The restless legs syndrome

Dopamine dysregulation syndrome in a patient with restless legs syndrome

A middle-aged architect, suffering from familial, idiopathic, levodopa-responsive restless legs syndrome (RLS) progressively abused levodopa for 10 years, to the point of taking 20 tablets/day (4000 mg/day) for 6 months. Such abuse (possibly linked to the rewarding effect of dopamine) has been recently monitored in the context of Parkinson's disease (PD) (the "dopamine dysregulation syndrome"). Physicians who now routinely treat RLS patients with dopaminergic agents should be aware of this abuse potential. This case also constitutes an experimental model. As levodopa abuse has only been described in patients with PD, it was suspected to be promoted by central dopamine depletion (with consequent sensitization of dopamine receptors). This idea should be revised because functional imaging showed that this RLS patient had no dopamine depletion. Later, he had no impulse disorders (no gambling, hypersexuality, excessive shopping), which occur with dopamine agonists, suggesting that levodopa abuse and impulse disorders can result through different mechanisms.

At-risk for pathological gambling: imaging neural reward processing under chronic dopamine agonists

Treatment with dopamine receptor agonists has been associated with impulse control disorders and pathological gambling (PG) secondary to medication in previously unaffected patients with Parkinson's disease or restless legs syndrome (RLS). In a within-subjects design, we investigated the underlying neurobiology in RLS patients using functional magnetic resonance imaging. We scanned 12 female RLS patients without a history of PG. All patients were scanned twice: once whilst taking their regular medication with low dose dopamine receptor agonists and once after a washout phase interval. They performed an established gambling game task involving expectation and receipt or omission of monetary rewards at different levels of probabilities. Upon expectation of rewards, reliable ventral striatal activation was detected only when patients were on, but not when patients were off medication. Upon receipt or omission of rewards, the observed ventral striatal signal under medication differed markedly from its predicted pattern which by contrast was apparent when patients were off medication. Orbitofrontal activation was not affected by medication. Chronic dopamine receptor agonist medication changed the neural signalling of reward expectation predisposing the dopaminergic reward system to mediate an increased appetitive drive. Even without manifest PG, chronic medication with dopamine receptor agonists led to markedly changed neural processing of negative consequences probably mediating dysfunctional learning of contingencies. Intact orbitofrontal functioning, potentially moderating impulse control, may explain why none of the patients actually developed PG. Our results support the notion of a general medication effect in patients under dopamine receptor agonists in terms of a sensitization towards impulse control disorders.

Review of the relationship of restless legs syndrome and periodic limb movements in sleep to hypertension, heart disease, and stroke

Evidence is reviewed documenting an intimate relationship among restless legs syndrome (RLS) / periodic limb movements in sleep (PLMS) and hypertension and cardiovascular and cerebrovascular disease. Sympathetic overactivity is associated with RLS/PLMS, as manifested by increased pulse rate and blood pressure coincident with PLMS. Causality is far from definitive. Mechanisms are explored as to how RLS/PLMS may lead to high blood pressure, heart disease, and stroke: (a) the sympathetic hyperactivity associated with RLS/PLMS may lead to daytime hypertension that in turn leads to heart disease and stroke; (b) in the absence of daytime hypertension, this sympathetic hyperactivity may predispose to heart disease and stroke either directly or indirectly via atherosclerotic plaque formation and rupture; and (c) comorbidities associated with RLS/PLMS, such as renal failure, diabetes, iron deficiency, and insomnia, may predispose to heart disease and stroke. One theoretical cause for sympathetic hyperactivity is insufficient All diencephalospinal dopaminergic neuron inhibition of sympathetic preganglionic neurons residing in the intermediolateral cell columns of the spinal cord. We cannot exclude the possibility that peripheral vascular, cardiovascular, and cerebrovascular disease may also contribute to RLS/PLMS, and mechanisms for these possibilities are also discussed.

Rotigotine transdermal system for the treatment of restless legs syndrome

Rotigotine is a nonergot D3, D2 and D1 dopamine agonist that is currently approved for use in Parkinson’s disease and is awaiting approval for restless legs syndrome (RLS) in Europe. In the USA, it is currently approved for the treatment of early-stage Parkinson’s disease, but not for RLS patients. Oral dopaminergic agents are considered first-line for the treatment of RLS, but may not benefit all patients. Transdermally administered rotigotine delivers medication continuously, which may benefit patients with more severe RLS symptoms that persist or fluctuate throughout the day. It may also benefit patients with gastrointestinal problems or difficulty swallowing. Future research may further define the benefits of minimizing pulsatile stimulation of dopamine receptors. Several studies support the efficacy and tolerability of rotigotine in RLS patients. After treatment with rotigotine, patients had improved International RLS scores compared with placebo. Side effects reported were generally not serious and included application site reaction, nausea, somnolence, dizziness, headache, vomiting and insomnia. The well-known effectiveness and tolerability of dopaminergics, combined with a new pharmaceutical form, represents a promising treatment option for patients with RLS.

