Incidence of Augmentation in Primary Restless Legs Syndrome Patients May Not Be That High: Evidence From A Systematic Review and Meta-Analysis

Sex-based disparities in dopamine agonist response in patients with restless legs syndrome

This study aimed to investigate sex-related differences in the response to ropinirole and pramipexole in patients with restless legs syndrome (RLS). By analysing clinical parameters and polysomnographic (PSG) findings, we sought to elucidate the potential factors related to sex disparities modulating treatment responses and sleep quality in RLS. A total of 41 drug-free patients with RLS, aged ≥18 years, underwent two consecutive nocturnal PSG recordings, without medication at baseline; before the second night, 26 patients received an oral dose of 0.25 mg pramipexole whereas 15 received 0.5 mg ropinirole. After each PSG recording, patients self-evaluated the severity of their previous night symptoms by means of an ad hoc visual analogue scale (VAS). At baseline, sleep efficiency and percentage of Stage N2 tended to be higher in females while wakefulness after sleep onset was significantly higher in males. After treatment, total leg movements during sleep (LMS), periodic LMS (PLMS), and periodicity indexes were significantly lower in females than in males. The VAS score was lower after treatment in all patients, without differences between the two sexes. This study demonstrates a higher acute responsiveness of PLMS to dopamine agonists (pramipexole and ropinirole) in females than in males with RLS. These findings might be explained by differential sex-related expression of dopamine receptors, especially D3, within the central nervous system. In addition, our findings provide translational hints toward a better tailored and sex-specific approach to the treatment of RLS associated with PLMS, with dopamine agonist possibly associated with a better outcome in females than in males.

Suspected Agomelatine-induced restless legs syndrome: a case report

BACKGROUND

Restless Legs Syndrome (RLS) is a sensorimotor disorder characterized by unpleasant and distressing sensations in the lower limbs that are more pronounced in the evening, commence or worsen at rest, and show partial or complete relief following movement. It can occur as a primary disorder, secondary to medical conditions or treatment with medications including but not limited to antidepressants or antipsychotics.

CASE PRESENTATION

A 32-year old man with major depressive disorder showed partial response to Escitalopram 10 mg daily. Agomelatine 25 mg at night was added to Escitalopram to treat his residual depressive symptoms, namely insomnia and tiredness. Within two days he developed restlessness and unpleasant sensations in his legs which were worse at night. Symptom severity increased over the following days, prompting an urgent consultation a week later. The patient's presentation met the criteria for RLS. Agomelatine was discontinued leaving the patient on Escitalopram alone. The patient's symptoms improved within 24 h of stopping Agomelatine, with complete resolution four days later. There was no recurrence of RLS during follow-up. The patient scored 6 on Naranjo's adverse drug reaction probability scale, indicating a probable adverse drug reaction caused by Agomelatine.

CONCLUSIONS

To the best of our knowledge, this is the first case report of suspected Agomelatine-induced RLS. Clinicians need to be aware of RLS to enable prompt diagnosis and management. We suggest adding Agomelatine to the list of agents that can potentially induce RLS.

[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.

The DIalysis Symptom COntrol-Restless Legs Syndrome (DISCO-RLS) Trial: A Protocol for a Randomized, Crossover, Placebo-Controlled Blinded Trial

Background

Restless legs syndrome (RLS) affects approximately 30% of patients with end-stage kidney disease and is associated with impaired sleep and health-related quality of life. Medications used to treat RLS in patients receiving dialysis may have an increased risk of adverse events with dose titration, and residual RLS symptoms are common despite the use of effective treatments. Randomized controlled trials of monotherapy and combination pharmacologic therapy for RLS in hemodialysis are needed.

Objective

To perform a randomized, crossover, placebo-controlled blinded trial of pharmacologic therapy for RLS in hemodialysis.

Design/setting

The DIalysis Symptom COntrol-Restless Legs Syndrome (DISCO-RLS) trial is a randomized, crossover, placebo-controlled blinded trial of fixed low-dose pharmacologic therapy in patients receiving hemodialysis in 10 centers across Canada. It uses patient partners in its design, conduct, and reporting.

Participants

Adults receiving thrice-weekly hemodialysis for at least 3 months with RLS of at least mild symptoms defined International Restless Legs Syndrome Study Group Rating Scale (IRLS) of 10 or more will enter a double placebo run-in period to exclude nonadherent participants and those unable to tolerate double placebo. Seventy-two participants who completed the run-in period will be randomized to 1 of 8 treatment sequences based on modeling with 4 treatment periods.

