Augmentation in restless legs syndrome is associated with low ferritin

Clinical efficacy and safety of intravenous ferric carboxymaltose for treatment of restless legs syndrome: a multicenter, randomized, placebo-controlled clinical trial

STUDY OBJECTIVES

Iron therapy is associated with improvements in restless legs syndrome (RLS). This multicenter, randomized, double-blind study evaluated the effect of intravenous ferric carboxymaltose (FCM) on RLS.

METHODS

A total of 209 adult patients with a baseline International RLS (IRLS) score ≥ 15 were randomized (1:1) to FCM (750 mg/15 mL) or placebo on study days 0 and 5. Ongoing RLS medication was tapered starting on Day 5, with the goal of discontinuing treatment or achieving the lowest effective dose. Co-primary efficacy endpoints were changed from baseline in IRLS total score and the proportion of patients rated as much/very much improved on the Clinical Global Impression (CGI)-investigator (CGI-I) scale at day 42 in the "As-Treated" population.

RESULTS

The "As-Treated" population comprised 107 FCM and 101 placebo recipients; 88 (82.2%) and 68 (67.3%), respectively, completed the day 42 assessment. The IRLS score reduction was significantly greater with FCM versus placebo: least-squares mean (95% confidence interval [CI]) -8.0 (-9.5, -6.4) versus -4.8 (-6.4, -3.1); p = .0036. No significant difference was observed in the proportion of FCM (35.5%) and placebo (28.7%) recipients with a CGI-I response (odds ratio 1.37 [95% CI: 0.76, 2.47]; p = .2987). Fewer patients treated with FCM (32.7%) than placebo (59.4%) received RLS interventions between day 5 and study end (p = .0002). FCM was well tolerated.

CONCLUSIONS

The IRLS score improved with intravenous FCM versus placebo, although the combination of both co-primary endpoints was not met. Potential methodological problems in the study design are discussed.

Association of low serum ferritin levels with augmentation in patients with restless legs syndrome: A systematic review and meta-analysis

BACKGROUND

Augmentation of restless legs syndrome (RLS) is an iatrogenic side effect induced by dopaminergic agents, and it is a major cause of therapeutic failure. Iron deficiency is a risk factor for RLS, but its effects on the development of RLS augmentation are unclear. This meta-analysis aimed to elucidate the association between serum ferritin and RLS augmentation.

METHODS

We searched the PubMed, Cochrane Library, Embase, ClinicalKey, ScienceDirect, and ProQuest databases for studies comparing the serum ferritin levels of patients with augmented RLS and nonaugmented RLS. A meta-analysis based on a random-effects model was conducted. Levodopa equivalent dose (LED), International Restless Legs Study Group Severity Rating Scale (IRLS), and serum hemoglobin levels were also analyzed.

RESULTS

Six observational studies fulfilled the eligibility criteria of this meta-analysis. A total of 220 RLS patients with augmentation and 687 RLS patients without augmentation were included. The results revealed that augmented RLS was significantly associated with low serum ferritin levels (p = 0.002), high LEDs (p = 0.026), and nonsignificantly associated with high IRLS scores (p = 0.227).

CONCLUSIONS

A low serum ferritin level is associated with RLS augmentation. For patients with RLS who are iron deficient, iron supplements can not only relieve their fundamental RLS symptoms but also lower the risk of RLS augmentation. Moreover, non-dopminergic agents should be considered as the first-line treatment for patients with persistent low serum ferritin levels or those with moderate to severe RLS to prevent augmentation.

Exploring the causes of augmentation in restless legs syndrome

Long-term drug treatment for Restless Legs Syndrome (RLS) patients can frequently result in augmentation, which is the deterioration of symptoms with an increased drug dose. The cause of augmentation, especially derived from dopamine therapy, remains elusive. Here, we review recent research and clinical progress on the possible mechanism underlying RLS augmentation. Dysfunction of the dopamine system highly possibly plays a role in the development of RLS augmentation, as dopamine agonists improve desensitization of dopamine receptors, disturb receptor interactions within or outside the dopamine receptor family, and interfere with the natural regulation of dopamine synthesis and release in the neural system. Iron deficiency is also indicated to contribute to RLS augmentation, as low iron levels can affect the function of the dopamine system. Furthermore, genetic risk factors, such as variations in the BTBD9 and MEIS1 genes, have been linked to an increased risk of RLS initiation and augmentation. Additionally, circadian rhythm, which controls the sleep-wake cycle, may also contribute to the worsening of RLS symptoms and the development of augmentation. Recently, Vitamin D deficiency has been suggested to be involved in RLS augmentation. Based on these findings, we propose that the progressive reduction of selective receptors, influenced by various pathological factors, reverses the overcompensation of the dopamine intensity promoted by short-term, low-dose dopaminergic therapy in the development of augmentation. More research is needed to uncover a deeper understanding of the mechanisms underlying the RLS symptom and to develop effective RLS augmentation treatments.

