The restless legs syndrome

Sleep-related and non-sleep-related migraine: interictal sleep quality, arousals and pain thresholds

Background

The mechanisms associating sleep and migraine are unknown. No previous polysomnographic (PSG) or pain-threshold (PT) study has compared patients with sleep-related migraine attacks (SM), non-sleep related migraine attacks (NSM) and healthy controls.

Methods

We have performed a blinded, prospective exploratory study with case–control design. Thirty-four healthy controls, 15 patients with SM and 18 patients with NSM had interictal PSG heat-, cold- and pressure PT (HPT, CPT, PPT) recordings and completed diary- and questionnaire on sleep and headache related aspects.

Results

NSM patients had more slow-wave sleep (SWS) and more K-bursts than SM patients (K-bursts: p = 0.023 and SWS: p = 0.030) and controls (K-bursts: p = 0.009 and SWS: 0.041). NSM patients also had lower HPT and CPT than controls (p = 0.026 and p = 0.021). In addition, SM patients had more awakenings and less D-bursts than controls (p = 0.025 and p = 0.041).

Conclusion

SM- and NSM patients differed in objective-, but not subjective sleep quality. NSM patients had PSG findings indicating foregoing sleep deprivation. As foregoing sleep times were normal, a relative sleep deficit might explain reduced PT among NSM patients. The SM patients had signs of slightly disturbed sleep.

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.

Comorbidities, medications and depressive symptoms in patients with restless legs syndrome and migraine

OBJECTIVE

The pathophysiology of migraine and restless legs syndrome (RLS) seems to involve inherited mechanism and dysfunction of the dopaminergic system. Previous articles have shown that the frequency of RLS is higher in migraine patients than in controls. We conducted a study to evaluate comorbidities, medication used and depressive symptoms that can explain the relation between migraine and RLS.

METHODS

A case-control study was performed in which patients with migraine (n=72) and a control group without migraine (n=72) were interviewed. Data including RLS diagnosis, depressive symptoms, comorbidities and drugs used were evaluated.

RESULTS

There was a significant association between migraine and RLS (p=0.01), but comorbidities such as diabetes, hypertension, anemia and drugs used did not explain this association. Depression scores, as measured by the Beck Depression Inventory, were higher in migraine patients with RLS (p =0.04).

CONCLUSION

No specific factors explaining the association between migraine and RLS were found. Symptoms of depression were more frequent in patients with migraine and RLS.

Drugs associated with restless legs syndrome: a case/noncase study in the French Pharmacovigilance Database

BACKGROUND

Several case reports have suggested that drugs could induce restless legs syndrome. However, no systematic review of this adverse drug reaction (ADR) in a pharmacovigilance database has been published.

OBJECTIVE

To assess the frequency of restless legs syndrome in the French Pharmacovigilance Database.

METHODS

We selected all ADR reports from January 1, 1984 to December 31, 2009 coded as restless legs syndrome. Restless legs syndrome diagnosis was validated from case descriptions. Using a case/noncase approach, reporting odds ratio and 95% confidence interval were calculated for "suspected'' drugs with 2 or more observations.

RESULTS

Twenty-six ADR reports were found. Four cases were excluded because of alternative diagnosis. Fourteen cases were women (64%). Median age was 57. Most frequently suspected drugs were antidepressants (reporting odds ratio, 15.9 [6.4-39.7]; amitriptyline, escitalopram, mianserine, mirtazapine, duloxetine), neuroleptics (17.8 [6.1-51.7]; thioridazine, loxapine, risperidone, aripiprazole) or tramadol (18.2 [6.3-52.8]).

CONCLUSIONS

Restless legs syndrome is a very rare ADR that was more frequently reported in association with antidepressants, neuroleptics, or tramadol.

Abnormal medial thalamic metabolism in patients with idiopathic restless legs syndrome

Pathophysiology of restless legs syndrome is poorly understood. A role of the thalamus, specifically of its medial portion which is a part of the limbic system, was suggested by functional magnetic resonance imaging and positron emission tomography studies. The aim of this study was to evaluate medial thalamus metabolism and structural integrity in patients with idiopathic restless legs syndrome using a multimodal magnetic resonance approach, including proton magnetic resonance spectroscopy, diffusion tensor imaging, voxel-based morphometry and volumetric and shape analysis. Twenty-three patients and 19 healthy controls were studied in a 1.5 T system. Single voxel proton magnetic resonance spectra were acquired in the medial region of the thalamus. In diffusion tensor examination, mean diffusivity and fractional anisotropy were determined at the level of medial thalamus using regions of interest delineated to outline the same parenchyma studied by spectroscopy. Voxel-based morphometry was performed focusing the analysis on the thalamus. Thalamic volumes were obtained using FMRIB's Integrated Registration and Segmentation Tool software, and shape analysis was performed using the FMRIB Software Library tools. Proton magnetic resonance spectroscopy study disclosed a significantly reduced N-acetylaspartate:creatine ratio and N-acetylaspartate concentrations in the medial thalamus of patients with restless legs syndrome compared with healthy controls (P < 0.01 for both variable). Lower N-acetylaspartate concentrations were significantly associated with a family history of restless legs syndrome (β = -0.49; P = 0.018). On the contrary, diffusion tensor imaging, voxel-based morphometry and volumetric and shape analysis of the thalami did not show differences between the two groups. Proton magnetic resonance spectroscopic findings in patients with restless legs syndrome indicate an involvement of medial thalamic nuclei of a functional nature; however, the other structural techniques of the same region did not show any changes. These findings support the hypothesis that dysfunction of the limbic system plays a role in the pathophysiology of idiopathic restless legs syndrome.

