients with medically controlled epilepsy (medically controlled group). All patients completed sleep questionnaires and underwent overnight in-lab polysomnography. Five-minute electroencephalogram recordings at the C3 and C4 electrodes from each REM sleep were selected for spectral analysis, and 5-min electrocardiogram segments recorded during REM sleep were used for heart rate variability analysis. The groups' scores on the sleep questionnaires, polysomnographic sleep parameters, indices of sleep-related breathing disorders, and REM sleep electroencephalogram spectra were compared.

RESULTS

The refractory group had decreased REM sleep (p < 0.001) and longer REM latency (p = 0.0357) than those of the medically controlled group. Moreover, electroencephalogram spectral analysis revealed that the refractory group had decreased absolute beta power (p = 0.0039) and relative beta power (p = 0.0035) as well as increased relative delta power (p = 0.0015) compared with the medically controlled group.

CONCLUSIONS

Differences in the polysomnographic macrostructure and REM sleep microstructure between the study groups suggest REM sleep dysregulation in patients with refractory epilepsy.

Development and Evaluation of the CASTLE Trial Online Sleep Intervention for Parents of Children with Epilepsy

Introduction: Many of the sleep problems experienced by children with epilepsy (CWE) have the same behavioural basis as common sleep problems seen in typically developing (TD) children. Behavioural sleep interventions (BSIs) are widely used to treat these sleep problems in TD children and are hypothesised to be effective for CWE. However, specific considerations need to be addressed and incorporated into a BSI for CWE to ensure the intervention is tailored to this population's needs. This paper details developing and tailoring an online BSI for parents of CWE, to be used in the CASTLE (Changing Agendas on Sleep, Treatment and Learning in Epilepsy) Sleep-E clinical trial. Method: In phase one, two existing theory-driven paediatric BSIs were adapted into a novel online behavioural sleep intervention (CASTLE Online Sleep Intervention or COSI) which specifically incorporated the needs and requirements reported by nine parents of CWE. Scoping their needs included conducting interviews with three CWE so that they could contribute to the overall intervention content. In phase two, six of these parents evaluated COSI, reviewing and feeding back on COSI until parental approval for content and functionality was achieved. Results: In phase one, a range of adaptations was made to the content and presentation of standardised intervention material to acknowledge and emphasise the key seizure-specific issues to ensure COSI best met parents of CWE's needs. Adaptations included embedding parent and child experiences in the intervention, including particular information requested by parents, such as the links between sleep and seizures and managing child and parental anxieties around sleep, as well as developing functionality to personalise the delivery of content. In phase two, parents confirmed that they found the final version of COSI to be functional and appropriate (after one round of review) for use by parents of CWE and that 100% would recommend it to other families who have CWE. Discussion: It is hoped that the use of evidence-based BSIs, adapted to consider salient epilepsy-specific factors, will increase parent-engagement, COSI's relevance for this particular patient group and overall efficacy in improving sleep in CWE. The effectiveness of COSI will be tested in the CASTLE Sleep-E clinical trial (https://castlestudy.org.uk/).

Seizure likelihood varies with day-to-day variations in sleep duration in patients with refractory focal epilepsy: A longitudinal electroencephalography investigation

BACKGROUND

While the effects of prolonged sleep deprivation (≥24 h) on seizure occurrence has been thoroughly explored, little is known about the effects of day-to-day variations in the duration and quality of sleep on seizure probability. A better understanding of the interaction between sleep and seizures may help to improve seizure management.

METHODS

To explore how sleep and epileptic seizures are associated, we analysed continuous intracranial electroencephalography (EEG) recordings collected from 10 patients with refractory focal epilepsy undergoing ordinary life activities between 2010 and 2012 from three clinical centres (Austin Health, The Royal Melbourne Hospital, and St Vincent's Hospital of the Melbourne University Epilepsy Group). A total of 4340 days of sleep-wake data were analysed (average 434 days per patient). EEG data were sleep scored using a semi-automated machine learning approach into wake, stages one, two, and three non-rapid eye movement sleep, and rapid eye movement sleep categories.

FINDINGS

Seizure probability changes with day-to-day variations in sleep duration. Logistic regression models revealed that an increase in sleep duration, by 1·66 ± 0·52 h, lowered the odds of seizure by 27% in the following 48 h. Following a seizure, patients slept for longer durations and if a seizure occurred during sleep, then sleep quality was also reduced with increased time spent aroused from sleep and reduced rapid eye movement sleep.

INTERPRETATION

Our results suggest that day-to-day deviations from regular sleep duration correlates with changes in seizure probability. Sleeping longer, by 1·66 ± 0·52 h, may offer protective effects for patients with refractory focal epilepsy, reducing seizure risk. Furthermore, the occurrence of a seizure may disrupt sleep patterns by elongating sleep and, if the seizure occurs during sleep, reducing its quality.

