Sleep and Epilepsy

The Reciprocal Relationship between Sleep and Epilepsy

The relationship between sleep and epilepsy is bidirectional. Certain epilepsy syndromes predominantly or exclusively manifest during sleep, with seizures frequently originating from non-rapid eye movement (NREM) sleep. Interictal epileptiform discharges observed on electroencephalograms are most likely to be activated during the deep NREM sleep stage known as N3. Conversely, epileptiform discharges, anti-seizure medications (ASMs), as well as other anti-seizure therapies can exert detrimental effects on sleep architecture. Moreover, the co-occurrence of sleep disorders has the potential to exacerbate seizure control. Understating the relationship between sleep and epilepsy is crucial for healthcare providers. Addressing and managing sleep-related problems in individuals with epilepsy can potentially contribute to improved seizure control and overall well-being. At the same time, improving seizure control can improve sleep quality and quantity, thus further improving the health of individuals with epilepsy.

On the relationships between epilepsy, sleep, and Alzheimer's disease: A narrative review

Epilepsy, sleep, and Alzheimer's disease (AD) are tightly and potentially causally interconnected. The aim of our review was to investigate current research directions on these relationships. Our hope is that they may indicate preventive measures and new treatment options for early neurodegeneration. We included articles that assessed all three topics and were published during the last ten years. We found that this literature corroborates connections on various pathophysiological levels, including sleep-stage-related epileptiform activity in AD, the negative consequences of different sleep disorders on epilepsy and cognition, common biochemical pathways as well as network dysfunctions. Here we provide a detailed overview of these topics and we discuss promising diagnostic and therapeutic consequences.

Evaluation of Sleep Disturbances in Patients with Nocturnal Epileptic Seizures in a Romanian Cross-Sectional Study

(1) Background: Based on the premise that epilepsy is frequently associated with hypnopathies, in this study we aim to analyze the prevalence of sleep disturbances among patients with epilepsy, with exclusively or predominantly nocturnal seizures, in relation to demographic factors as well as clinical and electroencephalography (EEG) aspects. (2) Methods: 69 patients with nocturnal epilepsy were included in our study. Sleep disturbances were measured with the Pittsburgh Sleep Quality Index (PSQI) questionnaire, followed by a long-term video-EEG monitoring during sleep. We analyzed the PSQI results in relation to patients' gender and age and determined the correlations between the PSQI scores and the modifications on video-EEG recordings, in comparison to a control group of 25 patients with epilepsy but without nocturnal seizures. (3) Results: We found a statistically significant difference between the PSQI of patients with nocturnal seizures compared to those without nocturnal epileptic manifestations. In the experimental group, the mean PSQI score was 7.36 ± 3.91 versus 5.04 ± 2.56 in controls. In women, the average PSQI score was 8.26, whilst in men it only reached 6.41, highlighting a statistically significant difference between genders (p ˂ 0.01). By examining the relationships between the PSQI scores and certain sleep-related factors, evidenced on the nocturnal video-EEG, we found a statistically significant difference between PSQI values of patients who reached the N2 stage, and those who reached the N3 stage of nonrapid eye movement (NREM) sleep, highlighting that those with a more superficial nocturnal sleep also had higher PSQI scores. There were no statistically significant differences regarding the PSQI scores between patients with or without interictal epileptiform discharges, and also in the few patients with nocturnal seizures where we captured ictal activity. (4) Conclusions: we evidenced in this study a poor quality of sleep in patients with nocturnal epilepsy, mostly in women, independent of age. We observed that sleep disturbances were due to superficial and fragmented sleep with frequent microarousals, not necessarily caused by the electrical epileptiform activity.

The abrupt shift to slower frequencies after arousal from sleep in healthy young adults

STUDY OBJECTIVES

Post-arousal hypersynchrony (PAH) is an atypical arousal pattern in children's electroencephalography. PAH is an abrupt shift to slower frequencies in arousal-related responses, appearing as slow-wave clusters. In contrast, the prevalence of PAH in healthy young adults is still unknown. Here, we examined the prevalence and characteristics of PAH in healthy young participants.

METHODS

Thirty healthy young participants underwent one night of polysomnography (thirteen females, 22.8 ± 2.0 years [mean ± standard deviation]). We examined the prevalence of PAH as a function of sleep stage, sleep cycle, and time course (the first or the second half). The correlation between PAH and sleep variables was examined. The %N3 was compared for each sleep cycle and time course.

RESULTS

Twenty-eight out of 30 participants exhibited PAH (4.6 ± 4.8 times per night). PAH increased significantly during the first sleep cycle and the first half-sleep period. It was observed only in non-rapid eye movement (NREM) and not in REM sleep. The number of PAHs correlated with the number of arousals and arousal indices. The %N3 increased in the first half-sleep and the first sleep cycle.

CONCLUSIONS

PAH was relatively common in healthy young participants. Since PAH occurred in a state with a high prevalence of %N3, the first sleep cycle, or the first half-sleep, we suggest that PAH may be affected by the sleep homeostasis process. Since PAH occurred only in NREM sleep and correlated with arousal increment, it may have the function of suppressing NREM sleep's cortical arousal.

