Valproate for sleep consolidation in periodic limb movement disorder

Restless Legs Syndrome and Periodic Limb Movements of Sleep: From Neurophysiology to Clinical Practice

SUMMARY

This article summarizes restless legs syndrome (RLS), periodic limb movements of sleep, and periodic limb movement disorder. RLS is a common sleep disorder with a prevalence of 5% to 15% in the general population. RLS can present in childhood, and incidence increases with age. RLS can be idiopathic or secondary to iron deficiency, chronic renal failure, peripheral neuropathy, and medications such as antidepressants (with higher rates for mirtazapine and venlafaxine, while bupropion may reduce symptoms at least in the short term), dopamine antagonists (neuroleptic antipsychotic agents and antinausea medications), and possibly antihistamines. Management includes pharmacologic agents (dopaminergic agents, alpha-2 delta calcium channel ligands, opioids, benzodiazepines) and nonpharmacologic therapies (iron supplementation, behavioral management). Periodic limb movements of sleep are an electrophysiologic finding commonly accompanying RLS. On the other hand, most individuals with periodic limb movements of sleep do not have RLS. The clinical significance of the movements has been argued. Periodic limb movement disorder is a distinct sleep disorder that arises in individuals without RLS and is a diagnosis of exclusion.

A Narrative Review of the Lesser Known Medications for Treatment of Restless Legs Syndrome and Pathogenetic Implications for Their Use

Background

There are several well-known treatments for Restless Legs Syndrome (RLS), including dopamine agonists (pramipexole, ropinirole, rotigotine), anticonvulsants (gabapentin and its analogs, pregabalin), oral or intravenous iron, opioids and benzodiazepines. However, in clinical practice, treatment is sometimes limited due to incomplete response or side effects and it is necessary to be aware of other treatment options for RLS, which is the purpose of this review.

Methods

We performed a narrative review detailing all of the lesser known pharmacological treatment literature on RLS. The review purposefully excludes well-established, well-known treatments for RLS which are widely accepted as treatments for RLS in evidence-based reviews. We also have emphasized the pathogenetic implications for RLS of the successful use of these lesser known agents.

Results

Alternative pharmacological agents include clonidine which reduces adrenergic transmission, adenosinergic agents such as dipyridamole, glutamate AMPA receptor blocking agents such as perampanel, glutamate NMDA receptor blocking agents such as amantadine and ketamine, various anticonvulsants (carbamazepine/oxcarbazepine, lamotrigine, topiramate, valproic acid, levetiracetam), anti-inflammatory agents such as steroids, as well as cannabis. Bupropion is also a good choice for the treatment of co-existent depression in RLS because of its pro-dopaminergic properties.

Discussion

Clinicians should first follow evidence-based review recommendations for the treatment of RLS but when the clinical response is either incomplete or side effects are intolerable other options can be considered. We neither recommend nor discourage the use of these options, but leave it up to the clinician to make their own choices based upon the benefit and side effect profiles of each medication.

Summary

Clinicians should first follow evidence-based reviews for RLS but when response is incomplete and side effects intolerable, other medications can be considered. We do not make a recommendation on these options but leave it up to the clinician to make their own choice based upon the benefit and side effect profiles of each medication.

Valproate-induced enuresis: a prospective study

AIM

The aim of this study was to determine the frequency and characteristics of secondary enuresis in children initiated on valproate treatment.

METHOD

This was a prospective study conducted in children aged 5 to 12 years with suspected newly diagnosed epilepsy and maintained on valproate for at least 1 month. Adverse events spontaneously reported by parents were recorded at each follow-up visit. In addition, we specifically asked about enuresis and other side effects known to occur with valproate treatment. We assessed the frequency of enuresis and its association with a number of variables.

RESULTS

Seventy-two children (43 males and 29 females) with a mean age of 8 years 7 months (range 5-12y) were included in this study. Secondary enuresis developed in 17 (24%) of these children after, on average, 19.8 days of exposure to valproate. The data obtained from a multivariate analysis indicate that age was the only significant factor in predicting the development of enuresis. Enuresis ceased in all children after discontinuation of valproate use, and in 10 out of 11 children still on the drug.

INTERPRETATION

Secondary enuresis is a common adverse event associated with valproate use in children, which is not usually spontaneously reported and is reversible in most cases.

Periodic limb movements during sleep and their effect on the cardiovascular system: is there a final answer?

