Differential Diagnoses of Restless Legs Syndrome/Willis-Ekbom Disease

Restless legs syndrome. Pathophysiology, diagnosis and treatment

Restless legs syndrome is the most prevalent sleep-related movement disorder, affecting 5-10% of the population, characterized by an urge to move that appears during rest or is exacerbated by rest, primarily in the lower extremities, that occurs in the evening or night and that disappears during movement or is improved by movement. Restless legs syndrome significantly impacts sleep, mood, and quality of life. Its pathophysiology involves a complex interplay of genetic and environmental factors, as well as comorbidities, leading to alterations in brain iron resulting in dysfunction in dopaminergic, adenosine, and glutamatergic pathways. Treatment typically includes iron supplementation and symptomatic therapy, traditionally utilizing dopamine agonists. However, their long-term use may exacerbate symptoms, relegating them to second-line treatment after ligands α2δ of calcium channels.

Restless legs syndrome variants: A systematic review

Introduction

Restless Legs Syndrome (RLS) is a clinical syndrome that may manifest itself in non-leg parts of the body as well, called RLS variant, which is considered a distinct entity by some researchers. In this systematic review, we tried to evaluate various clinical features and effective treatments of RLS variants and compare them with that of typical RLS.

Methods

This study was conducted following the PRISMA guideline. The primary search was performed in the data resources of Medline (PubMed), Web of Science, and Scopus, as well as the Google Scholar search engine. The required data were extracted from the studies.

Results

In this review, 1565 studies were initially identified and finally 39 studies were selected. The most common RLS variants were observed to involve hands, head, abdomen, and genitalia. These patients mostly complained of sleep disturbance and feelings of itching, tingling and twitching. Supportive diagnostic criteria of RLS including familial history of RLS, periodic limb movements during sleep (PLMS) and response to treatment with dopaminergic agents were assessed.

Conclusion

It seems that patients with RLS variant can undergo the same diagnostic and therapeutic work-up as patients with conventional RLS. It is suggested that these two disorders fall into the same syndromic spectrum.

Restless Legs Syndrome in Children and Adolescents

Children with psychiatric comorbidities frequently are referred for evaluation of sleep complaints. Common sleep symptoms can include difficulty falling asleep, frequent nocturnal awakening, restless sleep, and symptoms of restless legs syndrome (RLS). The understanding of the sleep condition in relation to the psychiatric comorbidity often is a challenge to the physician and often sleep disorders remain undiagnosed, untreated, or undertreated. Restless legs syndrome has been associated with psychiatric comorbidities and with certain medications, such as antidepressants, antihistamines, and antipsychotics. This article reviews the presentation of RLS and restless sleep, the association with psychiatric comorbidities, and treatment options.

Evaluation of the relationship between idiopathic restless legs syndrome and serum hepcidin levels

INTRODUCTION

The relationship between restless legs syndrome (RLS) and iron deficiency is a well-known topic. However, the etiology of the disease has not been determined. As the central iron deficiency is the most critical biological abnormality for RLS, we planned a study examining the relationship between RLS and hepcidin, which is the only regulatory hormone of iron metabolism known so far.

METHODS

International Restless Legs Syndrome Study Group diagnostic criteria (2014) were taken as a basis. A total of 40 RLS patients and 40 healthy controls were included in the study. To avoid the potential variables that might cause secondary RLS, all the participants were asked to provide hemogram, ferritin, iron, thyroid function tests, and sedimentation analysis. The hepcidin levels were measured with a Human Hepcidin (Hepc 25) ELISA kit (MyBioSource).

RESULTS

The statistically significant results of our analysis show that the red blood cell count, the neutrophil count, the percentage of lymphocytes and neutrophils, and, more distinctively, hepcidin levels were higher in RLS patients in comparison with the control group.

CONCLUSION

In this study, no differences were found in iron and ferritin values. High levels of hepcidin, the main regulator of iron metabolism, in those with primary RLS support the possibility that hepcidin may play a role in the pathogenesis of RLS. We think that larger studies on this subject can give clearer ideas.