Methods

Each treatment period lasts 4 weeks and consists of ropinirole 0.5 mg daily and gabapentin 100 mg daily, both together or neither with a double dummy placebo control for each treatment. The primary outcome is the difference in change scores of the IRLS between study treatments. Secondary outcomes are the differences in change scores of the Restless Legs Syndrome-6 Scale, patient global impression, 5-level EQ-5D version, and safety outcomes.

Results

This randomized, crossover, placebo-controlled blinded trial will evaluate the efficacy and safety of fixed low-dose combination of ropinirole and gabapentin in patients receiving hemodialysis with RLS.

Limitations

Patients with chronic kidney disease not on dialysis, kidney transplant recipients and those receiving peritoneal dialysis or home hemodialysis are not included. The intervention's long term safety and efficacy including the risk of augmentation is not captured.

Conclusion

This randomized crossover placebo controlled blinded trial will evaluate the efficacy and safety of fixed low-dose combination ropinirole and gabapentin in patients receiving hemodialysis with RLS.

Trial Registration

ClinicalTrials.gov (NCT03806530).

[Restless legs syndrome in Parkinson's disease]

Disturbances in sleep and wakefulness are important symptoms of Parkinson's disease (PD) and are associated with negative effects on patients' quality of life. The analysis of literature on the relationship between RLS and PD revealed three main hypotheses explaining the relatively high incidence of RLS in PD: (1) RLS can be considered as an early (prodromal) manifestation or a predictor of PD that can outpace its main symptoms by several years (by analogy with conduct disorder during sleep with REM); (2) the high incidence of RLS in the advanced stage of PD may be associated with augmentation of previously latent RLS symptoms during prolonged dopaminergic therapy of PD; (3) a significant proportion of RLS cases in PD patients are not «classical» RLS, but represent, for example, manifestations of motor or non-motor fluctuations or a special form of stereotypy in the legs. Further research is needed to determine if any of these statements are true.

Exploratory cross-over, trial of augmented RLS with the dopamine receptor 1/5 antagonist ecopipam D1/D5 antagonist ecopipam for augmented RLS

BACKGROUND

Restless legs syndrome (RLS) is a common condition that initially responds dramatically to dopaminergic therapy. Over time, however, dopaminergics cause augmentation, where symptoms occur earlier and intensify. Animal models suggest this may result from increased dopamine receptor type-1 affinity in the spinal cord. Ecopipam is a potent, specific dopamine-1/5 receptor antagonist.

METHODS

We performed a small (N = 10) exploratory placebo controlled, cross-over safety trial of ecopipam (25-100 mg/day) for patients with augmented RLS currently taking dopamine agonists.

RESULTS

Ecopipam was well tolerated with sedation being the most common adverse event in drug and placebo. Safety scales and serology data were similar to placebo. The study was not powered to demonstrate efficacy and exploratory efficacy data showed no significant improvement compared to placebo, but RLS diaries, the international RLS rating scale, and clinical global impressions all favored drug. No subject worsened on drug or demonstrated rebound worsening after drug discontinuation.

CONCLUSION

Ecopipam was safe and well tolerated in this initial study for RLS. Given the lack of alternate options, larger efficacy studies for augmented RLS, and potentially de novo RLS are justified.

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.

Magnesium supplementation for the treatment of restless legs syndrome and periodic limb movement disorder: A systematic review

Magnesium supplementation is often suggested for restless legs syndrome (RLS) or period limb movement disorder (PLMD) based on anecdotal evidence that it relieves symptoms and because it is also commonly recommended for leg cramps. We aimed to review all articles reporting the effects of magnesium supplementation on changes in RLS and/or PLMD. We conducted a systematic search looking for all relevant articles and then two reviewers read all article titles and abstracts to identify relevant studies. Eligible studies were scored for their quality as interventional trials. We found 855 abstracts and 16 of these could not be definitively excluded for not addressing all aspects of our research question. Seven full-text articles were unlocatable and one was ineligible which left eight studies with relevant data. One was a randomised placebo-controlled trial, three were case series and four were case studies. The RCT did not find a significant treatment effect of magnesium but may have been underpowered. After quality appraisal and synthesis of the evidence we were unable to make a conclusion as to the effectiveness of magnesium for RLS/PLMD. It is not clear whether magnesium helps relieve RLS or PLMD or in which patient groups any benefit might be seen.