Pregnancy outcome following use of levodopa, pramipexole, ropinirole, and rotigotine for restless legs syndrome during pregnancy: a case series

BACKGROUND

Restless legs syndrome (RLS) is related to parity, and its symptoms may worsen during pregnancy. Treatment with levodopa or dopamine agonists is the first-line therapy for RLS; however, there are limited data on treatment in pregnancy. We therefore assessed the safety of levodopa, pramipexole, rotigotine, and ropinirole in pregnancy.

METHODS

Prospective documentation of pregnancies exposed to levodopa, pramipexole, rotigotine, and ropinirole between 1998 and 2011 was evaluated as to their outcome (teratogenicity or fetotoxicity) by the Berlin Institute for Clinical Teratology and Drug Risk Assessment in Pregnancy.

RESULTS

We were able to complete 59 pregnancy outcomes exposed to RLS pharmacotherapy. For specific treatments, the numbers of exposed pregnancies/live born children/spontaneous abortions/induced abortions/malformations were as follows: levodopa only: 38/29 (one pair of twins)/3/7/3; pramipexole only: 12/9/3/0/0; rotigotine only: 2/2/0/0/0; ropinirole only: 3/2/0/1/0; levodopa combined with pramipexole: 3/3/0/0/0; levodopa combined with ropinirole: 1/1/0/0/0. No major birth defects were found with any RLS treatment, and three infants exposed to levodopa had minor anomalies.

CONCLUSIONS

In our small prospective case series, there was no increased risk above baseline for major malformations or other adverse outcomes for levodopa and pramipexole. If necessary, levodopa treatment may be considered as an alternative to cabergoline, for which safety has been well documented in pregnancy.

Sleep disorders in Parkinson's disease

Sleep disorders in Parkinson's disease (PD) are frequent and have numerous etiologies. Both nighttime sleep disturbances and daytime sleepiness can occur. The key to effective treatment is appropriate diagnosis. A careful interview of the patient and his or her bed partner provides direction for additional evaluations. Referral to a sleep specialist for quantitative studies is necessary to evaluate for rapid eye movement (REM) sleep behavior disorder, sleep apnea, periodic limb movements, and other sleep disorders. Excessive daytime sleepiness may be attributed to interrupted nighttime sleep or daytime medications (particularly the dopamine agonists) or it may be intrinsic to PD. When the diagnosis is established, treatment is directed toward the primary sleep disturbance. Fragmented sleep due to recurrence of PD symptoms may improve with the use of long-acting preparations of carbidopa/levodopa. Sleep apnea is treated using continuous positive airway pressure, and REM sleep behavior disorder may improve using pharmacologic interventions, although controlled trials are lacking. Restless legs syndrome and periodic limb movements during sleep are treated with direct dopaminergic agonists at bedtime. Excessive daytime sleepiness related to the use of direct dopaminergic agonists may improve with dosage reduction or discontinuation. Stimulants such as modafinil may provide modest benefit.

The burden of restless legs syndrome: an assessment of work productivity, sleep, psychological distress, and health status among diagnosed and undiagnosed individuals in an internet-based panel

BACKGROUND

Restless legs syndrome (RLS) affects approximately 10-15% of the general population and has deleterious effects on sleep and subsequent daytime performance. The disorder may also give rise to long-term complications such as psychological distress and diminished quality of life. The condition is often unrecognized or misdiagnosed, and the magnitude of the effects of RLS on the sizeable proportion of undiagnosed (and therefore untreated) individuals has not previously been evaluated.

OBJECTIVES

This study examined the impact of RLS on overall health status, sleep, psychological functioning, work productivity, and daily activities in individuals with diagnosed and in those with undiagnosed (self-reported) RLS.

METHODS

An internet-based survey was conducted on a multimillion-member panel of US adults. Eligible participants were currently experiencing RLS symptoms as determined using established diagnostic criteria. Participants provided information related to self-reported RLS diagnosis, treatment, symptom frequency and severity, and responses to validated instruments (Medical Outcomes study [MOS] Short Form 12, version 2 [SF-12v2], MOS Sleep Scale, Center for Epidemiological Studies Depression Scale [CES-D], Work Productivity and Activity Impairment - General Health Questionnaire [WPAI-GH] and Work Limitations Questionnaire [WLQ]). Analysis of co-variance (ANCOVA) models were developed to evaluate the relationships among symptom severity, diagnosis status, age, and sex, and the impact of RLS.

