Restless legs syndrome outside the blood–brain barrier – Exacerbation by domperidone in Parkinson's disease

Restless Legs Syndrome, and symptoms of Restless Syndrome in patients with Graves' disease: a cross-sectional survey

OBJECTIVES

Restless legs syndrome (RLS) is a frequent comorbid condition associated with distinct unrelated diseases. While the incidence of RLS has not been definitively confirmed, RLS-like symptoms have been reported in a section of Asian population who also had hyperthyroidism. The prevalence of RLS is generally low in Asian populations. Under these circumstances, we hypothesized that in a population where RLS is common, such as in Brazil, RLS could manifest as a comorbid ailment alongside Graves' disease, a common hyperthyroid condition.

METHODS

In a cross-sectional survey, 108 patients who presented with Graves' disease were analyzed for restless legs or associated symptoms.

RESULTS

Twelve patients (11.1%) displayed symptoms of RLS prior to the incidence of Graves' disease. These patients experienced worsening of the symptoms during their hyperthyroid state. Six patients (5.6%) developed RLS, consequent upon the incidence of Graves' disease as per the consensus of the panel of the experts. Fifteen patients (13.9%) also presented with RLS-like symptoms without any discernible circadian feature of the syndrome.

CONCLUSION

Our findings confirm that Graves' disease might trigger restless legs-like symptoms, while the condition of hyperthyroidism could also be complicated by definite RLS.

A systematic review of the literature on disorders of sleep and wakefulness in Parkinson's disease from 2005 to 2015

Sleep disorders are among the most common non-motor manifestations in Parkinson's disease (PD) and have a significant negative impact on quality of life. While sleep disorders in PD share most characteristics with those that occur in the general population, there are several considerations specific to this patient population regarding diagnosis, management, and implications. The available research on these disorders is expanding rapidly, but many questions remain unanswered. We thus conducted a systematic review of the literature published from 2005 to 2015 on the following disorders of sleep and wakefulness in PD: REM sleep behavior disorder, insomnia, nocturia, restless legs syndrome and periodic limb movements, sleep disordered breathing, excessive daytime sleepiness, and circadian rhythm disorders. We discuss the epidemiology, etiology, clinical implications, associated features, evaluation measures, and management of these disorders. The influence on sleep of medications used in the treatment of motor and non-motor symptoms of PD is detailed. Additionally, we suggest areas in need of further research.

SLEEP AND CIRCADIAN RHYTHM DISORDERS IN PARKINSON'S DISEASE

Purpose of review

Sleep disorders are among the most challenging non-motor features of Parkinson's disease (PD) and significantly affect quality of life. Research in this field has gained recent interest among clinicians and scientists and is rapidly evolving. This review is dedicated to sleep and circadian dysfunction associated with PD.

Recent findings

Most primary sleep disorders may co-exist with PD; majority of these disorders have unique features when expressed in the PD population.

Summary

We discuss the specific considerations related to the common sleep problems in Parkinson's disease including insomnia, rapid eye movement sleep behavior disorder, restless legs syndrome, sleep disordered breathing, excessive daytime sleepiness and circadian rhythm disorders. Within each of these sleep disorders, we present updated definitions, epidemiology, etiology, diagnosis, clinical implications and management. Furthermore, areas of potential interest for further research are outlined.

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.

The clinical challenges of akathisia

Akathisia is one of the most vexing problems in neuropsychiatry. Although it is one of the most common side effects of antipsychotic medications, it is often difficult to describe by patients, and is difficult to diagnose and treat by practitioners. Akathisia is usually grouped with extrapyramidal movement disorders (ie, movement disorders that originate outside the pyramidal or corticospinal tracts and generally involve the basal ganglia). Yet, it can present as a purely subjective clinical complaint, without overt movement abnormalities. It has been subtyped into acute, subacute, chronic, tardive, withdrawal-related, and "pseudo" forms, although the distinction between many of these is unclear. It is therefore not surprising that akathisia is generally either underdiagnosed or misdiagnosed, which is a serious problem because it can lead to such adverse outcomes as poor adherence to medications, exacerbation of psychiatric symptoms, and, in some cases, aggression, violence, and suicide. In this article, we will attempt to address some of the confusion surrounding the condition, its relationship to other disorders, and differential diagnosis, as well as treatment alternatives.

Restless Legs Syndrome and Leg Motor Restlessness in Parkinson's Disease

Sleep disturbances are important nonmotor symptoms in Parkinson's disease (PD) that are associated with a negative impact on quality of life. Restless legs syndrome (RLS), which is characterized by an urge to move the legs accompanied by abnormal leg sensations, can coexist with PD, although the pathophysiology of these disorders appears to be different. RLS and PD both respond favorably to dopaminergic treatment, and several investigators have reported a significant relationship between RLS and PD. Sensory symptoms, pain, motor restlessness, akathisia, and the wearing-off phenomenon observed in PD should be differentiated from RLS. RLS in PD may be confounded by chronic dopaminergic treatment; thus, more studies are needed to investigate RLS in drug-naïve patients with PD. Recently, leg motor restlessness (LMR), which is characterized by an urge to move the legs that does not fulfill the diagnostic criteria for RLS, has been reported to be observed more frequently in de novo patients with PD than in age-matched healthy controls, suggesting that LMR may be a part of sensorimotor symptoms intrinsic to PD. In this paper, we provide an overview of RLS, LMR, and PD and of the relationships among these disorders.

Treatment of restless legs syndrome

OPINION STATEMENT

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