Periodic limb movements during sleep (PLMS) is a sleep-related movement disorder characterized by repetitive limb movements during sleep, seen predominantly in the legs but also occasionally involving the arms. These movements may be associated with arousals that can lead to increases in sympathetic tone, resulting in tachycardia and elevated systolic blood pressure. Chronic sustained tachycardia and elevated systolic blood pressure are known to be associated with the development of arrhythmias, hypertension, left ventricular hypertrophy, and congestive heart failure. However, the data are not entirely clear on whether untreated PLMS is associated with these cardiovascular risks. This review examines the current evidence on whether PLMS has any effect on the cardiovascular system.

The treatment of restless legs syndrome and periodic limb movement disorder in adults--an update for 2012: practice parameters with an evidence-based systematic review and meta-analyses: an American Academy of Sleep Medicine Clinical Practice Guideline

A systematic literature review and meta-analyses (where appropriate) were performed to update the previous AASM practice parameters on the treatments, both dopaminergic and other, of RLS and PLMD. A considerable amount of literature has been published since these previous reviews were performed, necessitating an update of the corresponding practice parameters. Therapies with a STANDARD level of recommendation include pramipexole and ropinirole. Therapies with a GUIDELINE level of recommendation include levodopa with dopa decarboxylase inhibitor, opioids, gabapentin enacarbil, and cabergoline (which has additional caveats for use). Therapies with an OPTION level of recommendation include carbamazepine, gabapentin, pregabalin, clonidine, and for patients with low ferritin levels, iron supplementation. The committee recommends a STANDARD AGAINST the use of pergolide because of the risks of heart valve damage. Therapies for RLS secondary to ESRD, neuropathy, and superficial venous insufficiency are discussed. Lastly, therapies for PLMD are reviewed. However, it should be mentioned that because PLMD therapy typically mimics RLS therapy, the primary focus of this review is therapy for idiopathic RLS.

[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.

Effects of valproic acid on sleep in children with epilepsy

PURPOSE

Parents frequently report increased sleep duration in their children during treatment with valproic acid (VPA). We assessed sleep duration and sleep behavior before and after tapering VPA in children treated for more than 6 months.

METHODS

Sleep variables were assessed by questionnaire, diary, and actigraphy (for 7 consecutive days and nights) before and 8-12 weeks after termination of VPA.

RESULTS

Forty-six children (age range 1.7-17.4 years) completed the study. The questionnaire data showed no significant difference in bed and wake time, duration of sleep, and time to fall asleep before and after ending VPA treatment, although some qualitative measures on daytime sleepiness improved after tapering VPA. The actigraphy data revealed that the average sleep amount without VPA was reduced in 33 children (9 of them >30 min) and longer in 13 children (1 of them >30 min). The mean Assumed Sleep Time per Day decreased by 15.2 min or 9.5 min when the physiologic decrease of sleep duration within 0.3 years was considered. Also mean Actual Sleep Time per Day was significantly reduced after VPA termination (-15.2 min; after correction -10.7 min). The reduction was only significant in children older than age 6 years.

DISCUSSION

Termination of VPA after long-term treatment leads to a significant reduction of sleep duration in children older than 6 years of age. The change was small in the majority, but considerable in a subgroup of children.

[Restless legs syndrome, periodic limb movements, and psychopharmacology]

Restless legs syndrome (RLS) and the often associated periodic limb movement disorder in sleep (PLMD) frequently occur in the general population as a primary disorder. In addition to organic disease, secondary forms are caused by psychotropic medication. Several antidepressants, antipsychotics, lithium, and opioid withdrawal have been shown to induce or exacerbate RLS and PLMD, while several antiepileptics used as mood stabilizers and some benzodiazepines demonstrate therapeutic potential for treating RLS/PLMD. Systematic or controlled studies for evaluating these side effects still do not exist. Among the antidepressants at higher risk of inducing this disorder are selective serotonin reuptake inhibitors, venlafaxine, and some tetracyclic antidepressants. Under medication with some tricyclic substances, periodic limb movements were observed more often. For some antidepressants with differing transmitter profiles such as bupropion RLS/PLMD ameliorating effects or at least neutral effects (Trazodon, Nortriptylin) have been described in small studies. In case of continued of or newly occurring insomnia a thorough history should be taken to identify a possible RLS/PLMD as an intolerable side effect of treatment. A change in medications should be considered if clinically feasible. In case of RLS/PLMD occurring in psychotic patients switching the antipsychotic and additionally using a second line medication such as antiepileptics or a benzodiazepine should be considered.