Ambulatory EEG Usefulness in Epilepsy Management

SUMMARY

Long-term video-EEG monitoring has been the gold standard for diagnosis of epileptic and nonepileptic events. Medication changes, safety, and a lack of recording EEG in one's habitual environment may interfere with diagnostic representation and subsequently affect management. Some spells defy standard EEG because of ultradian and circadian times of occurrence, manifest nocturnal expression of epileptiform activity, and require classification for clarifying diagnostic input to identify optimal treatment. Some patients may be unaware of seizures, have frequent events, or subclinical seizures that require quantification before optimal management. The influence on antiseizure drug management and clinical drug research can be enlightened by long-term outpatient ambulatory EEG monitoring. With recent governmental shifts to focus on mobile health, ambulatory EEG monitoring has grown beyond diagnostic capabilities to target the dynamic effects of medical and nonmedical treatment for patients with epilepsy in their natural environment. Furthermore, newer applications in ambulatory monitoring include additional physiologic parameters (e.g., sleep, detection of myogenic signals, etc.) and extend treatment relevance to patients beyond seizure reduction alone addressing comorbid conditions. It is with this focus in mind that we direct our discussion on the present and future aspects of using ambulatory EEG monitoring in the treatment of patients with epilepsy.

The impact of antiseizure medications on polysomnographic parameters: a systematic review and meta-analysis

BACKGROUND

Oral antiseizure medications (ASMs) are first-line treatments for patients with epilepsy. However, ASMs may alter sleep architecture, adversely affecting patient outcomes. The meta-analysis aimed to elucidate the effect of ASMs on sleep architecture.

METHODS

PubMed, Embase, and Cochrane Central database (up to Febrary 2021) were searched for randomized control trials (RCT) with effects of ASMs on polysomnography parameters. A meta-analysis using a random-effects model was performed. We did not set limitation to the participants with underlying diagnosis of epilepsy.

RESULTS

Eighteen randomized-controlled trials fulfilled the eligibility criteria. The effects of five main groups of ASMs (sodium channel blockers, calcium channel blockers, GABA enhancers, synaptic vesicle glycoprotein 2A [SV2A] ligand, and broad-spetrum ASMs) on slow-wave sleep (SWS), rapid eye movement (REM) sleep, and sleep efficiency (SE) were analyzed. Compared with placebo, calcium channel blockers and GABA enhancers significantly increased SWS. GABA enhancers also decreased REM sleep percentage, whereas calcium channel blockers significantly increased SE. Sodium channel blockers, SV2A ligand and broad-spectrum ASMs did not affect SWS, REM sleep, or SE. The subgroup analysis revealed that gabapentin, pregabalin, and tiagabine increased the percentage of SWS. Tiagabine also decreased REM sleep, whereas pregabalin increased SE. Finally, levetiracetam did not affect SWS, REM sleep, and SE.

CONCLUSIONS

This meta-analysis indicated that ASMs can have a statistically significant effect on sleep parameters; the effect differs between ASMs.

Rapid eye movement sleep disturbance in patients with refractory epilepsy: A polysomnographic study

OBJECTIVE/BACKGROUND

Patients with epilepsy have disrupted sleep architecture and a higher prevalence of sleep disturbance. Moreover, obstructive sleep apnea (OSA) is more common among patients with refractory epilepsy. Few studies have compared subjective sleep quality, sleep architecture, and prevalence of OSA between patients with refractory epilepsy and those with medically controlled epilepsy. Therefore, this study aimed to evaluate the differences in sleep quality, sleep architecture, and prevalence of OSA between patients with refractory epilepsy and patients with medically controlled epilepsy.

PATIENTS

This retrospective case-control study included 38 patients with refractory epilepsy and 96 patients with medically controlled epilepsy. Sleep parameters and indices of sleep-related breathing disorders were recorded by standard in-laboratory polysomnography. The scores from sleep questionnaires on sleep quality and daytime sleepiness were compared between the two groups.

RESULTS

Patients with refractory epilepsy versus medically controlled epilepsy had statistically significantly decreased rapid eye movement (REM) sleep (13.5 ± 6.1% vs. 16.2 ± 6.1%) and longer REM latency (152.2 ± 84.1 min vs. 117.2 ± 61.9 min). Further, no differences were found in the prevalence of sleep-related breathing disorders, subjective sleep quality, prevalence of daytime sleepiness, and quality of life. Although not statistically significant, patients with refractory epilepsy have a lower rate of OSA compared with those with medically controlled epilepsy (21.1% vs. 30.2%).

CONCLUSIONS

Patients with refractory epilepsy had more disrupted REM sleep regulation than those with medically controlled epilepsy. Although patients with epilepsy have a higher risk of OSA, in this study patients with refractory epilepsy were not susceptible to OSA.

Design and implementation of electronic health record common data elements for pediatric epilepsy: Foundations for a learning health care system

OBJECTIVE

Common data elements (CDEs) are standardized questions and answer choices that allow aggregation, analysis, and comparison of observations from multiple sources. Clinical CDEs are foundational for learning health care systems, a data-driven approach to health care focused on continuous improvement of outcomes. We aimed to create clinical CDEs for pediatric epilepsy.