Restless Legs Syndrome and Restless Sleep Disorder in Children

Restless legs syndrome (RLS) affects 2% of children presenting with symptoms of insomnia, restless sleep, decreased quality of life, and effects on cognition and behavior. The International RLS Study Group and the American Academy of Sleep Medicine have published guidelines for the diagnosis and treatment of RLS in children. Restless sleep disorder has been recently identified in children and presents with frequent movements during sleep and daytime symptoms with polysomnography findings of at least 5 large muscle movements at night. Treatment options for both disorders include iron supplementation, either oral or intravenous with improvement in nighttime and daytime symptoms.

Restless sleep disorder, restless legs syndrome, and periodic limb movement disorder-Sleep in motion!

Sleep-related movement disorders (SRMDs) represent an important part of pediatric sleep disorders. The most common complaint in SRMD is restless sleep at night. Restless sleep is reported in up to 80% of children with restless legs syndrome (RLS) and children with periodic limb movements of sleep (PLMS) disorder (PLMD). However, restless sleep causing daytime behavioral consequences can be seen in children without another apparent condition and has recently been identified as a new independent primary pediatric sleep disorder, called restless sleep disorder (RSD). This study describes these three main SRMDs (RSD, RLS, and PLMD), explains the new consensus criteria for RSD, emphasizes the rapidly evolving areas of research in this field, and proposes recommendations for future research. In particular, the published data constitute convincing evidence that sleep-related movements are disruptors of sleep quality and continuity. However, while important advancements have recently been reported in adults, a detailed analysis of the phenomenology and consequences of sleep-related movements has just started in children. New approaches, standardized diagnostic methods, and specific guidelines are needed in the field of pediatric SRMD.

Diagnostic and Treatment Considerations in Restless Legs Syndrome Complicated by Diabetic Neuropathy

PURPOSE OF REVIEW

Diabetic neuropathy from type I diabetes (DMI), type II diabetes (DMII), or gestational diabetes commonly occurs concurrently with restless legs syndrome (RLS) with an estimated prevalence in DMII specifically of 17.7 to 45%. The diagnosis of RLS can be obscured by symptoms of peripheral neuropathy, which may be similar to those of RLS, but also by other RLS mimics, including nocturnal leg cramps or akathisia. The purpose of this review is to outline a framework for considering comorbid diabetic neuropathy and RLS by discussing RLS and its association with peripheral nerve disease, diabetes, and sleep disruption. Treatment for patients with both diabetic neuropathy and RLS may differ from treatment of persons with solely RLS or diabetic neuropathy; key points in this difference are discussed. Finally, a treatment algorithm is provided to guide the approach to treating patients with comorbid RLS and diabetic neuropathy.

RECENT FINDINGS

There have been several revisions of the RLS diagnostic criteria which in addition to the main four essential criteria of having (1) an urge to move the legs which is (2) exacerbated by rest, (3) relieved temporarily by movement, and (4) occurs in the evening or night time, now includes a consideration for RLS mimics, requiring that (5) symptoms not be explained by any other symptoms. Additionally, the treatment of both diabetic neuropathy and RLS has evolved to focus first on controlling the blood glucose, avoiding exacerbating medications, supplementing with iron if serum ferritin is low, and starting pharmacotherapy with alpha-2-delta ligands such as gabapentin or pregabalin. Knowledge of the prevalence of peripheral neuropathy with RLS, revised RLS diagnostic criteria, and a general treatment algorithm for the combination of peripheral neuropathy and RLS is critical to providing appropriate care to patients suffering from these two diseases.

