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

A survey-based approach on restless legs syndrome: practices and perspectives among Italian neurologists

INTRODUCTION

Restless Legs Syndrome (RLS) is a widely prevalent and complex neurological disorder. Despite notable advancements in managing RLS, the disorder continues to face challenges related to its recognition and management.

OBJECTIVE

This study seeks to gain comprehensive insights into the knowledge and clinical practices among Italian neurologists regarding RLS diagnosis, management, and treatment, comparing approaches among general neurologists, movement disorder specialists, and sleep experts.

METHODS

Members of the Italian Society of Neurology, the Italian Society of Parkinson and Movement Disorders, and the Italian Association of Sleep Medicine were invited to participate in a 19-question online survey.

RESULTS

Among the 343 surveyed neurologists, 60% categorized RLS as a "sleep-related movement disorder." Forty% indicated managing 5-15 RLS patients annually, with sleep specialists handling the highest patient volume. Of note, only 34% adhered strictly to all five essential diagnostic criteria. The majority (69%) favored low-dosage dopamine agonists as their first-line treatment, with movement disorder specialists predominantly endorsing this approach, while sleep experts preferred iron supplementation. Regular screening for iron levels was widespread (91%), with supplementation typically guided by serum iron alterations. In cases of ineffective initial treatments, escalating dopamine agonist dosage was the preferred strategy (40%).

CONCLUSIONS

These findings underscore a lack of a clear conceptualization of RLS, with a widespread misconception of the disorder as solely a movement disorder significantly influencing treatment approaches. Disparities in RLS understanding across neurology subspecialties underscore the necessity for improved diagnostic accuracy, targeted educational initiatives, and management guidelines to ensure consistent and effective RLS management.

Parent-Report Sleep Disturbances and Everyday Executive Functioning Difficulties in Children with Tourette Syndrome

There is an increasing need to identify and treat sleep disturbances in Tourette syndrome (TS), a neurodevelopmental condition characterized by tics. This study explored sleep, tics, and executive functioning in children with TS (n=136) and neurotypical controls (n=101) through parent-report scales and open-ended questions. 85% of children with TS scored in the clinical range for a sleep disorder. Higher tic severity predicted increased sleep disturbances and executive difficulties. Qualitative insights indicated a bidirectional link between sleep and tics, which warrants consideration in clinical settings. Further research is needed to explore causal links.

Sleep and Circadian Rhythm Disturbances in Diabetes: A Narrative Review

Sleep and circadian rhythm disturbances are less-known risk factors for the development and suboptimal outcomes of diabetes. The goal of this narrative review is to highlight the importance of sleep and circadian rhythm disturbances in the development and outcomes of type 1 diabetes (T1D) and type 2 diabetes (T2D), assess current treatment options and the possible mediating mechanisms. We performed a literature search using PubMed and selected relevant English and Dutch papers. Disturbances of sleep and circadian rhythm are common in people with diabetes. They are associated with an increased risk of developing T2D as well as with suboptimal diabetes outcomes (including higher HbA1c levels and reduced quality of life) for T1D and T2D. Preliminary data suggest that treatment of sleep and circadian rhythm disturbances could improve diabetes outcomes in people with T1D and T2D. Finally, the association with medical parameters appears to be mediated by disturbance in hormones, and by suboptimal self-care including forgetting or postponing glucose monitoring or medication use as well as higher consumption of high fat/high sugary foods. Diabetes may also disturb sleep, for example through nocturnal hypoglycemia and nocturia. We concluded that sleep and circadian rhythm disturbances are closely linked with diabetes. More attention to sleep in regular diabetes care is warranted, while further research is needed on treatment of sleep and circadian rhythm disturbances in the prevention of diabetes and its suboptimal outcomes.