METHODS

A multiple stakeholder group (clinicians, researchers, parents, caregivers, advocates, and electronic health record [EHR] vendors) developed clinical CDEs for routine care of children with epilepsy. Initial drafts drew from clinical epilepsy note templates, CDEs created for clinical research, items in existing registries, consensus documents and guidelines, quality metrics, and outcomes needed for demonstration projects. The CDEs were refined through discussion and field testing. We describe the development process, rationale for CDE selection, findings from piloting, and the CDEs themselves. We also describe early implementation, including experience with EHR systems and compatibility with the International League Against Epilepsy classification of seizure types.

RESULTS

Common data elements were drafted in August 2017 and finalized in January 2020. Prioritized outcomes included seizure control, seizure freedom, American Academy of Neurology quality measures, presence of common comorbidities, and quality of life. The CDEs were piloted at 224 visits at 10 centers. The final CDEs included 36 questions in nine sections (number of questions): diagnosis (1), seizure frequency (9), quality of life (2), epilepsy history (6), etiology (8), comorbidities (2), treatment (2), process measures (5), and longitudinal history notes (1). Seizures are categorized as generalized tonic-clonic (regardless of onset), motor, nonmotor, and epileptic spasms. Focality is collected as epilepsy type rather than seizure type. Seizure frequency is measured in nine levels (all used during piloting). The CDEs were implemented in three vendor systems. Early clinical adoption included 1294 encounters at one center.

SIGNIFICANCE

We created, piloted, refined, finalized, and implemented a novel set of clinical CDEs for pediatric epilepsy.

Depression is a major determinant of sleep abnormalities in patients with epilepsy

ABSTRACT Introduction: We aimed to identify sleep disorders in patients with epilepsy and compare this group with a healthy population. We also analyzed the features of sleep disorders in patients with epilepsy to demonstrate the effect of seizures and seizure types on sleep. Methods: Our study assessed 43 patients with epilepsy and 53 age- and gender-matched healthy controls. The demographic and clinical data of all participants were recorded. The Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (PSQI), International Restless Legs Syndrome Study Group Rating Scale, Berlin Questionnaire, and Beck Depression Inventory (BDI) were administered to all study subjects. The interview used to evaluate insomnia is based on the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition - DSM-5 diagnostic criteria. Results: Twenty-four patients (55.8%) and 26 controls (49.1%) are women. The mean age of patients and controls was 34.2±11.37 (16-71) and 34.6±11.28 (16-77), respectively. Patients with epilepsy had depression more often than controls, a result that was statistically significant (p<0.0001). We found no statistically significant difference between sleep parameters of patients and controls with normal BDI scores (p>0.05). Patients with depression had worse results on the Berlin Questionnaire and PSQI total score, with statistical significance (p=0.002). Nocturnal seizures, seizure type, and drug treatment had no effect on sleep (p>0.05). Conclusion: We concluded that depression rather than epilepsy negatively affects sleep, suggesting that all patients should be asked about their mood and sleep complaints.

Seizure Onset Zone Lateralization Using a Non-linear Analysis of Micro vs. Macro Electroencephalographic Recordings During Seizure-Free Stages of the Sleep-Wake Cycle From Epilepsy Patients

The application of non-linear signal analysis techniques to biomedical data is key to improve our knowledge about complex physiological and pathological processes. In particular, the use of non-linear techniques to study electroencephalographic (EEG) recordings can provide an advanced characterization of brain dynamics. In epilepsy these dynamics are altered at different spatial scales of neuronal organization. We therefore apply non-linear signal analysis to EEG recordings from epilepsy patients derived with intracranial hybrid electrodes, which are composed of classical macro contacts and micro wires. Thereby, these electrodes record EEG at two different spatial scales. Our aim is to test the degree to which the analysis of the EEG recorded at these different scales allows us to characterize the neuronal dynamics affected by epilepsy. For this purpose, we retrospectively analyzed long-term recordings performed during five nights in three patients during which no seizures took place. As a benchmark we used the accuracy with which this analysis allows determining the hemisphere that contains the seizure onset zone, which is the brain area where clinical seizures originate. We applied the surrogate-corrected non-linear predictability score (ψ), a non-linear signal analysis technique which was shown previously to be useful for the lateralization of the seizure onset zone from classical intracranial EEG macro contact recordings. Higher values of ψ were found predominantly for signals recorded from the hemisphere containing the seizure onset zone as compared to signals recorded from the opposite hemisphere. These differences were found not only for the EEG signals recorded with macro contacts, but also for those recorded with micro wires. In conclusion, the information obtained from the analysis of classical macro EEG contacts can be complemented by the one of micro wire EEG recordings. This combined approach may therefore help to further improve the degree to which quantitative EEG analysis can contribute to the diagnostics in epilepsy patients.