Effects of iron-deficient diet on sleep onset and spinal reflexes in a rodent model of Restless Legs Syndrome

Restless Legs Syndrome (RLS) is a common sensorimotor and a sleep disorder that affects 2.5-10% of the European and North American populations. RLS is also often associated with periodic leg movements during sleep (PLMS). Despite ample evidence of genetic contributions, the underlying mechanisms that elicit the sensory and motor symptoms remain unidentified. Clinically, RLS has been correlated with an altered central iron metabolism, particularly in the brain. While several animal models have been developed to determine the outcome of an altered iron homeostasis on brain function, the potential role of an altered iron homeostasis on sleep and sensorimotor circuits has not yet been investigated. Here, we utilize a mouse model to assess the effects of an iron-deficient (ID) but non-anemic state on sleep time and episodes, and sensorimotor reflexes in male and female mice. We found that animals on the ID diet displayed an increased expression of the transferrin receptor in the spinal cord, confirming the results of previous studies that focused only on the impact of ID in the brain. We also demonstrate that the ID diet reduced hematocrit levels compared to controls but not into the anemic range, and that animals on the ID diet exhibited RLS-like symptoms with regard to sleep onset and spinal cord reflex excitability. Interestingly, the effects on the spinal cord were stronger in females than in males, and the ID diet-induced behaviors were rescued by the return of the animals to the control diet. Taken together, these results demonstrate that diet-induced ID changes to CNS function are both inducible and reversible, and that they mimic the sleep and sensorimotor RLS symptoms experienced in the clinic. We therefore propose replacing the commonly used phrase "brain iron deficiency" (BID) hypothesis in the RLS research field with the term "iron deficiency in the central nervous system" (ID-CNS), to include possible effects of altered iron levels on spinal cord function.

How effective are treatment guidelines for augmented RLS?

Study Objectives

The objective of this study was to assess the effectiveness of current treatment guidelines for restless legs syndrome (RLS) augmentation in patients on dopamine agonists (DAs) which recommend a cross-titration strategy to an alpha-2-delta ligand (A2D) and/or opioid.

Methods

Consecutive new consultations for RLS with both augmentation and active treatment with DAs at the time of initial assessment were included if followed >5 months. Clinical information from the semi-structured initial consultation, and subsequent visits until their most recent/final visit was extracted. Clinical Global Impression-Severity (CGI-S) and Clinical Global Impression-Improvement (CGI-I) scores were retrospectively determined by two independent evaluators.

Results

In the 63 patients with augmented RLS on DAs, followed for 5–59 months (mean = 28, SD = 14), the average age was 67.6 (SD = 9.8) and 63% were female. Mean duration of prior dopaminergic therapy was 11.6 years (SD = 6.7) and average pramipexole equivalent dose was 1.23 mg (SD = 1.22 mg). At baseline, RLS was “moderate-markedly” severe (CGI-S = 4.9). At the final/most recent visit, 78% (49/63) were classified as Responders (CGI-I ≤ 2, “Much” or “Very Much Improved”) with an average CGI-S of 2.4 (“borderline-mildly ill”). Responders (59%) were more likely to have discontinued DAs than Non-Responders (40%), and mean opioid doses were higher in Responders (39 vs 20 MME). No differences in baseline DA dose, final A2D dose, or iron therapy were observed between groups. Responders did have significantly more severe RLS, more sleep maintenance insomnia, and greater subjective daytime sleepiness at baseline (p < 0.05).

Conclusions

Guideline-based management is effective in most patients with augmented RLS on DAs.

Restless Legs Syndrome: Challenges to Treatment

For a long time, dopaminergic treatment (DT) was the medication for restless legs syndrome. Although DT is effective and safe over the short-term, complications develop over longer periods, including augmentation, tolerance, and impulse control disorders. Nowadays, it is recommended that first-line treatment should be alpha-2 ligands, which are more effective in the absence of previous DT. As a second-line treatment, opioids, such as oxycodone extended-release with naloxone, are approved in Europe. Brain iron should be monitored before and during treatment and corrected if necessary. Two new promising non-DTs are being developed: perampanel and dipyridamole. More research is needed.

[Restless legs syndrome]

Restless legs syndrome (RLS) is seen widely in clinical practice. RLS commonly occurs at night time and presents with unpleasant or uncomfortable sensations in the legs that causes an urge to move them. This article describes the epidemiology, risk factors and pathophysiology of RLS. There is a detailed description of clinical presentations, diagnostic criteria and also management of RLS.

Changes in Hepcidin Serum Levels Correlate with Clinical Improvement in Idiopathic Restless Legs Syndrome Patients

BACKGROUND

Restless legs syndrome (RLS) is a common sensory motor neurological disorder that is related to iron-dopamine dysregulation and immune system alteration. We aimed to assess the effects of serum hepcidin, an iron-regulating hormone, in drug-naive RLS patients compared to healthy controls and to evaluate its role in helping to predict clinical improvement after treatment with dopamine agonist.

METHODS

Nonanemic and drug-naive RLS patients (n = 18) and healthy controls (n = 15) were enrolled. The serum hepcidin and iron-related values in the serum were measured upon the first visit in both groups and 12 weeks later after dopaminergic treatment in 12 patients. Information about sociodemographic characteristics, sleep-related profiles, mood and anxiety was obtained upon the first visit in all participants as well as after treatment in RLS patients.

RESULTS

Serum hepcidin levels exhibited no significant differences between patients with drug-naïve RLS and healthy controls at diagnosis (7.1 ± 2.4 vs. 7.0 ± 3.2 ng/mL, p = 0.357). Decreased hepcidin levels were significantly associated with decreased RLS severity (β = 0.002, 95% CI = 0.00-0.00, p = 0.005) and improved quality of life (β = 0.002, 95% CI = 0.00-7.01, p = 0.044) in a dose-dependent manner after 12 weeks of treatment with a dopamine agonist. This association was independent of age, sex, inflammatory markers, sleep quality, insomnia, daytime sleepiness, depression and anxiety.

CONCLUSIONS

This study demonstrates the role of hepcidin in evaluating the positive therapeutic response in RLS.

Restless Legs Syndrome and Other Common Sleep-Related Movement Disorders

PURPOSE OF REVIEW

In this article, the different sleep-related movement disorders are discussed with special attention given to restless legs syndrome (RLS).