RESULTS

Participants included 702 adults with RLS symptoms. Means for the SF-12v2 scores (physical component score = 35.6, mental component score = 42.6) were at least 1 standard deviation lower than sex- and age-adjusted general population norms. Participants reported poorer sleep quality scores across each MOS Sleep Scale domain, with differences from published norms of >16 points on 100-point scales, as well as approximately 1 hour less sleep per night on average. A majority (64%) met the cut-off score for depression. Compared with population norms, the sample reported greater limitations in time management, physical demands, mental/interpersonal demands, general work output, and usual activities. Symptom intensity and frequency were shown to be the primary predictors of RLS impact on the various outcomes.

CONCLUSION

These results support previous reports that RLS often goes undiagnosed or misdiagnosed. The results of this survey also suggest that regardless of whether RLS is recognized, the burden of the disorder is substantial, implying a need for improved diagnosis and management of RLS.

ADMET considerations for restless leg syndrome drug treatments

INTRODUCTION

Restless legs syndrome (RLS) is a common neurological disorder that might impair nocturnal rest causing decreased alertness, depressed mood, reduced job performance, and poor quality of life. In patients affected by severe RLS, a pharmacological treatment is mandatory.

AREAS COVERED

The present review is based on a search using PubMed from 1994 to 2012. It is focused on the Absorption, Distribution, Metabolism, Elimination and Toxicology (ADMET) characteristics of the most used medications for RLS. In particular, the ADMET characteristics of dopaminergic agents, anticonvulsants able to improve neuropathic pain, and iron were discussed.

EXPERT OPINION

Clinical trials have showed that non-ergolic dopamine agonists are efficacious and safe for patients affected by moderate to severe idiopathic RLS. However, no head-to-head study has compared the long-term effects of the three dopamine agonists approved by the FDA for RLS (ropinirole, pramipexole, and rotigotine). Moreover, further studies should investigate the extended-release formulation of ropinirole and pramipexole in RLS patients affected by all day long distressing symptoms. A standardized treatment for symptomatic forms of RLS is lacking. Randomized, placebo-controlled trials should be performed at least in RLS patients with peripheral neuropathic and chronic kidney disease. Concerning RLS due to iron deficiency, a head-to-head study comparing efficacy, safety and compliance of oral iron versus intravenous one seems to be needed.

Clinical correlates of the restless legs syndrome

OBJECTIVE: To determine the clinical correlates of the restless legs syndrome (RLS) in a Brazilian sleep disorders center. METHODS: We retrospectively studied 118 patients with RLS from January, 2004, to December, 2010. The analyzed variables were: age at disease onset, gender, race, years of school instruction, primary and secondary RLS, and treatment options. RESULTS: Among the studied patients, 83.9% were women with a female/male sex ratio of 5:1. Mean age of the patients at symptom onset ± standard deviation was 41.7±17.9 years-old. The primary RLS was found in 85% of patients. The other 15% remainders consisted of secondary forms, and they were associated with neuropathy, iron deficiency anemia, end-stage renal disease, or Parkinson's disease. Drug therapy for RLS was introduced in 67% of patients. CONCLUSIONS: Most patients presented primary RLS with an early disease onset. Further epidemiological studies are welcomed to provide better information on secondary RLS in Brazil.

Motor restlessness, sleep disturbances, thermal sensory alterations and elevated serum iron levels in Btbd9 mutant mice

Restless legs syndrome (RLS), also known as Willis-Ekbom disease, is a sensory-motor neurological disorder with a circadian component. RLS is characterized by uncomfortable sensations in the extremities, generally at night or during sleep, which often leads to an uncontrollable urge to move them for relief. Recently, genomic studies identified single-nucleotide polymorphisms in BTBD9, along with three other genes, as being associated with a higher risk of RLS. Little is known about the function of BTBD9 or its potential role in the pathophysiology of RLS. We therefore examined a line of Btbd9 mutant mice we recently generated for phenotypes similar to symptoms found in RLS patients. We observed that the Btbd9 mutant mice had motor restlessness, sensory alterations likely limited to the rest phase, and decreased sleep and increased wake times during the rest phase. Additionally, the Btbd9 mutant mice had altered serum iron levels and monoamine neurotransmitter systems. Furthermore, the sensory alterations in the Btbd9 mutant mice were relieved using ropinirole, a dopaminergic agonist widely used for RLS treatment. These results, taken together, suggest that the Btbd9 mutant mice model several characteristics similar to RLS and would therefore be the first genotypic mouse model of RLS. Furthermore, our data provide further evidence that BTBD9 is involved in RLS, and future studies of the Btbd9 mutant mice will help shine light on its role in the pathophysiology of RLS. Finally, our data argue for the utility of Btbd9 mutant mice to discover and screen novel therapeutics for RLS.