Neuromuscular disease in the dialysis patient: an update for the nephrologist

Neuromuscular disease is an extremely common complication of end-stage kidney disease (ESKD), manifesting in almost all dialysis patients, and leading to weakness, reduced exercise capacity, and disability. Recent studies have suggested that hyperkalemia may underlie the development of neuropathy. As such, maintenance of serum K(+) within normal limits between periods of dialysis in ESKD patients manifesting early neuropathic symptoms may reduce neuropathy development and progression. For patients with more severe neuropathic syndromes, increased dialysis frequency or a switch to high-flux dialysis may prevent further deterioration, while ultimately, renal transplantation is required to improve and restore nerve function. Exercise training programs are beneficial for ESKD patients with muscle weakness due to neuropathy or myopathy, and are capable of improving exercise tolerance and quality of life. Specific treatments have recently been evaluated for symptoms of autonomic neuropathy, including sildenafil for impotence and midodrine for intra-dialytic hypotension, and have been shown to be effective and well tolerated. Other important management strategies for neuropathy include attention to foot care to prevent callus and ulceration, vitamin supplementation, and erythropoietin. Treatment with membrane-stabilizing agents, such as amitryptiline and gabapentin, are highly effective in patients with painful neuropathy.

Restless legs syndrome: an early manifestation of Huntington's disease?

BACKGROUND

Far from being uniform, Huntington's disease (HD)'s phenotype encompasses a large variety of motor and non-motor symptoms which occur in various combinations in individual patients.

AIM

To describe an unusual association between restless legs syndrome (RLS) and HD.

METHODS AND RESULTS

We report a patient with an atypical presentation of genetically demonstrated HD, who developed typical RLS a few years prior to and during the course of HD. Common causes of RLS were excluded and the polysomnography confirmed frequent and severe periodic limb movements during sleep and while awake.

CONCLUSIONS

We propose RLS as an uncommon but early feature of HD in some patients, and suggest adding HD to the already long list of RLS secondary to neurodegenerative conditions.

[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.

Elevated estradiol plasma levels in women with restless legs during pregnancy

STUDY OBJECTIVES

Pregnant women have an increased risk of experiencing restless legs syndrome (RLS). Aim of this study was to elucidate the relationship between pregnancy-related hormonal and metabolic changes and RLS symptomatology.

DESIGN

Blood measurements and overnight polysomnography were performed during the third trimester of pregnancy and again 3 months after delivery. We investigated blood hormonal levels (estradiol, prolactin, progesterone, testosterone, follicle-stimulating hormone [FSH], luteinizing hormone [LH], iron, ferritin, hemoglobin) and polysomnographic sleep parameters. Subjective sleep quality and RLS symptoms were evaluated using the Pittsburgh Sleep Quality Index (PSQI) and the International RLS study group (IRLSSG) rating scale.

SETTING

Sleep laboratory.

PARTICIPANTS

Ten pregnant women fulfilling the IRLSSG criteria for RLS diagnosis and 9 pregnant healthy controls underwent the protocol.

INTERVENTIONS

N/A.

RESULTS

Women with RLS showed higher levels of estradiol during pregnancy compared to controls (34,211 +/- 6397 pg/mL vs. 25,475 +/- 7990 pg/mL, P<0.05). Patients also showed more periodic limb movements (PLMs) before and after delivery, particularly during sleep stage 1 and wakefulness (P<0.05). PLMs decreased postpartum in subjects with RLS only (P<0.05); sleep efficiency increased in women without RLS and remained unchanged in patients (P<0.05). No significant differences were found between groups before or after delivery in plasma concentrations of prolactin, progesterone, testosterone, FSH, LH, iron, ferritin or hemoglobin.

CONCLUSIONS

RLS in pregnant women goes along with transiently increased estradiol levels and PLM indices suggesting that estrogens play a pathophysiological role for triggering RLS symptoms during pregnancy.

Review of sleep disorders

Sleep disorders are common and may result in significant morbidity. Examples of the major sleep disturbances in primary care practice include insomnia; sleep-disordered breathing, such as obstructive sleep apnea; central nervous system hypersomnias, including narcolepsy; circadian rhythm sleep disturbances; parasomnias, such as REM sleep behavior disorder; and sleep-related movement disorders, including restless legs syndrome. Diagnosis is based on meticulous inventory of the clinical history and careful physical examination. In some cases referral to a sleep laboratory for further evaluation with polysomnography, a sleep study, is indicated.