Quantitative Comparison of the Efficacies of 5 First-Line Drugs for Primary Restless Leg Syndrome

Comparative analyses of the efficacies of dopaminergic agonists (pramipexole, ropinirole, and rotigotine patch) and α-2-δ ligands (gabapentin enacarbil and pregabalin) for treatment of primary restless leg syndrome (RLS) are lacking because of the few head-to-head clinical trials. A model-based meta-analysis approach was employed to quantitatively compare the efficacies of these 5 first-line RLS drugs. Longitudinal efficacy data of RLS drugs were collected from published eligible literature. Mean changes in both the International Restless Leg Syndrome Study Group (IRLS) rating scale and Clinical Global Impression Improvement (CGI-I) scale response rate were analyzed. A study-level population pharmacodynamic model was used to fit the dose-effect relationship and to describe the therapeutic effect over time for RLS drugs and placebo, and the typical efficacies of these drugs were compared. The onset of action was rapid for RLS drugs. In the placebo group, typical maximum IRLS reduction (E_max,IRLS ) and CGI-I response rate (E_max,CGI-I ) were -9.34 points and 48.2%, respectively. After deducting placebo effects, we found that the baseline IRLS score was significantly correlated with the E_max,IRLS of dopaminergic agonists. Typical E_max,IRLS of dopaminergic agonists was expressed as - 7.7 - 0.682 × ( baseline IRLS score - 24 ) points. Typical E_max,IRLS values of pregabalin and gabapentin enacarbil were -5.95 points and -4.00 points, respectively. The therapeutic effect of dopaminergic agonists was found to be associated with baseline symptom severity. In RLS patients with more severe symptoms, the therapeutic effect of dopaminergic agonists tended to be better than that of α-2-δ ligands.

The Effect of the Cool Dialysate on the Restless Leg Syndrome in Hemodialysis Patients: Randomized Triple-Blind Clinical Trial

Background

Restless leg syndrome (RLS) is a common symptom of some diseases specially observed during hemodialysis. Cooling the dialysate is a safe and nonpharmacological method. The aim of this study was to assess the effect of cool dialysate on RLS in hemodialysis patients.

Materials and Methods

A total of 79 patients were selected for screening based on the four main criteria set by the RLS International Association. Finally, in line with the inclusion and exclusion criteria, 63 hemodialysis patients were recruited and participated in this clinical trial. The patients were randomly assigned to the intervention group (n = 32) and the control group (n = 31). The intervention group received 35.5°C dialysate and the control group received 37°C dialysate three times a week for a period of 1 month. The severity of RLS was measured in both groups using a standardized RLS questionnaire. Using R software version 3.3.1, the data were analyzed using the Student's t-test, and Wilcoxon test, at 95% confidence interval.

Results

In terms of RLS severity, there was no significant difference between intervention and control groups before the intervention (t = -2.11, p > 0.05). After the intervention, the mean (SD) of RLS severity in the control group was 28.77 (5.45) and in the intervention group was 11.66 (4.69), in which t test showed a significant difference between two groups (t = 14.03, p= 0.001).

Conclusions

Using cool dialysate as a nonpharmacological treatment may reduce the severity of RLS in patients on hemodialysis. Therefore, using this method to improve RLS in hemodialysis patients is recommended.

Restless Legs Syndrome and Other Movement Disorders of Sleep-Treatment Update

PURPOSE OF REVIEW

The purpose of this review article is to summarize and discuss the recent advances in the treatment of restless legs syndrome (RLS), as well as REM sleep behavior disorder (RBD), and periodic leg movement disorder (PLMD).

RECENT FINDINGS

Traditionally, dopaminergic therapy has been considered the sole option for first-line treatment of RLS due to their impressive acute efficacy. Dopamine agonists such as oral pramipexole and ropinirole, as well as transdermal rotigotine are all effective treatment options. However, augmentation of the RLS symptoms is a major limitation of oral dopaminergic therapy. Recently, gabapentinoid agents such as gabapentin enacarbil and pregabalin have shown comparable short-term efficacy to dopaminergics with lower risk of augmentation of the RLS symptoms. Recent evidence on the efficacy of oxycodone-naloxone in treatment-resistant RLS provides an additional therapeutic avenue. The increasing understanding of the role of iron in RLS pathophysiology has led to new options in iron supplementation therapy in RLS, including treatment with ferric carboxymaltose. With emerging evidence of augmentation being a side effect specific to dopaminergic treatment, gabapentinoids are considered a safer option as initial treatment. In severe refractory RLS, oxycodone-naloxone can be used. If iron stores are low, IV iron formulations should be the initial treatment choice. New treatment options are needed to address issues with current therapies.