Effect of Yi-Gan San on psychiatric symptoms and sleep structure at patients with behavioral and psychological symptoms of dementia

OBJECTIVE

Recently, traditional herbal medicines have been reported to be effective for behavioral and psychological symptoms of dementia (BPSD). This study aims to examine the efficacy of Yi-Gan San (YGS) in the improvement of BPSD and sleep disorders in patients with dementia.

METHODS

Five patients (1 male and 4 female) with dementia in accordance with DSM-IV criteria were investigated. Participants were treated with YGS for 4 weeks. The Nursing Home version of Neuropsychiatric Inventory (NPI-NH) for the assessment of BPSD, the Mini-Mental State Examination (MMSE) for cognitive function, polysomnography for evaluation of sleep structure, and the Pittsburgh Sleep Quality Index for subjective sleep quality were carried out at baseline and at the end of treatment.

RESULTS

All patients completed the trial. Significant improvements in the total NPI-NH score (34.0+/-6.5 to 12.8+/-6.6) as well as delusions, hallucinations, agitation/aggression, anxiety, and irritability/lability, whereas MMSE scores were unchanged. PSG revealed increases in total sleep time, sleep efficiency, stage 2 sleep, and decreases in the number of arousals and periodic limb movements. Subjective sleep quality was also improved. No adverse effects were observed.

CONCLUSION

YGS was effective for BPSD and sleep disturbances, and well tolerated in patients with dementia. Further examinations using a double-blind placebo-controlled design are necessary.

Current guidelines and standards of practice for restless legs syndrome

Algorithms for treatment of restless legs syndrome (RLS) include both nonpharmacologic and pharmacologic therapy. Patients with RLS are divided into 3 groups: (1) those with intermittent RLS symptoms; (2) those with daily RLS symptoms; and (3) those whose symptoms are refractory to standard treatments. Many patients do not require medication, and symptoms often can be relieved with good sleep hygiene and avoidance of medications and factors that provoke symptoms. Recent large-scale clinical trials have proved the efficacy of therapy for RLS when it is required. Several classes of medications are helpful, but dopaminergic therapy appears to be most effective and relieves symptoms rapidly. The first step in managing RLS is to ensure that there is an adequate diagnosis; this involves discriminating RLS from other conditions that may share a number of features. Finally, it is important to tailor treatment to the needs of each individual patient.

Periodic leg movements in sleep and periodic limb movement disorder: prevalence, clinical significance and treatment

Periodic leg movements in sleep (PLMS) are a frequent finding in polysomnography. The prevalence of PLMS is estimated to be 4-11% in adults. In childhood, PLMS rarely occur although medical conditions like sleep apnea syndrome or neuropsychiatric disorders can lead to high rates of PLMS. In the elderly, PLMS are also common in subjects without sleep disturbances. In sleep studies, PLMS are found most frequently in restless legs syndrome (RLS) and often occur in narcolepsy, sleep apnea syndrome and REM sleep behavior disorder. Some patients with otherwise unexplained insomnia or hypersomnia reveal an elevated number of PLMS, a condition defined as periodic limb movement disorder (PLMD). PLMS were found also in various medical and neurological disorders that do not primarily affect sleep. A summary of these is presented. In sleep disorders related to dopaminergic dysfunction such as RLS, PLMS are considered to be a symptom of the disease. In other disorders like primary insomnia, the clinical relevance of PLMS is still being controversially discussed. Studies with findings both pro and contra are referred. To date, only a few studies have evaluated the efficacy of therapeutic substances in reducing PLMS in PLMD patients. Their results need to be confirmed in controlled randomized trials.