Increased risks of parkinsonism in the 3 years after chronic renal failure

AIMS

Movement disorders are one of the central nervous system complications in uremic patients. Asterixis, multifocal myoclonus, and restless leg syndrome are well-documented in this category. Acute parkinsonism, however, is only reported in rare series with a small number of cases. In this study, we investigated the risk for parkinsonism during a 3-year follow-up period after a diagnosis of uremia.

METHODS

The Longitudinal Health Insurance Database in Taiwan was utilised. We identified a total of 2862 patients who had visited ambulatory care centers with a diagnosis of chronic renal failure between 1999 and 2001 as the study cohort. We further randomly selected 14,310 enrollees matched with the study cohort in terms of gender, age, and year of their index visit for comparison. Each patient was individually tracked for 3 years to identify the occurrence of parkinsonism. Stratified Cox proportional hazard regressions (stratified by age and gender) were performed for analyses.

RESULTS

We found the annual incidence rates of parkinsonism to be 1.2% and 0.6% in the uremic and non-uremic groups, respectively. Furthermore, uremic patients were more vulnerable to developing parkinsonism with a 1.81-fold higher risk [95%CI = (1.21-2.71)] than the non-uremic group after adjusting for diabetes mellitus, which did not augment the risk.

CONCLUSIONS

The importance of raising awareness regarding the early symptoms of parkinsonism among patients with uremia is tied to its early identification, with timely aggressive dialysis being able to apply to slow the progression of the disease and its symptoms. Further study is warranted to elucidate the pathophysiology of uremic parkinsonism.

Restless legs syndrome during and after pregnancy and its relation to snoring

OBJECTIVE

To study development of restless legs syndrome (RLS) during and after pregnancy, and whether RLS is related to snoring or other pregnancy-related symptoms.

DESIGN

Prospective study.

SETTING

Antenatal care clinics in the catchment area of Linköping university hospital, Sweden.

POPULATION

Five hundred consecutively recruited pregnant women.

METHODS

Sleep disturbances, including symptoms of RLS and snoring, were assessed with questionnaires in each trimester. A complementary questionnaire was sent three years after delivery to women experiencing symptoms of RLS during pregnancy.

MAIN OUTCOME MEASURES

Symptoms of RLS in relation to snoring in each trimester.

RESULTS

Symptoms of RLS were reported by 17.0% of the women in the first trimester, by 27.1% in the second trimester and by 29.6% in the third trimester. Snoring in the first trimester was correlated to increased prevalence of RLS in all three trimesters (p= 0.003, 0.017 and 0.044 in the first, second and third trimester, respectively). No correlation was found between RLS and anemia, parity or body mass index. Among the women who experienced RLS, 31% still had symptoms three years after delivery. Fifty-eight per cent of those whose symptoms had disappeared stated that this happened within one month after delivery.

CONCLUSIONS

Symptoms of RLS progressed most between the first and second trimester. Women who snored in the first or second trimester of pregnancy had a higher prevalence of RLS in the third trimester, which indicates that snoring in early pregnancy might predict RLS later. Symptoms of RLS disappear quite soon after delivery, but about one-third of women with RLS during pregnancy may still have symptoms three years after childbirth.

Frequency of impulse control behaviours associated with dopaminergic therapy in restless legs syndrome

Background

Low doses of dopamine agonists (DA) and levodopa are effective in the treatment of restless legs syndrome (RLS). A range of impulse control and compulsive behaviours (ICBs) have been reported following the use of DAs and levodopa in patients with Parkinson's disease. With this study we sought to assess the cross-sectional prevalence of impulse control behaviours (ICBs) in restless legs syndrome (RLS) and to determine factors associated with ICBs in a population cohort in Germany.

Methods

Several questionnaires based on validated and previously used instruments for assessment of ICBs were mailed out to patients being treated for RLS. Final diagnoses of ICBs were based on stringent diagnostic criteria after psychiatric interviews were performed.

Results

10/140 RLS patients of a clinical cohort (7.1%) were finally diagnosed with ICBs, 8 of 10 on dopamine agonist (DA) therapy, 2 of 10 on levodopa. 8 of the 10 affected patients showed more than one type of abnormal behaviour. Among those who responded to the questionnaires 6/140 [4.3%] revealed binge eating, 5/140 [3.6%] compulsive shopping, 3/140 [2.1%] pathological gambling, 3/140 [2.1%] punding, and 2/140 [1.4%] hypersexuality in psychiatric assessments. Among those who did not respond to questionnaires, 32 were randomly selected and interviewed: only 1 patient showed positive criteria of ICBs with compulsive shopping and binge eating. ICBs were associated with higher DA dose (p = 0.001), younger RLS onset (p = 0.04), history of experimental drug use (p = 0.002), female gender (p = 0.04) and a family history of gambling disorders (p = 0.02), which accounted for 52% of the risk variance.

