Excessive Daytime Sleepiness and Sleep Disorders in a Population of Patients with Epilepsy: a Case-Control Study

Duration of N1 sleep is a factor for excessive daytime sleepiness in epilepsy patients with interictal epileptiform discharges: A polysomnographic study

Purpose

This study aimed to identify the occurrence of excessive daytime sleepiness (EDS) in epilepsy patients with interictal epileptiform discharges and to explore the impact of interictal sleep architecture and sleep-related events on EDS.

Methods

This study included 101 epilepsy patients with interictal epileptiform discharges (IED) and 100 control patients who underwent simultaneous polysomnography and video ambulatory electroencephalography for >7 h throughout a single night. Multiple sleep latency tests were used to assess EDS. Comorbid EDS was present in 25 and 11 patients in the IED epilepsy and control groups, respectively. In addition, univariate and multivariate logistic regression analyses were performed to explore the factors influencing EDS.

Results

The epilepsy group had a higher prevalence of comorbid EDS and shorter R sleep duration. Univariate logistic regression analysis indicated that an increased risk of EDS may be associated with prolonged N1 sleep duration, higher arousal index, lower mean saturation (mSaO2), higher oxygen desaturation index (ODI), and duration of wake after sleep onset (WASO). Multivariate logistic regression analysis revealed that N1 sleep duration was significantly correlated with EDS.

Conclusion

In epilepsy patients with IED, the arousal index, mSaO2, ODI, and duration of WASO were weakly correlated with EDS, and the duration of N1 sleep demonstrated a significant positive correlation with EDS, which requires further research.

Hypocretin-1/orexin-A, sleep and excessive daytime sleepiness in patients with nonconvulsive status epilepticus: A cross-sectional cohort study

BACKGROUND AND OBJECTIVES

Nonconvulsive status epilepticus (NCSE) manifests as a change in mental status without a coma (NCSE proper) or comatose NCSE. Hypocretin-1/orexin-A (H/O) is involved in alertness and sleep maintenance. Sleep impairment and excessive daytime sleepiness (EDS) have a negative impact on cognitive functions and activities of daily living (ADL).

METHODS

Patients meeting the NCSE criteria underwent cerebrospinal fluid and brain magnetic resonance imaging examinations, polysomnographies (PSG), multiple latency sleep tests (MSLT), and completed Epworth Sleepiness Scale (ESS). Montreal Cognitive Assessment was used to evaluate cognitive functions, and the Barthel Index was used to assess ADL in the acute phase (V1) and three months follow-up (V2).

RESULTS

From May 2020 to May 2023, we enrolled 15 patients, eight (53.3 %) women, with a median age of 69 (14) years. The median H/O CSF concentration was 250 (63.6) pg/ml; however, only three CSF samples (20 %) decreased below the borderline concentration of 200 pg/ml. Fourteen out of 15 patients (93.3 %) completed the PSG study. The median of wakefulness after sleep onset was 167 (173.5) min, sleep efficiency (SE) was 62.9 (63) %, sleep latency (SL) was 6 (32) min, REM sleep was 2.85 (7.2) %, and REM first episode latency was 210.5 (196.5) minutes. The medians of the stages N1 NREM were 4.65 (15) %, N2 NREM 68.4 (29.9) %, and N3 NREM 21.8 (35.5) %. MSLT mean latency was 7.7 (12.6) minutes. A significant negative correlation exists between H/O CSF concentrations and the stage N1 NREM (rs = -0.612, p = 0.02), and the proportion of cumulative sleep time with oxygen saturation below 90 % in total sleep time (TST) t90 (rs = -0.57, p = 0.03). MSLT had significant negative correlation with TST (rs = -0.5369, p = 0.0478), with SE (rs = -0.5897, p = 0.0265), with apnea-hypopnea index (rs = -0.7631, p = 0.0002) and with deoxygenation index (rs = -0.8009, p = 0.0006). A positive correlation exists between MSLT and SL (rs = 0.6284, p = 0.0161) and between ESS and t90 (rs = 0.9014, p = 0.0004). The correlation between H/O CSF concentrations and EDS, cognitive performance, and ADL was not proved.