EFNS guidelines on management of restless legs syndrome and periodic limb movement disorder in sleep

In 2003, the EFNS Task Force was set up for putting forth guidelines for the management of the Restless Legs Syndrome (RLS) and the Periodic Limb Movement Disorder (PLMD). After determining the objectives for management and the search strategy for primary and secondary RLS and for PLMD, a review of the scientific literature up to 2004 was performed for the drug classes and interventions employed in treatment (drugs acting on the adrenoreceptor, antiepileptic drugs, benzodiazepines/hypnotics, dopaminergic agents, opioids, other treatments). Previous guidelines were consulted. All trials were analysed according to class of evidence, and recommendations formed according to the 2004 EFNS criteria for rating. Dopaminergic agents came out as having the best evidence for efficacy in primary RLS. Reported adverse events were usually mild and reversible; augmentation was a feature with dopaminergic agents. No controlled trials were available for RLS in children and for RLS during pregnancy. The following level A recommendations can be offered: for primary RLS, cabergoline, gabapentin, pergolide, ropinirole, levodopa and rotigotine by transdermal delivery (the latter two for short-term use) are effective in relieving the symptoms. Transdermal oestradiol is ineffective for PLMD.

Antidepressants and periodic leg movements of sleep

BACKGROUND

Frequent electroencephalographic arousals or awakenings associated with periodic leg movements (PLM) might be responsible in part for the complaints of sleep disturbances made by patients treated with antidepressants. Past studies, however, have determined the effects of only certain limited antidepressants, generally in small numbers of subjects, and never in a head-to-head study.

METHODS

A total of 274 consecutive patients taking antidepressants and 69 control subjects not taking antidepressants met criteria among patients referred for overnight diagnostic polysomnography. Periodic leg movements were visually counted and the PLM index (PLMI) was calculated.

RESULTS

The venlafaxine and selective serotonin reuptake inhibitor (SSRI) groups had significantly higher mean PLMIs than control and bupropion groups. Periodic leg movement indexes at thresholds considered to be of potential clinical significance were more statistically prevalent in the SSRI and venlafaxine groups compared with the control and bupropion groups. The odds ratio of having a PLMI greater than 20 was 5.15 for the SSRI group and 5.24 for the venlafaxine group compared with the control group.

CONCLUSIONS

Venlafaxine and SSRI-induced PLM are likely to be the result of enhanced serotonergic availability and secondarily decreased dopaminergic effects. The results of this study might assist in the selection of antidepressants, especially in patients with pronounced sleep complaints.

Periodic limb movement disorder and restless legs syndrome in dialysis patients

BACKGROUND

Sleep disturbances, in particular restless legs or limb movements, during the night are often reported by uremic patients. However, polysomnography (PSG) studies have never been carried out to confirm the actual occurrence of these disorders and the association with other objective and self-reported sleep-wake data.

METHODS

Forty-eight participants were subjected to a 2-day PSG. These data on sleep including periodic limb movements, which are associated with restless legs, were correlated with clinical observations, quality of sleep-wake and life questionnaires, and with biochemical and neurographical measures.

RESULTS

Restless legs syndrome (RLS) was observed in 58.3% of the patients and periodic limb movement disorder (PLMD) occurred in 70.8% of the patients. PLMD was revealed polysomnographically in almost 90% of the RLS patients. Patients with both PLMD and RLS had significantly poorer sleep quality than those with neither disorder or with PLMD alone, both in terms of self-reported data and the PSG. Quality of life was significantly worse in patients with RLS and PLMD compared to those patients with neither disorder. PLMD patients also tended to have a lower quality of life. All other metabolic measures and the results of a nerve conduction test were not correlated with RLS and/or PLMD.

CONCLUSION

There was a high prevalence of severe RLS and PLMD in the present sample of uraemia patients. Nearly all RLS patients had severe PLMD. RLS (in combination with PLMD) in dialysis is associated with poor sleep quality, insomnia complaints, depression and emotional distress. Our results suggest that PLMD per se is also clinically relevant.

Current treatment options for restless legs syndrome

Restless legs syndrome (RLS) is a common but often underdiagnosed neurological disorder characterised by an imperative desire to move the extremities associated with paraesthesias, motor restlessness, worsening of symptoms at rest in the evening or at night and, as a consequence, sleep disturbances particulary. Additionally, most patients with RLS have periodic limb movements during sleep and relaxed wakefulness. The aetiology of RLS remains unknown. Treatment of RLS is generally symptomatic, a causal therapy is possible only in the secondary forms. Dopaminergic agents including levodopa and dopamine agonists such as pergolide, pramipexole, cabergoline and ropinirole are regarded as the treatment of choice for idiopathic RLS, however, the development of augmentation of symptoms, especially under levodopa therapy, may be a major problem. Except in special circumstances, opioids and anticonvulsants such as gabapentin or benzodiazepines, are regarded as second-line treatment. In secondary RLS, the underlying illness should first be treated, although dopaminergic drugs may also be helpful.