RECENT FINDINGS

The differential diagnosis of sleep-related movement disorders can often be challenging; therefore, it is essential to have accurate information to make a correct diagnosis. This article focuses on RLS, highlighting the change in the paradigm of initial treatment, the role played by iron (pathophysiologic and therapeutic), and how to approach possible complications occurring with long-term treatment.

SUMMARY

RLS is one of the most common neurologic conditions, and it is common in clinical practice to find patients experiencing symptoms suggestive of RLS. Neurologists must be careful and thorough in the diagnosis, excluding RLS mimics. The decisions regarding which specific sleep-related movement disorder is present and how it should be treated are important because in certain cases, especially in RLS, adverse effects and long-term complications are frequently reported with the use of certain drugs.

Pharmacological treatments of augmentation in restless legs syndrome patients

Augmentation, a treatment-induced paradoxical worsening of the symptoms of restless legs syndrome (RLS) that is caused by long-term dopaminergic therapy, in particular with higher doses, remains the major challenge of RLS treatment. The mainstay of treatment continues to be preventing augmentation, either by starting RLS therapy with alternative drugs or by sensitizing physicians about the absolute necessity of respecting approved dosages of dopaminergic drugs when treating RLS and never exceeding the maximum recommended dosages. In the case of a positive diagnosis of augmentation, treatment consists of reducing or eliminating dopaminergic therapy, ensuring that serum ferritin is clearly higher than the level assumed to be necessary from a hematological point of view and/or switching treatment to alternative drugs such as α2δ ligands, opiates, or to combination therapy.

Iron for the treatment of restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) is a common neurologic disorder that is associated with peripheral iron deficiency in a subgroup of patients. It is unclear whether iron therapy is effective treatment for RLS.

OBJECTIVES

To evaluate the efficacy and safety of oral or parenteral iron for the treatment of restless legs syndrome (RLS) when compared with placebo or other therapies.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycNFO, and CINAHL for the time period January 1995 to September 2017. We searched reference lists for additional published studies. We searched Clinicaltrials.gov and other clinical trial registries (September 2017) for ongoing or unpublished studies.

SELECTION CRITERIA

Controlled trials comparing any formulation of iron with placebo, other medications, or no treatment, in adults diagnosed with RLS according to expert clinical interview or explicit diagnostic criteria.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial quality, with discussion to reach consensus in the case of any disagreement. The primary outcome considered in this review was restlessness or unpleasant sensations, as experienced subjectively by the patient. We combined treatment/control differences in the outcomes across studies using random-effects meta-analyses. We analysed continuous data using mean differences (MDs) where possible and performed standardised mean difference (SMD) analyses when different measurements were used across studies. We calculated risk ratios (RRs) for dichotomous data using the Mantel-Haenszel method and 95% confidence intervals (CIs). We analysed study heterogeneity using the I² statistic. We used standard methodological procedures expected by Cochrane. We performed GRADE analysis using GRADEpro.

MAIN RESULTS

We identified and included 10 studies (428 total participants, followed for 2-16 weeks) in this review. Our primary outcome was restlessness or uncomfortable leg sensations, which was quantified using the International Restless Legs Scale (IRLS) (range, 0 to 40) in eight trials and a different RLS symptom scale in a ninth trial. Nine studies compared iron to placebo and one study compared iron to a dopamine agonist (pramipexole). The possibility for bias among the trials was variable. Three studies had a single element with high risk of bias, which was lack of blinding in two and incomplete outcome data in one. All studies had at least one feature resulting in unclear risk of bias.Combining data from the seven trials using the IRLS to compare iron and placebo, use of iron resulted in greater improvement in IRLS scores (MD -3.78, 95% CI -6.25 to -1.31; I²= 66%, 7 studies, 345 participants) measured 2 to 12 weeks after treatment. Including an eighth study, which measured restlessness using a different scale, use of iron remained beneficial compared to placebo (SMD -0.74, 95% CI -1.26 to -0.23; I² = 80%, 8 studies, 370 participants). The GRADE assessment of certainty for this outcome was moderate.The single study comparing iron to a dopamine agonist (pramipexole) found a similar reduction in RLS severity in the two groups (MD -0.40, 95% CI -5.93 to 5.13, 30 participants).Assessment of secondary outcomes was limited by small numbers of trials assessing each outcome. Iron did not improve quality of life as a dichotomous measure (RR 2.01, 95% CI 0.54 to 7.45; I²=54%, 2 studies, 39 participants), but did improve quality of life measured on continuous scales (SMD 0.51, 95% CI 0.15 to 0.87; I²= 0%, 3 studies, 128 participants), compared to placebo. Subjective sleep quality was no different between iron and placebo groups (SMD 0.19, 95% CI -0.18 to 0.56; I² = 9%, 3 studies, 128 participants), nor was objective sleep quality, as measured by change in sleep efficiency in a single study (-35.5 +/- 92.0 versus -41.4 +/- 98.2, 18 participants). Periodic limb movements of sleep were not significantly reduced with iron compared to placebo ( SMD -0.19, 95% CI -0.70 to 0.32; I² = 0%, 2 studies, 60 participants). Iron did not improve sleepiness compared to placebo, as measured on the Epworth Sleepiness Scale (data not provided, 1 study, 60 participants) but did improve the daytime tiredness item of the RLS-6 compared to placebo (least squares mean difference -1.5, 95% CI -2.5 to -0.6; 1 study, 110 participants). The GRADE rating for secondary outcomes ranged from low to very low.Prespecified subgroup analyses showed more improvement with iron in those trials studying participants on dialysis. The use of low serum ferritin levels as an inclusion criteria and the use or oral versus intravenous iron did not show significant subgroup differences.Iron did not result in significantly more adverse events than placebo (RR 1.48, 95% CI 0.97 to 2.25; I²=45%, 6 studies, 298 participants). A single study reported that people treated with iron therapy experienced fewer adverse events than the active comparator pramipexole.