CONCLUSIONS

Patients after NCSE exhibited sleep impairment and excessive daytime sleepiness. Hypocretin-1/orexin-A concentrations decreased only in 20 % of these cases.

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.

Seizure-related stress and arousal responses mediate a relationship between anxiety trait and state in epilepsy

BACKGROUND

Epilepsy causes substantial psychological distress and anxiety, primarily due to seizures. However, the impact of stress responses and changes in arousal and their association with anxiety patterns in patients with epilepsy (PWE) remains unclear. This study aimed to investigate the relationships among seizures, stress and arousal characteristics, and trait and state anxiety characteristics in PWE.

METHODS

Our sample consisted of 159 outpatients with epilepsy recruited from five institutions in Japan in 2020. Participants completed the State-Trait Anxiety Inventory-Form JYZ (STAI) and the Japanese-Stress Arousal Check List (J-SACL). We analyzed the correlations between inventory scores and clinical information. Using principal component analysis (PCA), we derived epilepsy-specific stress/arousal characteristics, which accounted for high arousal and low-stress levels, termed epilepsy-specific stress or arousal response (ESAR), from the J-SACL scores. We conducted a mediation analysis to assess the mediating role of ESAR in the relationship between traits and state anxiety.

RESULTS

We found significant correlations between J-SACL stress and arousal factors (r = -0.845, p < 0.001), ESAR and seizure frequency (r = -0.29, p < 0.001), ESAR and trait anxiety scores on the STAI (r = -0.77, p < 0.0001), and ESAR and state anxiety scores on the STAI (r = -0.60, p < 0.0001). Mediation analysis supported by the Monte Carlo method revealed that ESAR significantly mediated the association between trait and state anxiety.

CONCLUSIONS

These findings elucidate the epilepsy-specific stress and arousal characteristics and their roles in mediating traits and state anxiety. These results may reflect the long-term clinical course and unique emotion recognition tendencies in epilepsy.

Restless leg syndrome prevalence in epilepsy patients and its impact on quality of sleep

This study aimed to determine the frequency of restless leg syndrome (RLS) and other sleep-related movement disorders and their effects on sleep quality in epilepsy patients. One hundred and twenty-seven epilepsy patients were compared with 115 age-and gender-matched healthy controls. RLS was determined from the clinical characteristics of the patients according to the International RLS Study Group's (IRLSSG) diagnostic criteria. Sleep bruxism was diagnosed based on the International Classification of Sleep Disorders, Third Edition (ICSD-3) criteria. Subjective sleep quality was evaluated with the Pittsburgh Sleep Quality Index (PSQI). Poor sleep quality was more common in the epilepsy group than in the control group (42.5% versus 26.1%; p = 0.007). The epilepsy group had significantly higher PSQI total scores than the control group (p = 0.003). The frequency of RLS was higher in epileptic patients than in the control group (13.4% versus 5.2%; p = 0.024). There were no significant differences between the patient group and the control group regarding limb movement and bruxism frequency during sleep. The PSQI scores were high in epilepsy patients with RLS compared to those without RLS (p = 0.009). The frequency of habitual snoring, bruxism, and repetitive leg movement in sleep was also high in epilepsy patients with RLS compared to those without RLS (p < 0.05). The prevalence of poor sleep quality and RLS in epilepsy patients is higher than in healthy controls. Our results also show the negative impact of RLS on sleep quality in epilepsy patients. Further confirmatory studies using objective sleep tests are needed to identify the mechanisms underlying the current findings.

Gender differences in prevalence and risk factors of sleep disturbances in patients with epilepsy

Background

Sleep disturbances are frequently observed in patients with epilepsy (PWE), with adversely effects on life quality and seizure control. The study aimed to assess the gender differences in incidence and factors of sleep disturbances in PWE.

Methods

PWE confirmed the diagnosis of epilepsy were consecutively enrolled in this cross-sectional study, with detailed information recorded. A group of healthy participants were recruited as the control. Sleep and mood disorders were evaluated with the Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI).