Role of dopamine receptor agonists in the treatment of restless legs syndrome

The restless legs syndrome (RLS) is defined by four essential criteria obligatory for clinical diagnosis which were established, and recently revised, by the International RLS Study Group. These are (i) the urge to move the legs, usually accompanied or caused by uncomfortable and unpleasant sensations in the legs, which are (ii) worse during rest/inactivity, (iii) partially or totally relieved by movement and (iv) worse at night/in the evening. Treatment with levodopa leads to symptom relief, but augmentation (occurrence of symptoms before levodopa administration in the evening) may occur, limiting the long-term use of this drug. This article gives an overview of the treatment in general and the role of dopamine receptor agonists in the therapy of RLS and periodic limb movements (PLMs). Dopamine receptor agonists are widely used as an effective treatment for RLS and PLMs, presumably because of their longer half-lives, lower likelihood of augmentation and good tolerability compared with levodopa. It was shown that, for example, pergolide, ropinirole, pramipexole and cabergoline alleviated RLS symptoms in 70-90% of patients. A new non-oral (transdermal) formulation of one dopamine receptor agonist, rotigotine, has recently been developed and shown to be efficacious in RLS. Further research should focus on long-term observations and comparisons of different dopamine receptor agonists in RLS.

Restless legs syndrome

Restless legs syndrome (RLS), first described in 1672 and given its name in 1945, is one of the most common sleep and movement disorders. Modern population-based studies demonstrate a prevalence between 5% and 15% in adult white populations. According to the diagnostic criteria, RLS is defined as an irresistable desire to move limbs, usually associated with paresthesias/dysesthesias and motor restlessness. The symptoms start or worsen at rest and improve with activity. Additionally, the symptoms worsen in the evenings and/or nights, which often results in disturbance of sleep with daytime tiredness. There is often a family history of RLS. Initially, the disease course is usually fluctuating and later may become continuous or chronic-progressive. The diagnosis is based on the patient history and is supported by a normal neurological examination. RLS is confirmed by the finding of periodic limb movements (PLM) in polysomnographic investigations and by a response to dopaminergic medication. A large number of studies have confirmed the effect of levodopa (L-dopa) in the treatment of RLS. A majority of the patients treated over a longer period of time with L-dopa, however, develop problems with an effect called augmentation, where the RLS symptoms begin appearing earlier during the day and involve new parts of the body with increasing severity. A large number of studies have now confirmed that dopamine agonists can also be effective in RLS therapy, and that this treatment seems to involve less risk for augmentation. This paper provides a general review of RLS with a focus on current treatment options.

Clinical symptomatology and treatment of restless legs syndrome and periodic limb movement disorder

Patients with restless legs syndrome (RLS) suffer from sensory and motor symptoms evoked in the limbs at rest. Symptoms increase in the evening and during the night. The circadian rhythm and the presence of involuntary periodic limb movement in sleep (PLMS) which are frequently associated with arousals probably cause the leading symptom of sleep disturbances in RLS. Patients who do not have typical RLS symptoms but whose polysomnography shows PLMS that either impact on sleep continuity or daytime functioning are diagnosed as having the periodic limb movement disorder (PLMD). Dopaminergic agents such as levodopa/dopa decarboxylase inhibitor (DDI) and dopamine agonists are considered the treatment of choice for RLS and PLMS. This article gives an overview of the epidemiology, pathophysiology, clinical symptomatology and diagnosis of RLS and PLMD and focuses on treatment strategies in both disorders.

Treating restless legs syndrome: current pathophysiological concepts and clinical trials

Restless legs syndrome is a distinctive clinical syndrome with a prevalence of about 5% in the general population. One of the outstanding characteristics of restless legs syndrome is its extreme responsiveness to dopaminergic agents. Together with the latest pathophysiological and genetic findings, recent epidemiological and clinical data give a new insight into the classification of restless legs syndrome, thus building the theoretical foundation for the development of new pharmacological methods in its treatment. Current efforts within this area focus on establishing dopaminergic substances for therapy. The hypothesis of a disturbed iron metabolism in restless legs syndrome has been revived by recent theoretical considerations. The present review attempts to explain current strategies of treatment for restless legs syndrome in relation to aetiological, genetic and pathophysiological findings.