Low-Dose Perampanel Rescues Cortical Gamma Dysregulation Associated With Parvalbumin Interneuron GluA2 Upregulation in Epileptic Syngap1+/- Mice

BACKGROUND

Loss-of-function SYNGAP1 mutations cause a neurodevelopmental disorder characterized by intellectual disability and epilepsy. SYNGAP1 is a Ras GTPase-activating protein that underlies the formation and experience-dependent regulation of postsynaptic densities. The mechanisms that contribute to this proposed monogenic cause of intellectual disability and epilepsy remain unresolved.

METHODS

We established the phenotype of the epileptogenesis in a Syngap1^+/- mouse model using 24-hour video electroencephalography (vEEG)/electromyography recordings at advancing ages. We administered an acute low dose of perampanel, a Food and Drug Administration-approved AMPA receptor (AMPAR) antagonist, during a follow-on 24-hour vEEG to investigate the role of AMPARs in Syngap1 haploinsufficiency. Immunohistochemistry was performed to determine the region- and location-specific differences in the expression of the GluA2 AMPAR subunit.

RESULTS

A progressive worsening of the epilepsy with emergence of multiple seizure phenotypes, interictal spike frequency, sleep dysfunction, and hyperactivity was identified in Syngap1^+/- mice. Interictal spikes emerged predominantly during non-rapid eye movement sleep in 24-hour vEEG of Syngap1^+/- mice. Myoclonic seizures occurred at behavioral-state transitions both in Syngap1^+/- mice and during an overnight EEG from a child with SYNGAP1 haploinsufficiency. In Syngap1^+/- mice, EEG spectral power analyses identified a significant loss of gamma power modulation during behavioral-state transitions. A significant region-specific increase of GluA2 AMPAR subunit expression in the somas of parvalbumin-positive interneurons was identified.

CONCLUSIONS

Acute dosing with perampanel significantly rescued behavioral state-dependent cortical gamma homeostasis, identifying a novel mechanism implicating Ca²⁺-impermeable AMPARs on parvalbumin-positive interneurons underlying circuit dysfunction in SYNGAP1 haploinsufficiency.

Changes in Physiological and Pathological Behaviours Produced by Deep Microelectrode Implantation Surgery in Rats: A Temporal Analysis

Physiological behaviours such as the sleep-wake cycle and exploratory behaviours are important parameters in intact and sham-operated animals and are usually thought to be unaffected by experimental protocols in which neurosurgery is performed. However, there is insufficient evidence in the literature on the behavioural and cognitive effects observed after deep microelectrode implantation surgery in animal models of neurological diseases. Similarly, in studies that utilize animal models of neurological diseases, the impact of surgery on the pathological phenomena being studied is often minimized. Based on these considerations, we performed a temporal analysis of the effects of deep microelectrode implantation surgery in the hippocampus of rats on quiet wakefulness, sleep, and exploratory activity and the pathological behaviours such as convulsive seizures according to the Racine scale. Male Wistar rats (210-300 g) were used and grouped in sham and epileptic animals. Single doses of pilocarpine hydrochloride (2.4 mg/2 μl; i.c.v.) were administered to the animals to generate spontaneous and recurrent seizures. Deep microelectrode implantation surgeries in both groups and analysis of Fast ripples were performed. Physiological and pathological behaviours were recorded through direct video monitoring of animals (24/7). Our principal findings showed that in epileptic animals, one of the main behaviours affected by surgery is sleep; as a consequence of this behavioural change, a decrease in exploratory activity was also found as well as the mean time spent daily in seizures of scale 4 and the number of seizure events of scales 4 and 5 was increased after surgery. No significant correlations between the occurrence of FR and seizure events of scale 4 (rho 0.63, p value 0.25) or 5 (rho -0.7, p value 0.18) were observed. In conclusion, microelectrode implantation surgeries modified some physiological and pathological behaviours; therefore, it is important to consider this fact when it is working with animal models.

Group-based cognitive behavioral therapy program for improving poor sleep quality and quality of life in people with epilepsy: A pilot study

Sleep difficulties are commonly reported by patients with epilepsy and can have a detrimental impact on overall quality of life. The purpose of this pilot study was to assess the efficacy of a psychotherapeutic approach, namely Cognitive Behavioral Therapy for Insomnia (CBT-I), in improving sleep quality in patients with epilepsy. Twenty outpatients with epilepsy who reported poor sleep quality were randomized to either a control or CBT-I treatment group, which involved four group-based CBT-I sessions, delivered on a weekly basis. In addition to completing a range of standardized measures related to sleep quality and quality of life, participants also monitored their sleep with a self-completed sleep diary over a two-week period, on two separate occasions. Following CBT-I treatment, no between-group difference was found on any sleep or quality of life measure. However, both the treatment and control groups improved on measures of sleep quality, quality of life, sleep hygiene behaviors, and dysfunctional beliefs about sleep. These findings suggest that sleep monitoring alone may have the potential for prompting healthy behavior change in this clinical population.