Results

One hundred and thirty-three patients (age: 30.2 ± 10.6 years, men: 51%) and 150 healthy subjects were recruited in this study. Compared with healthy controls, PWE had higher mean scores of the ISI and BDI (p < 0.001 and p = 0.01). There were no significant gender differences in the prevalence and scores of sleep disturbances in PWE. In the overall PWE, nocturnal seizures and focal epilepsy were respectively related to insomnia and poor sleep quality (OR = 3.35, p = 0.024; OR = 3.08, p = 0.013), and mood disorders were also important factors in sleep disturbances (p < 0.05). In the analysis by gender, depression, anxiety, nocturnal seizures and focal epilepsy were associated with insomnia and poor sleep quality in men. For women, however, depression mood was the only factor of sleep disturbances.

Conclusions

Though no gender difference was observed in the incidence of sleep disturbances, factors contributing to insomnia and sleep quality were different by gender. The factors and gender differences of sleep disturbances should be taken into account in the clinical treatment.

High prevalence of pathological alertness and wakefulness on maintenance of wakefulness test in adults with focal-onset epilepsy

BACKGROUND

Excessive daytime sleepiness (EDS) is a common complaint in adults with epilepsy (AWE), but objective evaluation is lacking. We used the maintenance of wakefulness test (MWT) to objectively measure the ability of adults with focal-onset epilepsy to maintain wakefulness in soporific conditions.

METHODS

Adults with epilepsy participating in a study investigating the effects of lacosamide on sleep and wakefulness underwent baseline ambulatory polysomnography (PSG)/EEG followed by MWT. Mean sleep latency (MSL) and mean percent sleep time (MST, mean percentage of non-wake EEG scored in 3-sec bins from lights out to sleep onset averaged over the 4 MWT trials) were quantified. Subjective sleepiness was assessed by the Epworth Sleepiness Scale (ESS). Spearman correlation and linear regression assessed relationships between MWT parameters, ESS and relevant sleep and epilepsy-related variables.

RESULTS

Maintenance of wakefulness test MSL in 51 AWE (mean age 43.5 ± 13 years, 69% female, mean BMI 24.6 ± 11.2 kg/m²) was 21.7 ± 11.9 min; 45.1% had an abnormally short MSL <19.4 min and 15.7% <8 min. MST was 9.3% [3.3, 19.1]. Mean ESS score was 8.8 ± 5.7; 39% had elevated ESS (>10). No correlation between subjective ESS and objective MSL (p = 0.67) or MST (p = 0.61) was found. MSL was significantly shorter in subjects with focal to bilateral tonic-clonic seizures (FBTCS; 7.9 min [13.6, 22.3]) compared to those without (27.4 min [21.2, 33.6], p = 0.013). Younger subjects had shorter MSL; MSL increased 3.2 min for every 10-year increase in age.

CONCLUSION

We found a high prevalence of objective sleepiness/difficulty maintaining wakefulness on the MWT and subjective sleepiness using the ESS in AWE without a correlation between the two. More severe objective sleepiness was found in subjects with a history of FBTCS and younger age. Further research is needed to determine mechanistic underpinnings and optimal measurements of pathological sleepiness in people with epilepsy given the burden of it on quality of life.

Sleep Disruption Worsens Seizures: Neuroinflammation as a Potential Mechanistic Link

Sleep disturbances, such as insomnia, obstructive sleep apnea, and daytime sleepiness, are common in people diagnosed with epilepsy. These disturbances can be attributed to nocturnal seizures, psychosocial factors, and/or the use of anti-epileptic drugs with sleep-modifying side effects. Epilepsy patients with poor sleep quality have intensified seizure frequency and disease progression compared to their well-rested counterparts. A better understanding of the complex relationship between sleep and epilepsy is needed, since approximately 20% of seizures and more than 90% of sudden unexpected deaths in epilepsy occur during sleep. Emerging studies suggest that neuroinflammation, (e.g., the CNS immune response characterized by the change in expression of inflammatory mediators and glial activation) may be a potential link between sleep deprivation and seizures. Here, we review the mechanisms by which sleep deprivation induces neuroinflammation and propose that neuroinflammation synergizes with seizure activity to worsen neurodegeneration in the epileptic brain. Additionally, we highlight the relevance of sleep interventions, often overlooked by physicians, to manage seizures, prevent epilepsy-related mortality, and improve quality of life.