AUTHORS' CONCLUSIONS

Iron therapy probably improves restlessness and RLS severity in comparison to placebo. Iron therapy may not increase the risk of side effects in comparison to placebo. We are uncertain whether iron therapy improves quality of life in comparison to placebo. Iron therapy may make little or no difference to pramipexole in restlessness and RLS severity, as well as in the risk of adverse events. The effect on secondary outcomes such as quality of life, daytime functioning, and sleep quality, the optimal timing and formulation of administration, and patient characteristics predicting response require additional study.

French consensus: Augmentation syndrome in restless legs syndrome

Augmentation syndrome is one of the most severe complications of RLS. It is characterised by a worsening of treated symptoms; principally an increase in the severity of symptoms and an earlier onset time. Augmentation syndrome occurs primarily with dopaminergic treatments. It is crucial for the patient to be sufficiently well informed to prevent its occurrence and the prescription of too high doses of dopaminergic agonists avoided. In the presence of augmentation syndrome confirmed using the diagnostic criteria, the specialist treating the restless legs syndrome should quickly modify the patient's treatment. In this article, our expert group proposes a practical strategy for the diagnosis, prevention and treatment of augmentation syndrome.

Identification and treatment of augmentation in patients with restless legs syndrome: practical recommendations

Restless legs syndrome (RLS) is a chronic disorder causing clinically significant discomfort to approximately 3% of adults. Although RLS was first identified centuries ago, our understanding of this disorder, its causes, and its treatments is still evolving. In particular, our knowledge of the potential negative effects of RLS treatments, including dopaminergic augmentation, continues to expand. Augmentation, which refers to a paradoxical treatment-related increase in RLS symptoms, has been associated with all three dopamine agonists approved for the treatment of RLS - rotigotine, pramipexole, and ropinirole. This review presents key information on prevention and treatment of dopaminergic augmentation from the recently published consensus-based guidelines issued by the International RLS Study Group task force in conjunction with the European RLS Study Group and the RLS Foundation for first-line treatment of RLS/Willis-Ekbom disease. If dopamine agonists are used to treat RLS, it is recommended that the dosage should be kept as low as possible without exceeding the maximum dose recommended for RLS treatment. As the frequency of augmentation with the rotigotine patch may only be slightly lower than that associated with pramipexole or ropinirole, medications that are effective and have little risk of augmentation, such as alpha-2-delta ligands, may be considered for initial RLS treatment. In addition, we present our clinical experience with treating patients with dopaminergic augmentation by highlighting 2 case studies and practical considerations when treating different patient populations. Applying current RLS augmentation diagnosis and treatment guidelines, as well as collecting detailed histories of worsening RLS symptoms, is critical for patient safety and effective management of RLS augmentation.

Association between the neutrophil-to-lymphocyte ratio, a new marker of systemic inflammation, and restless legs syndrome

INTRODUCTION

Restless legs syndrome (RLS), also known as Willis-Ekbom disease, is characterised by abnormal sensations in the legs as well as dysaesthesia. Although the aetiology of RLS has not yet been determined, it may be associated with systemic inflammation. The neutrophil-to-lymphocyte ratio (NLR) is a new and simple marker indicating systemic inflammation. The present study aimed to investigate the relationship between systemic inflammation and RLS through the use of the NLR.

METHODS

A total of 75 newly diagnosed patients with RLS and 56 healthy control subjects were included in the study. Baseline NLR was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. The NLRs of the two groups were compared.

RESULTS

There were no significant differences in gender and age between the two groups. The NLR was 1.96 ± 0.66 in the patient group and 1.67 ± 0.68 in the control group (p = 0.005). Receiver operating characteristic analysis was performed to determine the cut-off value of NLR to predict RLS. The NLR was predictive at 1.58 with a 64% sensitivity and 50% specificity (95% confidence interval 0.55-0.74, area under curve 0.648 ± 0.05). The NLR was found to be statistically higher in patients with RLS and may be used to predict RLS.

CONCLUSION

The aetiology of RLS remains undetermined. The present study showed that systemic inflammation may play a role in RLS. However, RLS could also be associated with systemic inflammatory diseases. This relationship is supported by high NLR values, which are related to chronic systemic inflammation.

Restless legs syndrome augmentation among Japanese patients receiving pramipexole therapy: Rate and risk factors in a retrospective study

To investigate the rate of and risk factors for restless legs syndrome (RLS) augmentation in Japanese patients receiving pramipexole (PPX) treatment. Records of 231 consecutive patients with idiopathic RLS who received PPX therapy for more than one month in a single sleep disorder center were analyzed retrospectively. Augmentation was diagnosed based on the Max Planck Institute criteria; associated factors were identified by logistic regression analysis. Mean age at PPX initiation was 60.6 ± 14.9 years and mean treatment duration was 48.5 ± 26.4 months. Augmentation was diagnosed in 21 patients (9.1%). Daily PPX dose and treatment duration were significantly associated with augmentation. By analyzing the receiver operating characteristic curve, a PPX dose of 0.375 mg/day was found to be the optimal cut-off value for predicting augmentation. After stratifying patients according to PPX treatment duration, at median treatment duration of 46 months, optimal cut-off values for daily doses were 0.375 and 0.500 mg/day for <46 months and ≥46 months of treatment, respectively. The RLS augmentation with PPX treatment in Japanese patients was occurred at rate of 9.1%, being quite compatible with previously reported rates in Caucasian patients. The symptom could appear within a relatively short period after starting the treatment in possibly vulnerable cases even with a smaller drug dose. Our results support the importance of keeping doses of PPX low throughout the RLS treatment course to prevent augmentation.

