A crossover study of gabapentin in treatment of restless legs syndrome among hemodialysis patients

Restless Legs Syndrome in Chronic Kidney Disease- a Systematic Review

Objectives

The objective of this review is to provide updated information on the epidemiology, correlating factors and treatment of chronic kidney disease associated restless legs syndrome (CKD-A-RLS) in both adult and pediatric population.

Materials and Methods

We have reviewed the Medline search and Google Scholar search up to May 2022, using key words restless legs syndrome, chronic kidney disease and hemodialysis and kidney transplant. The reviewed articles were studied for epidemiology, correlating factors, as well as pharmacologic and non-pharmacologic treatment options.

Results

Our search revealed 175 articles, 111 were clinical trials or cross- sectional studies and 64 were review articles. All 111 articles were retrieved and studied in detail. Of these, 105 focused on adults and 6 on children. A majority of studies on dialysis patients reported a prevalence between 15-30%, which is notably higher than prevalence of RLS in general population (5-10%). The correlation between presence of CKD-A-RLS with age, gender, abnormalities of hemogram, iron, ferritin, serum lipids, electrolytes and parathyroid hormones were also reviewed. The results were inconsistent and controversial. Limited studies have reported on the treatment of CKD-A-RLS. Non-pharmacological treatment focused on the effect(s) of exercise, acupuncture, massage with different oils and infra-red light whereas, pharmacologic treatment options include the effects of dopaminergic drugs, Alpha2-Delta ligands (gabapentin and pregabalin), vitamins E and C, and intravenous iron infusion.

Conclusion

This updated review showed that RLS is two to three times more common in patients with CKD compared to the general population. More patients with CKD-A-RLS demonstrated increased mortality, increased incidence of cardiovascular accident, depression, insomnia and impaired quality of life than those with CKD without RLS. Dopaminergic drugs such as levodopa, ropinirole, pramipexole and rotigotine as well as calcium channel blockers (gabapentin and pregabalin) are helpful for treatment of RLS. High quality studies with these agents are currently underway and hopefully confirm the efficacy and practicality of using these drugs in CKD-A-RLS. Some studies have shown that aerobic exercise and massage with lavender oil can improve symptoms of CKD-A- RLS suggesting that these measures can be useful as adjunct therapy.

Emerging Treatments for Insomnia, Sleep Apnea, and Restless Leg Syndrome Among Dialysis Patients

Sleep disturbances are highly prevalent in patients with predialysis chronic kidney disease, end-stage kidney disease, and after a kidney transplant. They contribute to impairment in daily function and are associated with a high burden of physical and psychiatric symptoms, decreased quality of life, and increased morbidity and mortality. Sleep disturbances also may precipitate and accelerate kidney disease progression. They often evolve across the spectrum of kidney dysfunction and may persist or re-emerge in kidney transplant recipients. Investigation into the multifaceted and dynamic relationships between sleep disturbance and chronic kidney disease requires consideration of myriad contributors including the progression of kidney disease itself, the role of treatment via dialysis and kidney transplant, psychosocial factors, and underlying sleep disorders. Despite sleep disturbance being identified as a priority to address by patients and caregivers, sleep disorders including insomnia, sleep apnea, and restless leg syndrome remain under-recognized and undertreated, and innovation in their management remains modest. In this article, we review the relationships between sleep disturbance and kidney disease, the impact of sleep disturbance and sleep disorders on symptom burden and mental health, and treatment opportunities that may address overlapping symptoms across the spectrum of kidney disease and that could improve patient-related and clinical outcomes.

Pharmacologic Treatment of Restless Legs Syndrome

Restless legs syndrome (RLS)/Willis-Ekbom disease is a neurologic disorder characterized by a strong desire to move when at rest (usually in the evening) and paraesthesia in their lower legs. The most widely used therapies for first-line treatment of RLS are dopaminergic drugs; however, their long-term use can lead to augmentation. α2δ Ligands, opioids, iron, glutamatergic drugs, adenosine, and sleep aids have been investigated as alternatives. The pathogenesis of RLS is not well understood. Despite the efficacy of dopaminergic drugs in the treatment of this disorder, unlike in Parkinson’s disease dopaminergic cell loss in the substantia nigra has not been observed in RLS. The etiology of RLS is likely complex, involving multiple neural pathways. RLS-related genes identified in genome-wide association studies can provide insight into the mechanistic basis and pathophysiology of RLS. Here we review the current treatments and knowledge of the mechanisms underlying RLS.

