The influence of carbamazepine on sleep-EEG and the clonidine test in healthy subjects: results of a preliminary study

Effects of anti-seizure therapies on sleep in patients with epilepsy: A literature review

Sleep disorder is common in epilepsy. With a recent rapid development in sleep medicine, it has been increasingly recognized that anti-seizure therapies, either anti-seizure medications (ASMs) or non-pharmaceutical approaches, can take direct or indirect influence on sleep in patients with epilepsy. Here, we systematically review the effect of anti-seizure treatments on sleep. ASMs targeting at different sites exerted various effects on both sleep structure and sleep quality. Non-pharmaceutical treatments including resective surgery, ketogenic diet, and transcranial magnetic stimulation appear to have a positive effect on sleep, while vagus nerve stimulation, deep brain stimulation, and brain-responsive neurostimulation are likely to interrupt sleep and exacerbate sleep-disordered breathing. The potential mechanisms underlying how non-pharmacological approaches affect sleep are also discussed. The limitation of most studies is that they were largely based on small cohorts by short-term observations. Further well-designed and large-scale investigations in this field are warranted. Understanding the effect of anti-seizure therapies on sleep can guide clinicians to optimize epilepsy treatment in the future.

Headache, drugs and sleep

Background

Headache and sleep mechanisms share multiple levels of physiological interaction. Pharmacological treatment of headache syndromes may be associated with a broad range of sleep disturbances, either as a direct result of the pharmacology of the drug used, or by unmasking physiological alterations in sleep propensity seen as part of the headache symptom complex.

Purpose

This review summarises known sleep and circadian effects of various drugs commonly used in the management of headache disorders, with particular attention paid to abnormal sleep function emerging as a result of treatment.

Method

Literature searches were performed using MEDLINE, PubMed, and the Cochrane database using search terms and strings relating to generic drug names of commonly used compounds in the treatment of headache and their effect on sleep in humans with review of additional pre-clinical evidence where theoretically appropriate.

Conclusions

Medications used to treat headache disorders may have a considerable impact on sleep physiology. However, greater attention is needed to characterise the direction of the changes of these effects on sleep, particularly to avoid exacerbating detrimental sleep complaints, but also to potentially capitalise on homeostatically useful properties of sleep which may reduce the individual burden of headache disorders on patients.

Sleep and epilepsy

The intimate relationship between sleep and epilepsy has long been recognized, yet our understanding of the relationship is incomplete. In this article we address four key issues in this area. First, we consider the reciprocal interaction between sleep and epilepsy. Sleep state clearly influences seizure onset, particularly in certain epilepsy syndromes. The converse is also true; epilepsy may disrupt sleep, either directly through seizures and epileptiform activity, or indirectly through medication-related effects. Unraveling the influences of sleep stage, epilepsy syndrome, and drug effects is challenging, and the current state of knowledge is reviewed. Secondly, accurate diagnosis of sleep-related epilepsy can be difficult, particularly the distinction of nocturnal frontal lobe epilepsy (NFLE) from arousal parasomnias. The challenges in this area, along with work from the authors, are discussed. Thirdly, we will explore the putative relationship between obstructive sleep apnea (OSA) and epilepsy, including the effect of OSA on quality of life; this will lead us to a brief exploration of the effects of OSA on neuroendocrine function. Finally, we will review the evidence surrounding the role of sleep in sudden unexpected death in epilepsy (SUDEP).

[Disturbances of slow-wave sleep and psychiatric disorders]

Slow-wave sleep is defined as sleep stages 3 and 4 that characteristically show slow delta EEG activity during polysomnography. The percentage of slow-wave sleep normally declines with age. Sleep disorders are a common symptom of many psychiatric disorders. In polysomnographic recordings they mostly manifest as disturbances of sleep continuity. In some disorders changes in REM sleep are also found. A reduction of slow-wave sleep has most often been described in patients with depression and addictive disorders. More recent research implicates slow-wave sleep as an important factor in memory consolidation, especially the contents of declarative memory. Psychotropic drugs influence sleep in different ways. Hypnotic substances can reduce the deep sleep stages (e.g. benzodiazepines), whereas 5-HT2C antagonists increase the percentage of slow-wave sleep. Whether a selective impairment/alteration of slow-wave sleep is clinically relevant has not yet been proved.