Restless Legs Syndrome and the Use of Antipsychotic Medication: An Updated Literature Review

Restless legs syndrome or Willis-Ekbom disease (RLS/WED) is a sleep-related movement disorder characterized by an urge to move the legs. This impulse is usually accompanied by an uncomfortable and unpleasant sensation in the legs, which worsens at night and during periods of inactivity and is relieved by movement. Several studies in the literature reported the association between RLS and different antipsychotic medications. with Olanzapine, Quetiapine, and Clozapine identified as the most common causes. The literature suggests that the development of RLS in antipsychotic users may be attributed to the inhibition of dopaminergic neurotransmission or the impact of antipsychotics on iron metabolism. Diagnosing antipsychotic-induced RLS remains a substantial challenge in clinical practice, with challenges in the management of this condition also being widely reported in the current literature. In this article, we will review the evidence suggesting the association between RLS and the use of antipsychotic medications, differentiate between RLS and other movement disorders, and give a brief review of the pathophysiology, diagnosis, and management of RLS and its challenges among psychotic patients.

Sleep disorders in people with type 2 diabetes and associated health outcomes: a review of the literature

Sleep disorders are linked to development of type 2 diabetes and increase the risk of developing diabetes complications. Treating sleep disorders might therefore play an important role in the prevention of diabetes progression. However, the detection and treatment of sleep disorders are not part of standardised care for people with type 2 diabetes. To highlight the importance of sleep disorders in people with type 2 diabetes, we provide a review of the literature on the prevalence of sleep disorders in type 2 diabetes and the association between sleep disorders and health outcomes, such as glycaemic control, microvascular and macrovascular complications, depression, mortality and quality of life. Additionally, we examine the extent to which treating sleep disorders in people with type 2 diabetes improves these health outcomes. We performed a literature search in PubMed from inception until January 2021, using search terms for sleep disorders, type 2 diabetes, prevalence, treatment and health outcomes. Both observational and experimental studies were included in the review. We found that insomnia (39% [95% CI 34, 44]), obstructive sleep apnoea (55-86%) and restless legs syndrome (8-45%) were more prevalent in people with type 2 diabetes, compared with the general population. No studies reported prevalence rates for circadian rhythm sleep-wake disorders, central disorders of hypersomnolence or parasomnias. Additionally, several cross-sectional and prospective studies showed that sleep disorders negatively affect health outcomes in at least one diabetes domain, especially glycaemic control. For example, insomnia is associated with increased HbA_1c levels (2.51 mmol/mol [95% CI 1.1, 4.4]; 0.23% [95% CI 0.1, 0.4]). Finally, randomised controlled trials that investigate the effect of treating sleep disorders in people with type 2 diabetes are scarce, based on a small number of participants and sometimes inconclusive. Conventional therapies such as weight loss, sleep education and cognitive behavioural therapy seem to be effective in improving sleep and health outcomes in people with type 2 diabetes. We conclude that sleep disorders are highly prevalent in people with type 2 diabetes, negatively affecting health outcomes. Since treatment of the sleep disorder could prevent diabetes progression, efforts should be made to diagnose and treat sleep disorders in type 2 diabetes in order to ultimately improve health and therefore quality of life.

Functionally selective activation of the dopamine receptor D2 is mirrored by the protein expression profiles

The development of functionally selective or biased ligands is a promising approach towards drugs with less side effects. Biased ligands for G protein-coupled receptors can selectively induce G protein activation or β-arrestin recruitment. The consequences of this selective action on cellular functions, however, are not fully understood. Here, we investigated the impact of five biased and balanced dopamine D₂ receptor agonists and antagonists on the global protein expression in HEK293T cells by untargeted nanoscale liquid chromatography-tandem mass spectrometry. The proteome analysis detected 5290 protein groups. Hierarchical clustering and principal component analysis based on the expression levels of 1462 differential proteins led to a separation of antagonists and balanced agonist from the control treatment, while the biased ligands demonstrated larger similarities to the control. Functional analysis of affected proteins revealed that the antagonists haloperidol and sulpiride regulated exocytosis and peroxisome function. The balanced agonist quinpirole, but not the functionally selective agonists induced a downregulation of proteins involved in synaptic signaling. The β-arrestin-preferring agonist BM138, however, regulated several proteins related to neuron function and the dopamine receptor-mediated signaling pathway itself. The G protein-selective partial agonist MS308 influenced rather broad functional terms such as DNA processing and mitochondrial translation.

[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.