Cortical functional connectivity indexes arousal state during sleep and anesthesia

Disruption of cortical connectivity likely contributes to loss of consciousness (LOC) during both sleep and general anesthesia, but the degree of overlap in the underlying mechanisms is unclear. Both sleep and anesthesia comprise states of varying levels of arousal and consciousness, including states of largely maintained conscious experience (sleep: N1, REM; anesthesia: sedated but responsive) as well as states of substantially reduced conscious experience (sleep: N2/N3; anesthesia: unresponsive). Here, we tested the hypotheses that (1) cortical connectivity will exhibit clear changes when transitioning into states of reduced consciousness, and (2) these changes will be similar for arousal states of comparable levels of consciousness during sleep and anesthesia. Using intracranial recordings from five adult neurosurgical patients, we compared resting state cortical functional connectivity (as measured by weighted phase lag index, wPLI) in the same subjects across arousal states during natural sleep [wake (WS), N1, N2, N3, REM] and propofol anesthesia [pre-drug wake (WA), sedated/responsive (S), and unresponsive (U)]. Analysis of alpha-band connectivity indicated a transition boundary distinguishing states of maintained and reduced conscious experience in both sleep and anesthesia. In wake states WS and WA, alpha-band wPLI within the temporal lobe was dominant. This pattern was largely unchanged in N1, REM, and S. Transitions into states of reduced consciousness N2, N3, and U were characterized by dramatic changes in connectivity, with dominant connections shifting to prefrontal cortex. Secondary analyses indicated similarities in reorganization of cortical connectivity in sleep and anesthesia. Shifts from temporal to frontal cortical connectivity may reflect impaired sensory processing in states of reduced consciousness. The data indicate that functional connectivity can serve as a biomarker of arousal state and suggest common mechanisms of LOC in sleep and anesthesia.

Sleep pattern in epilepsy patients: a polysomnographic study

Background

Sleep disorders and epilepsy commonly exist and affect each other. Patients with epilepsy often complain of poor sleep and on the other hand, poor sleep makes epilepsy control difficult.

Objectives

We aimed at comparing the sleep disturbances in a group of patients with medically controlled epilepsy versus another group with medically refractory epilepsy, from the electrophysiological standpoint.

Subjects and methods

Sixty epilepsy patients were included; half of them with controlled epilepsy were assigned as group I, and the other half with refractory epilepsy was assigned as group II. All patients had an overnight polysomnogram and sleep EEG done. We excluded any patient with abnormal general or neurological clinical examination.

Results

Patients in group II, had significantly delayed sleep onset latency and REM latency. However, higher arousal index, insomnia, and periodic limb movement index were found to be significantly higher in group I. Respiratory events; as light sleep durations, were observed to be higher in Group II, in addition to apnea-hypopnea index that was significantly higher in this group.

Conclusion

Epilepsy affects sleep architecture and sleep-related events. Patients with refractory epilepsy suffer from more disturbance in sleep patterns. Moreover, antiepileptic drugs can have a diverse effect on sleep architecture and quality in epileptic patients.

Breakthrough spikes in rapid eye movement sleep from the epilepsy monitoring unit are associated with peak seizure frequency

Study Objectives

Rapid eye movement sleep (REM) usually suppresses interictal epileptiform discharges (IED) and seizures. However, breakthrough IEDs in REM sometimes continue. We aimed to determine if the amount of IED and seizures in REM, or REM duration, is associated with clinical trajectories.

Methods

Continuous electroencephalogram (EEG) recordings from the epilepsy monitoring unit (EMU) were clipped to at least 3 h of concatenated salient findings per day including all identified REM. Concatenated EEG files were analyzed for nightly REM duration and the “REM spike burden” (RSB), defined as the proportion of REM occupied by IED or seizures. Patient charts were reviewed for clinical data, including patient-reported peak seizure frequency. Logistic and linear regressions were performed, as appropriate, to explore associations between two explanatory measures (duration of REM and RSB) and six indicators of seizure activity (clinical trajectory outcomes).

Results

The median duration of REM sleep was 43.3 (IQR 20.9–73.2) min per patient per night. 59/63 (93.7%) patients achieved REM during EMU admission. 39/59 (66.1%) patients had breakthrough IEDs or seizures in REM with the median RSB at 0.7% (IQR 0%–8.4%). Every 1% increase in RSB was associated with 1.69 (95% CI = 0.47–2.92) more seizures per month during the peak seizure period of one’s epilepsy (p = 0.007).

Conclusions

Increased epileptiform activity during REM is associated with increased peak seizure frequency, suggesting an overall poorer epilepsy trajectory. Our findings suggest that RSB in the EMU is a useful biomarker to help guide about what to expect over the course of one’s epilepsy.

Behavioral-educational sleep interventions for pediatric epilepsy: a randomized controlled trial

Study Objectives

To evaluate the effect of a clinic-based, behavioral-educational sleep intervention on sleep of children with epilepsy, maternal knowledge about childhood sleep, and maternal sleep quality.