Effects of anti-seizure medications on sleep architecture and daytime sleepiness in patients with epilepsy: A literature review

Anti-seizure medications (ASMs) may improve or be detrimental to sleep. A literature review (as an update to the 2014 review by Jain and Glauser [https://doi.org/10.1111/epi.12478]) of 25 ASMs of interest (articles from 12 ASMs included) on the effect of ASMs/non-drug treatments on sleep in patients with epilepsy was conducted. The most common objective instrument was polysomnography, and the most common subjective measures were the Epworth Sleepiness Scale and the Pittsburgh Sleep Quality Index. Eslicarbazepine acetate, lacosamide, and perampanel improved or had no effect on sleep. Perampanel was associated with low incidence of insomnia, and lacosamide with low incidence of daytime sleepiness adverse events. Clonazepam, felbamate, lamotrigine, oxcarbazepine, and phenobarbital worsened or had no effect on sleep. Lamotrigine may be associated with insomnia risk and phenobarbital with daytime sleepiness. Data for valproic acid were mixed. Overall, cannabidiol, carbamazepine, and levetiracetam had no effect on sleep. Epilepsy surgery may benefit sleep in patients with a good surgical outcome. Some ASMs, and, possibly, epilepsy surgery, may have positive effects on sleep, possibly linked to achieving seizure control. Nonetheless, other ASMs may worsen sleep in some settings. Clinicians should consider such observations when making treatment decisions, particularly for patients with comorbid sleep disorders.

Evaluation of the effectiveness of methylphenidate and modafinil in the treatment of daily drowsiness in patients with refractory epilepsy and their comparison with the control group

BACKGROUND

Various articles show the high prevalence of sleep disorders and especially excessive daytime sleepiness (EDS) in patients with refractory epilepsy and the importance of personal and social burden of this complication on individuals. Considering the insufficient evidence to draw efficacy and safety of modafinil and methylphenidate to treat EDS in the patient with intractable seizures, we decided to compare the effect of methylphenidate and modafinil with the control group. It is hoped that this study will pave the way for further studies.

METHODS

This study is a clinical trial (IRCT20171030037093N22) (URL: https://www.irct.ir/trial/42485). The study population was patients with refractory epilepsy referred to the neurology clinic of Al-Zahra Hospital, Isfahan, Iran, from 2019 to 2020. The patients were randomly divided into three groups. The first group was treated with methylphenidate, the second group was treated with modafinil, and the third group was not received any medication such as modafinil and methylphenidate. Methylphenidate dosage was 10-20 mg/day. The patients were treated with modafinil at a dose of 200-600 mg/day. EPWORTH sleepiness scale (ESS) and Total Sleep Time (TST) were calculated before and 8 weeks after the intervention for the patients.

RESULTS

47 patients were included and divided into 3 groups, methylphenidate (10 males and 9 females), modafinil (7 males and 13 females), and control (4 males and 4 females). There was no significant difference among the groups based on ESS before and after intervention and TST after the intervention (P>0.05), but the mean of TST was significantly lower in the control group than in methylphenidate and modafinil groups before the intervention (P=0.003). The change of ESS and TST before compared to after intervention in the methylphenidate and modafinil group were significant (P<0.001), but the changes of ESS and TST in the control group were not significant (P>0.05). The frequency of complications (P=0.74) and outcomes (P=0.07) were similar in both groups.

CONCLUSION

Modafinil and methylphenidate are two effective and safe drugs to increase the quality of sleep in the patients. Additionally, ESS and TST scores are better in the patients who used modafinil and methylphenidate.