Cerebral white matter alterations in idiopathic restless legs syndrome, as measured by diffusion tensor imaging

In search for the pathoanatomical correlate of the restless legs syndrome (RLS), various neuroimaging and electrophysiological techniques have demonstrated partly conflicting results of cortical, subcortical, brainstem, and spinal alterations. In a novel approach, the delineation of potential cerebral white matter tract disruption was investigated by application of quantitative whole brain-based diffusion tensor imaging (DTI) to a well characterized group of 45 patients with idiopathic RLS. The data of patients and 30 healthy controls were statistically compared including computation of regional fractional anisotropy (FA) as a quantitative marker of white matter integrity by use of the tensor imaging and fiber tracking software. In the patient group, multiple subcortical areas of significantly reduced FA were observed bihemispherically in close proximity to the primary and associate motor and somatosensory cortices, in the right-hemispheric thalamus (posterior ventral lateral nucleus), in motor projectional fibers and adjacent to the left anterior cingulum. Together with the results of a recent study by use of an MRI-based gray matter analysis, which localized RLS-associated changes in the sensorimotor cortices, these findings gave support to an altered subcortical network, with the major component of altered cerebral sensorimotor pathways, within a hodological concept of the RLS pathoanatomy.

Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases

BACKGROUND

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular 'reactive oxygen species' (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation.

REVIEW

We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation).The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible.This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, since in some circumstances (especially the presence of poorly liganded iron) molecules that are nominally antioxidants can actually act as pro-oxidants. The reduction of redox stress thus requires suitable levels of both antioxidants and effective iron chelators. Some polyphenolic antioxidants may serve both roles.Understanding the exact speciation and liganding of iron in all its states is thus crucial to separating its various pro- and anti-inflammatory activities. Redox stress, innate immunity and pro- (and some anti-)inflammatory cytokines are linked in particular via signalling pathways involving NF-kappaB and p38, with the oxidative roles of iron here seemingly involved upstream of the IkappaB kinase (IKK) reaction. In a number of cases it is possible to identify mechanisms by which ROSs and poorly liganded iron act synergistically and autocatalytically, leading to 'runaway' reactions that are hard to control unless one tackles multiple sites of action simultaneously. Some molecules such as statins and erythropoietin, not traditionally associated with anti-inflammatory activity, do indeed have 'pleiotropic' anti-inflammatory effects that may be of benefit here.

CONCLUSION

Overall we argue, by synthesising a widely dispersed literature, that the role of poorly liganded iron has been rather underappreciated in the past, and that in combination with peroxide and superoxide its activity underpins the behaviour of a great many physiological processes that degrade over time. Understanding these requires an integrative, systems-level approach that may lead to novel therapeutic targets.

Ropinirole treatment for restless legs syndrome

Restless legs syndrome (RLS) is a chronic neurological disorder associated with sleep disturbance. Ropinirole, a non-ergot dopamine agonist, has been widely studied for the treatment of moderate-to-severe primary RLS in a comprehensive clinical development program. In these studies, ropinirole was effective in significantly improving the symptoms of RLS, compared with placebo, in patients with moderate-to-severe primary RLS. These improvements are supported by data from individual studies, as well as by pooled analyses. Significant improvements in RLS symptoms were observed within 2 nights of treatment. Ropinirole also produced significant benefits on objective measures of RLS motor symptoms, such as periodic leg movements; and on subjective measures of sleep, ropinirole was generally well tolerated. A newly developed extended-release formulation of ropinirole may benefit patients who warrant an extended duration of therapy.

Acupuncture for restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) is a common movement disorder for which patients may seek treatment with acupuncture. However, the benefits of acupuncture in the treatment of RLS are unclear and have not been evaluated in a systematic review until now.

OBJECTIVES

To evaluate the efficacy and safety of acupuncture therapy in patients with RLS.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2007), MEDLINE (January 1950 to February 2007), EMBASE (January 1980 to 2007 Week 8), Chinese Biomedical Database (CBM) (1978 to February 2007), China National Knowledge Infrastructure (CNKI) (1979 to February 2007), VIP Database (1989 to February 2007), Japana Centra Revuo Medicina (1983 to 2007) and Korean Medical Database (1986 to 2007). Four Chinese journals, relevant academic conference proceedings and reference lists of articles were handsearched.

SELECTION CRITERIA

Randomized controlled trials and quasi-randomized trials comparing acupuncture with no intervention, placebo acupuncture, sham acupuncture, pharmacological treatments, or other non-acupuncture interventions for primary RLS were included. Trials comparing acupuncture plus non-acupuncture treatment with the same non-acupuncture treatment were also included. Trials that only compared different forms of acupuncture or different acupoints were excluded.