Methods

A total of 100 toddlers and preschool-age children with epilepsy (1.5–6 years, 55% boys) and their parents were randomized to receive sleep intervention (n = 50) or usual care with attention (n = 50). Outcomes were assessed at baseline, 3, 6, and 12 months after intervention with the use of objective actigraphy, Children’s Sleep Habits Questionnaire, Parents’ Sleep Knowledge Inventory, and Pittsburgh Sleep Quality Index. Intervention effects were examined using general linear models for repeated measurements to compare the mean change in outcomes from baseline to 12 months post-intervention between the two groups.

Results

Sleep intervention resulted in children having greater sleep efficiency by 2.03% compared with the usual care group (95% CI = 0.20% to 3.86%; p = .03). Children in the intervention group also had significantly longer total nighttime sleep as objectively assessed by actigraphy than did those in the usual care group, with an adjusted mean difference of 16.13 minutes (95% CI = 0.24% to 32.03%; p = .04). No intervention effects were observed for maternal knowledge about childhood sleep, and maternal sleep quality.

Conclusion

Sleep intervention provided during routine neurologic visits results in significant, measurable, and sustained benefits in sleep quality and quantity in children with epilepsy. Future trials are warranted to evaluate whether improvements in sleep could impact health-related quality of life or other aspects of functioning in children with epilepsy.

Clinical Trial

This trial has been registered at www.clinicaltrials.gov (trial name: Sleep Intervention for Pediatric Epilepsy; registration number: NCT02514291).

Sleep and circadian defects in a Drosophila model of mitochondrial encephalomyopathy

Mitochondrial encephalomyopathies (ME) are complex, incurable diseases characterized by severe bioenergetic distress that can affect the function of all major organ systems but is especially taxing to neuromuscular tissues. Animal models of MEs are rare, but the Drosophila ATP6¹ mutant is a stable, well-characterized genetic line that accurately models progressive human mitochondrial diseases such as Maternally-Inherited Leigh Syndrome (MILS), Neuropathy, Ataxia, and Retinitis Pigmentosa (NARP), and Familial Bilateral Striatal Necrosis (FBSN). While it is established that this model exhibits important hallmarks of ME, including excess cellular and mitochondrial reactive oxygen species, shortened lifespan, muscle degeneration, and stress-induced seizures, it is unknown whether it exhibits defects in sleep or circadian function. This is a clinically relevant question, as many neurological and neurodegenerative diseases are characterized by such disturbances, which can exacerbate other symptoms and worsen quality of life. Since Drosophila is highly amenable to sleep and circadian studies, we asked whether we could detect disease phenotypes in the circadian behaviors of ATP6¹. Indeed, we found that day-time and night-time activity and sleep are altered through disease progression, and that circadian patterns are disrupted at both the behavioral and neuronal levels. These results establish ATP6¹ as an important model of sleep and circadian disruption in ME that can be studied mechanistically at the molecular, cellular, and behavioral level to uncover underlying pathophysiology and test novel therapies.

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A Drosophila model of mitochondrial disease (ATP6¹) displays altered sleep patterns.

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ATP6¹ sleep quantity and consolidation are reduced in advanced disease.

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ATP6¹ is behaviorally arrhythmic under conditions of constant darkness.

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Selected neurons of the circadian circuit display altered daily firing rates in ATP6¹.

Neuroendocrine aspects of improving sleep in epilepsy

Sleep plays an intricate role in epilepsy and can affect the frequency and occurrence of seizures. With nearly 35% of U.S. adults failing to obtain the recommended 7 h of sleep every night, understanding the complex relationship between sleep and epilepsy is of utmost relevance. Sleep deprivation is a common trigger of seizures in many persons with epilepsy and sleep patterns play a role in the occurrence of seizures. Some patients have their first seizure or repeated seizures after an "all-nighter" at college or after a long period of chronic sleep deprivation. The strength of the relationship between sleep and seizures varies between patients, but improving sleep and optimizing seizure control can have significant positive effects on the quality of life for all these patients. Research has shown that the changes in the brain's electrical and hormonal activity occurring during normal sleep-wake cycles can be linked to both sleep and seizure patterns. Many questions remain to be answered about sleep and epilepsy. How can sleep deprivation trigger an epileptic seizure? How do circadian and hormonal changes influence sleep pattern and seizure occurrence? Can hormones or sleeping pills help with sleep in epilepsy? In this article we discuss these and many other questions on sleep in epilepsy, with an emphasis on sleep architecture, hormone changes, mechanistic factors, and possible prevention strategies.