[Geriatric inpatients with iron deficiency-associated Restless Legs Syndrome. A retrospective analysis]

OBJECTIVE

The Restless Legs Syndrome (RLS) is a clinically relevant condition in geriatric patients. An association between iron deficiency and RLS is largely acknowledged. The clinical and therapeutic management of iron deficiency-associated RLS has been, however, poorly evaluated in geriatric patients.

METHODS

Data from all RLS inpatients admitted to a geriatric unit between 2009 and 2011 were retrospectively collected on demographics and clinical characteristics, iron status, drug treatment including iron substitution, as well as comprehensive geriatric assessment (CGA) scores.

RESULTS

RLS was diagnosed in 56 of the 4,063 admitted patients during the two years. Of the RLS cases, 20 (36%) showed iron deficiency. Thirteen of these were treated with iron substitution according to the existing guidelines. Both RLS patients with and without iron deficiency showed a significant clinical improvement between admission to discharge according to the CGA scores.

CONCLUSION

Iron substituted geriatric patients with iron deficiency-associated RLS substantially benefited from the treatment, similarly to RLS patients without iron deficiency. A multidimensional assessment, careful iron metabolism examination and adequate treatment choice should be equally importantly considered in geriatric patients with RLS.

[Iron deficiency, Fatigue and Restless-Legs-Syndrome]

Iron deficiency without anaemia is a widespread health problem that often remains undetected. In this context, neurological and psychopathological problems like fatigue and poor concentration are a major issue, but also in Restless-Legs-Syndrome (RLS) iron deficiency is a key element.The exact pathogenesis is often unknown, however, it is known that iron is involved in several very important metabolic processes in the human body. In particular when it comes to fatigue and RLS, it's assumed that reduced activity of tyrosine hydroxylase - a central iron-dependent element of dopamine synthesis - can lead to deficiencies.As part of the therapy, oral iron supplementation is considered to be treatment of choice since it's most cost-effective and well tolerated. Intravenous iron treatment is indicated if primary attempts were not sufficient or not tolerated. To successfully replenish iron storages, about 500-1000 mg are needed. Doses of 200 mg can be administered (iron sucrose) or 1-2 single doses as for ferric carboxymaltose. A check of ferritin-levels not earlier than 8 weeks after last administration is recommended.

Restless legs syndrome

Restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED), is a common movement disorder characterised by an uncontrollable urge to move because of uncomfortable, sometimes painful sensations in the legs with a diurnal variation and a release with movement. The pathophysiology is only partially known and a genetic component together with dopaminergic and brain iron dysregulation plays an important role. Secondary causes for RLS need to be excluded. Treatment depends on the severity and frequency of RLS symptoms, comprises non-pharmacological (eg lifestyle changes) and pharmacological interventions (eg dopaminergic medication, alpha-2-delta calcium channel ligands, opioids) and relieves symptoms only. Augmentation is the main complication of long-term dopaminergic treatment of RLS. This article will provide a clinically useful overview of RLS with provision of diagnostic criteria, differential diagnoses, possible investigations and different treatment strategies with their associated complications.

Guidelines for the first-line treatment of restless legs syndrome/Willis-Ekbom disease, prevention and treatment of dopaminergic augmentation: a combined task force of the IRLSSG, EURLSSG, and the RLS-foundation

A Task Force was established by the International Restless Legs Syndrome Study Group (IRLSSG) in conjunction with the European Restless Legs Syndrome Study Group (EURLSSG) and the RLS Foundation (RLS-F) to develop evidence-based and consensus-based recommendations for the prevention and treatment of long-term pharmacologic treatment of dopaminergic-induced augmentation in restless legs syndrome/Willis-Ekbom disease (RLS/WED). The Task Force made the following prevention and treatment recommendations: As a means to prevent augmentation, medications such as α2δ ligands may be considered for initial RLS/WED treatment; these drugs are effective and have little risk of augmentation. Alternatively, if dopaminergic drugs are elected as initial treatment, then the daily dose should be as low as possible and not exceed that recommended for RLS/WED treatment. However, the physician should be aware that even low dose dopaminergics can cause augmentation. Patients with low iron stores should be given appropriate iron supplementation. Daily treatment by either medication should start only when symptoms have a significant impact on quality of life in terms of frequency and severity; intermittent treatment might be considered in intermediate cases. Treatment of existing augmentation should be initiated, where possible, with the elimination/correction of extrinsic exacerbating factors (iron levels, antidepressants, antihistamines, etc.). In cases of mild augmentation, dopamine agonist therapy can be continued by dividing or advancing the dose, or increasing the dose if there are breakthrough night-time symptoms. Alternatively, the patient can be switched to an α2δ ligand or rotigotine. For severe augmentation the patient can be switched either to an α2δ ligand or rotigotine, noting that rotigotine may also produce augmentation at higher doses with long-term use. In more severe cases of augmentation an opioid may be considered, bypassing α2δ ligands and rotigotine.

Relationship between prevalence and severity of restless legs syndrome and anemia in patients with systemic lupus erythematosus

AIM

Our aim was to evaluate the relationship between the prevalence and severity of restless legs syndrome (RLS) and the anemia in patients with systemic lupus erythematosus (SLE).

METHODS

This was a case-control study which was conducted at the rheumatology clinic of a university affiliated hospital, including 62 patients with SLE and 62 age- and sex-matched healthy controls. The patients were divided into two groups in terms of their hemoglobin levels. The criterion for anemia was hemoglobin level lower than 12 g/dL in females and 13 g/dL in males.