Conclusion

RLS patients treated with dopaminergic agents and dopamine agonists in particular, should be forewarned of potential side effects. A careful history of risk factors should be taken.

Drug-induced sleep: theoretical and practical considerations

Faithful replication of normal sleep through medications--can it be achieved? Departure from normal sleep with the use of drugs--when is it desired? Answers to these questions depend on accurate understanding of sleep and on concrete criteria upon which to define it. Since these elements are evolving sciences, as yet incompletely known, one might take a nihilistic approach that we simply cannot judge whether we have successfully replicated sleep, since we do not fully grasp what sleep is or what it does. To address these potential obstacles, our article is written in two sections. The first addresses theoretical considerations for how medications might be seen in the larger framework of sleep. The purpose of this section is to inform readers about key issues in evaluating whether a drug has sufficient data to persuasively argue it is re-creating sleep. (We hope that researchers interested in conducting studies, or critical readers of the drug-study literature, might find this section particularly useful.) The second section of this article approaches exemplary, current concepts of pharmacologic manipulation of sleep, organized by disorders as articulated by the International Classification of Sleep Disorders (2005). This second section will combine practical knowledge of clinical sleep medicine, with emphasis on contemporary knowledge about molecular mechanisms that are felt to underlie some of these phenomena. We recognize that our collective knowledge about sleep will advance in the coming years. We hope that this article serves to facilitate that advance.

The use of rotigotine in the treatment of restless legs syndrome

Restless legs syndrome (RLS) is a neurological disorder characterized by an urge to move the legs often accompanied by unpleasant sensations. Symptoms appear during periods of rest or inactivity, particularly in the evening and at night, and are usually relieved by movement. The prevalence of RLS among Whites is approximately 5-15%. RLS can be distinguished into primary and secondary forms. Most patients (70-80%) are affected by the primary form of RLS. The uncomfortable sensations related to RLS often cause a minimal discomfort, thus a therapeutic approach is not necessary. However, almost 3% of the general population reports to be affected by severe symptoms of RLS, requiring pharmacological treatment. Secondary forms of RLS are relieved by the remission of the underlying clinical condition. Dopamine agonists are considered to be first-line treatments for primary RLS. Rotigotine is a nonergoline dopamine agonist with selectivity for D1, D2 and D3 receptors. It is administered once a day in the form of an adhesive matrix patch. The efficacy and safety of the drug in patients with primary RLS has been demonstrated by four clinical trials using dosages of 0.5, 1, 2, 3 and 4 mg/24 h. A dose-response relationship was observed between the dosages of 0.5 and 3 mg/24 h. Side effects were usually mild, the most frequent being skin reaction at the site of patch application. More trials are ongoing and results will soon be published for the long-term (5 years) treatment of RLS with rotigotine transdermal patches. Rotigotine is a promising drug for the treatment of RLS. Its continuous delivery throughout 24 h makes it especially indicated for those cases also presenting daytime symptoms, and for those presenting the so-called augmentation syndrome after prolonged treatment with L-dopa or dopamine agonists.

Restless Legs Syndrome in Behçet's Disease

The prevalence of restless legs syndrome (RLS) and its association with the clinical features of Behçet's disease (BD) has not previously been elucidated. The inflammatory character, central nervous system involvement and neuropathies of BD led to this investigation of RLS risk in BD patients. A total of 116 BD patients and 104 healthy control subjects were included; seven BD patients were excluded because of concurrent diseases, pregnancy or alcohol misuse that might cause RLS symptoms, and the remaining 109 BD patients were included in the analysis. The prevalence of RLS was significantly higher in patients with BD (32/109; 29.4%) than in controls (5/104; 4.8%). No significant differences were found between BD patients with and without RLS with regard to the clinical features of BD. RLS severity positively correlated with age in BD patients. In conclusion, BD-related RLS should be considered in symptomatic RLS secondary to rheumatological disorders and BD patients should be examined for RLS. Further studies are needed to clarify the pathogenetic mechanisms underlying BD-related RLS.

Opioid-mediated regulation of A11 diencephalospinal dopamine neurons: pharmacological evidence of activation by morphine

Dopamine (DA) neurons of the A11 diencephalospinal system represent the sole source of DA innervation to the spinal cord in mice, serving neuromodulatory roles in the processing of nociceptive input and movement. These neurons originate in the dorso-caudal diencephalon and project axons unilaterally throughout the rostrocaudal extent of the spinal cord, terminating predominantly in the dorsal horn. The density of A11 DA axon terminals in the lumbar region is greater in males compared to females, while in both sexes the activity of neurons terminating in the thoracic spinal cord is greater than those terminating in the lumbar region. The present study was designed to test the hypothesis that A11 DA neurons are activated by opioids. To test this hypothesis, male and female mice were systemically treated with agonists or antagonists acting at the μ-opioid receptor, and spinal cord concentrations of DA and its metabolite DOPAC were determined in the thoracic and lumbar spinal cord using high performance liquid chromatography coupled with electrochemical detection. Systemic administration of the μ-opioid agonist morphine led to a dose- and time-dependent increase in spinal cord DOPAC/DA ratio (an estimate of DA neuronal activity) in both male and female mice, with greater changes occurring in the lumbar segment. Blockade of opioid receptors with the opioid antagonist naloxone reversed the stimulatory effects of morphine on A11 DA neurons in both male and female mice, but had little to no effect on the activity of these neurons when administered alone. Present findings are consistent with the conclusion that spinal cord-projecting axon terminals of A11 DA neurons are activated by opioids in both male and female mice, most likely through a dis-inhibitory mechanism.