Sleep in adults with attention deficit hyperactivity disorder (ADHD) before and during treatment with methylphenidate: a controlled polysomnographic study

STUDY OBJECTIVES

Sleep problems are frequently associated with childhood ADHD, as indicated by numerous polysomnographic investigations showing increased nocturnal movements, reduced sleep efficiency, and decreased percentage of REM sleep (although findings are not consistent over all studies). Data on objective and subjective sleep parameters in adults with ADHD are sparse, and to date the impact of stimulants, the most widely used pharmacological treatment for ADHD, on sleep in adults with ADHD has not been examined. Thus the objectives of our study were to assess objective and subjective sleep parameters in adults with ADHD and the impact of stimulant medication on sleep.

DESIGN

Two-group comparison and open-label therapy study.

PARTICIPANTS

We enrolled 34 nonmedicated patients with ADHD, of whom 24 were without current comorbid psychiatric disorders, and 34 sex- and gender-matched control subjects without current psychiatric disorders or psychotropic medication.

INTERVENTIONS

Ten patients were treated with methylphenidate over > or =26 days with a mean daily dose of 36.7 +/- 11.2 mg.

MEASUREMENTS

Polysomnographic recording over 2 consecutive nights as well as assessments of subjective sleep parameters were performed in all patients and controls before treatment and reassessed in those patients receiving methylphenidate.

RESULTS

Compared to controls untreated patients showed increased nocturnal activity, reduced sleep efficiency, more nocturnal awakenings and reduced percentage of REM sleep. Treatment with methylphenidate resulted in increased sleep efficiency as well as a subjective feeling of improved restorative value of sleep.

CONCLUSIONS

Sleep problems in patients with ADHD continue from childhood to adulthood, with similar objective sleep characteristics in adults and children with ADHD. Medication with methylphenidate appears to have beneficial effects on sleep parameters in adults with ADHD.

Sleep and circadian rhythms in children and adolescents with bipolar disorder

The aim of this paper is to highlight the importance of the sleep-wake cycle in children and adolescents with bipolar disorder. After presenting an overview of the measurement and function of human sleep, we describe changes in sleep and circadian functioning across the life cycle. We then review evidence that, in adults, sleep and/or circadian rhythms are of considerable influence in the multifactorial causal chain implicated in relapse in bipolar disorder, discussing relevant mechanisms. The latter include abnormalities in the amount and timing of sleep, the role of social zeitgebers, and the importance of sleep in regulating emotional responses and mood. We next present preliminary data indicating considerable sleep disturbance among children and adolescents with bipolar disorder. Given the considerable sleep disturbance evident among children and adolescents with bipolar disorder along with a key role for sleep in emotion regulation and learning, we conclude that sleep among children and adolescents with bipolar disorder is a critical domain for future research. An agenda for future research is presented that includes descriptive studies, investigations of causality, and treatment development research.

Sleep and epilepsy: what we know, don't know, and need to know

Long-term video-EEG and, more recently, video-polysomnography, have provided the means to confirm and expand on the interconnections between sleep and epilepsy. Some of these relationships have become firmly established. When one of the authors (N.F.S.) presented part of this paper at a symposium on the Future of Sleep in Neurology at an American Clinical Neurophysiology Society annual meeting in 2004, the purpose was to summarize what we know, don't know, and need to know about the effects of sleep on epilepsy and epilepsy on sleep. Here we seek to summarize some of the more firmly established relationships between sleep and epilepsy and identify intriguing associations that require further elucidation.

Effects of antiepileptic drugs on sleep structure : are all drugs equal?

Good-quality sleep is an important and frequently overlooked component of general health, but it is particularly essential to patients with epilepsy. Their sleep can be affected by seizures, concurrent sleep disorders and seizure treatment. Worsening sleep can result not only in poor daytime functioning but also potentially in worsening epilepsy. The effects of antiepileptic drugs (AEDs) on sleep are of particular concern. Some agents have detrimental effects on sleep, particularly benzodiazepines and barbiturates but also phenytoin and, possibly, carbamazepine. Others, especially gabapentin, seem to actually improve sleep quality. Much research in this area is confounded by the effects of seizures and concurrent conditions on sleep, making it difficult to isolate the direct effects of AEDs on sleep. But because AEDs have independent effects on sleep quality, the choice of an appropriate agent not only determines whether seizures are completely controlled but also whether the patient performs optimally on a daily basis.