RESULTS

Nineteen patients (30.6%) in the patient group were diagnosed with RLS, and International RLS Study Group Rating Scale (IRLSSG-RS) score was 10.7 ± 9.5 (median:10.0 [range:0.0-30.0]). Three subjects (4.8%) in the control group had RLS, and the IRLSSG-RS score was 0.7 ± 3.3 (median:0.0 [range:0.0-18.0]). The prevalence of RLS and the IRLSSG-RS score were higher in the patient group than those in the control group (P < 0.001). Ten SLE patients (50%) with anemia had RLS, and their IRLSSG-RS score was 14.5 ± 9.9 (median:21.0 [range:11.0-30.0]). Nine SLE patients (21.4%) without anemia had RLS and their IRLSSG-RS was 9.0 ± 8.9 (median:21.0 [range:11.0-24.0]). Significant differences were present in the prevalence of RLS and the IRLSSG-RS score between SLE patients with and without anemia (P = 0.024, P = 0.044, respectively).

CONCLUSION

The present study demonstrated that the prevalence of RLS was higher in patients with SLE than that of the normal population. Results of this study also suggested that anemia was associated with higher frequency of and more severe RLS in patients with lupus.

Therapeutic advances in restless legs syndrome (RLS)

Levodopa and dopamine agonists have been the main treatment for restless legs syndrome during the past decades. Although their efficacy has been well documented over the short term, long-term dopaminergic treatment is often complicated by augmentation, loss of efficacy, and other side effects. Recent large randomized controlled trials provide new evidence for the efficacy of high-potency opioids and α2δ ligands, and several post hoc analyses, meta-analyses, algorithms, and guidelines have been published, often with a specific focus, for example, on augmentation, or on management of restless legs syndrome during pregnancy. Several new contributions to understanding the pathophysiology of restless legs syndrome have been published, but at this time, whether they will have an impact on treatment possibilities in the future cannot be estimated.

Augmentation of restless leg syndrome (Willis-Ekbom disease) during long-term dopaminergic treatment

Restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED), is a common sensorimotor disorder that can generally be effectively managed in the primary care clinic. However, some treatment complications may arise. According to the recommendations of the International Restless Legs Syndrome Study Group, non-ergot dopamine-receptor agonists have over the past years been one of the first-line treatments for patients with RLS/WED requiring pharmacological therapy. Augmentation is the main complication of long-term dopaminergic treatment of RLS/WED and is defined as an overall worsening of symptoms beyond pretreatment levels in patients who experienced an initial positive therapeutic response. Once identified on the basis of its characteristic clinical features, augmentation requires careful management. In order to provide clinicians with a comprehensive understanding of this common treatment complication, this review discusses the clinical features of augmentation, and its differentiation from morning rebound, symptom fluctuations and natural disease progression. Reported incidences of augmentation in clinical trials of dopaminergic RLS/WED therapies are summarized. Finally, the hypothetical pathophysiology of augmentation and the current recommendations for management of patients with augmented RLS/WED symptoms are discussed.

Sleep in Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder

Sleep problems are common in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). Sleep problems in these disorders may not only worsen daytime behaviors and core symptoms of ASD and ADHD but also contribute to parental stress levels. Therefore, the presence of sleep problems in ASD and ADHD requires prompt attention and management. This article is presented in 2 sections, one each for ASD and ADHD. First, a detailed literature review about the burden and prevalence of different types of sleep disorders is presented, followed by the pathophysiology and etiology of the sleep problems and evaluation and management of sleep disorders in ASD and ADHD.

Long-Term Treatment of Restless Legs Syndrome (RLS): An Approach to Management of Worsening Symptoms, Loss of Efficacy, and Augmentation

Restless legs syndrome (RLS) is a common, frequently chronic, sensorimotor neurological disorder characterized by nocturnal leg dysesthesias and an irresistible urge to move the legs, usually resulting in sleep disturbance. Dopaminergic agonists, alpha-2-delta calcium-channel ligands, and opioids have all demonstrated efficacy to relieve symptoms of RLS and improve sleep. However, long-term treatment with dopamine agonists (the most commonly prescribed agents) is often characterized by worsening symptoms and loss of efficacy. A more worrisome complication of dopaminergic agents is augmentation, an iatrogenic worsening of RLS symptoms that can produce progressively more severe symptoms resulting in around-the-clock restlessness and near sleeplessness. Recent research has yielded consensus regarding a precise definition of augmentation and has contributed to improved knowledge regarding strategies for preventing this complication. When RLS symptoms worsen during the course of treatment, the clinician must consider the myriad of environmental, medical, pharmacologic, and psychiatric factors that can exacerbate RLS. In the absence of fully developed, evidence-based guidelines there remains uncertainty regarding the optimal management strategy if augmentation develops. However, we discuss several key principles based on the available published data and the authors' clinical experience. We also explore the recent increasing interest in alternative initial treatment strategies that avoid dopamine agonists and their associated complications altogether.

Restless legs syndrome: clinical presentation diagnosis and treatment

Restless legs syndrome (RLS) is a circadian disorder of sensory-motor integration that may be related to genetically determined dysregulation of iron transport across the blood-brain barrier. Dopamine agonists (DAs) have been considered the first-line therapy, but with the growing appreciation of problems associated with long-term treatment, particularly augmentation and impulse control disorder, alpha-2-delta drugs, such as gabapentin, are now considered the first line of treatment in patients with troublesome RLS. Opioids can be considered as an alternative therapy, particularly in patients with DA-related augmentation. In more severe cases, a combination therapy may be required. Intravenous iron therapy may be considered on those patients with refractory RLS.