Restless Legs Syndrome: Contemporary Diagnosis and Treatment

Restless legs syndrome (RLS) is characterized by an uncomfortable urge to move the legs while at rest, relief upon movement or getting up to walk, and worsened symptom severity at night. RLS may be primary (idiopathic) or secondary to pregnancy or a variety of systemic disorders, especially iron deficiency, and chronic renal insufficiency. Genetic predisposition with a family history is common. The pathogenesis of RLS remains unclear but is likely to involve central nervous system dopaminergic dysfunction, as well as other, undefined contributing mechanisms. Evaluation begins with a thorough history and examination, and iron measures, including ferritin and transferrin saturation, should be checked at presentation and with worsened symptoms, especially when augmentation develops. Augmentation is characterized by more intense symptom severity, earlier symptom occurrence, and often, symptom spread from the legs to the arms or other body regions. Some people with RLS have adequate symptom control with non-pharmacological measures such as massage or temperate baths. First-line management options include iron-replacement therapy in those with evidence for reduced body-iron stores or, alternatively, with prescribed gabapentin or pregabalin, and dopamine agonists such as pramipexole, ropinirole, and rotigotine. Second-line therapies include intravenous iron infusion in those who are intolerant of oral iron and/or those having augmentation with intense, severe RLS symptoms, and opioids including tramadol, oxycodone, and methadone. RLS significantly impacts patients' quality of life and remains a therapeutic area sorely in need of innovation and a further pipeline of new, biologically informed therapies.

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).

Movement Disorders in Chronic Kidney Disease - A Descriptive Review

OBJECTIVES

The objective of this study is to describe the mechanism of damage to subcortical structures in chronic kidney disease (CKD) and to describe the range of movement disorders associated with CKD.

MATERIALS AND METHODS

We have reviewed the Medline literature up to January of 2020 using key words movement disorders and chronic kidney disease. The reviewed articles were studied for mechanisms of subcortical damage in CKD as well as type of the reported movements, their frequency and updated treatment.

RESULTS

The search revealed 183 articles most of them dealing with restless legs syndrome. The damage to basal ganglia in CKD resulted from several mechanisms including accumulation of nitro tyrosine caused by reactive oxygen species and action of uremic toxins leading to endothelial damage and dysfunction of blood-brain barrier. Involuntary movements in CKD include restless legs syndrome (RLS), myoclonus, asterixis, dystonia, chorea, tremor, and Parkinsonism.

CONCLUSIONS

Chronic kidney disease can cause several abnormal involuntary movements via damaging basal ganglia and subcortical structures. The most common movement disorders in CKD are RLS, myoclonus and asterixis. Restless legs syndrome and myoclonus when severe, need and respond to treatment. Movement disorders in CKD improve with improvement of kidney function.

Cannabis Use for Restless Legs Syndrome and Uremic Pruritus in in patients treated with maintenance dialysis: A Survey

Background:

Restless legs syndrome (RLS) and uremic pruritus reduce the quality of life in patients with end-stage kidney disease (ESKD) and current treatments are often insufficient. There is an increasing interest in using cannabinoids for symptom management, and preliminary evidence suggests cannabinoids may help alleviate RLS and pruritus.

Objectives:

(1) To assess the frequency and severity of RLS and pruritus in our ESKD population with the current treatment options, (2) to estimate patient use of cannabinoids for these symptoms, and (3) to determine interest in participating in future trials to treat RLS and/or pruritus.

Design:

Survey.

Patients:

Adult prevalent patients with ESKD treated with dialysis at the Ottawa Hospital.

Measurements:

International RLS Study Group Rating Scale and visual analogue scale for symptom severity of RLS and pruritus, respectively.

Methods:

Eligible patients with ESKD treated at the Ottawa Hospital were invited to complete a survey to identify symptoms and severity of RLS and pruritus using validated scales, cannabis use for management, and interest in future trials. Basic demographic statistics to describe the study population and results were used.

Results:

Sixty-nine percent (192 of 277) of eligible patients completed the surveys, 35 declined participation, and 50 surveys were not returned. Eighty-six (45%) and 129 patients (67%) reported symptoms of RLS and pruritus, respectively. Only 18 previously symptomatic patients were relieved with current treatment. Fifteen patients reported cannabis use for symptoms; 9 noted improvement. Most (>2 of 3) symptomatic patients were interested in participating in a future trial.

Limitations:

Single-center study in a tertiary-care hospital in Canada limiting generalizability. Quoted prevalence of symptoms is dependent on survey return.

Conclusions:

A large proportion of ESKD patients suffer from RLS and/or pruritus, most of which are not relieved by existing treatments. Few patients reported trying cannabis to decrease their symptoms despite legalization. This study confirms strong patient interest for future trials regarding cannabis for symptom relief.

Trial Registration:

Not applicable.

Dialysis Patients With Restless Leg Syndrome: Can We Relieve Their Suffering?

Restless leg syndrome (RLS), also called Willis Ekbom disease, can be described as an unpleasant feeling that intensely urges the patients to move their lower limbs. RLS is classified into primary and secondary. It is one of the common complications in hemodialysis patients, and it impairs patients’ quality of life. Unfortunately, it is an underdiagnosed and undertreated disorder. In this review article, we performed a literature search using the PubMed database to compare different treatment modalities for RLS in patients with end-stage renal disease (ESRD) on regular hemodialysis. Many of the non-pharmacologic modalities of treatment are cost-effective and safer than pharmacologic therapy. Given the small sample size of the studies and short follow up duration, we should consider conducting studies on a larger number of patients and for longer periods of time to assess the efficacy and safety of different treatment patterns for RLS in hemodialysis patients. We hope to raise awareness about this neurologic condition in hemodialysis patients.