Restless Legs Syndrome in Children and Adolescents

Children with psychiatric comorbidities frequently are referred for evaluation of sleep complaints. Common sleep symptoms can include difficulty falling asleep, frequent nocturnal awakening, restless sleep, and symptoms of restless legs syndrome (RLS). The understanding of the sleep condition in relation to the psychiatric comorbidity often is a challenge to the physician and often sleep disorders remain undiagnosed, untreated, or undertreated. Restless legs syndrome has been associated with psychiatric comorbidities and with certain medications, such as antidepressants, antihistamines, and antipsychotics. This article reviews the presentation of RLS and restless sleep, the association with psychiatric comorbidities, and treatment options.

[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.

Emerging Concepts of the Pathophysiology and Adverse Outcomes of Restless Legs Syndrome

Restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED), is a common neurological disorder affecting up to 5% to 10% of the population, but it remains an underdiagnosed condition. RLS/WED is characterized by uncomfortable sensations, mainly in the legs, which appear during inactivity and worsen in the evening or at night. The prevalence of RLS/WED and periodic leg movements (PLMs) is increased in patients with sleep-disordered breathing, particularly in those with OSA, the most common sleep disorder encountered in sleep centers. New advances in the pathophysiology of RLS/WED have shown important implications for various genetic markers, neurotransmitter dysfunction, and iron deficiency. A practical approach to RLS/WED management includes an accurate diagnosis, the identification of reversible contributing factors, and the use of nonpharmacological therapies, including iron substitution (oral or IV) therapy. Many pharmacological agents are effective for the treatment of RLS/WED. Until recently, the first-line treatment of RLS/WED consisted of low-dose dopamine agonists (DA). However, given the fact that DAs cause high rates of augmentation of symptoms, international guidelines recommend that whenever possible the initial treatment of choice should be an α2δ ligand, and avoidance of dopaminergic agents unless absolutely necessary. If necessary, the lowest effective dose should be used for only the shortest possible time. The symptoms of RLS/WED can disrupt the quality of sleep as well as the quality of life. IV iron therapy may be considered in patients with refractory RLS. A better understanding of RLS/WED pathophysiology will allow patients to receive tailored therapy, resulting in an improved quality of life.

Creating cartoons to represent habitual leg movements

Many people have a habit of moving their legs and believe that this behavior is due to the restless legs syndrome (RLS), a highly prevalent neurological condition that greatly impairs the quality of life of affected individuals. This behavioral pattern, characterized by the habit of moving one's legs and feet, may be an important confounding factor in the diagnosis of RLS.

OBJECTIVE

To describe the main movements associated with this benign behavioral state to characterize a possible clinical condition that can contribute to the differential diagnosis of RLS.

METHODS

Experienced sleep specialists, who primarily see RLS patients listed the most frequent movements people without RLS report while describing their suspected RLS. We first compiled a list of the lower-limb movements described by the specialists. Then, one of the authors (KC) carried out all movements of the list on camera to obtain a video footage. This footage was sent to one of the authors, EPC, who, alongside a group of students, drew graphic representations (cartoons) of the recorded movements.

RESULTS

The panel of sleep experts described 13 leg movements commonly reported by their patients. The experts reported 11 simple movements and two combined movements.

CONCLUSION

In this study we developed an instrument that allows us to oppose and distinguish a pathological condition (RLS) from a behavioral phenomenon. This state of behavioral leg fidgeting needs to be better characterized and may eventually be recognized as a clinical entity per se.

Treatment of Comorbid Obstructive Sleep Apnea by Upper Airway Stimulation Results in Resolution of Debilitating Symptoms of Restless Legs Syndrome

ABSTRACT

An association between restless legs syndrome (RLS) and obstructive sleep apnea (OSA) has been suggested for decades but has been questioned in recent years given the apparently similar prevalence of RLS among patients with OSA and the general population. Still, marked improvement in symptoms of RLS has been reported in patients with OSA treated with continuous positive airway pressure (CPAP). Whether the effect of OSA treatment on RLS extends to modalities of OSA treatment other than CPAP remains an open question. Here, we report the case of a patient with OSA and comorbid debilitating RLS who underwent upper airway stimulation device implantation and subsequently experienced near-resolution of her severe RLS symptoms. Upper airway stimulation devices may be an option for patients with OSA and severe RLS intolerant to conventional CPAP modalities.