Expert Opinion: Managing sleep disturbances in people with epilepsy

Poor sleep and daytime sleepiness are common in people with epilepsy. Sleep disorders can disrupt seizure control and in turn sleep and vigilance problems can be exacerbated by seizures and by antiepileptic treatments. Nevertheless, these aspects are frequently overlooked in clinical practice and a clear agreement on the evidence-based guidelines for managing common sleep disorders in people with epilepsy is lacking. Recently, recommendations to standardize the diagnostic pathway for evaluating patients with sleep-related epilepsies and comorbid sleep disorders have been presented. To build on these, we adopted the Delphi method to establish a consensus within a group of experts and we provide practical recommendations for identifying and managing poor night-time sleep and daytime sleepiness in people with epilepsy. We recommend that a comprehensive clinical history of sleep habits and sleep hygiene should be always obtained from all people with epilepsy and their bed partners. A psychoeducational approach to inform patients about habits or practices that may negatively influence their sleep or their vigilance levels should be used, and strategies for avoiding these should be applied. In case of a suspected comorbid sleep disorder an appropriate diagnostic investigation should be performed. Moreover, the possible presence of sleep fragmentation induced by sleep-related seizures should be ruled out. Finally, the dose and timing of antiepileptic medications and other co-medications should be optimized to improve nocturnal sleep and avoid daytime sedation.

The Epworth Sleepiness Scale in epilepsy: Internal consistency and disease-related associations

BACKGROUND

The Epworth Sleepiness Scale (ESS) is the most common instrument for measuring subjective sleep propensity in people with epilepsy but has not yet been validated in this population.

STUDY OBJECTIVES

We aimed to systematically assess the validity, performance, and internal consistency of the ESS, as well as correlations between the ESS and disease-specific variables and patient-reported outcome measures in a cohort of adults with epilepsy (AWE).

METHODS

Ninety-five AWE completed sleep and seizure diaries, in-laboratory polysomnography (PSG) and patient-reported outcome measures, including the ESS, Insomnia Severity Index (ISI), and the Beck Depression Inventory (BDI). Demographic information and data from 95 matched controls referred for PSG for suspected obstructive sleep apnea (OSA) was taken from the electronic medical record. Frequencies of high ESS item ratings (item score ≥2) were calculated for each group. Cronbach's α and factor analysis were performed to assess the internal consistency and validity of the ESS within cases and controls. Multivariable linear models were used to assess the association between ESS and predictors of interest, adjusting for demographic and disease-specific variables, including seizure type, frequency, and anti-seizure medication (ASM) therapy.

RESULTS

While suspected OSA controls had significantly greater mean ESS total scores (9.9 vs 7.9, p = 0.004) and proportion with ESS >10 (42% vs 25%, p = 0.014), there were no significant differences in the severity of item responses, with the exception of "lying down to rest in the afternoon when circumstances permit," for which more controls rated as likely/very likely (79% vs 64%), p = 0.024). AWE with ESS >10 had higher mean standardized ASM dose (2.5 vs 1.7, p = 0.026). All ESS items were significantly correlated with the total score within each group. Cronbach's α was 0.75 for cases and 0.85 for controls, indicating good internal consistency of the ESS for both groups. After adjusting for demographic and sleep characteristics, higher ESS scores were associated with greater insomnia scores on the ISI (p = 0.024) and depressive symptoms on the BDI (p = 0.018).

CONCLUSIONS

This study provides validity for the use of the ESS in adult populations with epilepsy.

Sleep quality and daytime sleepiness in epilepsy: Systematic review and meta-analysis of 25 studies including 8,196 individuals

We sought to gain a better understanding of the relationship between epilepsy and sleep quality and daytime sleepiness by performing a literature search of PubMed for case-control studies that compared patients with epilepsy to controls and reported the Pittsburgh sleep quality index (PSQI) and/or the Epworth sleepiness scale (ESS). Study-specific mean differences in the PSQI and ESS between cases and controls were extracted from the publications and pooled using random-effects meta-analysis. Twenty-five studies (2964 cases, 5232 controls) were included. Fifteen studies reported the PSQI and 24 the ESS. Mean age was 40 years; 50.4% were women. When comparing cases to controls, the pooled mean differences in the PSQI and ESS were 1.27 (95% confidence interval (CI): 0.76, 1.78; P < 0.001; I²: 81.4%) and 0.38 (95% CI: -0.07, 0.84; P = 0.099; I²: 81.0%). Subgroup analyses revealed that mean differences in the ESS were significantly lower in studies with a higher proportion of patients with focal epilepsy (P = 0.004). In this large-scale meta-analysis patients with epilepsy had a higher PSQI, close to the pathological cut-off, compared to controls, but a similar and unremarkable ESS. Further studies are needed to investigate potential effect modifiers, such as specific antiepileptic drugs or seizure frequency.