Comparative efficacy and acceptability of treatments for restless legs syndrome in end-stage renal disease: a systematic review and network meta-analysis

Background

Restless legs syndrome (RLS) is common in end-stage renal disease (ESRD) patients and impairs health and quality of life significantly. However, the optimal treatment of RLS in ESRD patients is uncertain and less studied compared with idiopathic RLS patients.

Methods

We conducted a systematic review and network meta-analysis to compare the efficacy and acceptability of treatments for RLS in ESRD patients. Randomized controlled trials (RCTs) by February 2019 in the PubMed, Cochrane Library, Embase and ClinicalTrials.gov were reviewed. RLS severity reduction was treated as treatment efficacy, and adverse events were treated as acceptable. Both outcomes were appraised using a random effects model expressed as standardized mean differences and odds ratios with 95% confidence intervals (CIs), respectively, and were ranked using surface under the cumulative ranking curve (SUCRA) probabilities to obtain a hierarchy of interventions.

Results

A total of 12 RCTs were included, comprising 9 interventions and 498 participants. All the interventions significantly improved RLS severity without critical side effects compared with placebo. Gabapentin achieved the greatest decrease of RLS severity [standardized mean difference (SMD) = 1.95, 95% CI 0.81–3.09 (SUCRA: 79.3%)], despite its frequent adverse events [SMD = 0.18, 95% CI 0.02–1.50 (19.9%)]. The combination therapy of exercise plus dopamine agonist had better efficacy [SMD = 1.60, 95% CI 0.08–3.12 (59.8%)] and acceptability [SMD = 1.41, 95% CI 0.01–142.53 (63.9%)] compared with that of vitamin C plus vitamin E [SMD = 1.50, 95% CI 0.47–2.54 (56.6%); SMD = 0.32, 95% CI 0.04–2.86 (32.5%)].

Conclusions

This network meta-analysis supports that gabapentin is the most effective treatment for RLS in ESRD patients. Exercise plus dopamine agonist is a favorable combination therapy concerning side effects. Future large RCTs with long-term treatment outcomes are necessary.

Gabapentin for Off-Label Use: Evidence-Based or Cause for Concern?

Gabapentin is widely used in the United States for a number of off-label indications, often as an alternative to opioid therapy. Increasing evidence has emerged suggesting that gabapentin may not be as benign as once thought and may be associated with substance abuse in concert with opioids. With concerns for safety mounting, it is prudent to examine the efficacy of gabapentin across its many uses to understand the risk-benefit balance. Reviews on off-label indications such as migraine, fibromyalgia, mental illness, and substance dependence have found modest to no effect on relevant clinical outcomes. This high-quality evidence has often been overshadowed by uncontrolled studies and limited case reports. Furthermore, the involvement of gabapentin in questionable marketing schemes further calls its use into question. Overall, clinicians should exercise rigorous appraisal of the available evidence for a given indication, and researchers should conduct larger, higher-quality studies to better assess the efficacy of gabapentin for many of its off-label uses.

Gabapentin and Pregabalin Use and Association with Adverse Outcomes among Hemodialysis Patients

Background Gabapentin and pregabalin are used to manage neuropathic pain, pruritus, and restless legs syndrome in patients on hemodialysis. These patients may be especially predisposed to complications related to these agents, which are renally cleared, but data regarding the risk thereof are lacking.Methods From the US Renal Data System, we identified 140,899 Medicare-covered adults receiving hemodialysis with Part D coverage in 2011. Using Cox regression models in which we adjusted for demographics, comorbidities, duration of exposure, number of medications, and use of potentially confounding concomitant medications, we investigated the association between gabapentin and pregabalin, modeled as separate time-varying exposures, and time to first emergency room visit or hospitalization for altered mental status, fall, and fracture. We evaluated risk according to daily dose categories: gabapentin (>0-100, >100-200, >200-300, and >300 mg) and pregabalin (>0-100 and >100 mg).Results In 2011, 19% and 4% of patients received gabapentin and pregabalin, respectively. Sixty-eight percent of gabapentin or pregabalin users had a diagnosis of neuropathic pain, pruritus, or restless legs syndrome. Gabapentin was associated with 50%, 55%, and 38% higher hazards of altered mental status, fall, and fracture, respectively, in the highest dose category, but even lower dosing was associated with a higher hazard of altered mental status (31%-41%) and fall (26%-30%). Pregabalin was associated with up to 51% and 68% higher hazards of altered mental status and fall, respectively.Conclusions Gabapentin and pregabalin should be used judiciously in patients on hemodialysis, and research to identify the most optimal dosing is warranted.