Sleep complaints and epilepsy: the role of seizures, antiepileptic drugs and sleep disorders

Patients with epilepsy commonly complain of daytime sleepiness and poor sleep quality. These problems are frequently attributed to antiepileptic drugs and seizures. Antiepileptic drugs and seizures have effects on sleep architecture often leading to daytime sleepiness. However, sleep symptoms may also be caused by poor sleep hygiene and primary sleep disorders. Primary sleep disorders should be suspected in patients with persistent daytime sleepiness, particularly those on AED monotherapy or with low serum drug concentrations and well-controlled seizures. Treatment of sleep disorders and improved sleep hygiene may improve seizure control and quality of life.

The effects of levetiracetam on objective and subjective sleep parameters in healthy volunteers and patients with partial epilepsy

Levetiracetam is a novel antiepileptic drug which has recently been released as an adjunctive treatment for partial epilepsy. In the two studies reported here we examined the objective and subjective effects of levetiracetam on sleep in 12 healthy volunteers and 17 patients [16 who could be evaluated for electroencephalogram (EEG) recordings] with a history of partial epilepsy on stable carbamazepine monotherapy. The studies were of a similar double-blind crossover placebo-controlled design with subjects' sleep being recorded in their own homes. The results from the two studies showed considerable similarities. In both, levetiracetam produced an increase in the time spent in stage 2 sleep, which in the patient study was accompanied by a decrease in the time spent in stage 4 sleep and in the volunteer study an increase in rapid eye movement (REM) latency. The subjective changes included reports that sleep was of a better quality with fewer awakenings and patients also reported that their sleep was more restful. Volunteers and patients did, however, feel less alert on waking in the morning. Therefore, both groups reported a decrease in awakenings after levetiracetam despite the finding from the EEG of no change in the actual number of awakenings. It may be concluded from both studies that levetiracetam does affect some indicators of subjective sleep perception, but does not influence objective sleep measures of sleep continuity. The results from the patient study during placebo add-on treatment also showed that patients on carbamazepine had a marked increase in SWS, an increase in stage 2 sleep and an increase in REM latency compared with healthy volunteers. Interestingly, levetiracetam also reduced bilateral epileptiform EEG activity, particularly in patients with more discharges.

Effects of carbamazepine on dexamethasone suppression and sleep electroencephalography in borderline personality disorder

The pathophysiology of borderline personality disorder (BPD) remains obscure, but there is mounting evidence of brain dysfunction without focal abnormality. The dexamethasone suppression test (DST) and sleep electroencephalography (sleep EEG) have been studied in BPD, but the findings seem to be related to a concomitant axis I diagnosis of major depression (MD) rather than to BPD itself. There is no effective treatment for BPD. Carbamazepine (CBZ) has shown contradictory results and in a previous study, our results were negative. In this study, we investigated the effects of CBZ versus placebo on the DST and sleep EEG in a sample of 20 BPD patients without concomitant MD. CBZ given at doses that are therapeutic for epilepsy and affective disorders may have an effect on the DST and sleep EEG in BPD. CBZ significantly increased the postdexamethasone plasma cortisol values. This did not parallel MD or an increase in the Hamilton depression rating scores. CBZ also increased slow wave sleep (SWS). The mechanisms by which CBZ increased postdexamethasone plasma cortisol levels and SWS in BPD are discussed.