Bidirectional relationships of sleep and epilepsy in adults with epilepsy

This targeted review addresses the best accepted and most intriguing recent observations on the complex relationships between sleep and epilepsy. Ten to 15% of all epilepsies are sleep-related. Included in these is sleep-related hypermotor epilepsy, renamed from nocturnal frontal lobe epilepsy by a 2016 consensus conference since 30% of cases are extra-frontal, seizures are related to sleep rather than clock time, and the predominant semiology is hypermotor. Stereo-EEG is providing crucial insights into network activation in sleep-related epilepsies and definition of the epileptogenic zone. Pathologic high-frequency oscillations, a promising biomarker for identifying the epileptogenic zone, are most frequent in NREM sleep, lowest in wakefulness and REM sleep, similar to interictal epileptiform discharges (IEDs). Most sleep-related seizures are followed by awakening or arousal and IEDs cause arousals and increase after arousals, likely contributing to sleep/wake complaints. Sleep/wake disorders are 2-3 times more common in adults with epilepsy than the general population; these comorbidities are associated with poorer quality of life and may impact seizure control. Treatment of sleep apnea reduces seizures in many cases. An emerging area of research is in circadian biology and epilepsy. Over 90% of people with epilepsy have seizures with circadian periodicity, in part related to sleep itself, and the majority of SUDEP cases occur in sleep. Recognizing these bidirectional relationships is important for patient and caregiver education and counseling and optimizing epilepsy outcomes.

Prevalence of sleep disorders in patients with epilepsy: A questionnaire-based cross-sectional study

BACKGROUND

Sleep disturbance is a frequent finding in patients with epilepsy. As evaluation of sleep disorders and quality of sleep in patients with epilepsy may provide better management of these patients, we aimed to assess the prevalence of common sleep disorders in patients with epilepsy.

METHODS

Patients with epilepsy referred to an outpatient epilepsy clinic in Tehran during one year were included. Validated Persian questionnaires were used by an interviewer to assess Excessive daytime sleepiness (EDS), Restless leg syndrome (RLS), and insomnia. Also, patients' demographic features and clinical seizure-related characteristics were recorded.

RESULTS

Seventy patients (35 males) aged between 18 and 75 were enrolled. Among patients, 61.4, 35.7, and 28.6% suffered from insomnia, EDS, and RLS, respectively (mild to severe). When considering seizure characteristics, there was no significant correlation between either seizure frequency or its type and the prevalence of sleep disturbance (although sleep disturbance was more common among patients with higher seizure frequency and patients with generalized seizure). Interestingly, age had a positive correlation with EDS.

CONCLUSION

This study showed that sleep disturbance is a common finding in patients with epilepsy, which may become severe in some cases. Taking this into consideration, we suggest that routine evaluation of sleep disorders may help physicians to boost patients' sleep quality.

[Sleep and wake disorders in epilepsy]

OBJECTIVE

To summarize published data on the prevalence, characteristics and diagnostic criteria of sleep disorders in epilepsy.

MATERIAL AND METHODS

A search of published articles was performed in Medline (Pubmed), Scopus, Web of Science and e-library databases.

RESULTS

Epidemiologic, clinical and diagnostic aspects of excessive daytime sleepiness, obstructive sleep apnea and central apnea, restless leg syndrome and parasomnias related to slow-wave and REM-sleep in patients with epilepsy were analyzed.

CONCLUSIONS

Further studies are needed to gain an insight into the complex associations of sleep disorders in epilepsy to optimize diagnostic and treatment approaches and to improve the quality of life in that patient population.