Sleep disorders in dialysis patients

Poor sleep and sleep-related breathing disorders are common in patients with end-stage renal disease (ESRD) but are often unrecognized and undertreated. Sleep disorders are known negative prognostic factors for morbidity and mortality. The most frequent sleep disorders seen in patients with ESRD are conditioned insomnia, excessive daytime sleepiness, obstructive or central sleep apnea (SA), as well as restless legs syndrome (RLS) and periodic limb movement disorder (PLMD). Several uremic and nonuremic factors are thought to participate in the pathogenesis of sleep disorders in patients with ESRD. The therapy of sleeping disorders includes nonpharmacological and pharmacological measures that can improve the functionality and quality of life in patients with ESRD.

Clinical management of restless legs syndrome in end-stage renal disease patients

Restless legs syndrome (RLS) is a common neurological movement disorder, characterized by restless and unpleasant sensations in the deep inside of legs. The symptoms of RLS are less noticeable during daytime, but more prevalent at night. Therefore, the disorder can induce low quality of life, insomnia, and impairment of daytime activity. RLS in end-stage renal disease (ESRD) patients is especially problematic due to premature discontinuation of dialysis and increased mortality. The prevalence of RLS among dialysis patients is much higher compared to the prevalence of the same disorder in patients with normal renal functions. Even though there are recommended treatment guidelines for the general population established by Medical Advisory Board of the RLS foundation, which include the use of dopamine agonists, levodopa, gabapentin, benzodiazepines, and opioids, limited information is available on the effects of these therapies in ESRD patients. Since the existing clinical data were extrapolated from small sample sizes in short-term clinical trials, further clinical studies are still needed to better assess the efficacy, safety, and tolerability of these medications in patients with ESRD.

Interventions for chronic kidney disease-associated restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) is defined as the spontaneous movement of the limbs (mainly legs) associated with unpleasant, sometimes painful sensation which is relieved by moving the affected limb. Prevalence of RLS among people on dialysis has been estimated between 6.6% and 80%. RLS symptoms contribute to impaired quality of life and people with RLS are shown to have increased cardiovascular morbidity and mortality.Various pharmacological and non-pharmacological interventions have been used to treat primary RLS. However, the evidence for use of these interventions in people with chronic kidney disease (CKD) is not well established. The agents used in the treatment of primary RLS may be limited by the side effects in people with CKD due to increased comorbidity and altered drug pharmacokinetics.

OBJECTIVES

The aim of this review was to critically look at the benefits, efficacy and safety of various treatment options used in the treatment of RLS in people with CKD and those undergoing renal replacement therapy (RRT). We aimed to define different group characteristics based on CKD stage to assess the applicability of a particular intervention to an individual patient.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register to 12 January 2016 through contact with the Information Specialist using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials (RCT) and quasi-RCTs that assessed the efficacy of an intervention for RLS in adults with CKD were eligible for inclusion. Studies investigating idiopathic RLS or RLS secondary to other causes were excluded.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility and conducted risk of bias evaluation. Results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes.

MAIN RESULTS

We included nine studies enrolling 220 dialysis participants. Seven studies were deemed to have moderate to high risk of bias. All studies were small in size and had a short follow-up period (two to six months). Studies evaluated the effects of six different interventions against placebo or standard treatment. The interventions studied included aerobic resistance exercise, gabapentin, ropinirole, levodopa, iron dextran, and vitamins C and E (individually and in combination).Aerobic resistance exercise showed a significant reduction in severity of RLS compared to no exercise (2 studies, 48 participants: MD -7.56, 95% CI -14.20 to -0.93; I² = 65%), and when compared to exercise with no resistance (1 study, 24 participants: MD -11.10, 95% CI -17.11 to -5.09), however there was no significant reduction when compared to ropinirole (1 study, 22 participants): MD -0.55, 95% CI -6.41 to 5.31). There were no significant differences between aerobic resistance exercise and either no exercise or ropinirole in the physical or mental component summary scores (using the SF-36 form). Improvement in sleep quality varied. There was no significant difference in subjective sleep quality between exercise and no exercise; however one study reported a significant improvement with ropinirole compared to resistance exercise (MD 3.71, 95% CI 0.89 to 6.53). Using the Epworth Sleepiness Scale there were no significant differences between resistance exercise and no exercise, ropinirole, or exercise with no resistance. Two studies reported there were no adverse events and one study did not mention if there were any adverse events. In one study, one patient in each group dropped out but the reason for dropout was not reported. Two studies reported no adverse events and one study did not report adverse events.Gabapentin was associated with reduced RLS severity when compared to placebo or levodopa, and there was a significant improvement in sleep quality, latency and disturbance reported in one study when compared to levodopa. Three patients dropped out due to lethargy (2 patients), and drowsiness, syncope and fatigue (1 patient).Because of a short duration of action, rebound and augmentation were noted with levodopa treatment even though it conferred some benefit in reducing the symptoms of RLS. Reported adverse events were severe vomiting, agitation after caffeine intake, headaches, dry mouth, and gastrointestinal symptoms.One study (25 participants) reported iron dextran reduced the severity of RLS at weeks one and two, but not at week four. Vitamins C, E and C plus E (1 study, 60 participants) helped the symptoms of RLS with minimal side effects (nausea and dyspepsia) but more evidence is needed before any conclusions can be drawn.