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.

The efficacy and tolerability of rotigotine on patients with periodic limb movement in sleep: A systematic review and meta-analysis

OBJECTIVE

There is still no consensus on the treatment for periodic limb movement in sleep (PLMS). This study aimed to determine the efficacy and tolerability of rotigotine in patients suffering from PLMS.

METHODS

Publications listed in PubMed, ScienceDirect, The Cochrane Library, and ClinicalTrials.gov were reviewed to assess the efficacy of rotigotine on PLMS. Analyses of PLMS frequency before and after rotigotine treatments (pre- and post-intervention studies) and PLMS frequency between placebo and rotigotine treatments (placebo-controlled trial studies) were included in our study. A systematic review and meta-analysis was conducted.

RESULTS

Five publications involving 197 participants were included in this study. Among these articles, pre- and post-intervention data involving 55 participants were available from three articles, while placebo-controlled trial data from 107 participants receiving rotigotine and 70 participants receiving a placebo were available from an additional three articles. In the pre- and post-intervention studies, the periodic limb movement index was significantly decreased after therapy with rotigotine with a difference in means of -5.866/h (95% CI, -10.570 to -1.162, p = 0.015). In comparison with the placebo, the use of rotigotine significantly lowered the periodic limb movement index, with a difference in means of -32.105/h (95% CI, -42.539 to -21.671, p < 0.001), reduced the PLMS with arousal index, with a difference in means of -7.160/h (95% CI, -9.310 to -5.010, p < 0.001), and increased the withdrawal rate, with an odds ratio of 3.421 (95% CI, 1.230 to 9.512, p = 0.018).

CONCLUSIONS

This meta-analysis revealed the considerable efficacy of rotigotine in alleviating the frequency of PLMS. However, the high withdrawal rate should be taken into account.

Use of α2δ Ligands for Restless Legs Syndrome/Willis Ekbom Disease

Restless legs syndrome is a common neurological condition affecting a substantial portion of the population. It can be an idiopathic disorder, or one that is secondary to another cause. Given that the underlying pathophysiology of restless legs syndrome is not well understood, several drug classes have been studied for symptom control. While dopamine agonists have long been the mainstay of first-line treatment for restless legs syndrome, recently, the α2δ ligands have been increasingly used. These agents have proven both efficacious and safe in a number of clinical trials. Additionally, compared with the dopamine agonists, they have been associated with less augmentation, a phenomenon whereby symptoms emerge earlier in the day, become more severe, and may spread to areas of the body previously unaffected. Newer clinical guidelines for restless legs syndrome are increasingly recommending the α2δ ligands as a logical first-choice medication for patients needing drug therapy for symptom control.

Restless Legs Syndrome: From Pathophysiology to Clinical Diagnosis and Management

Restless legs syndrome (RLS), a common neurological sensorimotor disorder in western countries, has gained more and more attention in Asian countries. The prevalence of RLS is higher in older people and females. RLS is most commonly related to iron deficiency, pregnancy and uremia. The RLS symptoms show a significant circadian rhythm and a close relationship to periodic limb movements (PLMs) in clinical observations, while the pathophysiological pathways are still unknown. The diagnostic criteria have been revised in 2012 to improve the validity of RLS diagnosis. Recent studies have suggested an important role of iron decrease of brain in RLS pathophysiology. Dopaminergic (DA) system dysfunction in A11 cell groups has been recognized long ago from clinical treatment and autopsy. Nowadays, it is believed that iron dysfunction can affect DA system from different pathways and opioids have a protective effect on DA system. Several susceptible single nucleotide polymorphisms such as BTBD9 and MEIS1, which are thought to be involved in embryonic neuronal development, have been reported to be associated with RLS. Several pharmacological and non-pharmacological treatment are discussed in this review. First-line treatments of RLS include DA agents and α2δ agonists. Augmentation is very common in long-term treatment of RLS which makes prevention and management of augmentation very important for RLS patients. A combination of different types of medication is effective in preventing and treating augmentation. The knowledge on RLS is still limited, the pathophysiology and better management of RLS remain to be discovered.

Erratum: Incidence of Augmentation in Primary Restless Legs Syndrome Patients May Not Be That High: Evidence From A Systematic Review and Meta-Analysis: Erratum

[This corrects the article DOI: 10.1097/MD.0000000000002504.].