A review of current treatment strategies for restless legs syndrome (Willis-Ekbom disease)

Restless legs syndrome (RLS), recently renamed Willis-Ekbom disease (WED), is a common movement disorder. It is characterised by the need to move mainly the legs due to uncomfortable, sometimes painful sensations in the legs, which have a diurnal variation and a release with movement. Management is complex. First, centres should establish the severity of RLS using a simple 10-item RLS severity rating scale (IRLS). They should also exclude secondary causes, in particular ensuring normal iron levels. Mild cases can be managed by lifestyle changes, but patients with a IRLS score above 15 usually require pharmacological treatment. Dopaminergic therapies remain the mainstay of medical therapies, with recent evidence suggesting opioids may be particularly effective. This article focuses on the different treatment strategies in RLS, their associated complications and ways to manage them.

Diagnosis, comorbidities, and management of restless legs syndrome

OBJECTIVE

This narrative review describes the differential diagnosis of restless legs syndrome, and provides an overview of the evidence for the associations between RLS and potential comorbidities. Secondary causes of RLS and the characteristics of pediatric RLS are also discussed. Finally, management strategies for RLS are summarized.

METHODS

The review began with a comprehensive PubMed search for 'restless legs syndrome/Willis-Ekbom disease' in combination with the following: anxiety, arthritis, attention-deficit hyperactivity disorder, cardiac, cardiovascular disease, comorbidities, depression, end-stage renal disease, erectile dysfunction, fibromyalgia, insomnia, kidney disease, liver disease, migraine, mood disorder, multiple sclerosis, narcolepsy, neuropathy, obesity, pain, Parkinson's disease, polyneuropathy, pregnancy, psychiatric disorder, sleep disorder, somatoform pain disorder, and uremia. Additional papers were identified by reviewing the reference lists of retrieved publications.

RESULTS AND CONCLUSIONS

Although clinical diagnosis of RLS can be straightforward, diagnostic challenges may arise when patients present with comorbid conditions. Comorbidities of RLS include insomnia, depressive and anxiety disorders, and pain disorders. Differential diagnosis is particularly important, as some of the medications used to treat insomnia and depression may exacerbate RLS symptoms. Appropriate diagnosis and management of RLS symptoms may benefit patient well-being and, in some cases, may lessen comorbid disease burden. Therefore, it is important that physicians are aware of the presence of RLS when treating patients with conditions that commonly co-occur with the disorder.

Augmentation in restless legs syndrome patients in Korea

PURPOSE

Augmentation has been known as the major complication of long-term dopaminergic treatment of restless legs syndrome (RLS). However, there have been no reports on the prevalence of augmentation in Korea. Thus, we aimed to assess the rate of augmentation and evaluate related factors in Korean RLS patients.

METHODS

Ninety-four idiopathic RLS patients who have been treated over a period of at least 6 months were enrolled. Thirty subjects were treated with a dopamine agonist only, and 64 were treated with a dopamine agonist and alpha two delta ligands. We assessed the clinical characteristics of those RLS subjects and evaluated the rate of augmentation. Augmentation was assessed using the NIH criteria for augmentation by two RLS experts independently.

RESULTS

Eleven subjects (11.7%) were classified as having definitive or highly suggestive clinical indication of augmentation. In comparing the augmentation group with the non-augmentation group, there were no significant differences of baseline clinical characteristics. Four (13.3%) of the dopamine agonists monotherapy group and seven (10.9%) of the combination therapy group were categorized as augmentation. There was no significant difference in the augmentation rate between these two groups.

CONCLUSIONS

We found an 11.7% augmentation rate in Korean RLS subjects. There was no difference in the rate of RLS augmentation between the dopaminergic monotherapy group and the combined treatment group. It may be related with using a similar dosage of dopaminergic drugs.

The higher prevalence of non-right handers among patients with restless leg syndrome

Restless leg syndrome (RLS) is a common disorder described as an urge to move the legs. Dopamine, the main neuro-transmitter in the pathophysiology of RLS, is likely related to the development of brain laterality and human handedness. We aimed to compare the prevalence of RLS in right and non-right handers. A checklist including Edinburgh questioner for handedness, questions for RLS diagnosis and basic characteristics was filled out by a sample of population. The exclusion criteria included prolonged use of dopaminergic or psychologic drugs and having diseases with similar symptoms to RLS. The frequency of non-right handers in RLS patients was compared with the controls by Chi square test. P value less than 0.05 was considered significant. 164 persons were divided into RLS patients (69) and non-RLS controls (95). There was no significant difference between demographic characteristics. The prevalence of non-right handers in RLS patients was significantly more than non-RLS controls (P: 0.03). Our finding regarding the higher prevalence of non-right handers in RLS patients needs more justifications based on neuroscientists' guides. RLS as a disease in which dopaminergic system involves is highly assumed to be linked with handedness. This is just a hypothesis that impaired modulation of immune system in left handers may be accompanied with lower dopamine levels in RLS.

Iron in Restless Legs Syndrome

A link between restless legs syndrome (RLS) and iron has been recognized for several decades. Yet, the precise role that iron or other components of iron metabolism play in bringing about RLS is still a matter of debate. During the last few years, many new pieces of evidence from genetics, pathology, imaging, and clinical studies have surfaced. However, the way this evidence fits into the larger picture of RLS as a disease is not always easily understood. To provide a better understanding of the complex interplay between iron metabolism and RLS and highlight areas that need further elucidation, we systematically and critically review the current literature on the role of iron in RLS pathophysiology and treatment with a special emphasis on genetics, neuropathology, cell and animal models, imaging studies, and therapy.