AUTHORS' CONCLUSIONS

Given the small size of the studies and short follow-up, it can only be concluded that pharmacological interventions and intra-dialytic exercise programs have uncertain effects on RLS in haemodialysis patients. There have been no studies performed in non-dialysis CKD, peritoneal dialysis patients, or kidney transplant recipients. Further studies are warranted before any conclusions can be drawn. Aerobic resistance exercise and ropinirole may be suitable interventions for further evaluation.

Prevalence of restless legs syndrome during detoxification from alcohol and opioids

BACKGROUND AND AIMS

Restless legs syndrome (RLS) is a movement disorder associated with adverse health outcomes and decreased quality of life. Small case series suggest that symptoms of RLS occur during opioid withdrawal. However, the prevalence is unknown.

METHODS

We conducted an observational study to determine the prevalence of RLS among inpatients patients receiving buprenorphine detoxification from opioids. To assess the specificity of RLS to opioid detoxification, we also evaluated patients receiving detoxification from alcohol as a comparison group. The diagnosis of RLS was established using a validated questionnaire.

RESULTS

The sample consisted of 124 adults with primary opioid use disorder and 180 with primary alcohol use disorder. In the total sample, 33.6% met a likely RLS diagnosis: 50.8% of those with opioid use disorder and 21.7% of those with alcohol use disorder (χ² = 27.96[1,304] p < .001). In the logistic regression analysis controlling for socio-demographic and clinical variables, diagnosis of opioid use disorder was associated with more than twice the likelihood of RLS diagnosis (OR=2.05, 95% CI 1.09-3.88) relative to diagnosis of alcohol use disorder.

CONCLUSIONS

Approximately half of patients undergoing inpatient opioid detoxification exhibited the symptoms characteristic of RLS. We believe that these data support the existence of a secondary form of RLS associated with opioid withdrawal.

Sleep Disorders, Restless Legs Syndrome, and Uremic Pruritus: Diagnosis and Treatment of Common Symptoms in Dialysis Patients

Maintenance dialysis patients experience a high burden of physical and emotional symptoms that directly affect their quality of life and health care utilization. In this review, we specifically highlight common troublesome symptoms affecting dialysis patients: insomnia, restless legs syndrome, and uremic pruritus. Epidemiology, pathophysiology, and evidence-based current treatment are reviewed with the goal of providing a guide for diagnosis and treatment. Finally, we identify multiple additional areas of further study needed to improve symptom management in dialysis patients.

Restless Legs Syndrome in Patients With Chronic Kidney Disease

Symptoms of restless legs syndrome (RLS) are common in patients with chronic kidney disease (CKD) on dialysis; symptoms of RLS are estimated to affect up to 25% of patients on dialysis when the international RLS diagnostic criteria are applied. RLS is a neurologic disorder with a circadian rhythmicity characterized by an overwhelming urge to move the legs during rest, which can be relieved temporarily by movement. RLS has been associated with an increase in sleep disturbance, higher cardiovascular morbidity, decreased quality of life, and an increased risk of death in patients with CKD. Although the exact pathophysiology of RLS is unknown, it is thought to involve an imbalance in iron metabolism and dopamine neurotransmission in the brain. The symptoms of moderate to severe RLS can be treated with several pharmacologic agents; however, data specific to patients on dialysis with RLS are lacking. The purpose of this article is to examine the relationship between, and complications of, RLS and CKD both in dialysis and nondialysis patients, and discuss the treatment options for patients on dialysis with RLS.

[Sleep and sleep disorders in the elderly: Part 3: Restless legs syndrome]

Restless legs syndrome (RLS) is a commonly occurring condition with a prevalence of approximately 10%. Women are more often affected than men. There is a primary and a secondary form. Secondary RLS is triggered by iron deficiency, severe renal insufficiency and many drugs and medications. The treatment for RLS is always symptomatic. In addition to treating associated diseases, dopaminergic therapy is paramount. Pharmacotherapy encompasses levodopa (L-dopa) and dopamine agonists, such as pramipexole, ropinirole and rotigotine. A serious complication of dopaminergic therapy is the so-called augmentation. In the case of insufficient efficacy, severe discomfort or augmentation, oxycodone/naloxone is now approved for the treatment of RLS.