DATA COLLECTION AND ANALYSIS

Two authors independently identified potential articles, assessed methodological quality and extracted data. Relative risk (RR) was used for binary outcomes and weighted mean difference for continuous variables. Results were combined only in the absence of clinical heterogeneity.

MAIN RESULTS

Fourteen potentially relevant trials were identified initially, but twelve of them did not meet the selection criteria and were excluded. Only two trials with 170 patients met the inclusion criteria. No data could be combined due to clinical heterogeneity between trials. Both trials had methodological and/or reporting shortcomings. No significant difference was detected in remission of overall symptoms between acupuncture and medications in one trial (RR 0.97, 95% CI 0.76 to 1.24). Another trial found that dermal needle therapy used in combination with medications and massage was more effective than medications and massage alone, in terms of remission of unpleasant sensations in the legs (RR 1.36, 95% CI 1.06 to 1.75; WMD -0.61, 95% CI -0.96 to -0.26) and reduction of RLS frequency (WMD -3.44, 95% CI -5.15 to -1.73). However, there was no significant difference for the reduction in either the longest or the shortest duration of RLS (WMD -2.58, 95% CI -5.92 to 0.76; WMD -0.38, 95% CI -1.08 to 0.32).

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine whether acupuncture is an efficacious and safe treatment for RLS. Further well-designed, large-scale clinical trials are needed.

Restless legs syndrome in women: a review

Restless legs syndrome (RLS) is a neurological disorder with significant negative impact on sleep and quality of life, yet data suggest that it is frequently underdiagnosed. The clinical features, diagnosis, epidemiology, pathophysiology, and treatment options for RLS are reviewed and discussed, with particular emphasis on RLS in women. RLS is characterized by unpleasant sensations causing an urge to move the legs. RLS symptoms are exacerbated by rest, relieved by movement, and worse at night than during the day. The motor and sensory symptoms of RLS can have a negative impact on patients' sleep, resulting in a reduction in daytime functioning and overall quality of life. The prevalence of RLS is reported to increase with age and to be up to almost twice as high in women as in men. The explanation for this is unknown, although there is evidence that parity may be a factor. Diagnosis of RLS is made using four essential criteria based on the patient's report of sensorimotor symptoms. Several large, double-blind, placebo-controlled studies have demonstrated that dopamine agonists, such as ropinirole and pramipexole, are an efficacious first-line therapy for the treatment of RLS symptoms. As RLS is more prevalent in women, professionals working in the field of women's health need to be aware of this condition, its differential diagnosis, and the treatment options available. Accurate diagnosis is essential to facilitate appropriate management and treatment. Dopamine agonists have been shown to be an effective therapy for patients with moderate to severe symptoms of RLS.

One year open-label safety and efficacy trial with rotigotine transdermal patch in moderate to severe idiopathic restless legs syndrome

BACKGROUND

Long-term efficacy and tolerability data are not yet available for patch formulations of dopamine agonists in restless legs syndrome.

METHODS

Efficacy and safety of rotigotine (0.5-4mg/24h), formulated as a once-daily transdermal system (patch), were investigated in an open extension (SP710) of a preceding 6-week placebo-controlled trial (SP709, 341 randomized patients) in patients with idiopathic restless legs syndrome. For efficacy assessment the international RLS severity scale (IRLS), the RLS-6 scales, the clinical global impressions (CGI) and the QoL-RLS questionnaire were administered. In addition, long-term tolerability and safety were assessed.

RESULTS

Of 310 patients who finished the controlled trial, 295 (mean age 58+/-10 years, 66% females) with a mean IRLS score of 27.8+/-5.9 at baseline of SP709 were included. We report results after one year of this ongoing long-term trial. Two hundred twenty patients (retention rate=74.6%) completed the 12-month follow-up period. The mean daily dose was 2.8+/-1.2mg/24h with 4mg/24h (40.6%) being the most frequently applied dose; 14.8% were sufficiently treated with 0.5 or 1.0mg/24h. The IRLS total score improved by ?17.4+/-9.9 points between baseline and end of Year 1 (p<0.001). The other measures of severity, sleep satisfaction and quality of life supported the efficacy of rotigotine (p<0.001 for pre-post-comparisons of all efficacy variables). The tolerability was described as "good" or "very good" by 80.3% of all patients. The most common adverse events were application site reactions (40.0%), which led to withdrawal in 13.2%. Further relatively frequent adverse events were nausea (9.5%) and fatigue (6.4%). Two drug-related serious adverse events, nausea and syncope, required hospitalization. Symptoms of augmentation were not reported by the patients.