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.

Metabolic syndrome and obstructive sleep apnea syndrome among patients with epilepsy on monotherapy

OBJECTIVES

The study aimed to determine the frequency of metabolic syndrome (MetS) and obstructive sleep apnea syndrome (OSAS) in patients with epilepsy receiving monotherapy and the relationship between these syndromes and antiepileptic drugs (AEDs).

METHODS

Two hundred and ninety-seven patients with epilepsy between the ages of 18-65 years receiving monotherapy for at least one year and 50 healthy participants were enrolled. Body mass indices and waist circumferences were measured. Serum fasting glucose levels, high-density lipoprotein (HDL), low density lipoprotein (LDL), total cholesterol (TC), triglyceride, and serum AED concentrations were noted. The frequency of MetS in patients with epilepsy was calculated. The snoring, tiredness, observed apnea, high blood pressure, body mass index, age, neck circumference, and male gender (STOP-Bang) questionnaire was used to determine the risk of OSAS. The relationship between these two syndromes and seizure type, disease duration, AED dosage, and treatment duration was analyzed.

RESULTS

Metabolic syndrome was more frequent in patients with epilepsy compared with healthy participants (32.6% vs. 12.0%), and it was diagnosed in 37.8% of patients receiving valproic acid (VPA), 36.1% of patients receiving carbamazepine (CBZ), 34.9% of patients receiving oxcarbazepine (OXC), and 30.5% of patients on levetiracetam (LEV). There was a positive correlation between VPA treatment duration and MetS existence (p < 0.05). However, MetS frequency did not change because of seizure type, disease duration, or AED dosages in patients with epilepsy receiving monotherapy. The risk for OSAS was higher in patients with epilepsy compared with healthy participants (24.6% vs. 12%), and it was calculated high in 27.7% of patients receiving CBZ, 32.2% of patients receiving LEV, and 30.2% of patients receiving OXC. The OSAS risk was higher in patients who have focal seizures than generalized seizures (p = 0.044). There was no relationship between OSAS risk and duration of epilepsy, duration of treatment, drug doses, and serum drug levels (p > 0.05).

CONCLUSION

Higher frequency of MetS and OSAS risk should be kept in mind on clinical follow-up of patients with epilepsy receiving monotherapy.

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.

Comorbid Sleep Disturbances in Neurologic Disorders

PURPOSE OF REVIEW

This article provides a review of disturbances of sleep comorbid with common neurologic disorders.

RECENT FINDINGS

A wide variety of neurologic disorders are frequently complicated by comorbid sleep disturbances. In many cases, a bidirectional relationship appears to occur between sleep function and the neurologic disease, such that treatment of comorbid sleep disturbances may improve the symptoms of the neurologic disease.

SUMMARY

Neurologic disorders are often associated with abnormalities of sleep. Sleep influences the severity of both epilepsy and headache, and treatment of comorbid sleep disorders may improve seizure and headache frequency. Alzheimer disease is characterized by circadian phase delay and poor nighttime sleep and is strongly associated with obstructive sleep apnea. Parkinson disease is associated with several sleep disorders, including insomnia, restless legs syndrome, rapid eye movement (REM) sleep behavior disorder, daytime hypersomnia, and sleep-disordered breathing. Hypoventilation in amyotrophic lateral sclerosis and other neuromuscular disorders often presents initially with sleep problems, and treatment with noninvasive ventilation improves survival and quality of life.

Comparing sleep profiles between patients with juvenile myoclonic epilepsy and symptomatic partial epilepsy: Sleep questionnaire-based study

OBJECTIVES

Patients with epilepsy commonly report excessive daytime sleepiness and daytime fatigue, which may be attributed to the direct effect of seizures, a side effect of antiepileptic drugs or a combination of the two. The aim of the study was to compare sleep profiles in patients with juvenile myoclonic epilepsy (JME) and symptomatic partial epilepsy (PE) in drug naïve and treated patients using standardized sleep questionnaires.

METHODS

Three study groups: - 1) juvenile myoclonic epilepsy (N=40) [drug naïve (N=20); On sodium valproate (SVA) (N=20)]; 2) symptomatic partial epilepsy (N=40) [drug naïve (N=20); On carbamazepine (CBZ) (N=20)]; 3) healthy controls (N=40) completed 3 standardized sleep questionnaires - Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, and NIMHANS Comprehensive Sleep Disorders Questionnaire. Scores were compared using t-test and Chi-squared tests (P≤0.005).

RESULTS

The mean PSQI scores as well as the proportion of subjects with abnormal PSQI scores were higher in patients with JME and PE compared to controls. Although the mean ESS scores were comparable between patients with epilepsy and controls, the percentage of patients with partial epilepsy having abnormal ESS scores was higher. No significant differences were present between drug naïve and treatment monotherapy groups. Excessive daytime somnolence was reported more often by patients with JME compared to patients with partial epilepsy and controls.

CONCLUSION

This study found that patients with epilepsy have a higher prevalence of poor sleep quality compared to controls. Moreover, a significantly higher percentage of patients with partial epilepsy had higher ESS scores compared to healthy controls. However, there was no difference between ESS and PSQI scores between drug naïve and treated patients with JME or PE.