Efficacy and safety of gabapentin for uremic pruritus and restless legs syndrome in conservatively managed patients with chronic kidney disease

CONTEXT

Pruritus and restless legs syndrome (RLS) frequently affect patients with chronic kidney disease (CKD) and end-stage kidney disease (ESKD), impacting the quality of life. Gabapentin (1-aminomethyl cyclohexane acetic acid) alleviates these symptoms in hemodialysis (HD) patients, but data are lacking for patients on the conservative pathway.

OBJECTIVES

To determine the safety and effectiveness of gabapentin for pruritus or RLS in conservatively managed patients (n = 34) with CKD and ESKD.

METHODS

This was a single-center retrospective cohort study. We compared dosing and side effects in 34 CKD/ESKD patients with similar patients receiving HD (n = 15).

RESULTS

Forty-four percent of conservatively managed patients complained of RLS and/or pruritus; 18% were excluded for a nonuremic cause of symptom. Thirty-four patients were included in the final analysis. The most common starting daily dose of gabapentin was the equivalent of 50 mg (44.1%) or 100 mg (38.2%) daily, with the median daily dose of 100 mg (range 39-455 mg). Side effects occurred in 47% of patients, with 17% discontinuing gabapentin. Gabapentin reduced symptoms of pruritus (P < 0.001) and RLS (P < 0.05). There was no statistical difference when comparing HD and conservatively managed patients for daily starting dose (P = 0.88), median dose (P = 0.84), and final dose (P = 0.18). Patients conservatively managed were more likely to manifest side effects compared with HD patients (47.1% vs. 14.3%, P = 0.023). Dose was not found to be a factor associated with side effects in univariate analysis.

CONCLUSION

Gabapentin is a viable treatment for conservatively managed CKD and ESKD patients with pruritus and/or RLS, but side effects are common. Gabapentin should be used with caution although higher doses do not appear to be a factor associated with side effects.

Sleep disorders in chronic obstructive pulmonary disease: etiology, impact, and management

ABSTRACT

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality and may frequently be complicated by sleep disorders. Insomnia and obstructive sleep apnea are commonly encountered in patients with COPD. Nocturnal hypoxemia is also prevalent in COPD may occur despite adequate awake oxygenation and can be especially severe in rapid eye movement sleep. Additionally, several factors--some of them unique to COPD--can contribute to sleep-related hypoventilation. Recognition of hypoventilation can be vital as supplemental oxygen therapy itself can acutely worsen hypoventilation and lead to disastrous consequences. Finally, accruing data establish an association between restless leg syndrome and COPD--an association that may be driven by hypoxemia and/or hypercapnia. Comorbid sleep disorders portend worse sleep quality, diminished quality of life, and multifarious other adverse consequences. The awareness and knowledge regarding sleep comorbidities in COPD has continued to evolve over past many years. There are still several lacunae, however, in our understanding of the etiologies, impact, and therapies of sleep disorders, specifically in patients with COPD. This review summarizes the latest concepts in prevalence, pathogenesis, diagnosis, and management of diverse sleep disorders in COPD.

Brazilian consensus on guidelines for diagnosis and treatment for restless legs syndrome

The Consensus on restless legs syndrome is an effort of neurologists from several Brazilian states, which tirelessly reviewed the literature of recent years in search of evidence, both in regard to diagnosis and treatment, according to the Oxford Centre for Evidence-based Medicine.

Gabapentin enacarbil for the treatment of moderate to severe primary restless legs syndrome (Willis-Ekbom disease): 600 or 1,200 mg dose?

Gabapentin enacarbil is a prodrug of the anticonvulsant gabapentin. The efficacy and safety of gabapentin enacarbil for the treatment of moderate to severe primary restless legs syndrome (RLS) has been evaluated in several clinical trials in the United States and Japan. Although most clinical trials assessed gabapentin enacarbil at doses greater than 600 mg/day and demonstrated the overall safety and efficacy (defined as improvements in the coprimary endpoints of the international RLS rating scale [IRLS] total score and Clinical Global Impression-Improvement response), the US Food and Drug Administration approved the 600 mg once-daily dosage because doses higher than 600 mg/day were considered to provide no additional benefits and were associated with higher rates of adverse events, such as somnolence and dizziness. Nonetheless, the results of clinical trials and post hoc meta-analyses have indicated that the 1,200 mg once-daily dosage was the most validated gabapentin enacarbil treatment for not only subjective RLS symptoms but also severe sleep disturbance associated with RLS. A Japanese dose-finding study showed that 900 mg/day, the intermediate dose between 600 and 1,200 mg, failed to show a significant improvement in IRLS total score, probably because many of the patients who discontinued treatment did so early, suggesting that a half-landing dose may cause more adverse effects than favorable ones in some RLS patients early in the treatment. Gabapentin enacarbil may have two distinct therapeutic doses for the treatment of RLS: 600 mg/day or lower doses for the treatment of subjective RLS symptoms and 1,200 mg/day or higher doses for the treatment of both subjective RLS symptoms and associated problems such as severe sleep disturbances.