Treatment of restless legs syndrome

OPINION STATEMENT

Restless legs syndrome (RLS) is a common, sensorimotor, circadian sleep disorder characterized by the urge to move the legs, particularly at nighttime. It is important to differentiate primary and secondary RLS from other conditions, which can mimic the symptoms of RLS, in particular neuropathy and cramps. Despite considerable advances, the understanding of RLS pathophysiology remains incomplete. Many hypotheses focus on central nervous system structures, although there is increasing evidence that peripheral structures may also be important. There is insufficient evidence at the moment to recommend changes in lifestyle, nutritional supplements and any specific nonpharmacologic treatments. The first-line drugs continue to be dopaminergic medications, including pramipexole, ropinirole, rotigotine transdermal patch and levodopa. However, the phenomenon of RLS augmentation, a paradoxical worsening of symptoms by dopaminergic treatment remains as major problem in treatment of RLS, and prevention of augmentation is one of the main goals in the management of RLS. RLS requires treatment only if it has a significant impact on the patient's nighttime sleep or daily activities. Doses of dopamine agonists should be kept to the minimum required for acceptable symptom reduction. Augmentation may require treatment withdrawal, with prescription of alternate medication. Alternative or additional pharmacologic treatment with a lower level of overall quality of evidence includes opioids (codeine, tramadol, and oxycodone) and anticonvulsants (gabapentin, gabapentin enacarbil, and pregabalin). The choice of the medication should be based on the severity of RLS and the effectiveness of medication for the short-term or long-term treatment of RLS. Iron deficiency must be identified at diagnosis; treatment may improve RLS symptoms and potentially may lower risk of augmentation. There is no clear evidence for treatment of secondary RLS, but agents used in primary RLS should be tried. Comparative long-term trials are required to assess differences in efficacy and augmentation rates between medications used for treatment of RLS.

Dilution of candidates: the case of iron-related genes in restless legs syndrome

Restless legs syndrome (RLS) is a common multifactorial disease. Some genetic risk factors have been identified. RLS susceptibility also has been related to iron. We therefore asked whether known iron-related genes are candidates for association with RLS and, vice versa, whether known RLS-associated loci influence iron parameters in serum. RLS/control samples (n = 954/1814 in the discovery step, 735/736 in replication 1, and 736/735 in replication 2) were tested for association with SNPs located within 4 Mb intervals surrounding each gene from a list of 111 iron-related genes using a discovery threshold of P = 5 × 10(-4). Two population cohorts (KORA F3 and F4 with together n = 3447) were tested for association of six known RLS loci with iron, ferritin, transferrin, transferrin-saturation, and soluble transferrin receptor. Results were negative. None of the candidate SNPs at the iron-related gene loci was confirmed significantly. An intronic SNP, rs2576036, of KATNAL2 at 18q21.1 was significant in the first (P = 0.00085) but not in the second replication step (joint nominal P-value = 0.044). Especially, rs1800652 (C282Y) in the HFE gene did not associate with RLS. Moreover, SNPs at the known RLS loci did not significantly affect serum iron parameters in the KORA cohorts. In conclusion, the correlation between RLS and iron parameters in serum may be weaker than assumed. Moreover, in a general power analysis, we show that genetic effects are diluted if they are transmitted via an intermediate trait to an end-phenotype. Sample size formulas are provided for small effect sizes.

Efficacy, safety and risk of augmentation of rotigotine for treating restless legs syndrome

The present study aimed to examine the long-term efficacy and safety of rotigotine treatment for restless legs syndrome (RLS), as well as the rate of clinically significant augmentation, in a 1-year open-label study of Japanese subjects. Japanese patients with RLS who had been treated with rotigotine or placebo in a double-blind trial were enrolled in a 1-year, open-label, uncontrolled extension study and treated with rotigotine at a dose of up to 3 mg/24 h after an 8-week titration phase. Outcomes included International Restless Legs Syndrome Study Group rating scale (IRLS scale), Pittsburgh Sleep Quality Index (PSQI), safety, and investigator-/expert panel-assessed augmentation (including Augmentation Severity Rating Scale). Overall, 185 patients entered the open-label study and 133 completed the study. IRLS and PSQI total scores improved throughout the 52-week treatment period (IRLS, from 23.2±5.1 to 7.8±7.6 and PSQI, from 8.0±3.1 to 5.0±2.9). Treatment-emergent adverse events were mild to moderate in severity, and included application site reactions (52.4%) and nausea (28.6%). Clinically significant augmentation occurred in five patients (2.7%). These results indicate a good long-term efficacy of rotigotine for treating RLS, with a relatively low risk of clinically significant augmentation.

Strategies for the treatment of restless legs syndrome

Restless legs syndrome (RLS) is a common neurological disorder of unknown etiology that is managed by therapy directed at relieving its symptoms. Treatment of patients with milder symptoms that occur intermittently may be treated with nonpharmacological therapy but when not successful, drug therapy should be chosen based on the timing of the symptoms and the needs of the patient. Patients with moderate to severe RLS typically require daily medication to control their symptoms. Although the dopamine agonists, ropinirole and pramipexole have been the drugs of choice for patients with moderate to severe RLS, drug emergent problems like augmentation may limit their use for long term therapy. Keeping the dopamine agonist dose as low as possible, using longer acting dopamine agonists such as the rotigotine patch and maintaining a high serum ferritin level may help prevent the development of augmentation. The α2δ anticonvulsants may now also be considered as drugs of choice for moderate to severe RLS patients. Opioids should be considered for RLS patients, especially for those who have failed other therapies since they are very effective for severe cases. When monitored appropriately, they can be very safe and durable for long term therapy. They should also be strongly considered for treating patients with augmentation as they are very effective for relieving the worsening symptoms that occur when decreasing or eliminating dopamine agonists.