Effects of agomelatine on electrocorticogram activity on penicillin-induced seizure model of rats

Agomelatine is a new antidepressant drug acting as an antagonist of 5-hydroxytryptamine receptor 2C (5-HTR_2C) and agonist of melatonergic receptors 1 and 2 (MT₁ and MT₂). Because of this dual action, it is an atypical antidepressant. The aim of this study was to investigate chronic anticonvulsant effects of agomelatine on penicillin-induced epilepsy model. Adult male Sprague-Dawley rats divided into four groups and were administered with tap water (vehicle), and agomelatine doses of 10 mg/kg, 50 mg/kg and 100 mg/kg for 14 days via oral gavage. After the last doses were given, epileptic seizures were induced by intracortical penicillin (500 IU/2.5 μl) application in rats under urethane (1.25 g/kg intraperitoneal) anesthesia. Electrocorticogram (ECoG) recordings were obtained from the somatomotor cortex through 90 min, and spike frequencies and amplitudes were analyzed. The spike frequency analyses revealed that only 50 mg/kg agomelatine administration decreased the spike frequencies of hypersynchronous discharge of neurons caused by penicillin (p < 0.05). No significant differences in amplitudes between experimental groups were observed. In addition, mRNA expressions of vesicular glutamate transporter 1 (VGLUT1) and vesicular gamma-aminobutyric acid transporter (VGAT) in response to the agomelatine active dose, 50 mg/kg, showed no significant effect of agomelatine on the mRNA expression. Our results indicate that chronic treatment with agomelatine may have potential anticonvulsant effects. Agomelatine may be a promising drug for epilepsy patients having depression due to its antiepileptic and antidepressant effects.

Small Lesion Size Is Associated with Sleep-Related Epilepsy in Focal Cortical Dysplasia Type II

Objective

To investigate the neuroimaging and clinical features associated with sleep-related epilepsy (SRE) in patients with focal cortical dysplasia (FCD) type II.

Methods

Patients with histopathologically proven FCD type II were included from three epilepsy centers. SRE was defined according to the video EEG findings and seizure history. Cortical surface reconstruction and volume calculation were performed using FreeSurfer. The lesions were manually delineated on T1 volumetric MRI using the ITK-SNAP software. The lesion volumes were normalized by the intracranial volume of each patient. The lesions were classified as small or large by placing a threshold based on quantitative (whether the lesion was detected on MRI report) and qualitative (volume) criteria.

Results

A total of 77 consecutive patients were included. Of them, 36 had SRE and 41 had non-SRE. An earlier age of epilepsy onset, high seizure frequency, regional interictal EEG findings, and favorable surgical outcome were characteristic in both groups. Small lesions were defined as those having a volume <3,217 mm³. In total, 60.9% of the patients with SRE (25/41) had small FCD lesion, which was significantly higher than the non-SRE group (9/34, 26.5%, p = 0.005). Small lesion size was the only predictor significantly associated with SRE in the overall type II group by multivariate analyses (p = 0.016). Although the proportion of patients who had frontal FCD and SRE was higher than non-frontal FCD (54.5 vs. 27.3%, p = 0.043), the relationship between SRE and lesion location was not confirmed by multivariate analysis. Thalamic volume and seizure semiology were not statistically different between the SRE and non-SRE group. The significant association between lesion size and SRE was reproducible in type IIb and IIa subgroups.

Significance

SRE is common in patients with FCD type II. Small FCD type II lesions are significantly associated with SRE. Although our findings cannot be applied to the entire spectrum of SRE, potential existence of small FCD lesions should be considered when evaluating patients with SRE, and utilization of all other supportive electroclinical information for lesion detection is highly desirable.

The Mutual Interaction Between Sleep and Epilepsy on the Neurobiological Basis and Therapy

BACKGROUND

Sleep and epilepsy are mutually related in a complex, bidirectional manner. However, our understanding of this relationship remains unclear.

RESULTS

The literatures of the neurobiological basis of the interactions between sleep and epilepsy indicate that non rapid eye movement sleep and idiopathic generalized epilepsy share the same thalamocortical networks. Most of neurotransmitters and neuromodulators such as adenosine, melatonin, prostaglandin D2, serotonin, and histamine are found to regulate the sleep-wake behavior and also considered to have antiepilepsy effects; antiepileptic drugs, in turn, also have effects on sleep. Furthermore, many drugs that regulate the sleep-wake cycle can also serve as potential antiseizure agents. The nonpharmacological management of epilepsy including ketogenic diet, epilepsy surgery, neurostimulation can also influence sleep.

CONCLUSION

In this paper, we address the issues involved in these phenomena and also discuss the various therapies used to modify them.

High risk of developing subsequent epilepsy in patients with sleep-disordered breathing

Purpose

Sleep-disordered breathing (SDB) is often associated with other medical disorders. Whether SDB interacts with other factors for developing subsequent epilepsy remains unclear.

Methods

This population-based cohort study was conducted using the National Health Insurance Research Database of Taiwan. Patients aged >20 years and diagnosed with SDB between 2000 and 2010 comprised the SDB cohort (n = 138,507), and their data were compared with those of the comparison cohort (n = 138,507). The adjusted hazard ratio (aHR) for epilepsy was calculated using a multivariate Cox proportional hazards model.