Epidemiology, impact, and treatment options of restless legs syndrome in end-stage renal disease patients: an evidence-based review. Kidney Int. 2014;85:1275-1282. [PMID: 24107848 DOI: 10.1038/ki.2013.394]

Restless legs syndrome (RLS) (or Willis-Ekbom disease) is a neurological disorder with high prevalence among the end-stage renal disease population. This is one of the most predominant types of secondary RLS, and it is called uremic RLS. Despite the fact that uremic RLS has been less studied compared to idiopathic RLS, recent studies now shed light in many aspects of the syndrome including clinical characteristics, impact, epidemiology, and treatment options. The current review discusses the above topics with special emphasis given on the management of uremic RLS, including the management of symptoms that often appear during a hemodialysis session. Uremic RLS symptoms may be ameliorated by using pharmacological and nonpharmacological treatments. Evidence so far shows that both approaches may be effective in terms of reducing the RLS symptom's severity; nevertheless, more research is needed on the efficiency of treatments for uremic RLS.

Restless legs syndrome: pathophysiology and modern management

Restless legs syndrome (RLS) is a common sensory motor neurological disorder that is characterised by an irresistible urge to move the legs that significantly affects the quality of life of the patient. Prevalence in the general population is 5-25% and it is twice as prevalent in women as in men. RLS is the most common movement disorder in pregnancy with a fourfold increased risk of developing this disorder later in life. The pathophysiology of RLS is centred on dopaminergic dysfunction, reduced central nervous system iron, genetic linkages, or alteration in neurotransmitters such as hypocretins, endorphins levels and immune dysfunction and inflammatory mechanisms. With the emergence of new evidence, there are changes to the previous treatment recommendations for RLS. There is sufficient evidence to conclude that dopamine agonists such as rotigotine transdermal patch, pramipexole, ropinirole, gabapentin enacarbil, pregabalin and gabapentin are effective in the short-term treatment of RLS and rotigotine, followed by gabapentin enacarbil, ropinirole, pramipexole and gabapentin for long-term treatment. Based on expert consensus, the recommendation for daily RLS is dopamine agonists or gabapentin or low-potency opioids. Levodopa is less preferred for treating daily RLS due to its high risk of augmentation. For intermittent RLS, it is levodopa or dopamine agonists or low-potency opioids or benzodiazepines. For refractory RLS, the choice is to change to gabapentin or a different dopamine agonist, addition of a second agent like gabapentin or benzodiazepine to the existing drug or changing to a high-potency opioid or tramadol. Medications with safety record in pregnancy include opioids and antiepileptics such as carbamazepine and gabapentin. There are concerns that patients with RLS are at risk for metabolic deregulation, autonomic dysfunction and cardiovascular morbidity. However, a recent study concluded that RLS is not associated with increased risk of cardiovascular complications.

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.

Diagnosis and treatment of sleep disorders: a brief review for clinicians

Sleep disorders encompass a wide spectrum of diseases with significant individual health consequences and high economic costs to society. To facilitate the diagnosis and treatment of sleep disorders, this review provides a framework using the International Classification of Sleep Disorders, Primary and secondary insomnia are differentiated, and pharmacological and nonpharmacological treatments are discussed. Common circadian rhythm disorders are described in conjunction with interventions, including chronotherapy and light therapy. The diagnosis and treatment of restless legs syndrome/periodic limb movement disorder is addressed. Attention is focused on obstructive sleep apnea and upper airway resistance syndrome, and their treatment. The constellation of symptoms and findings in narcolepsy are reviewed together with diagnostic testing and therapy, Parasomnias, including sleep terrors, somnambulism, and rapid eye movement (REM) behavior sleep disorders are described, together with associated laboratory testing results and treatment.

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

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

Long-term efficacy and safety of gabapentin enacarbil in Japanese restless legs syndrome patients

Several short- and long-term studies conducted in Europe/North America have demonstrated good efficacy and tolerability of 600-1800 mg gabapentin enacarbil (GEn). However, no studies have evaluated the efficacy of long-term treatment with GEn in Asian patients. Therefore, the objective of this study was to evaluate the efficacy and safety of long-term treatment with GEn in Japanese patients with restless legs syndrome (RLS) in a multicenter open-label study. RLS patients aged 20-80 years were allocated to receive oral GEn 1200 mg/day for a treatment period of 52 weeks. International Restless Legs Syndrome Scale (IRLS) score, investigator- and patient-rated Clinical Global Impression (CGI) scores, Pittsburgh Sleep Quality Index (PSQI) total scores and subscores, and short form (SF)-36 subscores were assessed, and adverse events (AEs) were monitored. In 181 patients (mean age, 54.9±12.2 years; BMI, 23.0±2.6 kg/m²) IRLS score decreased from 24.4±0.4 at baseline to 6.3±0.6 at week 52, with a reduction of -18.0±0.6. The IRLS responder rate was 80.3% at week 52. ICGI and PCGI responder rates were 87.1% and 87.1%, respectively. PSQI and SF-36 also showed significant improvements. AEs were reported in 96.2% of patients but remained mild-to-moderate in nearly all the cases. Serious AEs occurred in 1.6%. Dizziness and somnolence were noted in 46.2% and 41.2% of patients, respectively, and mostly occurred during the first 4 weeks. No episodes of augmentation were reported. In conclusion, long-term treatment with GEn improved RLS symptoms as well as investigator- and patient-reported outcomes in Japanese patients with moderate-to-severe RLS, with an acceptable safety profile. Randomized, double-blind, placebo/active-controlled trials are desirable to confirm these preliminary results.