Differential Diagnosis and Treatment of Restless Legs Syndrome: A Literature Review

Restless legs syndrome (RLS) is a chronic neurological disorder affecting a growing number of people. Patients describe an irresistible urge to move their lower limbs in times of immobility. Due to its vague symptoms and similarity to other disorders, it has become increasingly difficult for primary care clinicians to properly diagnose and manage RLS. As a result, patients with RLS are routinely misdiagnosed and continue their lives without proper management. This literature review examines the current understanding of the disorder, provides key points to assist clinicians in differentiating RLS from similar disorders, and explores recently updated evidence-based guidelines for the effective management of RLS.

Plasma copeptin levels in patients with restless legs syndrome

OBJECTIVES

Copeptin, the C-terminal fragment of antidiuretic hormone, is a new biomarker that has been found to be elevated in several disorders and could be related with prognosis. This study aimed to compare plasma copeptin levels in patients with restless legs syndrome (RLS) with healthy individuals and to investigate whether plasma copeptin levels were associated with the severity of disease.

MATERIAL AND METHODS

41 patients with primary RLS, who were followed in Bakirkoy Psychiatry and Neurology Research and Training Hospital and 41 age- and sex-matched healthy individuals were included into the study. RLS patients were divided into subgroups as mild-moderate, severe, and very severe according to the severity of symptoms. Sleep quality and excessive daytime sleepiness were determined according to Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale, respectively, and sleep quality scores were analyzed statistically among the groups divided according to disease severity. Copeptin levels in all the patients were compared to the controls. RLS subgroups were compared with each other to evaluate association between copeptin levels and disease severity.

RESULTS

Plasma copeptin levels in RLS patients were significantly higher than controls (P < .001). However, there was no association between copeptin levels and disease severity. Excessive daytime sleepiness was found as 14.63% and low sleep quality as 68.29% in patients.

CONCLUSIONS

Hypothalamic-pituitary-adrenal axis activation and sympathetic hyperactivity in RLS might be responsible for increased Antidiuretic hormone (ADH) and copeptin release. We think that copeptin might have a potential role in the pathogenesis of RLS and be a biomarker for this disease.

Restless legs syndrome in Wilson's disease: frequency, characteristics, and mimics

OBJECTIVE

To determine characteristics, clinical significance, frequency, and mimics of restless legs syndrome (RLS) in a cohort of Wilson's disease (WD, n = 42/f = 18), compared to healthy, matched controls.

MATERIALS AND METHODS

Structured clinical interviews (patients and caregiving family members), repeated neurological examinations (afternoon and presleep), comprehensive laboratory tests, WD-, RLS-, and sleep-specific rating scales, and video-polysomnography.

RESULTS

Thirteen patients with WD (13/42 = 31.0%) clearly fulfilled the five diagnostic criteria of RLS; in eight patients (19.1%), the burden of RLS was clinically significant. The RLS was of moderate severity, equally distributed among sexes, manifested mainly in the evening and before falling asleep, and had developed mostly after clinical manifestation of WD (time elapsed 10.2 ± 14.5 years), still at a young mean age (27.5 ± 11.5 years). The known RLS-associated features were absent (normal iron and kidney parameters) or rare (positive family history, polyneuropathy). Compared to WD patients without RLS, patients with RLS were significantly elder and had suffered longer from WD. WD-specific RLS mimics as well as RLS confounding motor comorbidities (dystonia, tremor, chorea) were frequent and a diagnostic challenge; in difficult cases, the differentiation was reached by clinical observation of the motor behavior in the evening or at nighttime.

CONCLUSION

RLS was frequent in this cohort of WD and might be causally related to WD. RLS should be included in the diagnostic work-up of WD. In complex motor disorders, differential diagnosis of RLS might require evening/nighttime examination and video-polysomnography. In WD patients with a clinically significant RLS, treatment with dopaminergic substances may be considered.