CONCLUSION

Rotigotine provided a stable, clinically relevant improvement in all efficacy measures throughout one year of maintenance therapy. The transdermal patch was safe and generally well tolerated by the majority of patients. Comparable to any transdermal therapy, application site reactions were the main treatment complication.

Genetics of restless legs syndrome

Restless legs syndrome (RLS) is a highly familial trait with heritability estimates of about 50%. It is a polygenetic disorder in which a number of variants contribute to the phenotype. Linkage studies in families with RLS revealed several loci but have not yet led to the identification of disease-causing sequence variants. Phenocopies, nonpenetrance, and possible intrafamilial heterogeneity make it difficult to define the exact candidate region. Genome-wide association studies identified variants within intronic or intergenic regions of MEIS1, BTBD9, and MAP2K5/LBOXCOR1. Carriers of one risk allele had a 50% increased risk of developing RLS. MEIS1 and LBXCOR1 are developmental factors and raise new pathophysiologic questions for RLS. These variants have weak and moderate effects and increase the risk of developing RLS. It is still possible that strong effects explain the occurrence of RLS in families. Therefore, linkage and association studies should be used congruently to dissect the complete genetic architecture of RLS.

[Restless-legs syndrome]

Restless-legs syndrome (RLS) is a sensorimotor disorder, characterized by an irresistible urge to move the legs usually accompanied or caused by uncomfortable and unpleasant sensations. It begins or worsens during periods of rest or inactivity, is partially or totally relieved by movements and is exacerbated or occurs at night and in the evening. RLS sufferers represent 2 to 3% of the general population in Western countries. Supportive criteria include a family history, the presence of periodic-leg movements (PLM) when awake or asleep and a positive response to dopaminergic treatment. The RLS phenotypes include an early onset form, usually idiopathic with a familial history and a late onset form, usually secondary to peripheral neuropathy. Recently, an atypical RLS phenotype without PLM and l-DOPA resistant has been characterized. RLS can occur in childhood and should be distinguished from attention deficit/hyperactivity disorder, growing pains and sleep complaints in childhood. RLS should be included in the diagnosis of all patients consulting for sleep complaints or discomfort in the lower limbs. It should be differentiated from akathisia, that is, an urge to move the whole body without uncomfortable sensations. Polysomnographic studies and the suggested immobilization test can detect PLM. Furthermore, an l-DOPA challenge has recently been validated to support the diagnosis of RLS. RLS may cause severe-sleep disturbances, poor quality of life, depressive and anxious symptoms and may be a risk factor for cardiovascular disease. In most cases, RLS is idiopathic. It may also be secondary to iron deficiency, end-stage renal disease, pregnancy, peripheral neuropathy and drugs, such as antipsychotics and antidepressants. The small-fiber neuropathy can mimic RLS or even trigger it. RLS is associated with many neurological and sleep disorders including Parkinson's disease, but does not predispose to these diseases. The pathophysiology of RLS includes an altered brain-iron metabolism, a dopaminergic dysfunction, a probable role of pain control systems and a genetic susceptibility with nine loci and three polymorphisms in genes serving developmental functions. RLS treatment begins with the elimination of triggering factors and iron supplementation when deficient. Mild or intermittent RLS is usually treated with low doses of l-DOPA or codeine; the first-line treatment for moderate to severe RLS is dopaminergic agonists (pramipexole, ropinirole, rotigotine). In severe, refractory or neuropathy-associated RLS, antiepileptic (gabapentin, pregabalin) or opioid (oxycodone, tramadol) drugs can be used.

Intradialytic aerobic exercise training ameliorates symptoms of restless legs syndrome and improves functional capacity in patients on hemodialysis: a pilot study

We present the first study on the influence of exercise training on restless legs syndrome (RLS) in patients on hemodialysis (HD). Restless legs syndrome has been treated pharmacologically with satisfactory results; however, side effects and rebound phenomena have been reported. Intradialytic exercise training effectively counteracts uremia-induced catabolism; nevertheless, it remains unknown whether patients with RLS undergoing HD benefit from such programs. The aims of the current study were to evaluate the effect of 16-weeks aerobic exercise training in the severity of RLS and in the functional capacity and the quality of life of patients with RLS on HD. Fourteen patients on HD (four female, mean age 59 +/- 16 years) with untreated RLS were assigned, according to their will, to either the exercise group (Ex-group, n = 7), and participated in a 16-week supervised intradialytic aerobic exercise training, or to the control group (Con-group, n = 7), and continued usual activities. Primary aim was to compare the International RLS (IRLS) study group rating scale, functional ability, and quality of life in baseline and the end of the 16 weeks. Exercise training reduced IRLS score by 42% (p = 0.02). Furthermore, it significantly improved indices of functional ability (p = 0.02), exercise capacity (p = 0.01), quality of life (p = 0.03), and sleep quality (p = 0.01). In the Con-group no changes were observed. In conclusion, aerobic exercise training is safe and efficacious in reducing RLS symptoms and improving quality of life in patients with RLS on HD.