Sleep and depression--results from psychobiological studies: an overview

Disturbances of sleep are typical for most depressed patients and belong to the core symptoms of the disorder. Polysomnographic sleep research has demonstrated that besides disturbances of sleep continuity, in depression sleep is characterized by a reduction of slow wave sleep and a disinhibition of REM sleep, with a shortening of REM latency, a prolongation of the first REM period and increased REM density. These findings have stimulated many sleep studies in depressive patients and patients with other psychiatric disorders. In the meantime, several theoretical models, originating from basic research, have been developed to explain sleep abnormalities of depression, like the two-process-model of sleep and sleep regulation, the GRF/CRF imbalance model and the reciprocal interaction model of non-REM and REM sleep regulation. Interestingly, most of the effective antidepressant agents suppress REM sleep. Furthermore, manipulations of the sleep-wake cycle, like sleep deprivation or a phase advance of the sleep period, alleviate depressive symptoms. These data indicate a strong bi-directional relationship between sleep, sleep alterations and depression.

Interactions between sleep and epilepsy

Sleep is one of the best-documented factors influencing the expression of seizures and interictal discharges. Janz studied the relation between seizures and the sleep/wake cycle and divided the epilepsies into three categories: nocturnal, awakening, and diffuse. Since then, the effect of sleep on the ictal and interictal manifestations of epilepsy has been studied extensively. Many seizures are activated by sleep or arousal from sleep. Interictal discharges are also seen more commonly during sleep, with the greatest activation seen during nonrapid eye movement sleep. Sleep not only increases the frequency of epileptiform abnormalities, but also may alter their morphology and distribution. Sleep deprivation also facilitates both epileptiform abnormalities and seizures. Seizures, on the other hand, also impact sleep. Epileptic patients demonstrate multiple sleep abnormalities, including an increased sleep latency, fragmented sleep, increased awakenings and stage shifts, and an increase in stages 1 and 2 of nonrapid eye movement sleep. These disturbances may in turn be modulated by antiepileptic treatment. This review summarizes the interactions between sleep and epilepsy, including the timing of seizures during the sleep/wake cycle, the influence of sleep on various seizure disorders, the effects of sleep deprivation, and the changes in sleep patterns caused by seizures and their treatment.

Effect of antiepileptic drugs on sleep

The interactions between sleep and epilepsy are well known. A nodal point of the relationship between sleep and epilepsy is represented by pharmacological treatment. Sleep disturbances such as drowsiness are among the most frequent side effects of treatment with antiepileptic drugs, since they can deeply modify both sleep architecture and the sleep-wake cycle. Severe daytime somnolence affects patients' activities and it may facilitate the occurrence of seizures. These considerations underline the importance of antiepileptic drugs having anticonvulsant properties that do not negatively influence sleep and daytime somnolence. In this paper we review some relevant aspects of the effects of antiepileptic drugs on sleep.

Nocturnal sleep and daytime somnolence in untreated patients with temporal lobe epilepsy: changes after treatment with controlled-release carbamazepine

PURPOSE

To define sleep disturbances in patients with temporal lobe epilepsy (TLE) and explore the association between carbamazepine (CBZ) therapy, sleep, and daytime somnolence.

METHODS

We recorded nocturnal polysomnography and measured subjective and objective daytime somnolence in a group of newly diagnosed TLE patients, who had no evidence of anatomic brain lesion on neuroimaging and had never been treated before. Recordings were performed at baseline, after the initial administration of 400 mg CBZ-controlled release (CR) and after 1 month of treatment (400 mg twice daily b.i.d.). The findings were compared with those of a group of young healthy volunteers, both at baseline and after the first administration of CBZ. The chronic effect of CBZ-CR treatment was evaluated only in TLE patients.

RESULTS

At baseline, nocturnal sleep patterns of TLE patients did not show marked alterations when the influence of seizures, cerebral lesions, and drugs had been ruled out. In both the TLE and the control groups, initiation of CBZ therapy provoked a reduction and a fragmentation of rapid eye movement (REM) sleep and an increase in the number of sleep stage shifts. In the TLE group, these effects were almost completely reversed after 1 month of treatment, and no significant difference was noted between baseline condition and long-term follow-up. With regard to daytime sleepiness, initial administration of the drug caused an increase in objective sleepiness only in the control group. Subjective sleepiness was higher in the control group than in the TLE group but was not modified by the drug.

CONCLUSIONS

We conclude that CBZ-CR has negative effects on REM sleep during initial administration but chronic treatment does not significantly modify nocturnal sleep or daytime somnolence.