Results

The SDB cohort had an increased risk of epilepsy (aHR = 1.50, 95% confidence interval [CI] = 1.36–1.66). The sex-stratified analysis revealed a significant adjusted hazard ratio (aHR) for epilepsy with a 1.51-fold higher risk for female patients, and also a significantly 1.49-fold higher risk for male patients in the SDB cohort. Although epilepsy incidence increased with age in both cohorts, different age groups in the SDB cohort all had a significantly higher risk of developing epilepsy than comparison cohort.

Conclusion

This population-based cohort study indicates that patients with SDB are at a high risk of developing subsequent epilepsy, in both sexes and all age groups.

Comorbidity and Childhood Epilepsy: A Nationwide Registry Study

BACKGROUND AND OBJECTIVE

Children with epilepsy are at increased risk of other disorders and difficulties, preceding, cooccurring with, or after the diagnosis of epilepsy. Risk estimates vary, few studies are population-based, and few provide comprehensive assessments of comorbidities. We used nationwide registry data to describe frequencies of medical, neurologic, developmental, and psychiatric conditions occurring before and after children are diagnosed with childhood epilepsy.

METHODS

Data were obtained from the Norwegian Patient Registry, which is an administrative database recording International Classification of Diseases, 10th Revision diagnoses from all government-funded specialist health services in Norway (outpatient consultations and hospitalizations). We included data from the years 2008 through 2013 for all children born in Norway between 1996 and 2013 (0-17 years of age at the end of follow-up). Children with epilepsy were compared with the general child population, adjusting for sex and age. We also compared children with complicated epilepsies (ie, epilepsies with additional neurologic and/or developmental disorders) to children with uncomplicated epilepsies.

RESULTS

The study population included 1 125 161 children. There were 6635 (0.6%) children with epilepsy. Nearly 80% of children with epilepsy had ≥1 comorbid disorder. All types of disorders were more frequent in children with epilepsy, with additional medical disorders recorded in 55%, neurologic disorders in 41%, and developmental/psychiatric disorders in 43%. Children with complicated epilepsies had the highest overall levels of comorbidity, but the risk of medical and psychiatric comorbidities was also substantial among children with uncomplicated epilepsies.

CONCLUSIONS

The overall frequency of comorbid disease is high in children with epilepsy, including children with presumably uncomplicated epilepsies.

Neuropsychological consequences of sleep disturbance in children with epilepsy

A growing body of research reveals strong relationships between sleep disturbance, sleep architecture, and neuropsychological functioning in children. Children with epilepsy experience numerous neuropsychological comorbidities, including cognitive deficiencies and emotional/behavioral difficulties; thus, it is reasonable to consider the moderating role of sleep in this population. This review summarizes findings involving the prevalence and characteristics of sleep problems often experienced by children with epilepsy. The complex and bidirectional relationship between sleep and seizure frequency is discussed. Research pertaining to the relationship between sleep disturbance and daytime cognition as well as behavior reveals a substantial association between these variables. Clinically relevant practices related to the assessment and treatment of sleep-related complications are reviewed, and directions for further research involving intervention and assessment are also reviewed.

Assessment of Treatment Side Effects and Quality of Life in People with Epilepsy

Epilepsy impairs quality of life in physical, psychological, cognitive, social, and occupational domains. In people who are not seizure free, depression and adverse medication effects have a predominant role in determining quality of life. The assessment of these factors and other comorbidities is essential for maximizing quality of life in epilepsy. There are multiple tools available to assess medication effects and quality of life in a structured format. Such tools can provide superior assessments and allow clinicians to have a greater impact on their patients' quality of life.

Association of Migraine and Sleep-Related Breathing Disorder: A Population-Based Cohort Study

In this nationwide population-based cohort study, we aimed to evaluate the effects of sleep-related breathing disorders (SBD) on migraine development.Patients ages 20 years or more and diagnosed with SBD between 2000 and 2009 were evaluated as the SBD cohort (n = 3411), and compared with comparison cohort (n = 13,644). The adjusted hazard ratio (aHR) for developing migraine was calculated in both cohorts by multivariate Cox proportional hazards model.The cumulative incidence of migraine was significantly higher in the SBD cohort than in the comparison cohort. In the SBD cohort, the overall aHR for developing migraine was 2.43 (95% confidence interval [CI] = 1.72-3.44). The risk of developing migraine was higher in men (aHR 2.71) than in women (aHR 2.29) with SBD. When stratifying by age, we observed increased incidence of migraine in patients ages 20 to 44 years and 45 to 64 years, with a higher aHR of 2.51 (95% CI = 1.47-4.30) and 2.68 (95% CI = 1.63-4.43), respectively. The risk of developing migraine in the patients with SBD with or without comorbidity exhibited nonsignificant differences. After stratifying by the use of hypnotics, the aHR for developing migraine was 2.39 in the patients with hypnotics use and 3.58 in the patients without hypnotics use.Our findings indicate increased risk of developing migraine in adults, but not elderly ones, with SBD.