SIGNIFICANCE

Poor sleep quality is more prevalent in patients with epilepsy irrespective of the use of antiepileptic medications. Excessive daytime somnolence is more commonly seen in patients with partial epilepsy when compared to the general population.

How do people with drug-resistant mesial temporal lobe epilepsy sleep? A clinical and video-EEG with EOG and submental EMG for sleep staging study

This study aimed to assess subjective and objective sleep parameters in a homogeneous group of drug-resistant mesial temporal lobe epilepsy (MTLE) patients through internationally validated clinical questionnaires, video-electroencephalographic (VEEG) and polysomnographic (PSG) studies. Fifty-six patients with definite diagnosis of MTLE who were candidates for epilepsy surgery underwent a detailed clinical history, the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Stanford Sleepiness Scale (SSS), neurological examination, 1.5 T brain magnetic resonance imaging, VEEG and PSG. Sixteen percent of patients reported significant daytime sleepiness as measured by ESS and 27% reported low levels of sleep quality as measured by PSQI. Patients with medically resistant epilepsy by MTLE showed increased wakefulness after sleep onset (WASO) with mean ± standard deviation of 17.4 ± 15.6, longer non-rapid eye movement (NREM) 1 (7.5 ± 4.6%) and NREM3 sleep (26.6 ± 11.8%), abnormal rapid eye movement (REM) latency in 30/56 patients, shorter REM sleep (16.7 ± 6.6%), and abnormal alpha delta patterns were observed in 41/56 patients. The analysis of interictal epileptic discharges (IEDs) evidenced highest spiking rate during NREM3 sleep and higher concordance with imaging data when IEDs were recorded in sleep, mainly during REM sleep. We concluded that patients with MTLE showed disrupted sleep architecture that may result in daytime dysfunction and sleep complaints. Furthermore, NREM sleep activated focal IEDs and them - when recorded during sleep - had higher localizing value.

Impact of mood stabilizers and antiepileptic drugs on cytokine production in-vitro

Changes within the immune system have been reported to contribute to the pathophysiology of bipolar disorder and epilepsy. Interestingly, overlapping results regarding the cytokine system have been found for both diseases, namely alterations of interleukins IL-1β, IL-2, IL-4, IL-6, and tumor necrosis factor-α (TNF-α). However, the effect of mood stabilizers and antiepileptic drugs (AEDs) on these cytokines has not been systematically evaluated, and their effect on IL-17 and IL-22, other immunologically important cytokines, has not been reported. Therefore, we systematically measured levels of IL-1β, IL-2, IL-4, IL-6, IL-17, IL-22 and TNF-α in stimulated blood of 14 healthy female subjects in a whole blood assay using the toxic shock syndrome toxin TSST-1 as stimulant. Blood was supplemented with the mood stabilizers or antiepileptic drugs primidone (PRM), carbamazepine (CBZ), levetiracetam (LEV), lamotrigine (LTG), valproic acid (VPA), oxcarbazepine (OXC), topiramate (TPM), phenobarbital (PB), lithium, or no drug. IL-1β production was significantly decreased by PRM, CBZ, LEV, LTG, OXC, PB and lithium. IL-2 significantly decreased by PRM, CBZ, LEV, LTG, VPA, OXC, TPM and PB. IL-22 significantly increased by PRM, CBZ, LEV, OXC, TPM and lithium and decreased by VPA. TNF-α production significantly decreased under all applied drugs. The mechanism of action and side effects of mood stabilizers and AEDs may involve modulation of IL-1β, IL-2, IL-22 and TNF-α signaling pathways. IL-22 may be a research target for specific therapeutic effects of mood stabilizers and AEDs. These drugs might influence cytokine production by modulating ion channels and γ-aminobutyric acid (GABA) receptors of immune cells.

Screening for sleep dysfunction after traumatic brain injury

Numerous studies on the high prevalence of sleep disorders in individuals with traumatic brain injury (TBI) have been conducted in the past few decades. These disorders can accentuate other consequences of TBI, negatively impacting mood, exacerbating pain, heightening irritability, and diminishing cognitive abilities and the potential for recovery. Nevertheless, sleep is not routinely assessed in this population. In our review, we examined the selective screening criteria and the scientific evidence regarding screening for post-TBI sleep disorders to identify gaps in our knowledge that are in need of resolution. We retrieved papers written in the English-language literature before June 2012 pertinent to the discussion on sleep after TBI found through a PubMed search. Within our research, we found that sleep dysfunction is highly burdensome after TBI, treatment interventions for some sleep disorders result in favorable outcomes, sensitive and specific tests to detect sleep disorders are available, and the cost-effectiveness and sustainability of screening have been determined from other populations. The evidence we reviewed supports screening for post-TBI sleep dysfunction. This approach could improve the outcomes and reduce the risks for post-TBI adverse health and nonhealth effects (e.g., secondary injuries). A joint sleep and brain injury collaboration focusing on outcomes is needed to improve our knowledge.