Depression in patients with rheumatoid arthritis: description, causes and mechanisms

Two sets of contributory factors to depression among patients with rheumatoid arthritis (RA) are generally examined - the social context of the individual and the biologic disease state of that person's RA. This article will review the evidence for both. RA affects patients both physically and psychologically. Comorbid depression is common with RA and leads to worse health outcomes. Low socioeconomic status, gender, age, race/ethnicity, functional limitation, pain and poor clinical status have all been linked to depression among persons with RA. Systemic inflammation may also be associated with, cause, or contribute to depression in RA. Understanding the socioeconomic factors, individual patient characteristics and biologic causes of depression in RA can lead to a more comprehensive paradigm for targeting interventions to eliminate depression in RA.

Health-related quality of life and restless legs syndrome among women in Sweden

AIM

Restless legs syndrome (RLS) is a common neurological movement disorder with a female preponderance, an increasing prevalence with age and comorbidity. Previous studies on the relationship between health-related quality of life (HRQOL) and RLS are still sparse but knowledge is increasing. The aim of this study was to evaluate the unique impact of RLS on HRQOL in a population-based sample.

METHODS

A random sample of 5000 women aged 25-64 years was selected from the general Swedish population. The women were sent diagnostic questions on RLS together with the Short Form 12 (SF-12) questionnaire for assessment of physical and mental HRQOL. The unique burden of RLS on HRQOL was analyzed by excluding RLS-positive women from four self-reported diagnostic groups (diabetes, depression, heart problems, muscle and joint pain) and by excluding subjects with these diagnoses from the group of RLS-positive women.

RESULTS

Compared with mental SF-12 scores for the RLS-negative women in our population, mental HRQOL of the RLS sample in our study was lower in every age group but not significantly lower in the age group 35-44 years. Physical SF-12 scores for RLS-positive women were also below scores for RLS-negative women in every age group but significance was only found in women between 45 and 54 years. A unique burden of RLS on HRQOL remained after statistical adjustment for comorbidities.

CONCLUSION

RLS-positive women had an impaired mental HRQOL compared to RLS-negative women in the studied population. The physical aspects of HRQOL were less affected among RLS-positive women. The impaired well-being among women with RLS further strengthens the importance of identifying women with this condition and evaluating their need for medication or other actions in order to improve their quality of life.

Treatment of moderate to severe restless legs syndrome: 2-year safety and efficacy of rotigotine transdermal patch

BACKGROUND

Rotigotine is a unique dopamine agonist with activity across D1 through D5 receptors as well as select adrenergic and serotonergic sites. This study reports the 2-year follow-up safety and efficacy data of an ongoing open-label multicenter extension study (NCT00498186) of transdermal rotigotine in patients with moderate to severe restless legs syndrome (RLS).

METHODS

Patients received a once-daily patch application of an individually optimized dose of rotigotine between 0.5 mg/24 h to 4 mg/24 h. Safety assessments included adverse events (AEs) and efficacy was measured by the International RLS Study Group Severity Rating Scale (IRLS), RLS-6 scales and Clinical Global Impression (CGI). Quality of life (QoL) was measured by QoL-RLS.

RESULTS

Of 310 patients who completed a 6-week placebo-controlled trial (SP709), 295 (mean age 58 ± 10 years, 66% females) were included in the open-label trial SP710. 64.7% (190/295 patients) completed the 2-year follow-up; 29 patients discontinued during the second year. Mean daily rotigotine dose after 2 years was 2.93 ± 1.14 mg/24 h with a 2.9% dose increase from year 1. Rotigotine was generally well tolerated. The rate of typical dopaminergic side effects, nausea and fatigue, was low (0.9% and 2.3%, respectively) during the second year; application site reactions were frequent but lower than in year 1 (16.4% vs. 34.5%). The IRLS total score improved from baseline of SP709 (27.8 ± 5.9) by 17.2 ± 9.2 in year 2 completers. Similar improvements were observed in RLS-6 scales, CGI scores and QoL-RLS. The responder rate in the CGI change item 2 ("much" and "very much" improved) was 95% after year 2.

CONCLUSIONS

Transdermal rotigotine is an efficacious and well-tolerated long-term treatment option for patients with moderate to severe RLS with a high retention rate during 2 years of therapy.

TRIAL REGISTRATION

NCT00498186.