Epidemiology of restless legs syndrome in Korean adults

STUDY OBJECTIVES

To investigate the prevalence of restless legs syndrome (RLS) in Korea.

DESIGN

A large population-based telephone interview method using the Korean version of the Johns Hopkins telephone diagnostic interview for the RLS.

SETTING

A computer aided telephone interview method.

PARTICIPANTS

A total of 5,000 subjects (2,470 men and 2,530 women) were interviewed in depth. A representative sample aged 20 to 69 years was constituted according to a stratified, multistage random sampling method.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Of the respondents, 373 respondents (7.5%) of the population (pop) met the criteria for the definite or probable RLS groups: 194 (3.9% of pop) respondents fulfilled the criteria for definite RLS and 179 (3.6% of pop) respondents fulfilled the criteria for probable RLS. The prevalence of RLS was generally higher for women than men (4.4% vs. 3.3% for definite, 8.7% vs. 6.2% for definite plus probable). About 90% of RLS individuals were experiencing symptoms at the time of the interview and this was similar for both RLS groups. Seventy-four respondents (1.48%) reported symptoms were moderately or severely distressing and were therefore classified as RLS "sufferers." Of those with a diagnosis of RLS sufferer, 24.3% reported being treated for their symptoms, compared to 12.4% of RLS not designated a "sufferer."

CONCLUSION

RLS is common and underdiagnosed in Korea with nearly 1% of the population reporting disturbed sleep related to their RLS. These results are comparable to other countries.

Ropinirole treatment for restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) is a chronic neurological disorder associated with sleep disturbance.

OBJECTIVE

Prepare a drug evaluation of the non-ergot dopamine agonist ropinirole in RLS.

METHODS

Review of scientific literature on RLS, particularly focusing on treatment with ropinirole.

CONCLUSION

Ropinirole has been studied for treatment of moderate to severe primary RLS in a comprehensive clinical development program. Ropinirole significantly improved symptoms of RLS, versus placebo, in patients with primary RLS. These improvements are supported by data from individual studies and pooled analyses. Significant improvements in RLS symptoms were observed within two nights of treatment. Ropinirole also produced significant benefits on objective measures of RLS motor symptoms, such as periodic leg movements, and subjective measures of sleep. Ropinirole was generally well tolerated.

Clinical trials in restless legs syndrome--recommendations of the European RLS Study Group (EURLSSG)

The European Restless Legs Syndrome (RLS) Study Group (EURLSSG) is an association of European RLS experts who are actively involved in RLS research. A major aim of the Study Group is the development and continuous improvement of standards for diagnosis and treatment of RLS. Several members developed study designs and evaluation methods in investigator-initiated trials early in the 1990s, and all members have since contributed to many pivotal and nonpivotal drug trials for the treatment of RLS. The recommendations on clinical investigations of pharmacological treatment of RLS patients summarize the group's expertise and knowledge acquired through clinical trials. The recommendations primarily address how to plan and conduct confirmatory, randomized clinical studies in patients with idiopathic RLS. Advice is presented for the diagnosis of RLS and clinical and polysomnographic inclusion and exclusion criteria. Primary and secondary endpoints for an evaluation of efficacy are based on a critical description of validated methods for both short- and long-term trials, also in special populations (children, pregnant women, elderly patients). The recommendations include the assessment of augmentation. Finally, general issues including the evaluation of safety and tolerability, as well as specific neurological and cardiovascular risks and sleep attacks/daytime somnolence, are discussed. The aim of these recommendations is to support research groups or pharmaceutical companies in the design of optimized study protocols.

Update of the pathophysiology of the restless-legs-syndrome

The Restless Legs Syndrome (RLS) is a heterogeneous disease. Symptomatic or secondary forms encompass iron deficiency, uremia, pregnancy, polyneuropathy, and other causes. The so-called idiopathic RLS syndrome preferentially affects patients with a younger onset before the age of 30. Here we summarize pathophysiological results along the anatomical route, beginning at the cortex and followed by the basal ganglia, thalamus, A11 neurones, substantia nigra, brainstem nuclei, and spinal cord. Genetic risk variants for RLS have recently been identified in two genes, one of them the homeobox gene MEIS1, known to be involved in embryonic development and variants in a second locus containing the genes encoding mitogen-activated protein kinase MAP2K5, and the transcription factor LBXCOR1. A third one, the BTBD9 gene with unknown function encodes a BTB(POZ) domain. Accordingly, new concepts on pathophysiology have to bridge conventional knowledge with possible consequences deriving from these findings. Furthermore, this may create a framework to help understand why dopamine, opioid, and some anticonvulsant therapies are effective in RLS patients.