Restless leg syndrome: is it a real problem?

Restless legs syndrome (RLS) is a common condition that is frequently unrecognized, misdiagnosed and poorly managed. It is characterized by uncomfortable sensations deep in the legs developing at rest that compel the person to move; symptoms are worst at night and sleep disturbance is common. RLS occurs in 7%-11% of the population in Western countries, and many such people experience troublesome symptoms. Primary RLS is familial in up to two thirds of patients. RLS may also be secondary to a number of conditions including iron deficiency, pregnancy and end-stage renal failure and, perhaps, neuropathy. Secondary RLS is most common in those presenting for the first time in later life. The pathogenesis of RLS probably involves the interplay of systemic or brain iron deficiency and impaired dopaminergic neurotransmission in the subcortex of the brain. RLS is very responsive to dopaminergic therapies. Rebound of RLS symptoms during the early morning and development of severe symptoms earlier in the day (augmentation) are problematic in those treated for a prolonged period with levodopa. Consequently, dopamine agonists have become first line treatment. Anti-convulsant medications and opioids are helpful in some patients. Correction of underlying problem wherever possible is important in the management of secondary RLS.

Gabapentin enacarbil - clinical efficacy in restless legs syndrome

Restless legs syndrome (RLS) is a sleep-related movement disorder commonly involving an unpleasant urge to move the limbs, typically the legs. Dopaminergic agents represent the first-line therapy for RLS; however, long-term use of such drugs results in worsening symptoms due to "augmentation" or other adverse events. Gabapentin, an analog of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), is an anticonvulsant/analgesic agent. Gabapentin is only mildly effective in relieving RLS symptoms, perhaps a result of its poor absorption from the gastrointestinal (GI) tract. Gabapentin enacarbil is a prodrug of gabapentin specifically designed to enhance absorption via the GI tract, and hence provide improved circulating levels of gabapentin on metabolism. Clinical trials to date have demonstrated favorable safety and (compared to traditional gabapentin) improved pharmacokinetics and efficacy in treating RLS symptoms. Thus, gabapentin enacarbil may prove to be a useful drug in treating RLS. An application of gabapentin enacarbil for treatment of RLS is currently pending with FDA for approval.

Gabapentin enacarbil in restless legs syndrome: a phase 2b, 2-week, randomized, double-blind, placebo-controlled trial

OBJECTIVES

Assess the efficacy and tolerability of gabapentin enacarbil (GEn), a transported prodrug of gabapentin with improved gabapentin exposure, in adults with moderate-to-severe primary restless legs syndrome.

METHODS

This 14-day, double-blind, randomized, controlled trial of GEn at 1200 or 600 mg or placebo taken once daily, evaluated the mean change from baseline International Restless Legs Scale (IRLS) total score at end of treatment (day 14:primary comparison, GEn at 1200 mg vs placebo). Secondary end points included Clinical Global Impression-Improvement scale outcomes at day 14.

RESULTS

Ninety-five subjects were randomized (GEn: 1200 mg, n = 33 and 600 mg, n = 29; placebo, n = 33); 2 subjects (GEn at 1200 mg) withdrew because of adverse events. At day 14,the mean (SD) change from baseline IRLS total score was significantly greater with GEn at 1200 mg (-16.1 [7.93]) compared with placebo (-8.9 [7.72]; adjusted mean treatment difference, -7.2; P < 0.0001). Investigator-rated Clinical Global Impression-Improvement scale responses also significantly favored GEn at 1200 mg compared with placebo (P G 0.0001).The mean (SD) change from baseline IRLS total score with GEn at 600 mg at day 14 was -9.1 (5.95), similar to placebo. The most commonly reported treatment-emergent adverse events were somnolence (GEn: 1200 mg, 36% and 600 mg, 14%; placebo,15%) and dizziness (GEn: 1200 mg, 18% and 600 mg, 14%; placebo, 3%), most of which were rated mild or moderate in intensity.

CONCLUSIONS

Gabapentin enacarbil at 1200 mg significantly improved restless legs syndrome symptoms compared with placebo. Efficacy outcomes for GEn at 600 mg were similar to placebo. Both GEn doses were generally well tolerated.