Restless legs syndrome in a population of northern Tanzania: a community-based study

Restless legs syndrome (RLS) is a highly prevalent movement disorder. However, prevalences seem to vary amongst different ethnicities. To date, no community-based prevalence studies on RLS have been reported from the African continent. We have conducted a community-based, door-to-door study in northern Tanzania. Over a period of 16 months, 7,654 people aged 14 years and older were screened for the RLS Essential Diagnostic Criteria. Sampling was performed according to the method of "multistage cluster sampling." People who screened positive where reinterviewed and physically examined by a specialist neurologist. During the screening phase, 10 people answered "yes" to at least one of the screening questions. After reinterviewing those people, the result was confirmed in five people only. After careful re-evaluation of the results, only one person was diagnosed with RLS. Because of methodological limitations a definite prevalence may only be calculated from larger population-based studies of different African ethnicities with screening questions adapted to the cultural context.

Randomized trials of dopamine agonists in restless legs syndrome: a systematic review, quality assessment, and meta-analysis

BACKGROUND

The use of dopamine agonists (DAs) for the treatment of restless legs syndrome (RLS) has been assessed in numerous randomized clinical trials (RCTs).

OBJECTIVES

The aims of this study were to assess the reporting quality of published RCTs according to the Consolidated Standards of Reporting Trials (CONSORT) statement and to synthesize the study results in terms of efficacy and tolerability to inform the clinical management of RLS.

METHODS

PubMed and Cochrane Controlled Trials Register were searched for English-language RCTs that assessed the effects of DAs in RLS. Quality of reporting was measured using the proportion of 17 CONSORT checklist items included in each study. The 2 primary outcomes were pooled mean change from baseline in International RLS (IRLS) Study Group rating scale score (Deltamu) (95% CI) and relative risk (RR) (95% CI) of response based on the Clinical Global Impression-Improvement (CGI-I) scale score. The pooled proportions of adverse events (PAEs) (95% CI) were also estimated.

RESULTS

Eighteen RCTs (N = 2848 patients) were included. Two of the 17 CONSORT checklist items were reported in 7 studies (39%) and 9 of the 17 items were reported in all 18 studies (100%). The differences in the IRLS scores and RR for CGI-I were significantly greater with pramipexole, ropinirole, rotigotine, and cabergoline compared with placebo. Results for heterogeneity were nonsignificant. The difference in Deltamu (95% CI) was significant with pramipexole (-6.63 [-9.15 to -4.10]) versus ropinirole (-3.64 [-4.76 to 2.51]) (P = 0.04). The difference between pramipexole and rotigotine was nonsignificant. The pooled PAEs (95% CI) for pramipexole, ropinirole, and rotigotine were 4.8% (2.0% to 8.7%), 10.2% (2.6% to 22.1%), and 7.6% (1.3% to 18.5%), respectively. In the trial of sumanirole, the PAE value was 2% (0% to 5.4%).

CONCLUSION

Based on the findings from the meta-analysis, DAs were significantly more efficacious in the treatment of RLS compared with placebo.

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.

Depressive disorders in restless legs syndrome: epidemiology, pathophysiology and management

Epidemiological studies report a 2- to 4-fold risk of a depressive disorder in patients with restless legs syndrome (RLS) compared with healthy controls. The high prevalence rates of depression in RLS indicate an association between the two disorders. Severe sleep disturbance due to the nightly occurrence of RLS symptoms is a common complaint of patients with moderate or severe RLS and may substantially contribute to the emergence of depressive symptoms. Difficulty in the diagnosis of a depressive disorder in patients with RLS may arise from the overlap of symptoms in the two disorders, as sleep-related complaints are frequent both in RLS and depression. The treatment of depression in RLS has some unique aspects, as several antidepressants have been reported to trigger or worsen RLS. To date, no studies have been published regarding the course of depression in untreated and treated patients with RLS. On the other hand, the presence of co-morbid depression can have a substantial impact on the global treatment outcome. In patients with co-morbid moderate/severe depression, antidepressant therapy in parallel with or shortly after commencing RLS treatment is usually necessary. Data from recent trials with dopamine receptor agonists indicate that mild to moderate depressive symptoms are often relieved with improvement of RLS symptoms.

Compulsive habits in restless legs syndrome patients under dopaminergic treatment