Definition of restless legs syndrome, how to diagnose it, and how to differentiate it from RLS mimics

Restless legs syndrome (RLS) is a clinical diagnosis based primarily on self-reports of individuals. The International RLS Study Group has published diagnostic criteria that are essential for an operational diagnosis of RLS; further clinical features are considered by the group supportive for or associated with RLS. However, sensitivity and specificity are not perfect and "mimics" of RLS have been reported, i.e., other conditions like nocturnal cramps sometimes can appear to fulfill the essential diagnostic criteria indicating the need for more thorough understanding of the diagnostic criteria and better differential diagnoses. To contribute to the accuracy of diagnostic processes in RLS, we recapitulate the definition of RLS as an urge to move focused on the legs (and arms in some patients). This urge to move often but not always occurs together with dysesthesia, i.e. unpleasant abnormal sensations appearing without any apparent sensory stimulation. The urge to move and any accompanying dysesthesia must be engendered by rest, relieved by movement and worse in the evening or night. Succinctly, RLS can be summarized in medical terminology as a "movement-responsive quiescegenic nocturnal focal akathisia usually with dysesthesias." Empirical approaches to investigate the independence of the essential criteria "worsening at night" and "worsening at rest" are reported. Possible differential diagnoses of RLS are discussed under the perspective of the NIH diagnostic criteria of RLS. Standardized methods to assess a RLS diagnosis are presented which might improve differential diagnosis and in general the reliability and validity of RLS diagnosis.

Genetics of restless legs syndrome (RLS): State-of-the-art and future directions

Several studies demonstrated that 60% of restless legs syndrome (RLS) patients have a positive family history and it has been suggested that RLS is a highly hereditary trait. To date, several loci have been mapped but no gene has been identified yet. Phenocopies and possible nonpenetrants made it difficult to detect a common segregating haplotype within the families. Defining the exact candidate region is hampered by possible intrafamilial, allelic, and nonallelic heterogeneity. One important prerequisite for future successful genetic studies in RLS is the availability of large and thoroughly phenotyped patients and family samples for linkage as well as association studies.

Cortical grey matter alterations in idiopathic restless legs syndrome: An optimized voxel-based morphometry study

An impairment of central somatosensory processing is assumed in restless legs syndrome (RLS). Although functional neuroimaging in RLS gave evidence to the presence of widespread functional changes in various brain areas, structural changes at the cortical level were not reported to be RLS-associated to date. Here, an analysis of high-resolution three-dimensional magnetic resonance imaging (MRI) was performed in 63 patients with idiopathic RLS by use of optimized voxel-based morphometry, in order to investigate if cortical areas might be altered in volume at group level according to the phenomenology of RLS. The comparison of the RLS patients versus controls yielded significant regional decreases of gray matter volume at corrected P < 0.05 in the bihemispheric primary somatosensory cortex, which additionally extended into left-sided primary motor areas. All clusters correlated both with the severity of RLS symptoms and with disease duration. These results, for the first time, give in vivo evidence to structural neocortical gray matter alterations in RLS patients. The alterations in the sensorimotor cortices might add to the pathophysiological concepts of idiopathic RLS.

Low RLS prevalence and awareness in central Greece: an epidemiological survey

Restless legs syndrome (RLS) is a sensorimotor disorder with a general population prevalence of 3-10%. A single, previous epidemiological study performed in south-east Europe reported the lowest prevalence rate amongst European countries. We conducted a population-based survey of RLS in central Greece. A total of 4200 subjects were randomly recruited. We used the international RLS study group criteria for diagnosis and the severity scale for severity assessment in subjects with RLS. We also included questions to assess the level of awareness of RLS in our region. A total of 3033 subjects were screened. The overall lifetime prevalence was 3.9% with a female-to-male ratio of 2.6:1. Nearly half of RLS patients reported moderate to severe intensity of symptoms. After adjustment for multiple comparisons we found no association of RLS with education level, smoking, alcohol intake, caffeine consumption, shift work, professional pesticide use or comorbid illness. Our study revealed a low level of awareness amongst the population and physicians in our region and sub-optimal management. We provide further evidence for low prevalence of RLS in south-east Europe and a low level of awareness of RLS in our region.