Subjective and objective hypersomnia highly prevalent in adults with epilepsy

INTRODUCTION

Sleepiness is among the most common complaints of people with epilepsy, but objective documentation is lacking. We systematically investigated subjective and objective sleepiness in an observational cross-sectional cohort of adults with epilepsy (AWE).

METHODS

This is a prospective study of AWE consecutively recruited without foreknowledge of sleep/wake complaints. Polysomnography (PSG) with 18-channel electroencephalography (EEG) followed by multiple sleep latency testing (MSLT) was performed. Patients completed the Epworth Sleepiness Scale (ESS), a single-item question assessing excessive daytime sleepiness (EDS), and a 7-day sleep and seizure diary. Multivariable linear models were used to assess the association between MSLT mean sleep latency (MSL) and interests with adjustment of covariates of interest. Receiver operating characteristics (ROC) analysis was performed to evaluate the discrimination capability of ESS on MSL < 8 min and <5 min and investigate the optimal cutpoints.

RESULTS

Among 127 AWE (mean age: 38.7 ± 13.7 years), abnormal MSL (<8 min) was observed in 49.6% and MSL <5 min in 31.5%. While 78% reported feeling sleepy during the day on a single-item question, only 24% had elevated scores on the ESS (>10/24). The ESS score was associated with MSL even after adjusting for seizure frequency, antiseizure medication (ASM) standardized dose and number, age, gender, depression and insomnia symptom severity, and apnea-hypopnea index (HPI) and total sleep time on PSG (coefficients [95% confidence interval (CI)]: -0.26 [-0.48, -0.05], p = 0.018). The area under the curve (AUC) of the ESS ROC predicting MSL < 8 min and MSL < 5 min were similar: 0.62 (95%CI: 0.52-0.72) and 0.62 (95%CI: 0.51-0.74).

CONCLUSIONS

This is the largest prospective cross-sectional observational study to date using MSLT in AWE. We found subjective and objective daytime sleepiness highly prevalent in AWE and not explained by seizure frequency, ASM burden, symptoms of insomnia/depression, or PSG findings although those with MSL < 5 min were more likely to have obstructive sleep apnea (OSA). Pathologic sleepiness with MSL < 8 min was present in half of AWE. Nearly one-third of AWE unselected for sleep/wake complaints had MSL < 5 min, a range typical of narcolepsy.

Impaired vigilance networks in temporal lobe epilepsy: Mechanisms and clinical implications

Mesial temporal lobe epilepsy (mTLE) is a neurological disorder in which patients suffer from frequent consciousness-impairing seizures, broad neurocognitive deficits, and diminished quality of life. Although seizures in mTLE originate focally in the hippocampus or amygdala, mTLE patients demonstrate cognitive deficits that extend beyond temporal lobe function-such as decline in executive function, cognitive processing speed, and attention-as well as diffuse decreases in neocortical metabolism and functional connectivity. Given prior observations that mTLE patients exhibit impairments in vigilance, and that seizures may disrupt the activity and long-range connectivity of subcortical brain structures involved in vigilance regulation, we propose that subcortical activating networks underlying vigilance play a critical role in mediating the widespread neural and cognitive effects of focal mTLE. Here, we review evidence for impaired vigilance in mTLE, examine clinical implications and potential network underpinnings, and suggest neuroimaging strategies for determining the relationship between vigilance, brain connectivity, and neurocognition in patients and healthy controls.

Co-morbid sleep disorders and epilepsy: A narrative review and case examples

Co-morbid sleep disorders, including sleep apnea, insomnia, restless legs syndrome, and the parasomnias, occur frequently in people with epilepsy. This article reviews the cardinal presenting symptoms and diagnostic features of each of these disorders to enable epileptologists to readily screen and identify sleep co-morbidities in their patients. It summarizes current evidence concerning the reciprocal relationship between sleep disturbances and epilepsy and available treatment options for common sleep disorders in people with epilepsy. Several illustrative cases demonstrate the practical consequences of co-morbid sleep disorders in epilepsy patients and suggest diagnostic and treatment approaches that may improve daytime functioning, alertness, quality of life, and seizure burden.