Since the introduction of levodopa therapy and dopaminergic replacement therapy to abate symptoms of idiopathic Parkinson's disease, repetitive compulsive behaviors have been reported and are now considered to be drug-related response complications. As dopamine (DA) agonists are the licensed treatment in Restless Legs Syndrome (RLS), a survey was conducted to determine the extent to which patients with RLS present compulsive behaviors. The aim of this study was to investigate the relationship between DA agonists and the occurrence of motor or behavioral compulsions, stress, depression, and sleep disturbance in RLS patients. A questionnaire was mailed three times, at four-month intervals over a period of 8 months to all patients of the Quebec Memory and Motor Skills Disorders Clinic diagnosed with RLS. In addition to recording all medication information for RLS treatment, patients were assessed on the International Restless Legs Syndrome Study Group Rating Scale (IRLS), the Beck Depression Inventory-II (BDI-II), the Sleep Scale from the Medical Outcomes Study (MOS) and on a visual analog scale for current level of stress. A section pertaining to hobby, mania, and compulsion was also included. Analyses are based on 97 out of 151 patients (64.2%) with RLS who returned the three questionnaires. Twelve patients (12.4%) on stable DA agonist therapy (average dose 0.52+/-0.59 mg Pramipexole equivalent) developed a new compulsive behavioral repertoire. Eating (3 women, 1 man), buying food or clothes (2 women, 1 man), trichotillomania (1 woman, 1 man), and gambling (1man) were among the compulsions developed under DA treatment. In addition, two women presented new tic-like phenomena. In contrast to the RLS patients without compulsive behaviors (53 treated with DA agonist; 32 untreated), those with compulsive habits reported experiencing more stress, depression and sleep problems. Patients with RLS with mood and stress states may be at greater risk of developing compulsive behaviors while receiving standard dosage DA agonist treatment. These behaviors are clearly linked to short-term satisfaction and underline the role of dopaminergic mesolimbic stimulation in the reinforcement process of rewarding behavioral sequences.

Risk of preterm delivery and other adverse perinatal outcomes in relation to maternal use of psychotropic medications during pregnancy

OBJECTIVE

The purpose of this study was to determine the association of maternal psychotropic medication use during pregnancy with preterm delivery and other adverse perinatal outcomes.

STUDY DESIGN

A cohort of 2793 pregnant women in Washington State was interviewed, and their medical files were abstracted. Logistic regression models were constructed to assess odds ratios for perinatal outcomes by use of psychotropic medications.

RESULTS

Maternal use of benzodiazepine during pregnancy was associated with an increased risk of preterm delivery (adjusted odds ratio, 6.79; 95% confidence interval, 4.01-11.5) and with increased risks of low birthweight, low Apgar score, neonatal intensive care unit admissions, and respiratory distress syndrome. Selective serotonin receptor inhibitors were associated with preterm deliveries only among women who started treatment after the first trimester.

CONCLUSION

Benzodiazepine was associated highly with preterm delivery and other adverse perinatal outcomes. Well-conducted cohort studies are warranted to draw conclusions about risks and benefits of psychotropic medication use during pregnancy.

Restless legs syndrome

Restless legs syndrome (RLS) is a common neurological sensory-motor disorder that is characterized by intense restlessness and unpleasant creeping sensations deep inside the lower legs. Symptoms appear when the legs are at rest and are worst in the evening and at night. They force patients to keep moving their legs, and often to get out of bed and wander about. Periodic limb movements (PLMS) are also common during sleep amongst those suffering from RLS, and sleep efficiency is severely reduced. There are idiopathic as well as symptomatic forms of RLS, the latter being associated with e.g. pregnancy, iron deficiency and chronic renal failure. A family history of RLS is very common and pedigrees in these cases suggest an autosomal-dominant transmission with high penetrance. Genetic investigations have been performed in order to identify genes associated with RLS. Several loci have been found (on chromosomes 12q, 14q, 9p, 2q, 20p and 16p). Pathophysiology of RLS remains incompletely understood. However, advanced brain imaging studies and positive results of dopaminergic treatment suggest that RLS may be generated by dopamine dysfunction locally within the central nervous system. At present, there is a wide range of treatment options including levodopa, dopamine agonists, opioids, benzodiazepines, antiepileptic drugs and iron supplements.

Progressive development of augmentation during long-term treatment with levodopa in restless legs syndrome: results of a prospective multi-center study

The European Restless Legs Syndrome (RLS) Study Group performed the first multi-center, long-term study systematically evaluating RLS augmentation under levodopa treatment. This prospective, open-label 6-month study was conducted in six European countries and included 65 patients (85% treatment naive) with idiopathic RLS. Levodopa was flexibly up-titrated to a maximum dose of 600 mg/day. Presence of augmentation was diagnosed independently by two international experts using established criteria. In addition to the augmentation severity rating scale (ASRS), changes in RLS severity (International RLS severity rating scale (IRLS), clinical global impression (CGI)) were analyzed. Sixty patients provided evaluable data, 35 completed the trial and 25 dropped out. Augmentation occurred in 60% (36/60) of patients, causing 11.7% (7/60) to drop out. Median time to occurrence of augmentation was 71 days. The mean maximum dose of levodopa was 311 mg/day (SD: 105). Patients with augmentation compared to those without were significantly more likely to be on higher doses of levodopa (> or =300 mg, 83 vs. 54%, P = 0.03) and to show less improvement of symptom severity (IRLS, P = 0.039). Augmentation was common with levodopa, but could be tolerated by most patients during this 6-month trial. Patients should be followed over longer periods to determine if dropout rates increase with time.