Iron deficiency anemia in infancy is associated with altered temporal organization of sleep states in childhood

The highest prevalence of iron deficiency anemia (IDA) in infancy coincides with a time of rapid changes in sleep organization. Since IDA in infancy is associated with long-lasting neurofunctional effects despite iron treatment, the normal development of sleep patterns might be affected. Night polysomnographic recordings were performed in 55 healthy 4-y-old children (former IDA = 27, nonanemic controls = 28). Both groups were followed from infancy and were similar in background characteristics. The duration of each waking episode was measured, as was the duration of each episode of nonrapid eye movement (NREM) sleep stages 1 (NREM1), 2 (NREM2), and 3-4 (SWS), and rapid eye movement (REM) sleep. The data were analyzed according to the successive thirds of the total sleep time (TST). Relative to controls, former IDA children showed: a) longer duration of REM sleep episodes in the first third and shorter in the last third; b) more REM sleep episodes in the first third and fewer in the second third; and c) shorter latency to the first REM sleep episode and shorter NREM stage 2 and SWS episodes within the first sleep cycle. The results show that early IDA is associated with long-lasting alterations in the temporal organization of sleep patterns.

Pathological gambling associated with dopamine agonist use in restless legs syndrome

Dopamine agonists (DA) have been associated with pathological gambling (PG) and other compulsive behaviors in Parkinson's disease (PD). Although these medications are used in other conditions, we are not aware of other reports of PG exclusive to treatment for idiopathic PD. We present a case of PG arising in the context of DA use for restless legs syndrome.

Comorbidity in restless legs syndrome among a sample of Swedish adults

BACKGROUND

Restless legs syndrome (RLS) is a neurological movement disorder, which often causes sleep problems. However, the comorbidity of this disorder is not well known. This study aimed to document the prevalence of RLS in the general population of Sweden and to identify factors associated with this condition.

METHODS

A cross-sectional study was performed in Sweden. One thousand subjects aged 18-90 years old underwent telephone interviews. The questionnaire assessed such factors as sleep variables, depressive mood, treatment of diabetes mellitus, and treatment with drugs for depression during the previous four-week period. RLS was diagnosed based on the minimal criteria provided by the International RLS Study Group.

RESULTS

The prevalence of RLS was 5% (5.7% in women, 3.5% in men). Severe or very severe RLS symptoms during the previous week were noted by 64% of the RLS subjects. Factors associated with RLS were insomnia, excessive daytime sleepiness, periodic limb movements in sleep, and depressed mood. Those affected by RLS were not more often consumers of drugs for depression than non-RLS subjects.

CONCLUSIONS

RLS is prevalent in the general population in Sweden. RLS negatively influenced sleep and was associated with depressed mood. Antidepressive drug treatment was not associated with RLS.

Levodopa for idiopathic restless legs syndrome: Evidence-based review

Restless legs syndrome (RLS) is a sensory motor disorder characterized by a distressing urge to move the legs and sometimes also other parts of the body usually accompanied by a marked sense of discomfort or pain in the leg or other affected body part. The prevalence of RLS is estimated at 2.7 to 5% of adults and it is more common in women. The treatment of RLS with levodopa has been reported thus a systematic synthesis of evidence is necessary to evaluate the effectiveness and safety of levodopa for RLS. Systematic review of randomized or quasi-randomized, double blind trials on levodopa. Relief of restless legs symptoms marked on a validated scale, subjective sleep quality, sleep quality measured by night polysomnography and actigraphy, quality of life measured by subjective measures, adverse events associated with the treatments. Nine eligible clinical trials were included. The subjective analyses of these studies showed contradictory results, although the objective analyses showed that treatment group had a statistically significant improvement of periodic leg movement (PLM) index, favoring the treatment group. The most commonly adverse event seen was gastrointestinal symptoms. The short-term treatment with levodopa was demonstrated effective and safety for PLM, but there was only few trials assessing long-term treatment and the augmentation phenomenon in RLS. Further long-term randomized controlled trials using standard follow-up measurements as the International RLS Study Group Rating Scale are necessary.

Iron-deficiency anemia is associated with altered characteristics of sleep spindles in NREM sleep in infancy

OBJECTIVE

To determine the effects of iron-deficiency anemia on the development of non-rapid-eye-movement (NREM) sleep stages, as indexed by sleep spindles.

STUDY DESIGN

Patterns of sleep spindles during NREM sleep stages 2 and 3-4 (slow-wave-sleep, SWS) were compared in 26 otherwise healthy 6-month-old Chilean infants with iron-deficiency anemia and 18 non-anemic control infants. From polygraphic recordings, EEG activity was analyzed for sleep spindles to assess their number (density), duration, frequency, and inter-spindle interval.

RESULTS

Iron-deficient anemic infants differed from the control group by having sleep spindles with reduced density, lower frequency, and longer inter-spindle intervals in NREM sleep stage 2 and SWS.

CONCLUSIONS

These results provide evidence of delayed sleep spindle patterns in iron-deficient anemic infants, suggesting that iron is an essential micronutrient for the normal progression of NREM sleep pattern development in the human.